Fix empty input movement

# Conflicts:
#	core/src/main/java/it/cavallium/warppi/gui/CalculatorHUD.java

.editorconfig

@@ -0,0 +1,4 @@
+root = true
+
+[*]
+indent_style = tab

.gitignore

@@ -1,7 +1,5 @@
 *.class
 
-# Mobile Tools for Java (J2ME)
-.mtj.tmp/
 
 # Package Files #
 !/target/*.jar
@@ -9,7 +7,7 @@
 *.war
 *.jar
 *.ear
-*Thumbs.db
+Thumbs.db
 font_gputest1.rft
 font_gputest12.rft
 font_gputest2.rft
@@ -26,10 +24,11 @@ math-rules-cache.zip
 /backups/
 /Resources_and_Videos/
 
-# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
-hs_err_pid*
-/bin/
 
+# Created by https://www.gitignore.io/api/git,java,maven,eclipse,intellij,intellij+all,intellij+iml
+# Edit at https://www.gitignore.io/?templates=git,java,maven,eclipse,intellij,intellij+all,intellij+iml
+
+### Eclipse ###
 .metadata
 bin/
 tmp/
@@ -85,3 +84,262 @@ local.properties
 .cache-main
 .scala_dependencies
 .worksheet
+
+### Eclipse Patch ###
+# Eclipse Core
+.project
+
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+# Annotation Processing
+.apt_generated
+
+.sts4-cache/
+
+### Git ###
+# Created by git for backups. To disable backups in Git:
+# $ git config --global mergetool.keepBackup false
+*.orig
+
+# Created by git when using merge tools for conflicts
+*.BACKUP.*
+*.BASE.*
+*.LOCAL.*
+*.REMOTE.*
+*_BACKUP_*.txt
+*_BASE_*.txt
+*_LOCAL_*.txt
+*_REMOTE_*.txt
+
+### Intellij ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+### Intellij Patch ###
+# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721
+
+# *.iml
+# modules.xml
+# .idea/misc.xml
+# *.ipr
+
+# Sonarlint plugin
+.idea/**/sonarlint/
+
+# SonarQube Plugin
+.idea/**/sonarIssues.xml
+
+# Markdown Navigator plugin
+.idea/**/markdown-navigator.xml
+.idea/**/markdown-navigator/
+
+### Intellij+all ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+
+# Generated files
+
+# Sensitive or high-churn files
+
+# Gradle
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+
+# Mongo Explorer plugin
+
+# File-based project format
+
+# IntelliJ
+
+# mpeltonen/sbt-idea plugin
+
+# JIRA plugin
+
+# Cursive Clojure plugin
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+
+# Editor-based Rest Client
+
+# Android studio 3.1+ serialized cache file
+
+### Intellij+all Patch ###
+# Ignores the whole .idea folder and all .iml files
+# See https://github.com/joeblau/gitignore.io/issues/186 and https://github.com/joeblau/gitignore.io/issues/360
+
+.idea/
+
+# Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-249601023
+
+*.iml
+modules.xml
+.idea/misc.xml
+*.ipr
+
+# Sonarlint plugin
+.idea/sonarlint
+
+### Intellij+iml ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+
+# Generated files
+
+# Sensitive or high-churn files
+
+# Gradle
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+
+# Mongo Explorer plugin
+
+# File-based project format
+
+# IntelliJ
+
+# mpeltonen/sbt-idea plugin
+
+# JIRA plugin
+
+# Cursive Clojure plugin
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+
+# Editor-based Rest Client
+
+# Android studio 3.1+ serialized cache file
+
+### Intellij+iml Patch ###
+# Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-249601023
+
+
+### Java ###
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+### Maven ###
+target/
+pom.xml.tag
+pom.xml.releaseBackup
+pom.xml.versionsBackup
+pom.xml.next
+release.properties
+dependency-reduced-pom.xml
+buildNumber.properties
+.mvn/timing.properties
+.mvn/wrapper/maven-wrapper.jar
+.flattened-pom.xml
+
+# End of https://www.gitignore.io/api/git,java,maven,eclipse,intellij,intellij+all,intellij+iml

.gitmodules

@@ -1,6 +1,3 @@
-[submodule "Flow"]
-	path = Flow
-	url = https://github.com/Cavallium/Flow
 [submodule "bigdecimal-math"]
 	path = bigdecimal-math
 	url = https://github.com/Cavallium/bigdecimal-math

Flow

@@ -1 +0,0 @@
-Subproject commit 59b89e9d165c3fc615ca44aa742b531caf13fcb6

README.md

@@ -9,7 +9,7 @@ Step-by-step algebra calculator for Raspberry PI.
 # Live preview
 This preview has been built using TeaVM: a JVM made in javascript.
 Obviously it runs slower than the original.
-https://local.cavallium.it/webtests/warppiweb/
+https://local.cavallium.it/calculator/
 
 # Keypad PCB
 https://workspace.circuitmaker.com/Projects/Details/Andrea-Cavalli/Scientific-calculator-Keypad

bigdecimal-math

@@ -1 +1 @@
-Subproject commit b08a4a6aca41fbc6bf0c4bd252f716d518d368a5
+Subproject commit da70aa7ba3bcae0e2e76fde338c56696ff25ea96

core/.classpath

@@ -18,8 +18,9 @@
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8">
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER">
 		<attributes>
+			<attribute name="module" value="true"/>
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>

core/pom.xml

@@ -6,7 +6,7 @@
 	<parent>
 		<groupId>it.cavallium</groupId>
 		<artifactId>warppi</artifactId>
-		<version>0.9.0a3</version>
+		<version>0.10.0-alpha</version>
 	</parent>
 	<artifactId>warppi-core</artifactId>
 
@@ -14,20 +14,15 @@
 	<description>WarpPI Calculator core project</description>
 
 	<dependencies>
-		<dependency>
-			<groupId>it.cavallium</groupId>
-			<artifactId>warppi-flow</artifactId>
-			<version>0.9.0a3</version>
-		</dependency>
 		<dependency>
 			<groupId>it.cavallium</groupId>
 			<artifactId>warppi-util</artifactId>
-			<version>0.9.0a3</version>
+			<version>0.10.0-alpha</version>
 		</dependency>
 		<dependency>
 			<groupId>it.cavallium</groupId>
 			<artifactId>bigdecimal-math</artifactId>
-			<version>0.9.0a3</version>
+			<version>0.10.0-alpha</version>
 		</dependency>
 		<dependency>
 			<groupId>it.unimi.dsi</groupId>
@@ -46,11 +41,22 @@
 			<artifactId>commons-lang3</artifactId>
 		</dependency>
 		<dependency>
-			<groupId>junit</groupId>
-			<artifactId>junit</artifactId>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter</artifactId>
 			<scope>test</scope>
 		</dependency>
-	</dependencies>
+		<dependency>
+			<groupId>com.flowpowered</groupId>
+			<artifactId>flow-nbt</artifactId>
+			<version>1.0.1-SNAPSHOT</version>
+		</dependency>
+        <dependency>
+            <groupId>org.jetbrains</groupId>
+            <artifactId>annotations</artifactId>
+            <version>RELEASE</version>
+            <scope>compile</scope>
+        </dependency>
+    </dependencies>
 
 	<build>
 		<plugins>

core/src/main/java/it/cavallium/warppi/Engine.java

@@ -1,146 +0,0 @@
-package it.cavallium.warppi;
-
-import java.io.IOException;
-
-import it.cavallium.warppi.Platform.ConsoleUtils;
-import it.cavallium.warppi.boot.StartupArguments;
-import it.cavallium.warppi.device.HardwareDevice;
-import it.cavallium.warppi.device.HardwareTouchDevice;
-import it.cavallium.warppi.device.InputManager;
-import it.cavallium.warppi.device.Keyboard;
-import it.cavallium.warppi.flow.BehaviorSubject;
-import it.cavallium.warppi.flow.Observable;
-import it.cavallium.warppi.gui.DisplayManager;
-import it.cavallium.warppi.gui.HUD;
-import it.cavallium.warppi.gui.HardwareDisplay;
-import it.cavallium.warppi.gui.screens.Screen;
-import it.cavallium.warppi.util.ClassUtils;
-
-public class Engine {
-	public static final Engine INSTANCE = new Engine();
-	private static Platform platform;
-	private static boolean running = false;
-	private static BehaviorSubject<LoadingStatus> loadPhase = BehaviorSubject.create();
-	private final BehaviorSubject<Boolean> loaded = BehaviorSubject.create(false);
-	private HardwareDevice hardwareDevice;
-
-	private Engine() {}
-
-	/**
-	 * Start an instance of the calculator.
-	 *
-	 * @param platform
-	 *            Platform implementation
-	 * @param screen
-	 *            Default screen to show at startup
-	 * @param disp
-	 *            Hardware display
-	 * @param hud
-	 *            Head-up display
-	 * @param args
-	 *            Startup arguments
-	 * @throws InterruptedException
-	 * @throws IOException
-	 */
-	public static void start(final Platform platform, final Screen screen, final HardwareDisplay disp,
-			final HardwareTouchDevice touchdevice, final HUD hud, final StartupArguments args)
-			throws InterruptedException, IOException {
-		if (Engine.running) {
-			throw new RuntimeException("Already running!");
-		} else {
-			Engine.running = true;
-			Engine.INSTANCE.startInstance(platform, screen, disp, touchdevice, hud, args);
-		}
-	}
-
-	private void startInstance(final Platform platform, final Screen screen, final HardwareDisplay disp,
-			final HardwareTouchDevice touchdevice, final HUD hud, final StartupArguments args)
-			throws InterruptedException, IOException {
-		Engine.platform = platform;
-		platform.getConsoleUtils().out().println("WarpPI Calculator");
-		initializeEnvironment(args);
-
-		final Thread currentThread = Thread.currentThread();
-		currentThread.setPriority(Thread.MAX_PRIORITY);
-		Engine.getPlatform().setThreadName(currentThread, "Main thread");
-
-		final DisplayManager dm = new DisplayManager(disp, hud, screen, "WarpPI Calculator by Andrea Cavalli (@Cavallium)");
-		final Keyboard k = new Keyboard();
-		final InputManager im = new InputManager(k, touchdevice);
-		hardwareDevice = new HardwareDevice(dm, im);
-
-		hardwareDevice.setup(() -> Engine.loadPhase.onNext(new LoadingStatus()));
-	}
-
-	private void onShutdown() {
-		Engine.platform.getConsoleUtils().out().println(1, "Shutdown...");
-		beforeShutdown();
-		Engine.platform.getConsoleUtils().out().println(1, "");
-		Engine.platform.getConsoleUtils().out().println(1, "Closed.");
-		Engine.getPlatform().exit(0);
-	}
-
-	private void initializeEnvironment(final StartupArguments args) throws IOException {
-		ClassUtils.classLoader = this.getClass();
-		StaticVars.startupArguments = args;
-		StaticVars.debugWindow2x = args.isZoomed();
-		if (args.isVerboseLoggingEnabled() || args.isDebugEnabled()) {
-			StaticVars.outputLevel = ConsoleUtils.OUTPUTLEVEL_DEBUG_VERBOSE;
-		}
-		Engine.platform.getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, args);
-		checkDeviceType();
-		if (args.isRaspberryModeAllowed() == false) {
-			Engine.getPlatform().setRunningOnRaspberry(false);
-		}
-		if (Engine.getPlatform().isRunningOnRaspberry()) {
-			Engine.getPlatform().getGpio().wiringPiSetupPhys();
-			Engine.getPlatform().getGpio().pinMode(12, Engine.getPlatform().getGpio().valuePwmOutput());
-		} else {
-			StaticVars.screenPos = new int[] { 0, 0 };
-			if (Engine.getPlatform().isJavascript() == false) {
-				Engine.getPlatform().getSettings().setDebugEnabled(true);
-			}
-		}
-	}
-
-	private void checkDeviceType() {
-		// TODO Auto-generated method stub
-
-	}
-
-	public void beforeShutdown() {
-		Keyboard.stopKeyboard();
-	}
-
-	public Observable<Boolean> isLoaded() {
-		return loaded;
-	}
-
-	public Observable<LoadingStatus> getLoadPhase() {
-		return Engine.loadPhase;
-	}
-
-	public HardwareDevice getHardwareDevice() {
-		return hardwareDevice;
-	}
-
-	public static Platform getPlatform() {
-		return Engine.platform;
-	}
-
-	public static class LoadingStatus {
-		protected LoadingStatus() {
-
-		}
-
-		public void done() {
-			Engine.INSTANCE.loaded.onNext(true);
-			Engine.INSTANCE.hardwareDevice.getDisplayManager().waitForExit();
-			Engine.INSTANCE.onShutdown();
-		}
-
-		public void failed() {
-			Engine.INSTANCE.onShutdown();
-		}
-	}
-}

core/src/main/java/it/cavallium/warppi/Platform.java

@@ -3,13 +3,16 @@ package it.cavallium.warppi;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.PrintWriter;
 import java.net.URISyntaxException;
 import java.net.URL;
 import java.util.List;
-import java.util.Map;
 
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+import it.cavallium.warppi.boot.StartupArguments;
+import it.cavallium.warppi.device.DeviceStateDevice;
+import it.cavallium.warppi.device.display.BacklightOutputDevice;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.KeyboardInputDevice;
+import it.cavallium.warppi.device.input.TouchInputDevice;
 import it.cavallium.warppi.util.Error;
 
 public interface Platform {
@@ -18,7 +21,7 @@ public interface Platform {
 
 	Gpio getGpio();
 
-	StorageUtils getStorageUtils();
+	PlatformStorage getPlatformStorage();
 
 	ImageUtils getImageUtils();
 
@@ -52,21 +55,29 @@ public interface Platform {
 
 	URLClassLoader newURLClassLoader(URL[] urls);
 
-	Map<String, GraphicEngine> getEnginesList();
+	TouchInputDevice getTouchInputDevice();
+	
+	KeyboardInputDevice getKeyboardInputDevice();
+	
+	DisplayOutputDevice getDisplayOutputDevice();
 
-	GraphicEngine getEngine(String string) throws NullPointerException;
+	BacklightOutputDevice getBacklightOutputDevice();
 
+	DeviceStateDevice getDeviceStateDevice();
+	
 	void throwNewExceptionInInitializerError(String text);
 
 	String[] stacktraceToString(Error e);
 
-	void loadPlatformRules();
-
-	void zip(String targetPath, String destinationFilePath, String password);
-
-	void unzip(String targetZipFilePath, String destinationFolderPath, String password);
-
-	boolean compile(String[] command, PrintWriter printWriter, PrintWriter errors);
+	/**
+	 * Determines the list of files containing DSL rules to load.
+	 *
+	 * @return a <code>List</code> of paths of files which contain DSL rules.
+	 * 		   Each <code>String</code> in the returned <code>List</code> can be passed as an argument to
+	 * 		   {@link PlatformStorage#getResourceStream(String)} to access the corresponding file's contents.
+	 * @throws IOException if an IO error occurs while getting the list of rule file paths.
+	 */
+	List<String> getRuleFilePaths() throws IOException;
 
 	public interface Gpio {
 		int valueOutput();
@@ -97,7 +108,7 @@ public interface Platform {
 
 		Object getBoardType();
 	}
-
+	
 	public interface ConsoleUtils {
 		int OUTPUTLEVEL_NODEBUG = 0;
 		int OUTPUTLEVEL_DEBUG_MIN = 1;
@@ -122,7 +133,7 @@ public interface Platform {
 		}
 	}
 
-	public interface StorageUtils {
+	public interface PlatformStorage {
 		int OpenOptionWrite = 0;
 		int OpenOptionCreate = 1;
 
@@ -157,7 +168,7 @@ public interface Platform {
 
 		List<String> readAllLines(InputStream input) throws IOException;
 
-		String getBasePath();
+		File getRootPath();
 	}
 
 	public interface Semaphore {
@@ -204,4 +215,6 @@ public interface Platform {
 
 	}
 
+	void setArguments(StartupArguments args);
+
 }

core/src/main/java/it/cavallium/warppi/StaticVars.java

@@ -1,29 +1,15 @@
 package it.cavallium.warppi;
 
-import java.util.function.Function;
-
 import it.cavallium.warppi.boot.StartupArguments;
-import it.cavallium.warppi.flow.BehaviorSubject;
-import it.cavallium.warppi.flow.Observable;
+import it.cavallium.warppi.util.EventSubmitter;
 
 /*
  * TODO: Move everything to Engine.Settings
  */
 public class StaticVars {
-	public static final boolean zoomed = true;
-	public static int[] screenPos = new int[] { 0, 0 };
-	public static final int[] screenSize = new int[] { 480, 320 };
+	public static final boolean zoomedFonts = true;
 	public static int outputLevel = 0;
-	public static boolean debugWindow2x = false;
-	public static BehaviorSubject<Float> windowZoom = BehaviorSubject.create(2F);
-	public static Function<Float, Float> windowZoomFunction = (val) -> {
-		if (StaticVars.debugWindow2x) {
-			return val + 1;
-		} else {
-			return val;
-		}
-	};
-	public static Observable<Float> windowZoom$ = StaticVars.windowZoom.map(StaticVars.windowZoomFunction);
+	public static EventSubmitter<Float> windowZoom = new EventSubmitter<>(1F);
 	public static StartupArguments startupArguments;
 
 	private StaticVars() {

core/src/main/java/it/cavallium/warppi/WarpPI.java

@@ -0,0 +1,143 @@
+package it.cavallium.warppi;
+
+import it.cavallium.warppi.Platform.ConsoleUtils;
+import it.cavallium.warppi.boot.StartupArguments;
+import it.cavallium.warppi.device.Device;
+import it.cavallium.warppi.device.DeviceStateDevice;
+import it.cavallium.warppi.device.display.BacklightOutputDevice;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.InputManager;
+import it.cavallium.warppi.device.input.Keyboard;
+import it.cavallium.warppi.device.input.KeyboardInputDevice;
+import it.cavallium.warppi.device.input.TouchInputDevice;
+import it.cavallium.warppi.gui.DisplayManager;
+import it.cavallium.warppi.gui.HUD;
+import it.cavallium.warppi.gui.screens.Screen;
+import it.cavallium.warppi.util.ClassUtils;
+import it.cavallium.warppi.util.EventSubmitter;
+import it.cavallium.warppi.util.RunnableWithException;
+
+import java.io.IOException;
+
+public class WarpPI {
+	public static final WarpPI INSTANCE = new WarpPI();
+	private static Platform platform;
+	private static boolean running = false;
+	private final EventSubmitter<Boolean> loaded = EventSubmitter.create(false);
+	private Device device;
+
+	private WarpPI() {
+	}
+
+	/**
+	 * Start an instance of the calculator.
+	 *
+	 * @param platform Platform implementation
+	 * @param screen   Default screen to show at startup
+	 * @param hud      Head-up display
+	 * @param args     Startup arguments
+	 * @throws InterruptedException
+	 * @throws IOException
+	 */
+	public static void start(final Platform platform, final Screen screen, final HUD hud, final StartupArguments args, final RunnableWithException onLoading) throws IOException {
+		if (WarpPI.running) {
+			throw new RuntimeException("Already running!");
+		} else {
+			WarpPI.running = true;
+			WarpPI.INSTANCE.startInstance(platform, screen, hud, args, onLoading);
+		}
+	}
+
+	private void startInstance(final Platform platform, final Screen screen,
+	                           final HUD hud, final StartupArguments args, final RunnableWithException onLoading)
+		throws IOException {
+		WarpPI.platform = platform;
+		// Set arguments on platform before everything else
+		platform.setArguments(args);
+
+		platform.getConsoleUtils().out().println("WarpPI Calculator");
+		initializeEnvironment(args);
+
+		final Thread currentThread = Thread.currentThread();
+		currentThread.setPriority(Thread.MAX_PRIORITY);
+		WarpPI.getPlatform().setThreadName(currentThread, "Main thread");
+
+		try {
+			final DisplayOutputDevice display = platform.getDisplayOutputDevice();
+			final BacklightOutputDevice backlight = platform.getBacklightOutputDevice();
+			final DisplayManager dm = new DisplayManager(display, backlight, hud, screen, "WarpPI Calculator by Andrea Cavalli (@Cavallium)");
+			final KeyboardInputDevice keyboard = platform.getKeyboardInputDevice();
+			final TouchInputDevice touchscreen = platform.getTouchInputDevice();
+			final DeviceStateDevice deviceState = platform.getDeviceStateDevice();
+			final InputManager im = new InputManager(keyboard, touchscreen);
+			device = new Device(dm, im, deviceState);
+			device.setup();
+			onLoading.run();
+			this.loadingCompleted();
+		} catch (Exception ex) {
+			this.loadingFailed(ex);
+		}
+		this.onShutdown();
+	}
+
+	private void onShutdown() {
+		WarpPI.platform.getConsoleUtils().out().println(1, "Shutdown...");
+		beforeShutdown();
+		WarpPI.platform.getConsoleUtils().out().println(1, "");
+		WarpPI.platform.getConsoleUtils().out().println(1, "Closed.");
+		WarpPI.getPlatform().exit(0);
+	}
+
+	private void initializeEnvironment(final StartupArguments args) throws IOException {
+		ClassUtils.classLoader = this.getClass();
+		StaticVars.startupArguments = args;
+		StaticVars.windowZoom.submit(args.isZoomed() ? 2f : 1f);
+		if (args.isVerboseLoggingEnabled() || args.isDebugEnabled()) {
+			StaticVars.outputLevel = ConsoleUtils.OUTPUTLEVEL_DEBUG_VERBOSE;
+		}
+		WarpPI.platform.getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, args);
+		checkDeviceType();
+		if (args.isRaspberryModeAllowed() == false) {
+			WarpPI.getPlatform().setRunningOnRaspberry(false);
+		}
+		if (WarpPI.getPlatform().isRunningOnRaspberry()) {
+			WarpPI.getPlatform().getGpio().wiringPiSetupPhys();
+			WarpPI.getPlatform().getGpio().pinMode(12, WarpPI.getPlatform().getGpio().valuePwmOutput());
+		} else {
+			if (WarpPI.getPlatform().isJavascript() == false) {
+				WarpPI.getPlatform().getSettings().setDebugEnabled(true);
+			}
+		}
+	}
+
+	private void checkDeviceType() {
+		// TODO Auto-generated method stub
+
+	}
+
+	public void beforeShutdown() {
+		Keyboard.stopKeyboard();
+	}
+
+	public EventSubmitter<Boolean> isLoaded() {
+		return loaded;
+	}
+
+	public Device getHardwareDevice() {
+		return device;
+	}
+
+	public static Platform getPlatform() {
+		return WarpPI.platform;
+	}
+
+
+	private void loadingCompleted() {
+		WarpPI.INSTANCE.loaded.submit(true);
+		WarpPI.INSTANCE.device.getDeviceStateDevice().waitForExit();
+	}
+
+	private void loadingFailed(Exception e) {
+		e.printStackTrace();
+	}
+}

core/src/main/java/it/cavallium/warppi/boot/Boot.java

@@ -1,81 +1,77 @@
-package it.cavallium.warppi.boot;
-
-import java.util.Arrays;
-
-import it.cavallium.warppi.Engine;
-import it.cavallium.warppi.Engine.LoadingStatus;
+package it.cavallium.warppi.boot; 
+ 
+import java.util.Arrays; 
+import java.util.concurrent.Future; 
+ 
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.Platform;
-import it.cavallium.warppi.device.PIHardwareDisplay;
-import it.cavallium.warppi.device.PIHardwareTouchDevice;
-import it.cavallium.warppi.gui.CalculatorHUD;
-import it.cavallium.warppi.gui.screens.LoadingScreen;
-import it.cavallium.warppi.math.rules.RulesManager;
-import it.cavallium.warppi.util.Error;
-
-public class Boot {
-
-	public static void boot(final Platform platform, final String[] args) throws Exception {
-		Engine.start(platform, new LoadingScreen(), new PIHardwareDisplay(), new PIHardwareTouchDevice(false, false, false), new CalculatorHUD(), Boot.parseStartupArguments(args));
-		Engine.INSTANCE.getLoadPhase().subscribe(Boot::loadCalculator);
-	}
-
-	private static void loadCalculator(final LoadingStatus loading) {
-		try {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().setBrightness(0.2f);
-			RulesManager.initialize();
-			RulesManager.warmUp();
-			loading.done();
-		} catch (InterruptedException | Error e) {
-			e.printStackTrace();
-		}
-		loading.failed();
-	}
-
-	public static StartupArguments parseStartupArguments(final String[] a) {
-		final StartupArgumentsImpl args = new StartupArgumentsImpl();
-		Arrays.asList(a).stream().parallel().filter((x) -> x != null).map(String::toLowerCase).forEach(arg -> Boot.parseArgument(args, arg));
-		return args;
-	}
-
-	public static void parseArgument(final StartupArgumentsImpl args, final String arg) {
-		switch (arg) {
-			case "-zoomed":
-				args.setZoomed(true);
-				break;
-			case "-verbose":
-				args.setVerboseLoggingEnabled(true);
-				break;
-			case "-noraspi":
-				args.setRaspberryModeAllowed(false);
-				break;
-			case "nogui":
-				args.setNoGUIEngineForced(true);
-				break;
-			case "ms-dos":
-				args.setMSDOSModeEnabled(true);
-				break;
-			case "html":
-				args.setHTMLEngineForced(true);
-				break;
-			case "gpu":
-				args.setGPUEngineForced(true);
-				break;
-			case "cpu":
-				args.setCPUEngineForced(true);
-				break;
-			case "framebuffer":
-				args.setFrameBufferEngineForced(true);
-				break;
-			case "-debug":
-				args.setDebugEnabled(true);
-				break;
-			case "-uncached":
-				args.setUncached(true);
-				break;
-			default:
-				// Not using ConsoleUtils because it isn't initialized at this point.
-				System.out.println("Unrecognized argument " + arg);
-				break;
-		}
-	}
-}
+import it.cavallium.warppi.gui.CalculatorHUD; 
+import it.cavallium.warppi.gui.screens.LoadingScreen; 
+import it.cavallium.warppi.math.rules.RulesManager; 
+ 
+public class Boot { 
+ 
+	public static void boot(final Platform platform, final String[] args) throws Exception { 
+		WarpPI.start(
+				platform, 
+				new LoadingScreen(), 
+				new CalculatorHUD(), 
+				Boot.parseStartupArguments(args), 
+				Boot::loadCalculator);
+	} 
+ 
+	private static void loadCalculator() throws Exception { 
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().setBrightness(0.2f); 
+		//TODO: plugins system: PluginsManager.initialize(); 
+		RulesManager.initialize(); 
+		RulesManager.warmUp(); 
+	} 
+ 
+	public static StartupArguments parseStartupArguments(final String[] a) { 
+		final StartupArgumentsImpl args = new StartupArgumentsImpl(); 
+		Arrays.asList(a).stream().parallel().filter((x) -> x != null).map(String::toLowerCase).forEach(arg -> Boot.parseArgument(args, arg)); 
+		return args; 
+	} 
+ 
+	public static void parseArgument(final StartupArgumentsImpl args, final String arg) { 
+		switch (arg) { 
+			case "-zoomed": 
+				args.setZoomed(true); 
+				break; 
+			case "-verbose": 
+				args.setVerboseLoggingEnabled(true); 
+				break; 
+			case "-noraspi": 
+				args.setRaspberryModeAllowed(false); 
+				break; 
+				case "nogui":
+				args.setNoGUIEngineForced(true); 
+				break; 
+			case "ms-dos": 
+				args.setMSDOSModeEnabled(true); 
+				break; 
+			case "html": 
+				args.setHTMLEngineForced(true); 
+				break; 
+			case "gpu": 
+				args.setGPUEngineForced(true); 
+				break; 
+			case "cpu": 
+				args.setCPUEngineForced(true); 
+				break; 
+			case "framebuffer": 
+				args.setFrameBufferEngineForced(true); 
+				break; 
+			case "-debug": 
+				args.setDebugEnabled(true); 
+				break; 
+			case "-uncached": 
+				args.setUncached(true); 
+				break; 
+			default: 
+				// Not using ConsoleUtils because it isn't initialized at this point. 
+				System.out.println("Unrecognized argument " + arg); 
+				break; 
+		} 
+	} 
+} 

core/src/main/java/it/cavallium/warppi/device/CacheFile.java

@@ -8,7 +8,7 @@ import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.UUID;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 
 public class CacheFile {
 	private String path;
@@ -22,7 +22,7 @@ public class CacheFile {
 			path = UUID.randomUUID().toString() + ".ser";
 		} while (new File(path).exists());
 		try {
-			File.createTempFile(Engine.getPlatform().getSettings().getCalculatorNameLowercase(), "");
+			File.createTempFile(WarpPI.getPlatform().getSettings().getCalculatorNameLowercase(), "");
 		} catch (final IOException e) {
 			e.printStackTrace();
 		}

core/src/main/java/it/cavallium/warppi/device/Device.java

@@ -0,0 +1,38 @@
+package it.cavallium.warppi.device;
+
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.input.InputManager;
+import it.cavallium.warppi.gui.DisplayManager;
+
+public class Device {
+	private final DisplayManager displayManager;
+	private final InputManager inputManager;
+	private final DeviceStateDevice deviceState;
+
+	public Device(final DisplayManager m, final InputManager im, final DeviceStateDevice dm) {
+		displayManager = m;
+		inputManager = im;
+		deviceState = dm;
+	}
+
+	public DisplayManager getDisplayManager() {
+		return displayManager;
+	}
+
+	public InputManager getInputManager() {
+		return inputManager;
+	}
+	
+	public DeviceStateDevice getDeviceStateDevice() {
+		return deviceState;
+	}
+
+	public void setup() {
+		displayManager.initialize();
+		inputManager.initialize();
+		deviceState.initialize();
+		
+		inputManager.getTouchDevice().listenTouchEvents(displayManager.getTouchEventListener());
+	}
+
+}

core/src/main/java/it/cavallium/warppi/device/DeviceStateDevice.java

@@ -0,0 +1,12 @@
+package it.cavallium.warppi.device;
+
+import java.util.concurrent.Future;
+
+public interface DeviceStateDevice {
+
+	void initialize();
+
+	void waitForExit();
+	
+	void powerOff();
+}

core/src/main/java/it/cavallium/warppi/device/HardwareDevice.java

@@ -1,32 +0,0 @@
-package it.cavallium.warppi.device;
-
-import it.cavallium.warppi.Engine;
-import it.cavallium.warppi.gui.DisplayManager;
-
-public class HardwareDevice {
-	private final DisplayManager displayManager;
-	private final InputManager inputManager;
-
-	public HardwareDevice(final DisplayManager m, final InputManager im) {
-		displayManager = m;
-		inputManager = im;
-	}
-
-	public DisplayManager getDisplayManager() {
-		return displayManager;
-	}
-
-	public InputManager getInputManager() {
-		return inputManager;
-	}
-
-	public void setup(final Runnable r) {
-		displayManager.initialize();
-		inputManager.getKeyboard().startKeyboard();
-		final Thread t = new Thread(r);
-		Engine.getPlatform().setThreadDaemon(t, false);
-		Engine.getPlatform().setThreadName(t, "Main thread (after setup)");
-		t.start();
-	}
-
-}

core/src/main/java/it/cavallium/warppi/device/HardwareTouchDevice.java

@@ -1,21 +0,0 @@
-package it.cavallium.warppi.device;
-
-import it.cavallium.warppi.event.TouchEventListener;
-import it.cavallium.warppi.event.TouchPoint;
-
-public interface HardwareTouchDevice extends TouchEventListener {
-	boolean getInvertedXY();
-
-	boolean getInvertedX();
-
-	boolean getInvertedY();
-
-	default void setInvertedXY() {}
-
-	default void setInvertedX() {}
-
-	default void setInvertedY() {}
-
-	TouchPoint makePoint(long id, float x, float y, int maxX, int maxY, float radiusX, float radiusY, float force,
-			float rotationAngle);
-}

core/src/main/java/it/cavallium/warppi/device/InputManager.java

@@ -1,20 +0,0 @@
-package it.cavallium.warppi.device;
-
-public class InputManager {
-	private final Keyboard keyboard;
-	private final HardwareTouchDevice touchDevice;
-
-	public InputManager(final Keyboard k, final HardwareTouchDevice t) {
-		keyboard = k;
-		touchDevice = t;
-	}
-
-	public Keyboard getKeyboard() {
-		return keyboard;
-	}
-
-	public HardwareTouchDevice getTouchDevice() {
-		return touchDevice;
-	}
-
-}

core/src/main/java/it/cavallium/warppi/device/PIHardwareDisplay.java

@@ -1,24 +0,0 @@
-package it.cavallium.warppi.device;
-
-import it.cavallium.warppi.Engine;
-import it.cavallium.warppi.gui.HardwareDisplay;
-
-public class PIHardwareDisplay implements HardwareDisplay {
-
-	@Override
-	public void initialize() {}
-
-	@Override
-	public void shutdown() {}
-
-	@Override
-	public void setBrightness(final double value) {
-		if (Engine.getPlatform().isRunningOnRaspberry()) {
-			Engine.getPlatform().getGpio().pwmWrite(12, (int) Math.ceil(value * 1024f));
-//			SoftPwm.softPwmWrite(12, (int)(Math.ceil(brightness*10)));
-		} else {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Brightness: " + value);
-		}
-	}
-
-}

core/src/main/java/it/cavallium/warppi/device/PIHardwareTouchDevice.java

@@ -1,113 +0,0 @@
-package it.cavallium.warppi.device;
-
-import it.cavallium.warppi.Engine;
-import it.cavallium.warppi.event.TouchCancelEvent;
-import it.cavallium.warppi.event.TouchEndEvent;
-import it.cavallium.warppi.event.TouchMoveEvent;
-import it.cavallium.warppi.event.TouchPoint;
-import it.cavallium.warppi.event.TouchStartEvent;
-import it.cavallium.warppi.gui.screens.Screen;
-
-public class PIHardwareTouchDevice implements HardwareTouchDevice {
-
-	private final boolean invertXY, invertX, invertY;
-
-	public PIHardwareTouchDevice(final boolean invertXY, final boolean invertX, final boolean invertY) {
-		this.invertXY = invertXY;
-		this.invertX = invertX;
-		this.invertY = invertY;
-	}
-
-	@Override
-	public boolean onTouchStart(final TouchStartEvent e) {
-		final Screen scr = Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
-		boolean refresh = false;
-		if (scr != null && scr.initialized && scr.onTouchStart(e)) {
-			refresh = true;
-		} else {
-			//Default behavior
-		}
-		if (refresh) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().forceRefresh = true;
-		}
-		return true;
-	}
-
-	@Override
-	public boolean onTouchEnd(final TouchEndEvent e) {
-		final Screen scr = Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
-		boolean refresh = false;
-		if (scr != null && scr.initialized && scr.onTouchEnd(e)) {
-			refresh = true;
-		} else {
-			//Default behavior
-		}
-		if (refresh) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().forceRefresh = true;
-		}
-		return true;
-	}
-
-	@Override
-	public boolean onTouchCancel(final TouchCancelEvent e) {
-		final Screen scr = Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
-		boolean refresh = false;
-		if (scr != null && scr.initialized && scr.onTouchCancel(e)) {
-			refresh = true;
-		} else {
-			//Default behavior
-		}
-		if (refresh) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().forceRefresh = true;
-		}
-		return true;
-	}
-
-	@Override
-	public boolean onTouchMove(final TouchMoveEvent e) {
-		final Screen scr = Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
-		boolean refresh = false;
-		if (scr != null && scr.initialized && scr.onTouchMove(e)) {
-			refresh = true;
-		} else {
-			//Default behavior
-		}
-		if (refresh) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().forceRefresh = true;
-		}
-		return true;
-	}
-
-	@Override
-	public boolean getInvertedXY() {
-		return invertXY;
-	}
-
-	@Override
-	public boolean getInvertedX() {
-		return invertX;
-	}
-
-	@Override
-	public boolean getInvertedY() {
-		return invertY;
-	}
-
-	@Override
-	public TouchPoint makePoint(final long id, float x, float y, final int screenWidth, final int screenHeight,
-			final float radiusX, final float radiusY, final float force, final float rotationAngle) {
-		if (getInvertedXY()) {
-			final double oldX = x;
-			final double oldY = y;
-			x = (float) (oldY * screenWidth / screenHeight);
-			y = (float) (oldX * screenHeight / screenWidth);
-		}
-		if (getInvertedX()) {
-			x = screenWidth - x;
-		}
-		if (getInvertedY()) {
-			y = screenHeight - y;
-		}
-		return new TouchPoint(id, x, y, radiusX, radiusY, force, rotationAngle);
-	}
-}

core/src/main/java/it/cavallium/warppi/device/chip/ParallelToSerial.java

@@ -1,6 +1,6 @@
 package it.cavallium.warppi.device.chip;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 
 public class ParallelToSerial {
 
@@ -18,16 +18,16 @@ public class ParallelToSerial {
 
 	public boolean[] read() {
 		final boolean[] data = new boolean[8];
-		Engine.getPlatform().getGpio().digitalWrite(CLK_INH, Engine.getPlatform().getGpio().valueHigh());
-		Engine.getPlatform().getGpio().digitalWrite(SH_LD, Engine.getPlatform().getGpio().valueLow());
-		Engine.getPlatform().getGpio().delayMicroseconds(1);
-		Engine.getPlatform().getGpio().digitalWrite(SH_LD, Engine.getPlatform().getGpio().valueHigh());
-		Engine.getPlatform().getGpio().digitalWrite(CLK_INH, Engine.getPlatform().getGpio().valueLow());
+		WarpPI.getPlatform().getGpio().digitalWrite(CLK_INH, WarpPI.getPlatform().getGpio().valueHigh());
+		WarpPI.getPlatform().getGpio().digitalWrite(SH_LD, WarpPI.getPlatform().getGpio().valueLow());
+		WarpPI.getPlatform().getGpio().delayMicroseconds(1);
+		WarpPI.getPlatform().getGpio().digitalWrite(SH_LD, WarpPI.getPlatform().getGpio().valueHigh());
+		WarpPI.getPlatform().getGpio().digitalWrite(CLK_INH, WarpPI.getPlatform().getGpio().valueLow());
 
 		for (int i = 7; i >= 0; i--) {
-			Engine.getPlatform().getGpio().digitalWrite(CLK, Engine.getPlatform().getGpio().valueHigh());
-			Engine.getPlatform().getGpio().digitalWrite(CLK, Engine.getPlatform().getGpio().valueLow());
-			data[i] = Engine.getPlatform().getGpio().digitalRead(QH) == Engine.getPlatform().getGpio().valueHigh() ? true : false;
+			WarpPI.getPlatform().getGpio().digitalWrite(CLK, WarpPI.getPlatform().getGpio().valueHigh());
+			WarpPI.getPlatform().getGpio().digitalWrite(CLK, WarpPI.getPlatform().getGpio().valueLow());
+			data[i] = WarpPI.getPlatform().getGpio().digitalRead(QH) == WarpPI.getPlatform().getGpio().valueHigh() ? true : false;
 		}
 
 		return data;

core/src/main/java/it/cavallium/warppi/device/chip/SerialToParallel.java

@@ -1,6 +1,6 @@
 package it.cavallium.warppi.device.chip;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 
 public class SerialToParallel {
 	private final int RCK; //Storage register clock pin (latch pin)
@@ -17,15 +17,15 @@ public class SerialToParallel {
 		if (data.length != 8) {
 			return;
 		} else {
-			Engine.getPlatform().getGpio().digitalWrite(RCK, Engine.getPlatform().getGpio().valueLow());
+			WarpPI.getPlatform().getGpio().digitalWrite(RCK, WarpPI.getPlatform().getGpio().valueLow());
 
 			for (int i = 7; i >= 0; i--) {
-				Engine.getPlatform().getGpio().digitalWrite(SCK, Engine.getPlatform().getGpio().valueLow());
-				Engine.getPlatform().getGpio().digitalWrite(SER, data[i]);
-				Engine.getPlatform().getGpio().digitalWrite(SCK, Engine.getPlatform().getGpio().valueHigh());
+				WarpPI.getPlatform().getGpio().digitalWrite(SCK, WarpPI.getPlatform().getGpio().valueLow());
+				WarpPI.getPlatform().getGpio().digitalWrite(SER, data[i]);
+				WarpPI.getPlatform().getGpio().digitalWrite(SCK, WarpPI.getPlatform().getGpio().valueHigh());
 			}
 
-			Engine.getPlatform().getGpio().digitalWrite(RCK, Engine.getPlatform().getGpio().valueHigh());
+			WarpPI.getPlatform().getGpio().digitalWrite(RCK, WarpPI.getPlatform().getGpio().valueHigh());
 		}
 	}
 }

core/src/main/java/it/cavallium/warppi/device/display/BacklightOutputDevice.java

@@ -0,0 +1,16 @@
+package it.cavallium.warppi.device.display;
+
+public interface BacklightOutputDevice {
+	
+	/**
+	 * Set the brightness level
+	 * @param value Value from 0.0 to 1.0
+	 */
+	void setBrightness(double value);
+	
+	/**
+	 * Turn on or off the backlight
+	 * @param value true is ON, false is OFF
+	 */
+	void setPower(boolean value);
+}

core/src/main/java/it/cavallium/warppi/device/display/DisplayOutputDevice.java

@@ -0,0 +1,8 @@
+package it.cavallium.warppi.device.display;
+
+import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+
+public interface DisplayOutputDevice {
+	public GraphicEngine getGraphicEngine();
+	public int[] getDisplaySize();
+}

core/src/main/java/it/cavallium/warppi/device/display/NoDisplaysAvailableException.java

@@ -0,0 +1,7 @@
+package it.cavallium.warppi.device.display;
+
+public class NoDisplaysAvailableException extends RuntimeException {
+
+	private static final long serialVersionUID = 1L;
+
+}

core/src/main/java/it/cavallium/warppi/device/display/NullBacklightOutputDevice.java

@@ -0,0 +1,18 @@
+package it.cavallium.warppi.device.display;
+
+public class NullBacklightOutputDevice implements BacklightOutputDevice {
+
+	private double brightness;
+	private boolean power;
+
+	@Override
+	public void setBrightness(double value) {
+		this.brightness = value;
+	}
+
+	@Override
+	public void setPower(boolean value) {
+		this.power = value;
+	}
+
+}

core/src/main/java/it/cavallium/warppi/device/display/RAWFont.java

@@ -1,4 +1,4 @@
-package it.cavallium.warppi.device.graphicengine;
+package it.cavallium.warppi.device.display;
 
 import java.io.File;
 import java.io.IOException;
@@ -7,7 +7,7 @@ import java.net.URL;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.util.ClassUtils;
 import it.cavallium.warppi.util.Utils;
 
@@ -32,7 +32,7 @@ public class RAWFont {
 			loadFont("/font_" + name + ".rft");
 		} catch (final IOException e) {
 			e.printStackTrace();
-			Engine.getPlatform().exit(1);
+			WarpPI.getPlatform().exit(1);
 		}
 		chars32 = new int[(maxBound - minBound) * charIntCount];
 		for (int charIndex = 0; charIndex < maxBound - minBound; charIndex++) {
@@ -110,7 +110,7 @@ public class RAWFont {
 					} catch (final Exception ex) {
 						ex.printStackTrace();
 						System.out.println(string);
-						Engine.getPlatform().exit(-1);
+						WarpPI.getPlatform().exit(-1);
 					}
 				}
 			} else {

core/src/main/java/it/cavallium/warppi/device/input/HardwareKeyboardDevice.java

@@ -0,0 +1,5 @@
+package it.cavallium.warppi.device.input;
+
+public interface HardwareKeyboardDevice {
+
+}

core/src/main/java/it/cavallium/warppi/device/input/InputManager.java

@@ -0,0 +1,27 @@
+package it.cavallium.warppi.device.input;
+
+import java.util.Objects;
+
+public class InputManager {
+	private final KeyboardInputDevice keyboard;
+	private final TouchInputDevice touchDevice;
+
+	public InputManager(KeyboardInputDevice keyboard, TouchInputDevice touchscreen) {
+		this.keyboard = Objects.requireNonNull(keyboard);
+		this.touchDevice = Objects.requireNonNull(touchscreen);
+	}
+
+	public KeyboardInputDevice getKeyboard() {
+		return keyboard;
+	}
+
+	public TouchInputDevice getTouchDevice() {
+		return touchDevice;
+	}
+
+	public void initialize() {
+		this.keyboard.initialize();
+		this.touchDevice.initialize();
+	}
+
+}

core/src/main/java/it/cavallium/warppi/device/input/KeyboardAWTValues.java

@@ -1,4 +1,4 @@
-package it.cavallium.warppi.device;
+package it.cavallium.warppi.device.input;
 
 public interface KeyboardAWTValues {
 

core/src/main/java/it/cavallium/warppi/device/input/KeyboardInputDevice.java

@@ -0,0 +1,7 @@
+package it.cavallium.warppi.device.input;
+
+public interface KeyboardInputDevice {
+
+	void initialize();
+
+}

core/src/main/java/it/cavallium/warppi/device/input/KeyboardJogampValues.java

@@ -1,4 +1,4 @@
-package it.cavallium.warppi.device;
+package it.cavallium.warppi.device.input;
 
 public interface KeyboardJogampValues {
 

core/src/main/java/it/cavallium/warppi/device/input/NullTouchInputDevice.java

@@ -0,0 +1,41 @@
+package it.cavallium.warppi.device.input;
+
+import java.util.function.Consumer;
+
+import it.cavallium.warppi.event.TouchEvent;
+import it.cavallium.warppi.event.TouchPoint;
+
+public class NullTouchInputDevice implements TouchInputDevice {
+
+	@Override
+	public boolean getSwappedAxes() {
+		return false;
+	}
+
+	@Override
+	public boolean getInvertedX() {
+		return false;
+	}
+
+	@Override
+	public boolean getInvertedY() {
+		return false;
+	}
+
+	@Override
+	public void listenTouchEvents(Consumer<TouchEvent> touchEventListener) {
+		
+	}
+
+	@Override
+	public void initialize() {
+		
+	}
+
+	@Override
+	public TouchPoint makePoint(long id, float x, float y, int maxX, int maxY, float radiusX, float radiusY,
+			float force, float rotationAngle) {
+		return new TouchPoint(id, maxX, maxY, radiusX, radiusY, force, rotationAngle);
+	}
+
+}

core/src/main/java/it/cavallium/warppi/device/input/TouchInputDevice.java

@@ -0,0 +1,43 @@
+package it.cavallium.warppi.device.input;
+
+import java.util.concurrent.Flow.Subscriber;
+import java.util.function.Consumer;
+
+import it.cavallium.warppi.event.TouchEvent;
+import it.cavallium.warppi.event.TouchEventListener;
+import it.cavallium.warppi.event.TouchPoint;
+
+public interface TouchInputDevice {
+	boolean getSwappedAxes();
+
+	boolean getInvertedX();
+
+	boolean getInvertedY();
+
+	default void setInvertedXY() {}
+
+	default void setInvertedX() {}
+
+	default void setInvertedY() {}
+
+	void listenTouchEvents(Consumer<TouchEvent> touchEventListener);
+	
+	default TouchPoint makePoint(final long id, float x, float y, final int screenWidth, final int screenHeight,
+			final float radiusX, final float radiusY, final float force, final float rotationAngle) {
+		if (getSwappedAxes()) {
+			final double oldX = x;
+			final double oldY = y;
+			x = (float) (oldY * screenWidth / screenHeight);
+			y = (float) (oldX * screenHeight / screenWidth);
+		}
+		if (getInvertedX()) {
+			x = screenWidth - x;
+		}
+		if (getInvertedY()) {
+			y = screenHeight - y;
+		}
+		return new TouchPoint(id, x, y, radiusX, radiusY, force, rotationAngle);
+	}
+
+	void initialize();
+}

core/src/main/java/it/cavallium/warppi/extra/mario/MarioScreen.java

@@ -1,14 +1,18 @@
 package it.cavallium.warppi.extra.mario;
 
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.StaticVars;
 import it.cavallium.warppi.Platform.ConsoleUtils;
-import it.cavallium.warppi.device.Keyboard;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.Keyboard;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.event.KeyReleasedEvent;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
 import it.cavallium.warppi.gui.graphicengine.Skin;
 import it.cavallium.warppi.gui.screens.Screen;
@@ -45,33 +49,34 @@ public class MarioScreen extends Screen {
 	}
 
 	@Override
-	public void graphicInitialized() {
+	public void graphicInitialized(ScreenContext ctx) {
 		try {
 			if (MarioScreen.skin == null) {
-				MarioScreen.skin = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("/marioskin.png");
+				MarioScreen.skin = d.display.getGraphicEngine().loadSkin("/marioskin.png");
 			}
 			if (MarioScreen.groundskin == null) {
-				MarioScreen.groundskin = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("/marioground.png");
+				MarioScreen.groundskin = d.display.getGraphicEngine().loadSkin("/marioground.png");
 			}
 			if (MarioScreen.gpuTest2 == null) {
 				try {
-					MarioScreen.gpuTest2 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest2");
+					MarioScreen.gpuTest2 = d.display.getGraphicEngine().loadFont("N:\\gputest", "gputest2");
 				} catch (final Exception ex) {}
 			}
 			if (MarioScreen.gpuTest1 == null) {
 				try {
-					MarioScreen.gpuTest1 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest12");
+					MarioScreen.gpuTest1 = d.display.getGraphicEngine().loadFont("N:\\gputest", "gputest12");
 					MarioScreen.gpuTest12 = true;
 				} catch (final Exception ex) {
 					MarioScreen.gpuTest12 = false;
 					try {
-						MarioScreen.gpuTest1 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest1");
+						MarioScreen.gpuTest1 = d.display.getGraphicEngine().loadFont("N:\\gputest", "gputest1");
 					} catch (final Exception ex2) {}
 				}
 			}
 			if (MarioScreen.gpuTest3 == null) {
 				try {
-					MarioScreen.gpuTest3 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("N:\\gputest\\font_gputest3.png");
+					MarioScreen.gpuTest3 = d.display.getGraphicEngine().loadSkin("N:\\gputest\\font_gputest3.png");
+				} catch (final NoSuchFileException ignored) {
 				} catch (final Exception ex) {
 					ex.printStackTrace();
 				}
@@ -85,30 +90,31 @@ public class MarioScreen extends Screen {
 	public void initialized() {
 		try {
 			if (MarioScreen.skin == null) {
-				MarioScreen.skin = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("/marioskin.png");
+				MarioScreen.skin = d.display.getGraphicEngine().loadSkin("/marioskin.png");
 			}
 			if (MarioScreen.groundskin == null) {
-				MarioScreen.groundskin = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("/marioground.png");
+				MarioScreen.groundskin = d.display.getGraphicEngine().loadSkin("/marioground.png");
 			}
 			if (MarioScreen.gpuTest2 == null) {
 				try {
-					MarioScreen.gpuTest2 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest2");
+					MarioScreen.gpuTest2 = d.display.getGraphicEngine().loadFont("N:\\gputest\\gputest2");
 				} catch (final Exception ex) {}
 			}
 			if (MarioScreen.gpuTest1 == null) {
 				try {
-					MarioScreen.gpuTest1 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest12");
+					MarioScreen.gpuTest1 = d.display.getGraphicEngine().loadFont("N:\\gputest\\gputest12");
 					MarioScreen.gpuTest12 = true;
 				} catch (final Exception ex) {
 					MarioScreen.gpuTest12 = false;
 					try {
-						MarioScreen.gpuTest1 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("N:\\gputest\\gputest1");
+						MarioScreen.gpuTest1 = d.display.getGraphicEngine().loadFont("N:\\gputest\\gputest1");
 					} catch (final Exception ex2) {}
 				}
 			}
 			if (MarioScreen.gpuTest3 == null) {
 				try {
-					MarioScreen.gpuTest3 = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("N:\\gputest\\font_gputest3.png");
+					MarioScreen.gpuTest3 = d.display.getGraphicEngine().loadSkin("N:\\gputest\\font_gputest3.png");
+				} catch (final NoSuchFileException ignored) {
 				} catch (final Exception ex) {
 					ex.printStackTrace();
 				}
@@ -166,7 +172,7 @@ public class MarioScreen extends Screen {
 	}
 	
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 		if (!errored) {
 			final boolean upPressed = false, downPressed = false, runPressed = false;
 			g.gameTick(dt, upPressed, downPressed, leftPressed, rightPressed, jumpPressed, runPressed);
@@ -182,89 +188,90 @@ public class MarioScreen extends Screen {
 				gpuCharTestt1Elapsed -= 1.5;
 			}
 
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glClearColor(0xff000000);
+			d.renderer.glClearColor(0xff000000);
 		}
 	}
 
 	@Override
-	public void render() {
+	public void render(RenderContext ctx) {
+		DisplayOutputDevice display = d.display;
 		if (errored) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringLeft(0, 20, "ERROR");
+			d.renderer.glDrawStringLeft(0, 20, "ERROR");
 		} else {
 			if (MarioScreen.groundskin != null) {
 				final double playerX = g.getPlayer().getX();
 				final double playerY = g.getPlayer().getY();
-				MarioScreen.groundskin.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+				MarioScreen.groundskin.use(d.display);
 				final MarioWorld w = g.getCurrentWorld();
 				final int width = w.getWidth();
 				final int height = w.getHeight();
-				final float screenX = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth() / 2f - 8f;
-				final float screenY = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() / 2f - 8f;
+				final float screenX = ctx.getWidth() / 2f - 8f;
+				final float screenY = ctx.getHeight() / 2f - 8f;
 				final float shiftX = -8 + 16 * (float) playerX;
 				final float shiftY = -8 + 16 * (height - (float) playerY);
 				int blue = -1;
 				for (int ix = 0; ix < width; ix++) {
 					for (int iy = 0; iy < height; iy++) {
 						final double distX = Math.abs(playerX - ix);
-						final double distY = Math.abs(playerY - iy - 1.5d);
-						if (distX * distX + distY * distY / 2d < 25d) {
+						final double distY = Math.abs(playerY - iy - 1.2d);
+						if (distX * distX + distY * distY / 2d < 270d) {
 							final byte b = w.getBlockIdAt(ix, iy);
 							if (b == 0) {
 								if (blue != 1) {
 									blue = 1;
-									Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xff9290ff);
+									d.renderer.glColor(0xff9290ff);
 								}
-								Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillColor(screenX - shiftX + 16 * ix, screenY - shiftY + 16 * (height - iy), 16, 16);
+								d.renderer.glFillColor(screenX - shiftX + 16 * ix, screenY - shiftY + 16 * (height - iy), 16, 16);
 							} else {
 								if (blue != 0) {
 									blue = 0;
-									Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xffffffff);
+									d.renderer.glColor(0xffffffff);
 								}
-								Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(screenX - shiftX + 16 * ix, screenY - shiftY + 16 * (height - iy), 16, 16, 0, 0, 16, 16);
+								d.renderer.glFillRect(screenX - shiftX + 16 * ix, screenY - shiftY + 16 * (height - iy), 16, 16, 0, 0, 16, 16);
 							}
 						}
 					}
 				}
 				if (blue != 0) {
 					blue = 0;
-					Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xffffffff);
+					d.renderer.glColor(0xffffffff);
 				}
 
 				//DRAW MARIO
-				MarioScreen.skin.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(screenX - (g.getPlayer().flipped ? 3 : 0), screenY, 35, 27, 35 * (g.getPlayer().marioSkinPos[0] + (g.getPlayer().flipped ? 2 : 1)), 27 * g.getPlayer().marioSkinPos[1], 35 * (g.getPlayer().flipped ? -1 : 1), 27);
+				MarioScreen.skin.use(d.display);
+				d.renderer.glFillRect(screenX - (g.getPlayer().flipped ? 3 : 0), screenY, 35, 27, 35 * (g.getPlayer().marioSkinPos[0] + (g.getPlayer().flipped ? 2 : 1)), 27 * g.getPlayer().marioSkinPos[1], 35 * (g.getPlayer().flipped ? -1 : 1), 27);
 //				PIDisplay.renderer.glDrawSkin(getPosX() - 18, 25 + getPosY(), 35 * (marioSkinPos[0] + (flipped ? 2 : 1)), 27 * marioSkinPos[1], 35 * (marioSkinPos[0] + (flipped ? 1 : 2)), 27 * (marioSkinPos[1] + 1), true);
 			}
 
 //		GPU PERFORMANCE TEST
 			if (MarioScreen.gpuTest1 != null) {
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3f(1, 1, 1);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillColor(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth() - (MarioScreen.gpuTest12 ? 512 : 256), Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() / 2 - (MarioScreen.gpuTest12 ? 256 : 128), MarioScreen.gpuTest12 ? 512 : 256, MarioScreen.gpuTest12 ? 512 : 256);
-				MarioScreen.gpuTest1.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3f(0, 0, 0);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth(), Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() / 2 - (MarioScreen.gpuTest12 ? 256 : 128), gpuCharTest1[gpuCharTest1Num]);
+				d.renderer.glColor3f(1, 1, 1);
+				d.renderer.glFillColor(ctx.getWidth() - (MarioScreen.gpuTest12 ? 512 : 256), ctx.getHeight() / 2 - (MarioScreen.gpuTest12 ? 256 : 128), MarioScreen.gpuTest12 ? 512 : 256, MarioScreen.gpuTest12 ? 512 : 256);
+				MarioScreen.gpuTest1.use(d.display);
+				d.renderer.glColor3f(0, 0, 0);
+				d.renderer.glDrawStringRight(ctx.getWidth(), ctx.getHeight() / 2 - (MarioScreen.gpuTest12 ? 256 : 128), gpuCharTest1[gpuCharTest1Num]);
 			}
 			if (MarioScreen.gpuTest3 != null) {
-				MarioScreen.gpuTest3.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor4f(1, 1, 1, 0.7f);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(0, StaticVars.screenSize[1] - 128, 224, 128, gpuTestNum * 224, 0, 224, 128);
+				MarioScreen.gpuTest3.use(d.display);
+				d.renderer.glColor4f(1, 1, 1, 0.7f);
+				d.renderer.glFillRect(0, display.getDisplaySize()[1] - 128, 224, 128, gpuTestNum * 224, 0, 224, 128);
 			}
 			if (MarioScreen.gpuTest2 != null) {
-				MarioScreen.gpuTest2.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFF000000);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "A");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFF800000);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "B");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFFeea28e);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "C");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFFee7255);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "D");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFFeac0b0);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "E");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFFf3d8ce);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "F");
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor(0xFFffede7);
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringRight(StaticVars.screenSize[0], Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "G");
+				MarioScreen.gpuTest2.use(d.display);
+				d.renderer.glColor(0xFF000000);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "A");
+				d.renderer.glColor(0xFF800000);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "B");
+				d.renderer.glColor(0xFFeea28e);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "C");
+				d.renderer.glColor(0xFFee7255);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "D");
+				d.renderer.glColor(0xFFeac0b0);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "E");
+				d.renderer.glColor(0xFFf3d8ce);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "F");
+				d.renderer.glColor(0xFFffede7);
+				d.renderer.glDrawStringRight(display.getDisplaySize()[0], ctx.getHeight() - MarioScreen.gpuTest2.getCharacterHeight(), "G");
 			}
 		}
 	}

core/src/main/java/it/cavallium/warppi/extra/tetris/TetrisScreen.java

@@ -2,14 +2,16 @@ package it.cavallium.warppi.extra.tetris;
 
 import java.io.IOException;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.Keyboard;
 import it.cavallium.warppi.StaticVars;
-import it.cavallium.warppi.device.Keyboard;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.event.KeyReleasedEvent;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.gui.graphicengine.Skin;
 import it.cavallium.warppi.gui.screens.Screen;
@@ -30,7 +32,7 @@ public class TetrisScreen extends Screen {
 
 	private ButtonInfo backPressed = new ButtonInfo();
 
-	private GraphicEngine e;
+	private DisplayOutputDevice e;
 
 	private Renderer r;
 
@@ -43,16 +45,15 @@ public class TetrisScreen extends Screen {
 
 	@Override
 	public void initialized() {
-		StaticVars.windowZoom.onNext(2f);
 	}
 
 	@Override
-	public void graphicInitialized() {
+	public void graphicInitialized(ScreenContext ctx) {
 		try {
-			e = d.engine;
+			e = d.display;
 			r = d.renderer;
 			if (TetrisScreen.skin == null) {
-				TetrisScreen.skin = Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadSkin("/tetrisskin.png");
+				TetrisScreen.skin = d.display.getGraphicEngine().loadSkin("/tetrisskin.png");
 			}
 		} catch (final IOException e) {
 			e.printStackTrace();
@@ -65,22 +66,23 @@ public class TetrisScreen extends Screen {
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glClearColor(0xff000000);
+	public void beforeRender(ScreenContext ctx, final float dt) {
+		d.renderer.glClearColor(0xff000000);
 			g.update(dt, leftPressed, rightPressed, downPressed, upPressed, okPressed, backPressed);
 	}
 
 	@Override
-	public void render() {
+	public void render(RenderContext ctx) {
+		DisplayOutputDevice display = d.display;
 		if (TetrisScreen.skin != null) {
 			TetrisScreen.skin.use(e);
 		}
 		r.glColor3f(1, 1, 1);
 		BlockColor[] renderedGrid = g.getRenderedGrid();
-		int centerScreen = StaticVars.screenSize[0]/2;
+		int centerScreen = ctx.getWidth()/2;
 		int centerGrid = TetrisGame.WIDTH*6/2-1;
 		final int leftOffset = centerScreen - centerGrid;
-		final int topOffset = StaticVars.screenSize[1] - TetrisGame.HEIGHT*6-1;
+		final int topOffset = ctx.getHeight() - TetrisGame.HEIGHT*6-1;
 		for (int y = 0; y < TetrisGame.HEIGHT; y++) {
 			for (int x = 0; x < TetrisGame.WIDTH; x++) {
 				final int offset = x+y*TetrisGame.WIDTH;

core/src/main/java/it/cavallium/warppi/gui/CalculatorHUD.java

@@ -1,8 +1,9 @@
 package it.cavallium.warppi.gui;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.Keyboard;
 import it.cavallium.warppi.StaticVars;
-import it.cavallium.warppi.device.Keyboard;
 import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.gui.graphicengine.Skin;
@@ -31,7 +32,7 @@ public class CalculatorHUD extends HUD {
 	}
 
 	@Override
-	public void render() {
+	public void render(RenderContext ctx) {
 		// TODO Auto-generated method stub
 
 	}
@@ -39,23 +40,25 @@ public class CalculatorHUD extends HUD {
 	@Override
 	public void renderTopmostBackground() {
 		final Renderer r = d.renderer;
-		final GraphicEngine engine = d.engine;
+		final DisplayOutputDevice display = d.display;
+		final GraphicEngine engine = display.getGraphicEngine();
 
 		r.glColor(0xFFc5c2af);
 		r.glFillColor(0, 0, engine.getWidth(), 20);
 	}
 
 	@Override
-	public void renderTopmost() {
-		final Renderer r = d.renderer;
-		final GraphicEngine engine = d.engine;
+	public void renderTopmost(RenderContext ctx) {
+		final Renderer r = ctx.getRenderer();
+		final DisplayOutputDevice display = d.display;
+		final GraphicEngine engine = display.getGraphicEngine();
 		final Skin guiSkin = d.guiSkin;
 
 		//DRAW TOP
 		r.glColor3i(0, 0, 0);
 		r.glDrawLine(0, 20, engine.getWidth() - 1, 20);
 		r.glColor3i(255, 255, 255);
-		guiSkin.use(engine);
+		guiSkin.use(display);
 		if (Keyboard.shift) {
 			r.glFillRect(2 + 18 * 0, 2, 16, 16, 16 * 2, 16 * 0, 16, 16);
 		} else {
@@ -69,31 +72,31 @@ public class CalculatorHUD extends HUD {
 
 		int padding = 2;
 
-		final int brightness = (int) Math.ceil(Engine.INSTANCE.getHardwareDevice().getDisplayManager().getBrightness() * 9);
+		final int brightness = (int) Math.ceil(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().getBrightness() * 9);
 		if (brightness <= 10) {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * brightness, 16 * 1, 16, 16);
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * brightness, 16 * 1, 16, 16);
 		} else {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Brightness error");
+			WarpPI.getPlatform().getConsoleUtils().out().println(1, "Brightness error");
 		}
 
 		padding += 18 + 6;
 
-		final boolean canGoBack = Engine.INSTANCE.getHardwareDevice().getDisplayManager().canGoBack();
-		final boolean canGoForward = Engine.INSTANCE.getHardwareDevice().getDisplayManager().canGoForward();
+		final boolean canGoBack = WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().canGoBack();
+		final boolean canGoForward = WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().canGoForward();
 
-		if (Engine.getPlatform().getSettings().isDebugEnabled()) {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 18, 16 * 0, 16, 16);
+		if (WarpPI.getPlatform().getSettings().isDebugEnabled()) {
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * 18, 16 * 0, 16, 16);
 			padding += 18 + 6;
 		}
 
 		if (canGoBack && canGoForward) {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 14, 16 * 0, 16, 16);
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * 14, 16 * 0, 16, 16);
 		} else if (canGoBack) {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 15, 16 * 0, 16, 16);
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * 15, 16 * 0, 16, 16);
 		} else if (canGoForward) {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 16, 16 * 0, 16, 16);
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * 16, 16 * 0, 16, 16);
 		} else {
-			r.glFillRect(StaticVars.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 17, 16 * 0, 16, 16);
+			r.glFillRect(ctx.getWidth() - (padding + 16), 2, 16, 16, 16 * 17, 16 * 0, 16, 16);
 		}
 
 		padding += 18;
@@ -101,23 +104,23 @@ public class CalculatorHUD extends HUD {
 		//DRAW BOTTOM
 		r.glDrawStringLeft(2, 90, d.displayDebugString);
 
-		Utils.getFont(true, false).use(engine);
+		Utils.getFont(true, false).use(display);
 		r.glColor4i(255, 0, 0, 40);
-		r.glDrawStringLeft(1 + 1, StaticVars.screenSize[1] - 7 - 7 + 1, "WORK IN");
+		r.glDrawStringLeft(1 + 1, ctx.getHeight() - 7 - 7 + 1, "WORK IN");
 		r.glColor4i(255, 0, 0, 80);
-		r.glDrawStringLeft(1, StaticVars.screenSize[1] - 7 - 7, "WORK IN");
+		r.glDrawStringLeft(1, ctx.getHeight() - 7 - 7, "WORK IN");
 		r.glColor4i(255, 0, 0, 40);
-		r.glDrawStringLeft(1 + 1, StaticVars.screenSize[1] - 7 + 1, "PROGRESS.");
+		r.glDrawStringLeft(1 + 1, ctx.getHeight() - 7 + 1, "PROGRESS.");
 		r.glColor4i(255, 0, 0, 80);
-		r.glDrawStringLeft(1, StaticVars.screenSize[1] - 7, "PROGRESS.");
+		r.glDrawStringLeft(1, ctx.getHeight() - 7, "PROGRESS.");
 		
 		int currentDebugLine = 2;
-		if (Engine.getPlatform().getSettings().isDebugEnabled()) {
+		if (WarpPI.getPlatform().getSettings().isDebugEnabled()) {
 			ObjectArrayList<Screen> allSessions = new ObjectArrayList<>();
-			for (Screen session : Engine.INSTANCE.getHardwareDevice().getDisplayManager().sessions) {
+			for (Screen session : WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().sessions) {
 				allSessions.add(0, session);
 			}
-			Screen curScreen = Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
+			Screen curScreen = WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().getScreen();
 			if (curScreen.historyBehavior == HistoryBehavior.DONT_KEEP_IN_HISTORY) {
 				allSessions.add(curScreen);
 			}
@@ -126,7 +129,7 @@ public class CalculatorHUD extends HUD {
 				if (session != null) {
 					String title = session.getSessionTitle();
 					if (title != null && title.length() > 0) {
-						Utils.getFont(true).use(engine);
+						Utils.getFont(true).use(display);
 						if (session.historyBehavior == HistoryBehavior.DONT_KEEP_IN_HISTORY) {
 							r.glColor(0xFF3333FF);
 						} else if (session.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
@@ -134,28 +137,48 @@ public class CalculatorHUD extends HUD {
 						} else {
 							r.glColor(0xFF990000);
 						}
-						r.glDrawStringLeft(0, StaticVars.screenSize[1] - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "[" + String.format("%1$03d", session.debugScreenID) + "] " + title.toUpperCase());
-						if (session == Engine.INSTANCE.getHardwareDevice().getDisplayManager().getScreen()) {
+						r.glDrawStringLeft(0, ctx.getHeight() - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "[" + String.format("%1$03d", session.debugScreenID) + "] " + title.toUpperCase());
+						if (session == WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().getScreen()) {
 							r.glColor(0xFF00CC00);
 						} else {
 							r.glColor(0xFF990000);
 						}
-						r.glDrawStringLeft(0, StaticVars.screenSize[1] - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "      " + title.toUpperCase());
+						r.glDrawStringLeft(0, ctx.getHeight() - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "      " + title.toUpperCase());
 					}	
 					currentDebugLine++;
 				}
 			}
 			r.glColor(0xFF000000);
-			r.glDrawStringLeft(5, StaticVars.screenSize[1] - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "DEBUG ENABLED");
+			r.glDrawStringLeft(5, ctx.getHeight() - ((currentDebugLine+1) * (r.getCurrentFont().getCharacterHeight()+1)), "DEBUG ENABLED");
 		}
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 		// TODO Auto-generated method stub
 
 	}
 
+	@Override
+	public int getMarginLeft() {
+		return 0;
+	}
+
+	@Override
+	public int getMarginTop() {
+		return 20;
+	}
+
+	@Override
+	public int getMarginRight() {
+		return 0;
+	}
+
+	@Override
+	public int getMarginBottom() {
+		return 0;
+	}
+
 	@Override
 	public void renderBackground() {
 		// TODO Auto-generated method stub

core/src/main/java/it/cavallium/warppi/gui/DisplayManager.java

@@ -1,34 +1,30 @@
 package it.cavallium.warppi.gui;
 
-import java.io.IOException;
-import java.util.Arrays;
-import java.util.LinkedList;
-import java.util.List;
-
-import it.cavallium.warppi.Engine;
-import it.cavallium.warppi.Platform.ConsoleUtils;
 import it.cavallium.warppi.Platform.Semaphore;
-import it.cavallium.warppi.StaticVars;
-import it.cavallium.warppi.device.Keyboard;
-import it.cavallium.warppi.flow.Observable;
-import it.cavallium.warppi.flow.Pair;
-import it.cavallium.warppi.gui.graphicengine.BinaryFont;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
-import it.cavallium.warppi.gui.graphicengine.Renderer;
-import it.cavallium.warppi.gui.graphicengine.RenderingLoop;
-import it.cavallium.warppi.gui.graphicengine.Skin;
-import it.cavallium.warppi.gui.graphicengine.impl.nogui.NoGuiEngine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.BacklightOutputDevice;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+import it.cavallium.warppi.device.input.Keyboard;
+import it.cavallium.warppi.event.*;
+import it.cavallium.warppi.gui.graphicengine.*;
 import it.cavallium.warppi.gui.screens.Screen;
+import it.cavallium.warppi.util.Timer;
 import it.cavallium.warppi.util.Utils;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
+import java.io.IOException;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.function.Consumer;
+
 public final class DisplayManager implements RenderingLoop {
 	private static final int tickDuration = 50;
 
 	private float brightness;
 
-	public final GraphicEngine engine;
-	public final HardwareDisplay monitor;
+	public final DisplayOutputDevice display;
+	public final GraphicEngine graphicEngine;
+	public final BacklightOutputDevice backlight;
 	public final boolean supportsPauses;
 	public Renderer renderer;
 
@@ -51,24 +47,23 @@ public final class DisplayManager implements RenderingLoop {
 	 */
 	public boolean forceRefresh;
 
-	public DisplayManager(final HardwareDisplay monitor, final HUD hud, final Screen screen, final String title) {
-		this.monitor = monitor;
+	public DisplayManager(final DisplayOutputDevice display, final BacklightOutputDevice backlight, final HUD hud, final Screen screen, final String title) {
+		this.display = display;
+		this.graphicEngine = display.getGraphicEngine();
+		this.backlight = backlight;
 		this.hud = hud;
 		initialTitle = title;
 		initialScreen = screen;
 
-		screenChange = Engine.getPlatform().newSemaphore();
-		engine = chooseGraphicEngine();
-		supportsPauses = engine.doesRefreshPauses();
+		screenChange = WarpPI.getPlatform().newSemaphore();
+		supportsPauses = graphicEngine.doesRefreshPauses();
 
-		glyphsHeight = new int[] { 9, 6, 12, 9 };
+		glyphsHeight = new int[]{9, 6, 12, 9};
 		displayDebugString = "";
 		errorMessages = new ObjectArrayList<>();
 	}
 
 	public void initialize() {
-		monitor.initialize();
-
 		try {
 			hud.d = this;
 			hud.create();
@@ -77,96 +72,39 @@ public final class DisplayManager implements RenderingLoop {
 			}
 		} catch (final Exception e) {
 			e.printStackTrace();
-			Engine.getPlatform().exit(0);
+			WarpPI.getPlatform().exit(0);
 		}
 
 		try {
-			engine.create();
-			renderer = engine.getRenderer();
-			engine.setTitle(initialTitle);
+			graphicEngine.create();
+			renderer = graphicEngine.getRenderer();
+			graphicEngine.setTitle(initialTitle);
 			loop();
 		} catch (final Exception ex) {
 			ex.printStackTrace();
 		}
-		monitor.shutdown();
 	}
 
 	/*
-	 * private void load_skin() {
-	 * try {
-	 * skin_tex = glGenTextures();
-	 * glBindTexture(GL_TEXTURE_2D, skin_tex);
-	 * glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+	 * private void load_skin() { try { skin_tex = glGenTextures();
+	 * glBindTexture(GL_TEXTURE_2D, skin_tex); glPixelStorei(GL_UNPACK_ALIGNMENT,
+	 * 1);
 	 *
-	 * InputStream in = new FileInputStream("skin.png");
-	 * PNGDecoder decoder = new PNGDecoder(in);
+	 * InputStream in = new FileInputStream("skin.png"); PNGDecoder decoder = new
+	 * PNGDecoder(in);
 	 *
 	 * System.out.println("width="+decoder.getWidth());
 	 * System.out.println("height="+decoder.getHeight());
 	 *
 	 * ByteBuffer buf =
 	 * ByteBuffer.allocateDirect(4*decoder.getWidth()*decoder.getHeight());
-	 * decoder.decode(buf, decoder.getWidth()*4, Format.RGBA);
-	 * buf.flip();
+	 * decoder.decode(buf, decoder.getWidth()*4, Format.RGBA); buf.flip();
 	 *
-	 * skin = buf;
-	 * skin_w = decoder.getWidth();
-	 * skin_h = decoder.getHeight();
-	 * glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, skin_w,
-	 * skin_h, 0, GL_RGBA, GL_UNSIGNED_BYTE, skin);
-	 * } catch (IOException ex) {
-	 * ex.printStackTrace();
-	 * }
-	 * }
+	 * skin = buf; skin_w = decoder.getWidth(); skin_h = decoder.getHeight();
+	 * glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, skin_w, skin_h, 0, GL_RGBA,
+	 * GL_UNSIGNED_BYTE, skin); } catch (IOException ex) { ex.printStackTrace(); } }
 	 */
 
-	private GraphicEngine chooseGraphicEngine() {
-		GraphicEngine d;
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "framebuffer engine", null);
-		if (d != null && d.isSupported()) {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Using FB Graphic Engine");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "CPU engine", null);
-		if (d != null && d.isSupported()) {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Using CPU Graphic Engine");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "GPU engine", null);
-		if (d != null && d.isSupported()) {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Using GPU Graphic Engine");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "headless 24 bit engine", null);
-		if (d != null && d.isSupported()) {
-			System.err.println("Using Headless 24 bit Engine! This is a problem! No other graphic engines are available.");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "headless 256 colors engine", null);
-		if (d != null && d.isSupported()) {
-			System.err.println("Using Headless 256 Engine! This is a problem! No other graphic engines are available.");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "headless 8 colors engine", null);
-		if (d != null && d.isSupported()) {
-			System.err.println("Using Headless basic Engine! This is a problem! No other graphic engines are available.");
-			return d;
-		}
-		d = Utils.getOrDefault(Engine.getPlatform().getEnginesList(), "HTML5 engine", null);
-		if (d != null && d.isSupported()) {
-			Engine.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_NODEBUG, "Using Html Graphic Engine");
-			return d;
-		}
-		d = new NoGuiEngine();
-		if (d != null && d.isSupported()) {
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Using NoGui Graphic Engine");
-			return d;
-		}
-		throw new UnsupportedOperationException("No graphic engines available.");
-	}
-
-
-
 	public void closeScreen() {
 		boolean isLastSession = sessions[1] == null;
 		if (!isLastSession) {
@@ -186,10 +124,10 @@ public final class DisplayManager implements RenderingLoop {
 			} else {
 				currentSession = 0;
 			}
-			updateCurrentScreen(sessions[currentSession]);	
+			updateCurrentScreen(sessions[currentSession]);
 		}
 	}
-	
+
 	public void setScreen(final Screen screen) {
 		boolean mustBeAddedToHistory = screen.initialized == false;
 		if (!mustBeAddedToHistory) {
@@ -200,34 +138,44 @@ public final class DisplayManager implements RenderingLoop {
 			mustBeAddedToHistory |= !found;
 		}
 		if (mustBeAddedToHistory) {
-			if (screen.historyBehavior == HistoryBehavior.NORMAL || screen.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
+			if (screen.historyBehavior == HistoryBehavior.NORMAL
+				|| screen.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
 				if (currentSession > 0) {
-					final int sl = sessions.length; //TODO: I don't know why if i don't add +5 or more some items disappear
+					final int sl = sessions.length; // TODO: I don't know why if i don't add +5 or more some items
+					// disappear
 					List<Screen> newSessions = new LinkedList<>();
 					int i = 0;
 					for (Screen s : sessions) {
+						if (i == currentSession) {
+							currentSession = newSessions.size();
+							newSessions.add(screen);
+						}
 						if (s != null) {
 							if (i < currentSession) {
-								if (s.historyBehavior != HistoryBehavior.DONT_KEEP_IN_HISTORY)
-									newSessions.add(s);
-							} else {
 								if (s.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
 									newSessions.add(s);
 								}
+							} else {
+								if (s.historyBehavior != HistoryBehavior.DONT_KEEP_IN_HISTORY)
+									newSessions.add(s);
 							}
 						}
 						i++;
 					}
-					sessions = newSessions.toArray(new Screen[5]);
-					currentSession = newSessions.indexOf(screen);
-//					sessions = Arrays.copyOfRange(sessions, currentSession, sl);
+					for (int j = 0; j < sl; j++) {
+						if (j < newSessions.size()) {
+							sessions[j] = newSessions.get(j);
+						} else {
+							sessions[j] = null;
+						}
+					}
 				} else {
 					currentSession = 0;
+					for (int i = sessions.length - 1; i >= 1; i--) {
+						sessions[i] = sessions[i - 1];
+					}
+					sessions[0] = screen;
 				}
-				for (int i = sessions.length - 1; i >= 1; i--) {
-					sessions[i] = sessions[i - 1];
-				}
-				sessions[0] = screen;
 			} else {
 				currentSession = -1;
 			}
@@ -248,13 +196,14 @@ public final class DisplayManager implements RenderingLoop {
 			screenChange.release();
 		} catch (final Exception e) {
 			e.printStackTrace();
-			Engine.getPlatform().exit(0);
+			WarpPI.getPlatform().exit(0);
 		}
 	}
 
 	public void replaceScreen(final Screen screen) {
 		if (screen.initialized == false) {
-			if (screen.historyBehavior == HistoryBehavior.NORMAL || screen.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
+			if (screen.historyBehavior == HistoryBehavior.NORMAL
+				|| screen.historyBehavior == HistoryBehavior.ALWAYS_KEEP_IN_HISTORY) {
 				sessions[currentSession] = screen;
 			} else {
 				currentSession = -1;
@@ -273,7 +222,7 @@ public final class DisplayManager implements RenderingLoop {
 			screenChange.release();
 		} catch (final Exception e) {
 			e.printStackTrace();
-			Engine.getPlatform().exit(0);
+			WarpPI.getPlatform().exit(0);
 		}
 	}
 
@@ -300,7 +249,8 @@ public final class DisplayManager implements RenderingLoop {
 
 	public void goBack() {
 		if (canGoBack()) {
-			if (currentSession >= 0 && screen != sessions[currentSession]) {} else {
+			if (currentSession >= 0 && screen != sessions[currentSession]) {
+			} else {
 				currentSession += 1;
 			}
 			screen = sessions[currentSession];
@@ -350,73 +300,87 @@ public final class DisplayManager implements RenderingLoop {
 	}
 
 	private void load_skin() throws IOException {
-		guiSkin = engine.loadSkin("/skin.png");
+		guiSkin = graphicEngine.loadSkin("/skin.png");
 	}
 
 	private void load_fonts() throws IOException {
 		fonts = new BinaryFont[7];
-		fonts[0] = engine.loadFont("smal");
-		fonts[1] = engine.loadFont("smallest");
-		fonts[2] = engine.loadFont("norm");
-		fonts[3] = engine.loadFont("smal");
-		//4
-		//fonts[5] = engine.loadFont("square");
+		fonts[0] = graphicEngine.loadFont("smal");
+		fonts[1] = graphicEngine.loadFont("smallest");
+		fonts[2] = graphicEngine.loadFont("norm");
+		fonts[3] = graphicEngine.loadFont("smal");
+		// 4
+		// fonts[5] = engine.loadFont("square");
 	}
 
 	private void draw_init() {
-		if (engine.supportsFontRegistering()) {
-			final List<BinaryFont> fontsIterator = engine.getRegisteredFonts();
+		if (graphicEngine.supportsFontRegistering()) {
+			final List<BinaryFont> fontsIterator = graphicEngine.getRegisteredFonts();
 			for (final BinaryFont f : fontsIterator) {
 				if (!f.isInitialized()) {
-					f.initialize(engine);
+					f.initialize(display);
 				}
 			}
 		}
 		if (!screen.graphicInitialized) {
 			try {
-				screen.initializeGraphic();
+				var displaySize = display.getDisplaySize();
+				var scrWidth = displaySize[0] - hud.getMarginLeft() - hud.getMarginRight();
+				var scrHeight = displaySize[1] - hud.getMarginTop() - hud.getMarginBottom();
+				var scrCtx = new ScreenContext(graphicEngine, scrWidth, scrHeight);
+				screen.initializeGraphic(scrCtx);
 			} catch (InterruptedException e) {
 				e.printStackTrace();
 			}
 		}
-		renderer.glClear(engine.getWidth(), engine.getHeight());
+		renderer.glClear(graphicEngine.getWidth(), graphicEngine.getHeight());
 	}
 
 	private void draw_world() {
+		var displaySize = display.getDisplaySize();
+		var scrWidth = displaySize[0] - hud.getMarginLeft() - hud.getMarginRight();
+		var scrHeight = displaySize[1] - hud.getMarginTop() - hud.getMarginBottom();
+		var scrCtx = new RenderContext(graphicEngine, renderer.getBoundedInstance(hud.getMarginLeft(), hud.getMarginTop(), scrWidth, scrHeight), scrWidth, scrHeight);
+		var fullCtx = new RenderContext(graphicEngine, renderer, displaySize[0], displaySize[1]);
+
 		renderer.glColor3i(255, 255, 255);
 
 		if (error != null) {
 			final BinaryFont fnt = Utils.getFont(false, false);
-			if (fnt != null && fnt != engine.getRenderer().getCurrentFont()) {
-				fnt.use(engine);
+			if (fnt != null && fnt != graphicEngine.getRenderer().getCurrentFont()) {
+				fnt.use(display);
 			}
 			renderer.glColor3i(129, 28, 22);
-			renderer.glDrawStringRight(StaticVars.screenSize[0] - 2, StaticVars.screenSize[1] - (fnt.getCharacterHeight() + 2), Engine.getPlatform().getSettings().getCalculatorNameUppercase() + " CALCULATOR");
+			renderer.glDrawStringRight(display.getDisplaySize()[0] - 2,
+				display.getDisplaySize()[1] - (fnt.getCharacterHeight() + 2),
+				WarpPI.getPlatform().getSettings().getCalculatorNameUppercase() + " CALCULATOR");
 			renderer.glColor3i(149, 32, 26);
-			renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, 22, error);
+			renderer.glDrawStringCenter(display.getDisplaySize()[0] / 2, 22, error);
 			renderer.glColor3i(164, 34, 28);
 			int i = 22;
 			for (final String stackPart : errorStackTrace) {
 				renderer.glDrawStringLeft(2, 22 + i, stackPart);
 				i += 11;
 			}
-			if (fonts[0] != null && fonts[0] != engine.getRenderer().getCurrentFont()) {
-				fonts[0].use(engine);
+			if (fonts[0] != null && fonts[0] != graphicEngine.getRenderer().getCurrentFont()) {
+				fonts[0].use(display);
 			}
 			renderer.glColor3i(129, 28, 22);
-			renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, 11, "UNEXPECTED EXCEPTION");
+			renderer.glDrawStringCenter(display.getDisplaySize()[0] / 2, 11, "UNEXPECTED EXCEPTION");
 		} else {
-			if (fonts[0] != null && fonts[0] != engine.getRenderer().getCurrentFont()) {
-				fonts[0].use(engine);
+			if (fonts[0] != null && fonts[0] != graphicEngine.getRenderer().getCurrentFont()) {
+				fonts[0].use(display);
 			}
-			if (hud.visible) hud.renderBackground();
-			screen.render();
+			if (hud.visible)
+				hud.renderBackground();
+			screen.render(scrCtx);
 			if (hud.visible) {
-				hud.render();
+				hud.render(fullCtx);
 				hud.renderTopmostBackground();
 			}
-			screen.renderTopmost();
-			if (hud.visible) hud.renderTopmost();
+			screen.renderTopmost(fullCtx);
+			if (hud.visible)
+				hud.renderTopmost(fullCtx);
 		}
 	}
 
@@ -428,8 +392,8 @@ public final class DisplayManager implements RenderingLoop {
 	private long precTime = -1;
 
 	@Override
-	public void refresh() {
-		if (supportsPauses == false || Keyboard.popRefreshRequest() || forceRefresh || screen.mustBeRefreshed()) {
+	public void refresh(boolean force) {
+		if (force || supportsPauses == false || Keyboard.popRefreshRequest() || forceRefresh || screen.mustBeRefreshed()) {
 			forceRefresh = false;
 			draw();
 		}
@@ -448,42 +412,40 @@ public final class DisplayManager implements RenderingLoop {
 				}
 			} catch (final Exception e) {
 				e.printStackTrace();
-				Engine.getPlatform().exit(0);
+				WarpPI.getPlatform().exit(0);
 			}
 
-			final Observable<Long> workTimer = Observable.interval(DisplayManager.tickDuration);
+			var displayRefreshManager = new DisplayRefreshManager(this::onRefresh);
+			new Timer(DisplayManager.tickDuration, displayRefreshManager::onTick);
+			graphicEngine.onResize().subscribe(displayRefreshManager::onResize);
 
-			final Observable<Integer[]> onResizeObservable = engine.onResize();
-			Observable<Pair<Long, Integer[]>> refreshObservable;
-			if (onResizeObservable == null) {
-				refreshObservable = workTimer.map((l) -> Pair.of(l, null));
-			} else {
-				refreshObservable = Observable.combineChanged(workTimer, engine.onResize());
-			}
-
-			refreshObservable.subscribe((pair) -> {
-				double dt = 0;
-				final long newtime = System.nanoTime();
-				if (precTime == -1) {
-					dt = DisplayManager.tickDuration;
-				} else {
-					dt = (newtime - precTime) / 1000d / 1000d;
-				}
-				precTime = newtime;
-
-				if (pair.getRight() != null) {
-					final Integer[] windowSize = pair.getRight();
-					StaticVars.screenSize[0] = windowSize[0];
-					StaticVars.screenSize[1] = windowSize[1];
-				}
-
-				screen.beforeRender((float) (dt / 1000d));
-			});
-
-			engine.start(getDrawable());
+			graphicEngine.start(getDrawable());
 		} catch (final Exception ex) {
 			ex.printStackTrace();
-		} finally {}
+		} finally {
+		}
+	}
+
+	private void onRefresh(Integer[] windowSize) {
+		double dt = 0;
+		final long newtime = System.nanoTime();
+		if (precTime == -1) {
+			dt = DisplayManager.tickDuration;
+		} else {
+			dt = (newtime - precTime) / 1000d / 1000d;
+		}
+		precTime = newtime;
+
+		if (windowSize != null) {
+			display.getDisplaySize()[0] = windowSize[0];
+			display.getDisplaySize()[1] = windowSize[1];
+		}
+
+		var displaySize = display.getDisplaySize();
+		var scrWidth = displaySize[0] - hud.getMarginLeft() - hud.getMarginRight();
+		var scrHeight = displaySize[1] - hud.getMarginTop() - hud.getMarginBottom();
+		var scrCtx = new ScreenContext(graphicEngine, scrWidth, scrHeight);
+		screen.beforeRender(scrCtx, (float) (dt / 1000d));
 	}
 
 	public void changeBrightness(final float change) {
@@ -493,7 +455,7 @@ public final class DisplayManager implements RenderingLoop {
 	public void setBrightness(final float newval) {
 		if (newval >= 0 && newval <= 1) {
 			brightness = newval;
-			monitor.setBrightness(brightness);
+			backlight.setBrightness(brightness);
 		}
 	}
 
@@ -529,7 +491,31 @@ public final class DisplayManager implements RenderingLoop {
 		renderer.glFillRect(x, y, uvX2 - uvX, uvY2 - uvY, uvX, uvY, uvX2 - uvX, uvY2 - uvY);
 	}
 
-	public void waitForExit() {
-		engine.waitForExit();
+	public Consumer<TouchEvent> getTouchEventListener() {
+		return (TouchEvent t) -> {
+			boolean refresh = false;
+			if (screen != null && screen.initialized && executeTouchEventOnScreen(t, screen)) {
+				refresh = true;
+			} else {
+				//Default behavior
+			}
+			if (refresh) {
+				forceRefresh = true;
+			}
+		};
+	}
+
+	private boolean executeTouchEventOnScreen(TouchEvent t, Screen scr) {
+		if (t instanceof TouchStartEvent) {
+			return scr.onTouchStart((TouchStartEvent) t);
+		} else if (t instanceof TouchMoveEvent) {
+			return scr.onTouchMove((TouchMoveEvent) t);
+		} else if (t instanceof TouchEndEvent) {
+			return scr.onTouchEnd((TouchEndEvent) t);
+		} else if (t instanceof TouchCancelEvent) {
+			return scr.onTouchCancel((TouchCancelEvent) t);
+		} else {
+			throw new UnsupportedOperationException();
+		}
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/DisplayRefreshManager.java

@@ -0,0 +1,27 @@
+package it.cavallium.warppi.gui;
+
+import java.util.Arrays;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Consumer;
+
+public class DisplayRefreshManager {
+	private final Consumer<Integer[]> refreshConsumer;
+	private volatile Integer[] size;
+
+	public DisplayRefreshManager(Consumer<Integer[]> refreshConsumer) {
+		this.refreshConsumer = refreshConsumer;
+	}
+
+	public void onTick() {
+		refreshConsumer.accept(size);
+	}
+
+	public void onResize(Integer[] newSize) {
+		var oldSize = size;
+		if (oldSize == null || !Arrays.equals(oldSize, newSize)) {
+			size = newSize;
+			refreshConsumer.accept(size);
+		}
+	}
+}

core/src/main/java/it/cavallium/warppi/gui/GUIErrorMessage.java

@@ -1,6 +1,6 @@
 package it.cavallium.warppi.gui;
 
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.util.Error;
 
@@ -20,9 +20,9 @@ public class GUIErrorMessage {
 		creationTime = System.currentTimeMillis();
 	}
 
-	public void draw(final GraphicEngine g, final Renderer r, final String msg) {
-		final int scrW = g.getWidth();
-		final int scrH = g.getHeight();
+	public void draw(final DisplayOutputDevice g, final Renderer r, final String msg) {
+		final int scrW = g.getGraphicEngine().getWidth();
+		final int scrH = g.getGraphicEngine().getHeight();
 		final int width = 200;
 		final int height = 20;
 		final int margin = 4;

core/src/main/java/it/cavallium/warppi/gui/GraphicalInterface.java

@@ -5,13 +5,13 @@ public interface GraphicalInterface {
 	
 	void initialize() throws InterruptedException;
 	
-	void initializeGraphic() throws InterruptedException;
+	void initializeGraphic(ScreenContext ctx) throws InterruptedException;
 
-	void render();
+	void render(RenderContext ctx);
 
-	void renderTopmost();
+	void renderTopmost(RenderContext ctx);
 
-	void beforeRender(float dt);
+	void beforeRender(ScreenContext ctx, float dt);
 
 	boolean mustBeRefreshed();
 }

core/src/main/java/it/cavallium/warppi/gui/HUD.java

@@ -1,5 +1,7 @@
 package it.cavallium.warppi.gui;
 
+import it.cavallium.warppi.gui.screens.Screen;
+
 public abstract class HUD implements GraphicalInterface {
 	public DisplayManager d;
 	public boolean created = false;
@@ -18,7 +20,7 @@ public abstract class HUD implements GraphicalInterface {
 	}
 
 	@Override
-	public void initializeGraphic() throws InterruptedException {
+	public void initializeGraphic(ScreenContext ctx) throws InterruptedException {
 		if (!graphicInitialized) {
 			graphicInitialized = true;
 			graphicInitialized();
@@ -42,15 +44,15 @@ public abstract class HUD implements GraphicalInterface {
 	public abstract void renderBackground();
 
 	@Override
-	public abstract void render();
+	public abstract void render(RenderContext ctx);
 
 	public abstract void renderTopmostBackground();
 
 	@Override
-	public abstract void renderTopmost();
+	public abstract void renderTopmost(RenderContext ctx);
 
 	@Override
-	public abstract void beforeRender(float dt);
+	public abstract void beforeRender(ScreenContext ctx, float dt);
 
 	@Override
 	public boolean mustBeRefreshed() {
@@ -65,4 +67,11 @@ public abstract class HUD implements GraphicalInterface {
 		visible = true;
 	}
 
+	public abstract int getMarginLeft();
+
+	public abstract int getMarginTop();
+
+	public abstract int getMarginRight();
+
+	public abstract int getMarginBottom();
 }

core/src/main/java/it/cavallium/warppi/gui/HardwareDisplay.java

@@ -1,9 +0,0 @@
-package it.cavallium.warppi.gui;
-
-public interface HardwareDisplay {
-	void initialize();
-
-	void shutdown();
-
-	void setBrightness(double value);
-}

core/src/main/java/it/cavallium/warppi/gui/RenderContext.java

@@ -0,0 +1,17 @@
+package it.cavallium.warppi.gui;
+
+import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+import it.cavallium.warppi.gui.graphicengine.Renderer;
+
+public class RenderContext extends ScreenContext {
+    private final Renderer renderer;
+
+    public RenderContext(GraphicEngine graphicEngine, Renderer renderer, int width, int height) {
+        super(graphicEngine, width, height);
+        this.renderer = renderer;
+    }
+
+    public Renderer getRenderer() {
+        return renderer;
+    }
+}

core/src/main/java/it/cavallium/warppi/gui/ScreenContext.java

@@ -0,0 +1,27 @@
+package it.cavallium.warppi.gui;
+
+import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+
+public class ScreenContext {
+    private final GraphicEngine graphicEngine;
+    private final int width;
+    private final int height;
+
+    public ScreenContext(GraphicEngine graphicEngine, int width, int height) {
+        this.graphicEngine = graphicEngine;
+        this.width = width;
+        this.height = height;
+    }
+
+    public GraphicEngine getGraphicEngine() {
+        return graphicEngine;
+    }
+
+    public int getWidth() {
+        return width;
+    }
+
+    public int getHeight() {
+        return height;
+    }
+}

core/src/main/java/it/cavallium/warppi/gui/expression/Caret.java

@@ -1,23 +1,28 @@
 package it.cavallium.warppi.gui.expression;
 
+import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
+import it.cavallium.warppi.gui.expression.blocks.BlockOrContainer;
+import it.cavallium.warppi.gui.expression.blocks.BlockPosition;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
 import java.util.Arrays;
 
 public class Caret {
 
-	private int pos;
-	private int remaining;
+	@NotNull
+	private BlockPosition pos;
 	private CaretState state;
 	private final int[] lastSize;
 	private final int[] lastLocation;
 
-	public Caret(final CaretState state, final int pos) {
+	public Caret(final CaretState state, final BlockPosition pos) {
 		this(state, pos, new int[] { 0, 0 }, new int[] { 2, 5 });
 	}
 
-	public Caret(final CaretState state, final int pos, final int[] lastLocation, final int[] lastSize) {
+	public Caret(final CaretState state, final @NotNull BlockPosition pos, final int[] lastLocation, final int[] lastSize) {
 		this.state = state;
 		this.pos = pos;
-		remaining = pos;
 		this.lastLocation = lastLocation;
 		this.lastSize = lastSize;
 	}
@@ -26,26 +31,27 @@ public class Caret {
 	 * Copy
 	 * @param old
 	 */
-	public Caret(Caret old) {
-		this.pos = old.pos;
-		this.remaining = old.remaining;
+	public Caret(Caret old, BlockContainer newRoot) {
+		this.pos = clonePosition(old.pos, newRoot);
 		this.state = old.state;
 		this.lastSize = Arrays.copyOf(old.lastSize, old.lastSize.length);
 		this.lastLocation = Arrays.copyOf(old.lastLocation, old.lastLocation.length);
 	}
 
-	public void skip(final int i) {
-		remaining -= i;
+	private BlockPosition clonePosition(BlockPosition pos, BlockContainer newRoot) {
+		BlockOrContainer el = newRoot;
+		var url = pos.getURL();
+		for (int i : url) {
+			el = el.getAt(i);
+		}
+		return new BlockPosition(el);
 	}
 
-	public int getPosition() {
+	@NotNull
+	public BlockPosition getPos() {
 		return pos;
 	}
 
-	public int getRemaining() {
-		return remaining;
-	}
-
 	public CaretState getState() {
 		return state;
 	}
@@ -64,12 +70,8 @@ public class Caret {
 		}
 	}
 
-	public void setPosition(final int i) {
-		pos = i;
-	}
-
-	public void resetRemaining() {
-		remaining = pos;
+	public void setPosition(final BlockPosition pos) {
+		this.pos = pos;
 	}
 
 	public void setLastLocation(final int x, final int y) {
@@ -90,4 +92,7 @@ public class Caret {
 		return new int[] { lastSize[0], lastSize[1] };
 	}
 
+	public boolean isHere(BlockOrContainer pos) {
+		return getPos().get() == pos;
+	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/ExtraMenu.java

@@ -2,11 +2,12 @@ package it.cavallium.warppi.gui.expression;
 
 import java.util.Arrays;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.event.KeyboardEventListener;
 import it.cavallium.warppi.gui.expression.blocks.Block;
+import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
 import it.cavallium.warppi.gui.expression.blocks.BlockVariable;
 import it.cavallium.warppi.gui.expression.blocks.TreeContainer;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 
 public abstract class ExtraMenu<T extends Block> implements KeyboardEventListener {
@@ -32,7 +33,7 @@ public abstract class ExtraMenu<T extends Block> implements KeyboardEventListene
 	protected int height;
 	protected int[] location;
 
-	public abstract void draw(GraphicEngine ge, Renderer r, Caret caret);
+	public abstract void draw(DisplayOutputDevice ge, Renderer r, Caret caret);
 
 	public abstract void open();
 
@@ -46,7 +47,7 @@ public abstract class ExtraMenu<T extends Block> implements KeyboardEventListene
 		return false;
 	}
 
-	public abstract ExtraMenu<T> clone(final TreeContainer parent, InputContext ic);
+	public abstract ExtraMenu<T> clone(final BlockContainer parent, InputContext ic);
 
 	public abstract ExtraMenu<T> clone(T newBlockVariable);
 

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/Block.java

@@ -1,23 +1,23 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.GraphicalElement;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.ExtraMenu;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.parser.features.interfaces.Feature;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
-public abstract class Block implements TreeBlock, GraphicalElement {
+public abstract class Block implements TreeBlock, BlockOrContainer, GraphicalElement {
 
 	protected boolean small;
 	protected int width;
 	protected int height;
 	protected int line;
-	protected TreeContainer parent;
+	protected BlockContainer parent;
 	
 	public Block() {
 		
@@ -27,7 +27,7 @@ public abstract class Block implements TreeBlock, GraphicalElement {
 	 * Copy
 	 * @param b
 	 */
-	public Block(TreeContainer parent, Block b) {
+	public Block(BlockContainer parent, Block b) {
 		this.small = b.small;
 		this.width = b.width;
 		this.height = b.height;
@@ -43,15 +43,10 @@ public abstract class Block implements TreeBlock, GraphicalElement {
 	 *            Position relative to the window.
 	 * @param y
 	 *            Position relative to the window.
-	 * @param small
 	 */
-	public abstract void draw(GraphicEngine ge, Renderer r, int x, int y, Caret caret);
+	public abstract void draw(DisplayOutputDevice ge, Renderer r, int x, int y, Caret caret);
 
-	public abstract boolean putBlock(Caret caret, Block newBlock);
-
-	public abstract boolean delBlock(Caret caret);
-
-	public abstract BlockReference<?> getBlock(Caret caret);
+	public abstract boolean appendBlock(Caret caret, Block newBlock);
 	
 	/**
 	 * Used only to get inner blocks when deleting the parent block.
@@ -64,8 +59,6 @@ public abstract class Block implements TreeBlock, GraphicalElement {
 	@Override
 	public abstract void recomputeDimensions();
 
-	public abstract int computeCaretMaxBound();
-
 	@Override
 	public int getWidth() {
 		return width;
@@ -81,10 +74,6 @@ public abstract class Block implements TreeBlock, GraphicalElement {
 		return line;
 	}
 
-	public int getCaretDeltaPositionAfterCreation() {
-		return 1;
-	}
-
 	public boolean isSmall() {
 		return small;
 	}
@@ -98,18 +87,66 @@ public abstract class Block implements TreeBlock, GraphicalElement {
 	public abstract Feature toFeature(MathContext context) throws Error;
 
 	@Override
-	public TreeContainer getParentContainer() {
+	public BlockContainer getParentContainer() {
 		return parent;
 	}
 
+	@Override
+	public BlockContainer getParent() {
+		return parent;
+	}
+
+	@Override
+	public BlockOrContainer getAt(int index) {
+		var ic = getInnerContainers();
+		return ic.get(index);
+	}
+
+	@Override
+	public int getIndex() {
+		return parent != null ? parent.getContentUnsafe().indexOf(this) : -1;
+	}
+
 	@Override
 	public boolean hasParent() {
 		return parent != null;
 	}
 
-	public void setParent(final TreeContainer parent) {
+	public void setParent(final BlockContainer parent) {
 		this.parent = parent;
 	}
 	
-	public abstract Block clone(TreeContainer parent, InputContext ic);
+	public abstract Block clone(BlockContainer parent, InputContext ic);
+
+	public BlockReference<?> getReference() {
+		if (this.hasParent()) {
+			return this.parent.getReference(this);
+		} else {
+			return null;
+		}
+	}
+
+	public BlockPosition getLastInnerPosition() {
+		var innerContainers = getInnerContainers();
+		if (innerContainers != null && !innerContainers.isEmpty()) {
+			var lastContainer = innerContainers.get(innerContainers.size() - 1);
+			var content = lastContainer.getContent();
+			if (content.isEmpty()) {
+				return new BlockPosition(lastContainer);
+			} else {
+				return new BlockPosition(content.get(content.size() - 1));
+			}
+		} else {
+			return null;
+		}
+	}
+
+	public BlockPosition getFirstInnerPosition() {
+		var innerContainers = getInnerContainers();
+		if (innerContainers != null && !innerContainers.isEmpty()) {
+			return new BlockPosition(innerContainers.get(0));
+		} else {
+			return null;
+		}
+	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockChar.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.parser.features.FeatureChar;
@@ -23,33 +23,23 @@ public class BlockChar extends Block {
 	 * @param b
 	 * @param ic
 	 */
-	protected BlockChar(final TreeContainer parent, final BlockChar b, InputContext ic) {
+	protected BlockChar(final BlockContainer parent, final BlockChar b, InputContext ic) {
 		super(parent, b);
 		this.ch = b.ch;
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		r.glDrawCharLeft(x, y, ch);
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		return false;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		return false;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return null;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		width = BlockContainer.getDefaultCharWidth(small) - 1;
@@ -67,11 +57,6 @@ public class BlockChar extends Block {
 		return ch;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return 0;
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) {
 		return new FeatureChar(getChar());
@@ -88,7 +73,7 @@ public class BlockChar extends Block {
 	}
 
 	@Override
-	public BlockChar clone(final TreeContainer parent, InputContext ic) {
+	public BlockChar clone(final BlockContainer parent, InputContext ic) {
 		return new BlockChar(parent, this, ic);
 	}
 

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockContainer.java

@@ -1,14 +1,12 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
-import java.util.Arrays;
-
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.GraphicalElement;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.CaretState;
 import it.cavallium.warppi.gui.expression.InputContext;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -17,9 +15,8 @@ import it.cavallium.warppi.math.parser.features.interfaces.Feature;
 import it.cavallium.warppi.util.Error;
 import it.cavallium.warppi.util.Errors;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-import it.unimi.dsi.fastutil.objects.ObjectListIterator;
 
-public class BlockContainer implements TreeContainer, GraphicalElement {
+public class BlockContainer implements TreeContainer, BlockOrContainer, GraphicalElement {
 
 	private static boolean initialized = false;
 
@@ -32,39 +29,39 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 	private int line;
 	public final boolean withBorder;
 	private boolean autoMinimums;
-	private final TreeBlock parent;
+	private final Block parent;
 
 	public BlockContainer() {
 		this(null, false, BlockContainer.getDefaultCharWidth(false), BlockContainer.getDefaultCharHeight(false), true);
 		autoMinimums = true;
 	}
 
-	public BlockContainer(final TreeBlock parent) {
+	public BlockContainer(final Block parent) {
 		this(parent, false, BlockContainer.getDefaultCharWidth(false), BlockContainer.getDefaultCharHeight(false), true);
 		autoMinimums = true;
 	}
 
-	public BlockContainer(final TreeBlock parent, final boolean small) {
+	public BlockContainer(final Block parent, final boolean small) {
 		this(parent, small, BlockContainer.getDefaultCharWidth(small), BlockContainer.getDefaultCharHeight(small), true);
 		autoMinimums = true;
 	}
 
-	public BlockContainer(final TreeBlock parent, final boolean small, final ObjectArrayList<Block> content) {
+	public BlockContainer(final Block parent, final boolean small, final ObjectArrayList<Block> content) {
 		this(parent, small, BlockContainer.getDefaultCharWidth(small), BlockContainer.getDefaultCharHeight(small), content, true);
 		autoMinimums = true;
 	}
 
-	public BlockContainer(final TreeBlock parent, final boolean small, final boolean withBorder) {
+	public BlockContainer(final Block parent, final boolean small, final boolean withBorder) {
 		this(parent, small, BlockContainer.getDefaultCharWidth(small), BlockContainer.getDefaultCharHeight(small), withBorder);
 		autoMinimums = true;
 	}
 
-	public BlockContainer(final TreeBlock parent, final boolean small, final int minWidth, final int minHeight, final boolean withBorder) {
+	public BlockContainer(final Block parent, final boolean small, final int minWidth, final int minHeight, final boolean withBorder) {
 		this(parent, small, minWidth, minHeight, new ObjectArrayList<>(), withBorder);
 		autoMinimums = false;
 	}
 
-	public BlockContainer(final TreeBlock parent, final boolean small, final int minWidth, final int minHeight, final ObjectArrayList<Block> content, final boolean withBorder) {
+	public BlockContainer(final Block parent, final boolean small, final int minWidth, final int minHeight, final ObjectArrayList<Block> content, final boolean withBorder) {
 		this.parent = parent;
 		this.small = small;
 		this.minWidth = minWidth;
@@ -79,7 +76,7 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 		recomputeDimensions();
 	}
 
-	private BlockContainer(final TreeBlock parent, BlockContainer old, InputContext ic) {
+	private BlockContainer(final Block parent, BlockContainer old, InputContext ic) {
 		this.autoMinimums = old.autoMinimums;
 		this.content = new ObjectArrayList<>();
 		for (Block b : old.content) {
@@ -96,15 +93,30 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 		this.withBorder = old.withBorder;
 	}
 	
-	public BlockContainer clone(final TreeBlock parent, InputContext ic) {
+	public BlockContainer clone(final Block parent, InputContext ic) {
 		return new BlockContainer(parent, this, ic);
 	}
 
 	@Override
-	public TreeBlock getParentBlock() {
+	public Block getParentBlock() {
 		return parent;
 	}
 
+	@Override
+	public Block getParent() {
+		return parent;
+	}
+
+	@Override
+	public BlockOrContainer getAt(int index) {
+		return content.get(index);
+	}
+
+	@Override
+	public int getIndex() {
+		return parent != null ? parent.getInnerContainers().indexOf(this) : -1;
+	}
+
 	@Override
 	public boolean hasParent() {
 		return parent != null;
@@ -157,7 +169,7 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 
 	public BlockReference<?> getBlockAt(final int i) {
 		final Block b = content.get(i);
-		return new BlockReference<>(b, i, this);
+		return new BlockReference<>(b, i, content, this);
 	}
 
 	public int getSize() {
@@ -182,10 +194,10 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 	 * @param caret
 	 *            Position of the caret.
 	 */
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		int paddingX = 1;
 
-		if (caret.getRemaining() == 0) {
+		if (caret.isHere(this)) {
 			if (content.size() > 0) {
 				BlockContainer.drawCaret(ge, r, caret, small, x, y + line - content.get(0).line, content.get(0).height);
 			} else {
@@ -201,113 +213,39 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 			r.glDrawLine(x + paddingX, y + height - 1, x + paddingX + width - 1, y + height - 1);
 		} else {
 			for (final Block b : content) {
-				caret.skip(1);
 				b.draw(ge, r, x + paddingX, y + line - b.line, caret);
 				paddingX += b.getWidth();
-				if (caret.getRemaining() == 0) {
+				if (caret.isHere(b)) {
 					BlockContainer.drawCaret(ge, r, caret, small, x + paddingX, y + line - b.line, b.height);
 				}
 				paddingX += 1;
 			}
 		}
-		caret.skip(1);
 	}
 
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
 
-		if (caret.getRemaining() == 0) {
+		if (caret.isHere(this)) {
 			addBlock(0, newBlock);
 			added = true;
 		}
 
 		int pos = 0;
 		for (final Block b : content) {
-			caret.skip(1);
 			pos++;
-			added = added | b.putBlock(caret, newBlock);
-			if (caret.getRemaining() == 0) {
+			added = added | b.appendBlock(caret, newBlock);
+			if (caret.isHere(b)) {
 				addBlock(pos, newBlock);
 				added = true;
 			}
 		}
-		caret.skip(1);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-
-		int pos = 0;
-		for (final Block b : content) {
-			caret.skip(1);
-			pos++;
-			final int deltaCaret = caret.getRemaining();
-			final int caretOldPos = caret.getPosition();
-			removed = removed | b.delBlock(caret);
-			if (caret.getRemaining() == 0 || removed == false && deltaCaret >= 0 && caret.getRemaining() < 0) {
-				ObjectArrayList<Block> blocks = this.getBlockAt(pos - 1).get().getInnerBlocks();
-				ObjectArrayList<BlockContainer> innerContainers = this.getBlockAt(pos - 1).get().getInnerContainers();
-				int innerContainersBeforeCaret = 0;
-				int currentBlockIndex = 0;
-				if (innerContainers != null) {
-					for (BlockContainer c : innerContainers) {
-						currentBlockIndex += c.computeCaretMaxBound();
-						if (currentBlockIndex > deltaCaret) {
-							break;
-						}
-						innerContainersBeforeCaret++;
-					}
-				}
-				// If the caret is at the end of a block with inner containers don't delete anything and enter into that block.
-				if (innerContainers == null || (innerContainers.size() - innerContainersBeforeCaret != 0)) {
-					removeAt(pos - 1);
-					if (blocks != null) {
-						ObjectListIterator<Block> blocksIterator = blocks.iterator();
-						int blockNum = 0;
-						while (blocksIterator.hasNext()) {
-							Block block = blocksIterator.next();
-							addBlockUnsafe(pos - 1 + blockNum, block);
-							blockNum++;
-						}
-					}
-					caret.setPosition(caretOldPos - innerContainersBeforeCaret);
-					removed = true;
-				}
-			}
-		}
-		caret.skip(1);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	public BlockReference<?> getBlock(final Caret caret) {
-		BlockReference<?> block = null;
-
-		int pos = 0;
-		for (final Block b : content) {
-			caret.skip(1);
-			pos++;
-			final int deltaCaret = caret.getRemaining();
-
-			block = b.getBlock(caret);
-			if (block != null) {
-				return block;
-			}
-			if (caret.getRemaining() == 0 || deltaCaret >= 0 && caret.getRemaining() < 0) {
-				block = getBlockAt(pos - 1);
-				return block;
-			}
-		}
-		caret.skip(1);
-		return block;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		int l = 0; //Line
@@ -377,6 +315,10 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 		BlockContainer.initialized = true;
 	}
 
+	public static boolean isInitialized() {
+		return BlockContainer.initialized;
+	}
+
 	public static BinaryFont getDefaultFont(final boolean small) {
 		BlockContainer.checkInitialized();
 		return BlockContainer.defFonts[small ? 1 : 0];
@@ -396,7 +338,7 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 		return BlockContainer.defFontSizes[b ? 3 : 1];
 	}
 
-	public static void drawCaret(final GraphicEngine ge, final Renderer r, final Caret caret, final boolean small,
+	public static void drawCaret(final DisplayOutputDevice ge, final Renderer r, final Caret caret, final boolean small,
 			final int x, final int y, final int height) {
 		if (caret.getState() == CaretState.VISIBLE_ON) {
 			r.glColor(BlockContainer.getDefaultColor());
@@ -424,18 +366,10 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 
 	private static void checkInitialized() {
 		if (!BlockContainer.initialized) {
-			Engine.getPlatform().throwNewExceptionInInitializerError("Please initialize BlockContainer by running the method BlockContainer.initialize(...) first!");
+			WarpPI.getPlatform().throwNewExceptionInInitializerError("Please initialize BlockContainer by running the method BlockContainer.initialize(...) first!");
 		}
 	}
 
-	public int computeCaretMaxBound() {
-		int maxpos = 0;
-		for (final Block b : content) {
-			maxpos += 1 + b.computeCaretMaxBound();
-		}
-		return maxpos + 1;
-	}
-
 	public Function toFunction(final MathContext context) throws Error {
 		final ObjectArrayList<Block> blocks = getContent();
 		final ObjectArrayList<Feature> blockFeatures = new ObjectArrayList<>();
@@ -452,4 +386,22 @@ public class BlockContainer implements TreeContainer, GraphicalElement {
 		return result;
 	}
 
+	public <T extends Block> BlockReference<T> getReference(T block) {
+		var i = content.indexOf(block);
+		if (i < 0) return null;
+		return new BlockReference<>(block, i, content, this);
+	}
+
+	public ObjectArrayList<Block> getContentUnsafe() {
+		return content;
+	}
+
+	public Block getLastBlock() {
+		return content.isEmpty() ? null : content.get(content.size() - 1);
+	}
+
+	public BlockPosition getLastPosition() {
+		var lastBlock = getLastBlock();
+		return lastBlock != null ? new BlockPosition(lastBlock) : new BlockPosition(this);
+	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockDivision.java

@@ -1,15 +1,14 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.parser.features.FeatureDivision;
 import it.cavallium.warppi.math.parser.features.interfaces.Feature;
 import it.cavallium.warppi.util.Error;
-import it.unimi.dsi.fastutil.objects.AbstractObjectList;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 public class BlockDivision extends Block {
@@ -20,14 +19,19 @@ public class BlockDivision extends Block {
 	private int paddingLeftUpper;
 	private int paddingLeftLower;
 	private int h1;
+	private ObjectArrayList<BlockContainer> innerContainers;
 
 	public BlockDivision() {
 		containerUp = new BlockContainer(this, false);
 		containerDown = new BlockContainer(this, false);
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(2);
+		innerContainers.add(containerUp);
+		innerContainers.add(containerDown);
 	}
 
-	private BlockDivision(final TreeContainer parent, BlockDivision old, InputContext ic) {
+	private BlockDivision(final BlockContainer parent, BlockDivision old, InputContext ic) {
 		super(parent, old);
 		containerUp = old.containerUp.clone(this, ic);
 		containerDown = old.containerDown.clone(this, ic);
@@ -35,10 +39,14 @@ public class BlockDivision extends Block {
 		paddingLeftUpper = old.paddingLeftUpper;
 		h1 = old.h1;
 		System.out.println(String.join(",", ""+h1, ""+old.h1, ""+line, ""+old.line));
+
+		innerContainers = new ObjectArrayList<>(2);
+		innerContainers.add(containerUp);
+		innerContainers.add(containerDown);
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		containerUp.draw(ge, r, x + 1 + paddingLeftUpper, y, caret);
@@ -48,38 +56,16 @@ public class BlockDivision extends Block {
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerUp.putBlock(caret, newBlock);
-		added = added | containerDown.putBlock(caret, newBlock);
+		added = added | containerUp.appendBlock(caret, newBlock);
+		added = added | containerDown.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-		removed = removed | containerUp.delBlock(caret);
-		removed = removed | containerDown.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		BlockReference<?> bl = null;
-		bl = containerUp.getBlock(caret);
-		if (bl != null) {
-			return bl;
-		}
-		bl = containerDown.getBlock(caret);
-		return bl;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		final int w1 = containerUp.getWidth();
@@ -120,11 +106,6 @@ public class BlockDivision extends Block {
 		return containerDown;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerUp.computeCaretMaxBound() + containerDown.computeCaretMaxBound();
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) throws Error {
 		final Function upper = getUpperContainer().toFunction(context);
@@ -141,14 +122,11 @@ public class BlockDivision extends Block {
 
 	@Override
 	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(containerUp);
-		output.add(containerDown);
-		return output;
+		return innerContainers;
 	}
 
 	@Override
-	public BlockDivision clone(final TreeContainer parent, InputContext ic) {
+	public BlockDivision clone(final BlockContainer parent, InputContext ic) {
 		return new BlockDivision(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockExponentialNotation.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 
 public class BlockExponentialNotation extends BlockPower {
@@ -18,14 +18,14 @@ public class BlockExponentialNotation extends BlockPower {
 	 * @param old
 	 * @param ic
 	 */
-	private BlockExponentialNotation(final TreeContainer parent, BlockExponentialNotation old, InputContext ic) {
+	private BlockExponentialNotation(final BlockContainer parent, BlockExponentialNotation old, InputContext ic) {
 		super(parent, old, ic);
 		this.bw = old.bw;
 		this.bh = old.bh;
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		r.glDrawStringLeft(x, y + height - bh, "ℯ℮");
@@ -41,7 +41,7 @@ public class BlockExponentialNotation extends BlockPower {
 	}
 	
 	@Override
-	public BlockExponentialNotation clone(final TreeContainer parent, InputContext ic) {
+	public BlockExponentialNotation clone(final BlockContainer parent, InputContext ic) {
 		return new BlockExponentialNotation(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockLogarithm.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -27,11 +27,16 @@ public class BlockLogarithm extends Block implements IParenthesis {
 	private int schh;
 	private int nmbh;
 	private int toph;
+	private ObjectArrayList<BlockContainer> innerContainers;
 
 	public BlockLogarithm() {
 		containerBase = new BlockContainer(this, true);
 		containerNumber = new BlockContainer(this, false);
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(2);
+		innerContainers.add(containerBase);
+		innerContainers.add(containerNumber);
 	}
 
 	public BlockLogarithm(final ObjectArrayList<Block> blocks) {
@@ -40,7 +45,7 @@ public class BlockLogarithm extends Block implements IParenthesis {
 		recomputeDimensions();
 	}
 
-	private BlockLogarithm(final TreeContainer parent, BlockLogarithm old, InputContext ic) {
+	private BlockLogarithm(final BlockContainer parent, BlockLogarithm old, InputContext ic) {
 		super(parent, old);
 		containerBase = old.containerBase.clone(this, ic);
 		containerNumber = old.containerNumber.clone(this, ic);
@@ -56,7 +61,7 @@ public class BlockLogarithm extends Block implements IParenthesis {
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		if (prefix != null) {
@@ -80,38 +85,16 @@ public class BlockLogarithm extends Block implements IParenthesis {
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerBase.putBlock(caret, newBlock);
-		added = added | containerNumber.putBlock(caret, newBlock);
+		added = added | containerBase.appendBlock(caret, newBlock);
+		added = added | containerNumber.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-		removed = removed | containerBase.delBlock(caret);
-		removed = removed | containerNumber.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		BlockReference<?> bl = null;
-		bl = containerBase.getBlock(caret);
-		if (bl != null) {
-			return bl;
-		}
-		bl = containerNumber.getBlock(caret);
-		return bl;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		if (prefix == null) {
@@ -163,11 +146,6 @@ public class BlockLogarithm extends Block implements IParenthesis {
 		return containerNumber;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerBase.computeCaretMaxBound() + containerNumber.computeCaretMaxBound();
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) throws Error {
 		final Function base = getBaseContainer().toFunction(context);
@@ -185,14 +163,11 @@ public class BlockLogarithm extends Block implements IParenthesis {
 
 	@Override
 	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(containerBase);
-		output.add(containerNumber);
-		return output;
+		return innerContainers;
 	}
 
 	@Override
-	public BlockLogarithm clone(final TreeContainer parent, InputContext ic) {
+	public BlockLogarithm clone(final BlockContainer parent, InputContext ic) {
 		return new BlockLogarithm(parent, this, ic);
 	}
 

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockNumericChar.java

@@ -8,12 +8,12 @@ public class BlockNumericChar extends BlockChar {
 		super(ch);
 	}
 
-	private BlockNumericChar(final TreeContainer parent, BlockNumericChar old, InputContext ic) {
+	private BlockNumericChar(final BlockContainer parent, BlockNumericChar old, InputContext ic) {
 		super(parent, old, ic);
 	}
 
 	@Override
-	public BlockNumericChar clone(final TreeContainer parent, InputContext ic) {
+	public BlockNumericChar clone(final BlockContainer parent, InputContext ic) {
 		return new BlockNumericChar(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockOrContainer.java

@@ -0,0 +1,26 @@
+package it.cavallium.warppi.gui.expression.blocks;
+
+import it.cavallium.warppi.gui.GraphicalElement;
+
+public interface BlockOrContainer extends GraphicalElement {
+	BlockOrContainer getParent();
+	BlockOrContainer getAt(int index);
+
+	default void recomputeDimensionsToRoot() {
+		var parent = this;
+		while (parent != null) {
+			parent.recomputeDimensions();
+			parent = parent.getParent();
+		}
+	}
+
+	default BlockContainer getRootContainer() {
+		var parent = this;
+		while (parent != null) {
+			parent = parent.getParent();
+		}
+		return (BlockContainer) parent;
+	}
+
+	int getIndex();
+}

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockParenthesis.java

@@ -9,13 +9,15 @@ import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 public class BlockParenthesis extends BlockParenthesisAbstract {
+	private ObjectArrayList<BlockContainer> innerContainersCached;
+
 	public BlockParenthesis() {}
 
 	public BlockParenthesis(final ObjectArrayList<Block> blocks) {
 		super(blocks);
 	}
 
-	private BlockParenthesis(final TreeContainer parent, BlockParenthesis old, InputContext ic) {
+	private BlockParenthesis(final BlockContainer parent, BlockParenthesis old, InputContext ic) {
 		super(parent, old, ic);
 	}
 
@@ -31,14 +33,7 @@ public class BlockParenthesis extends BlockParenthesisAbstract {
 	}
 
 	@Override
-	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(getNumberContainer());
-		return output;
-	}
-
-	@Override
-	public BlockParenthesis clone(final TreeContainer parent, InputContext ic) {
+	public BlockParenthesis clone(final BlockContainer parent, InputContext ic) {
 		return new BlockParenthesis(parent, this, ic);
 	}
 

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockParenthesisAbstract.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.parser.features.interfaces.Feature;
@@ -14,6 +14,7 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 	private final BlockContainer containerNumber;
 
 	private final String prefix;
+	private final ObjectArrayList<BlockContainer> innerContainers;
 	private int prw;
 	private int chw;
 	private int chh;
@@ -23,12 +24,18 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 		this.prefix = prefix;
 
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
 	public BlockParenthesisAbstract() {
 		containerNumber = new BlockContainer(this, false);
 		prefix = null;
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
 	/**
@@ -36,27 +43,33 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 	 * @param old
 	 * @param ic
 	 */
-	BlockParenthesisAbstract(final TreeContainer parent, BlockParenthesisAbstract old, InputContext ic) {
+	BlockParenthesisAbstract(final BlockContainer parent, BlockParenthesisAbstract old, InputContext ic) {
 		super(parent, old);
 		containerNumber = old.containerNumber.clone(this, ic);
 		prefix = old.prefix;
 		prw = old.prw;
 		chw = old.chw;
 		chh = old.chh;
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
 	public BlockParenthesisAbstract(final ObjectArrayList<Block> blocks) {
 		containerNumber = new BlockContainer(this, false, blocks);
 		prefix = null;
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		if (prefix != null) {
-			r.glDrawStringLeft(x + 1, y + line - chh / 2, prefix);
+			r.glDrawStringLeft(x + 1, y + line - chh / 2f, prefix);
 		}
 		r.glDrawCharLeft(x + prw, y, '╭');
 		r.glDrawCharLeft(x + prw, y + height - chh, '╰');
@@ -73,30 +86,15 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerNumber.putBlock(caret, newBlock);
+		added = added | containerNumber.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-		removed = removed | containerNumber.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return containerNumber.getBlock(caret);
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		if (prefix == null) {
@@ -122,11 +120,6 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 		return containerNumber;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerNumber.computeCaretMaxBound();
-	}
-
 	@Override
 	public abstract Feature toFeature(MathContext context) throws Error;
 
@@ -139,9 +132,7 @@ public abstract class BlockParenthesisAbstract extends Block implements IParenth
 
 	@Override
 	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(containerNumber);
-		return output;
+		return innerContainers;
 	}
 	
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockPosition.java

@@ -0,0 +1,186 @@
+package it.cavallium.warppi.gui.expression.blocks;
+
+import it.unimi.dsi.fastutil.ints.IntArrayList;
+import it.unimi.dsi.fastutil.ints.IntCollections;
+import org.apache.commons.lang3.NotImplementedException;
+
+import java.util.Collections;
+import java.util.Objects;
+
+public final class BlockPosition {
+    private final BlockOrContainer pos;
+
+	public BlockPosition(BlockOrContainer pos) {
+		this.pos = pos;
+	}
+
+	public BlockPosition(Block block) {
+		this.pos = block;
+	}
+
+	public BlockPosition(BlockContainer container) {
+		this.pos = container;
+	}
+
+	public boolean isBlock() {
+		return pos instanceof Block;
+	}
+
+	public boolean isContainer() {
+		return pos instanceof BlockContainer;
+	}
+
+	public Block getBlock() {
+		return (Block) pos;
+	}
+
+	public BlockContainer getContainer() {
+		return (BlockContainer) pos;
+	}
+
+    public BlockOrContainer get() {
+        return pos;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) return true;
+        if (obj == null || obj.getClass() != this.getClass()) return false;
+        var that = (BlockPosition) obj;
+        return Objects.equals(this.pos, that.pos);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(pos);
+    }
+
+    @Override
+    public String toString() {
+        return "BlockPosition[" +
+                "pos=" + pos + ']';
+    }
+
+	public BlockPosition getNext() {
+		if (pos instanceof BlockContainer) {
+			var container = (BlockContainer) pos;
+			var content = container.getContent();
+			if (content.isEmpty()) {
+				BlockContainer nextContainer;
+				if (container.hasParent()) {
+					var containers = container.getParentBlock().getInnerContainers();
+					var it = containers.listIterator(containers.indexOf(container) + 1);
+					nextContainer = it.hasNext() ? it.next() : null;
+				} else {
+					nextContainer = null;
+				}
+				if (nextContainer != null) {
+					return new BlockPosition(nextContainer);
+				} else {
+					var parentBlock = container.getParentBlock();
+					return parentBlock != null ? new BlockPosition(parentBlock) : null;
+				}
+			} else {
+				var targetBlock = content.get(0);
+				var innerContainers = targetBlock.getInnerContainers();
+				if (innerContainers != null && !innerContainers.isEmpty()) {
+					return new BlockPosition(innerContainers.get(0));
+				} else {
+					return new BlockPosition(targetBlock);
+				}
+			}
+		} else if (pos instanceof Block) {
+			var block = (Block) pos;
+			var ref = block.getReference();
+			var nextBlock = ref.getNextBlock();
+			if (nextBlock == null) {
+				var container = block.getParentContainer();
+				BlockContainer nextContainer;
+				if (container.hasParent()) {
+					var containers = container.getParentBlock().getInnerContainers();
+					var it = containers.listIterator(containers.indexOf(container) + 1);
+					nextContainer = it.hasNext() ? it.next() : null;
+				} else {
+					nextContainer = null;
+				}
+				if (nextContainer != null) {
+					return new BlockPosition(nextContainer);
+				} else {
+					var parentBlock = container.getParentBlock();
+					return parentBlock != null ? new BlockPosition(parentBlock) : null;
+				}
+			} else {
+				var targetBlock = nextBlock.get();
+				var innerContainers = targetBlock.getInnerContainers();
+				if (innerContainers != null && !innerContainers.isEmpty()) {
+					return new BlockPosition(innerContainers.get(0));
+				} else {
+					return new BlockPosition(targetBlock);
+				}
+			}
+		} else {
+			throw new UnsupportedOperationException();
+		}
+	}
+
+	public BlockPosition getPrevious() {
+		if (pos instanceof BlockContainer) {
+			var container = (BlockContainer) pos;
+			if (container.hasParent()) {
+				var parentBlock = container.getParentBlock();
+				var innerContainers = parentBlock.getInnerContainers();
+				if (innerContainers != null) {
+					var it = innerContainers.listIterator(innerContainers.indexOf(container));
+					if (it.hasPrevious()) {
+						var prevContainer = it.previous();
+						return prevContainer.getLastPosition();
+					} else {
+						var parentContainer = parentBlock.getParentContainer();
+						var blocks = parentContainer.getContentUnsafe();
+						var bIt = blocks.listIterator(blocks.indexOf(parentBlock));
+						if (bIt.hasPrevious()) {
+							return new BlockPosition(bIt.previous());
+						} else {
+							return new BlockPosition(parentContainer);
+						}
+					}
+				} else {
+					throw new UnsupportedOperationException();
+				}
+			} else {
+				return null;
+			}
+		} else if (pos instanceof Block) {
+			var block = (Block) pos;
+			var innerContainers = block.getInnerContainers();
+			if (innerContainers != null) {
+				var lastContainer = innerContainers.get(innerContainers.size() - 1);
+				return lastContainer.getLastPosition();
+			}
+			var ref = block.getReference();
+			var prevBlock = ref.getPreviousBlock();
+			if (prevBlock == null) {
+				var container = block.getParentContainer();
+				return new BlockPosition(container);
+			} else {
+				var targetBlock = prevBlock.get();
+				return new BlockPosition(targetBlock);
+			}
+		} else {
+			throw new UnsupportedOperationException();
+		}
+	}
+
+	public IntArrayList getURL() {
+		var url = new IntArrayList();
+		var parent = pos;
+		while (parent != null) {
+			var index = parent.getIndex();
+			if (index == -1) break;
+			url.add(index);
+			parent = parent.getParent();
+		}
+		Collections.reverse(url);
+		return url;
+	}
+}

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockPower.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -14,48 +14,40 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 public class BlockPower extends Block {
 
 	private final BlockContainer containerExponent;
+	private final ObjectArrayList<BlockContainer> innerContainers;
 
 	public BlockPower() {
 		containerExponent = new BlockContainer(this, true);
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerExponent);
 	}
 
-	protected BlockPower(final TreeContainer parent, BlockPower old, InputContext ic) {
+	protected BlockPower(final BlockContainer parent, BlockPower old, InputContext ic) {
 		super(parent, old);
 		this.containerExponent = old.containerExponent.clone(this, ic);
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerExponent);
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(true).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		containerExponent.draw(ge, r, x, y, caret);
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerExponent.putBlock(caret, newBlock);
+		added = added | containerExponent.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
-	
-	@Override
-	public boolean delBlock(Caret caret) {
-		boolean removed = false;
-		removed = removed | containerExponent.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return containerExponent.getBlock(caret);
-	}
 
 	@Override
 	public void recomputeDimensions() {
@@ -77,11 +69,6 @@ public class BlockPower extends Block {
 		return containerExponent;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerExponent.computeCaretMaxBound();
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) throws Error {
 		final Function exp = getExponentContainer().toFunction(context);
@@ -95,13 +82,11 @@ public class BlockPower extends Block {
 
 	@Override
 	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(containerExponent);
-		return output;
+		return innerContainers;
 	}
 
 	@Override
-	public BlockPower clone(final TreeContainer parent, InputContext ic) {
+	public BlockPower clone(final BlockContainer parent, InputContext ic) {
 		return new BlockPower(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockPower2.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -14,55 +14,42 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 public class BlockPower2 extends Block {
 
 	private final BlockContainer containerExponent;
+	private final ObjectArrayList<BlockContainer> innerContainers;
 
 	public BlockPower2() {
 		containerExponent = new BlockContainer(this, true);
 		containerExponent.addBlock(0, new BlockNumericChar('2'));
 		recomputeDimensions();
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerExponent);
 	}
 
-	private BlockPower2(final TreeContainer parent, BlockPower2 old, InputContext ic) {
+	private BlockPower2(final BlockContainer parent, BlockPower2 old, InputContext ic) {
 		super(parent, old);
 		this.containerExponent = old.containerExponent.clone(this, ic);
+
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerExponent);
 	}
 
 	@Override
-	public int getCaretDeltaPositionAfterCreation() {
-		return 3;
-	}
-
-	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(true).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		containerExponent.draw(ge, r, x, y, caret);
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerExponent.putBlock(caret, newBlock);
+		added = added | containerExponent.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-		removed = removed | containerExponent.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return containerExponent.getBlock(caret);
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		final int w2 = containerExponent.getWidth();
@@ -83,11 +70,6 @@ public class BlockPower2 extends Block {
 		return containerExponent;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerExponent.computeCaretMaxBound();
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) throws Error {
 		final Function exp = getExponentContainer().toFunction(context);
@@ -101,13 +83,11 @@ public class BlockPower2 extends Block {
 
 	@Override
 	public ObjectArrayList<BlockContainer> getInnerContainers() {
-		ObjectArrayList<BlockContainer> output = new ObjectArrayList<>();
-		output.add(containerExponent);
-		return output;
+		return innerContainers;
 	}
 
 	@Override
-	public BlockPower2 clone(final TreeContainer parent, InputContext ic) {
+	public BlockPower2 clone(final BlockContainer parent, InputContext ic) {
 		return new BlockPower2(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockReference.java

@@ -1,13 +1,17 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+
 public class BlockReference<T extends Block> {
 	private final T block;
 	private final BlockContainer container;
-	private final int blockPosition;
+	private int cachedBlockPosition;
+	private final ObjectArrayList<Block> containerBlocks;
 
-	public BlockReference(final T block, final int blockPosition, final BlockContainer container) {
+	public BlockReference(final T block, final int cachedBlockPosition, final ObjectArrayList<Block> containerBlocks, final BlockContainer container) {
 		this.block = block;
-		this.blockPosition = blockPosition;
+		this.cachedBlockPosition = cachedBlockPosition;
+		this.containerBlocks = containerBlocks;
 		this.container = container;
 	}
 
@@ -20,23 +24,28 @@ public class BlockReference<T extends Block> {
 	}
 
 	public int getIndex() {
-		return blockPosition;
+		if (containerBlocks.size() > cachedBlockPosition && cachedBlockPosition >= 0
+			&& containerBlocks.get(cachedBlockPosition) == block) {
+			return cachedBlockPosition;
+		} else {
+			return cachedBlockPosition = containerBlocks.indexOf(block);
+		}
 	}
 
 	public BlockReference<?> getNextBlock() {
-		return getBlockAtSafe(this.blockPosition + 1);
+		return getBlockAtSafe(getIndex() + 1);
 	}
 
 	public boolean hasNextBlock() {
-		return isInsideBounds(this.blockPosition + 1);
+		return isInsideBounds(getIndex() + 1);
 	}
 
 	public BlockReference<?> getPreviousBlock() {
-		return getBlockAtSafe(this.blockPosition - 1);
+		return getBlockAtSafe(getIndex() - 1);
 	}
 
 	public boolean hasPreviousBlock() {
-		return isInsideBounds(this.blockPosition - 1);
+		return isInsideBounds(getIndex() - 1);
 	}
 
 	private BlockReference<?> getBlockAtSafe(final int i) {

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockSine.java

@@ -13,7 +13,7 @@ public class BlockSine extends BlockParenthesisAbstract {
 		super("SIN");
 	}
 
-	private BlockSine(final TreeContainer parent, BlockSine old, InputContext ic) {
+	private BlockSine(final BlockContainer parent, BlockSine old, InputContext ic) {
 		super(parent, old, ic);
 	}
 
@@ -24,7 +24,7 @@ public class BlockSine extends BlockParenthesisAbstract {
 	}
 
 	@Override
-	public BlockSine clone(final TreeContainer parent, InputContext ic) {
+	public BlockSine clone(final BlockContainer parent, InputContext ic) {
 		return new BlockSine(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockSquareRoot.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -14,22 +14,27 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 public class BlockSquareRoot extends Block {
 
 	private final BlockContainer containerNumber;
+	private final ObjectArrayList<BlockContainer> innerContainers;
 
 	private int h1;
 
 	public BlockSquareRoot() {
 		containerNumber = new BlockContainer(this, false);
 		recomputeDimensions();
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
-	private BlockSquareRoot(final TreeContainer parent, BlockSquareRoot old, InputContext ic) {
+	private BlockSquareRoot(final BlockContainer parent, BlockSquareRoot old, InputContext ic) {
 		super(parent, old);
 		this.containerNumber = old.containerNumber.clone(this, ic);
 		this.h1 = old.h1;
+		innerContainers = new ObjectArrayList<>(1);
+		innerContainers.add(containerNumber);
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		r.glDrawLine(x, y + height - 10 + 1, x, y + height - 10 + 2); // /
@@ -44,30 +49,15 @@ public class BlockSquareRoot extends Block {
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		boolean added = false;
-		added = added | containerNumber.putBlock(caret, newBlock);
+		added = added | containerNumber.appendBlock(caret, newBlock);
 		if (added) {
 			recomputeDimensions();
 		}
 		return added;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		boolean removed = false;
-		removed = removed | containerNumber.delBlock(caret);
-		if (removed) {
-			recomputeDimensions();
-		}
-		return removed;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return containerNumber.getBlock(caret);
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		final int w1 = containerNumber.getWidth();
@@ -93,11 +83,6 @@ public class BlockSquareRoot extends Block {
 		return containerNumber;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return containerNumber.computeCaretMaxBound();
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) throws Error {
 		final Function contnt = getNumberContainer().toFunction(context);
@@ -119,7 +104,7 @@ public class BlockSquareRoot extends Block {
 	}
 
 	@Override
-	public BlockSquareRoot clone(final TreeContainer parent, InputContext ic) {
+	public BlockSquareRoot clone(final BlockContainer parent, InputContext ic) {
 		return new BlockSquareRoot(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockUndefined.java

@@ -1,8 +1,8 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.MathematicalSymbols;
@@ -16,32 +16,22 @@ public class BlockUndefined extends Block {
 		recomputeDimensions();
 	}
 
-	private BlockUndefined(final TreeContainer parent, BlockUndefined old, InputContext ic) {
+	private BlockUndefined(final BlockContainer parent, BlockUndefined old, InputContext ic) {
 		super(parent, old);
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		BlockContainer.getDefaultFont(small).use(ge);
 		r.glColor(BlockContainer.getDefaultColor());
 		r.glDrawStringLeft(x, y, "UNDEFINED");
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		return false;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		return false;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return null;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		width = BlockContainer.getDefaultFont(small).getStringWidth("UNDEFINED");
@@ -55,11 +45,6 @@ public class BlockUndefined extends Block {
 		recomputeDimensions();
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return 0;
-	}
-
 	@Override
 	public Feature toFeature(final MathContext context) {
 		return new FeatureChar(MathematicalSymbols.UNDEFINED);
@@ -76,7 +61,7 @@ public class BlockUndefined extends Block {
 	}
 
 	@Override
-	public BlockUndefined clone(final TreeContainer parent, InputContext ic) {
+	public BlockUndefined clone(final BlockContainer parent, InputContext ic) {
 		return new BlockUndefined(parent, this, ic);
 	}
 

core/src/main/java/it/cavallium/warppi/gui/expression/blocks/BlockVariable.java

@@ -1,15 +1,13 @@
 package it.cavallium.warppi.gui.expression.blocks;
 
-import java.util.Arrays;
-
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.event.KeyReleasedEvent;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.ExtraMenu;
 import it.cavallium.warppi.gui.expression.InputContext;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.functions.Variable.V_TYPE;
@@ -45,7 +43,7 @@ public class BlockVariable extends Block {
 		recomputeDimensions();
 	}
 
-	private BlockVariable(final TreeContainer parent, BlockVariable old, InputContext ic) {
+	private BlockVariable(final BlockContainer parent, BlockVariable old, InputContext ic) {
 		super(parent, old);
 		this.ic = ic;
 		this.ch = old.ch;
@@ -82,7 +80,7 @@ public class BlockVariable extends Block {
 	}
 
 	@Override
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y, final Caret caret) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y, final Caret caret) {
 		if (ic.variableTypeDirtyID != typeDirtyID) {
 			retrieveValue();
 		}
@@ -108,20 +106,10 @@ public class BlockVariable extends Block {
 	}
 
 	@Override
-	public boolean putBlock(final Caret caret, final Block newBlock) {
+	public boolean appendBlock(final Caret caret, final Block newBlock) {
 		return false;
 	}
 
-	@Override
-	public boolean delBlock(final Caret caret) {
-		return false;
-	}
-
-	@Override
-	public BlockReference<?> getBlock(final Caret caret) {
-		return null;
-	}
-
 	@Override
 	public void recomputeDimensions() {
 		width = BlockContainer.getDefaultCharWidth(small);
@@ -139,11 +127,6 @@ public class BlockVariable extends Block {
 		return ch;
 	}
 
-	@Override
-	public int computeCaretMaxBound() {
-		return 0;
-	}
-
 	@Override
 	public ExtraMenu<?> getExtraMenu() {
 		return menu;
@@ -238,9 +221,9 @@ public class BlockVariable extends Block {
 		}
 
 		@Override
-		public void draw(final GraphicEngine ge, final Renderer r, final Caret caret) {
+		public void draw(final DisplayOutputDevice ge, final Renderer r, final Caret caret) {
 			r.glColor3f(1.0f, 1.0f, 1.0f);
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(ge);
+			WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(ge);
 			int popupX = location[0];
 			int popupY = location[1];
 			if (popupX < 0) {
@@ -249,7 +232,7 @@ public class BlockVariable extends Block {
 			if (popupY < 0) {
 				popupY = 0;
 			}
-			final int[] screenSize = ge.getSize();
+			final int[] screenSize = ge.getDisplaySize();
 			if (popupX + width >= screenSize[0]) {
 				popupX = screenSize[0] - width - 1;
 			}
@@ -273,7 +256,7 @@ public class BlockVariable extends Block {
 		}
 
 		@Override
-		public VariableMenu clone(final TreeContainer parent, InputContext ic) {
+		public VariableMenu clone(final BlockContainer parent, InputContext ic) {
 			return new VariableMenu(this, block.clone(parent, ic));
 		}
 
@@ -295,7 +278,7 @@ public class BlockVariable extends Block {
 	}
 	
 	@Override
-	public BlockVariable clone(final TreeContainer parent, InputContext ic) {
+	public BlockVariable clone(final BlockContainer parent, InputContext ic) {
 		return new BlockVariable(parent, this, ic);
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/containers/InlineInputContainer.java

@@ -3,6 +3,7 @@ package it.cavallium.warppi.gui.expression.containers;
 import it.cavallium.warppi.gui.expression.InputContext;
 import it.cavallium.warppi.gui.expression.blocks.Block;
 import it.cavallium.warppi.gui.expression.blocks.BlockChar;
+import it.cavallium.warppi.gui.expression.blocks.BlockNumericChar;
 
 public class InlineInputContainer extends InputContainer {
 
@@ -30,6 +31,21 @@ public class InlineInputContainer extends InputContainer {
 
 	@Override
 	public Block parseChar(final char c) {
-		return new BlockChar(c);
+		switch (c) {
+			case '0':
+			case '1':
+			case '2':
+			case '3':
+			case '4':
+			case '5':
+			case '6':
+			case '7':
+			case '8':
+			case '9':
+			case '.':
+				return new BlockNumericChar(c);
+			default:
+				return new BlockChar(c);
+		}
 	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/containers/InputContainer.java

@@ -1,16 +1,14 @@
 package it.cavallium.warppi.gui.expression.containers;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.event.KeyboardEventListener;
 import it.cavallium.warppi.gui.GraphicalElement;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.CaretState;
 import it.cavallium.warppi.gui.expression.ExtraMenu;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.expression.blocks.Block;
-import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
-import it.cavallium.warppi.gui.expression.blocks.BlockReference;
+import it.cavallium.warppi.gui.expression.blocks.*;
 import it.cavallium.warppi.gui.expression.layouts.InputLayout;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
@@ -22,7 +20,6 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	protected Caret caret;
 	private static final float CARET_DURATION = 0.5f;
 	private float caretTime;
-	private int maxPosition = 0;
 	private boolean parsed = false;
 	private ExtraMenu<?> extra;
 	protected InputContext inputContext;
@@ -49,8 +46,8 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 
 	public InputContainer(final InputContext ic, final boolean small, final int minWidth, final int minHeight) {
 		inputContext = ic;
-		caret = new Caret(CaretState.VISIBLE_ON, 0);
 		root = new BlockContainer(null, small, false);
+		caret = new Caret(CaretState.VISIBLE_ON, new BlockPosition(root));
 	}
 	
 	/**
@@ -61,10 +58,9 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	protected InputContainer(InputContainer old, InputContext ic) {
 		this.caretTime = old.caretTime;
 		this.extra = old.extra == null ? null : old.extra.clone(null, ic);
-		this.maxPosition = old.maxPosition;
-		this.caret = old.caret == null ? null : new Caret(old.caret);
 		this.inputContext = ic;
 		this.root = old.root == null ? null : old.root.clone(null, ic);
+		this.caret = old.caret == null ? null : new Caret(old.caret, root);
 		this.parsed = old.parsed;
 	}
 
@@ -75,10 +71,9 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 
 	public void typeBlock(final Block b) {
 		if (b != null) {
-			caret.resetRemaining();
-			if (root.putBlock(caret, b)) {
-				caret.setPosition(caret.getPosition() + b.getCaretDeltaPositionAfterCreation());
-				maxPosition = root.computeCaretMaxBound();
+			if (root.appendBlock(caret, b)) {
+				var innerPos = b.getFirstInnerPosition();
+				caret.setPosition(innerPos == null ? new BlockPosition(b) : innerPos);
 				root.recomputeDimensions();
 			}
 			closeExtra();
@@ -92,13 +87,65 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void del() {
-		caret.resetRemaining();
-		if (root.delBlock(caret)) {
-			root.recomputeDimensions();
+		var pos = caret.getPos();
+		BlockOrContainer currentElementToRecompute;
+		boolean removed;
+		if (pos.isBlock()) {
+			var block = pos.getBlock();
+			var lastInnerPosition = block.getLastInnerPosition();
+			if (lastInnerPosition != null) {
+				caret.setPosition(lastInnerPosition);
+				currentElementToRecompute = null;
+				removed = false;
+			} else {
+				caret.setPosition(pos.getPrevious());
+				var parent = block.getParentContainer();
+				parent.removeBlockUnsafe(block);
+				currentElementToRecompute = parent;
+				removed = true;
+			}
+		} else if (pos.isContainer()) {
+			var container = pos.getContainer();
+			if (container == root) {
+				currentElementToRecompute = null;
+				removed = false;
+			} else if (!container.hasParent()) {
+				throw new IllegalStateException();
+			} else {
+				var block = container.getParentBlock();
+				var containers = block.getInnerContainers();
+				BlockContainer prevContainer;
+				if (containers == null) {
+					prevContainer = null;
+				} else {
+					var containerIt = containers.listIterator(containers.indexOf(container));
+					if (containerIt.hasPrevious()) {
+						prevContainer = containerIt.previous();
+					} else {
+						prevContainer = null;
+					}
+				}
+				if (prevContainer != null) {
+					var lastPosition = prevContainer.getLastPosition();
+                    caret.setPosition(lastPosition);
+                    currentElementToRecompute = null;
+                    removed = false;
+                } else {
+					caret.setPosition(pos.getPrevious());
+					var parentContainer = block.getParentContainer();
+					parentContainer.removeBlockUnsafe(block);
+					currentElementToRecompute = parentContainer;
+					removed = true;
+				}
+			}
+		} else {
+			throw new UnsupportedOperationException();
 		}
-		if (caret.getPosition() > 0) {
-			caret.setPosition(caret.getPosition() - 1);
-			maxPosition = root.computeCaretMaxBound();
+		if (removed) {
+			while (currentElementToRecompute != null) {
+				currentElementToRecompute.recomputeDimensions();
+				currentElementToRecompute = currentElementToRecompute.getParent();
+			}
 		}
 		caret.turnOn();
 		caretTime = 0;
@@ -106,46 +153,25 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public BlockReference<?> getSelectedBlock() {
-		caret.resetRemaining();
-		final BlockReference<?> selectedBlock = root.getBlock(caret);
-		return selectedBlock;
-	}
-
-	public BlockReference<?> getBlockAtCaretPosition(final int i) {
-		final BlockReference<?> selectedBlock = root.getBlock(new Caret(CaretState.HIDDEN, i));
-		return selectedBlock;
+		var pos = caret.getPos();
+		if (pos.isBlock()) {
+			return pos.getBlock().getReference();
+		} else {
+			var container = pos.getContainer();
+			if (container.hasParent()) {
+				return container.getParentBlock().getReference();
+			} else {
+				return null;
+			}
+		}
 	}
 
 	public void moveLeft() {
-		final int curPos = caret.getPosition();
-		if (curPos > 0) {
-			caret.setPosition(curPos - 1);
+		var prev = caret.getPos().getPrevious();
+		if (prev != null) {
+			caret.setPosition(prev);
 		} else {
-			caret.setPosition(maxPosition - 1);
-		}
-		caret.turnOn();
-		caretTime = 0;
-		closeExtra();
-	}
-
-	public void moveRight(final int delta) {
-		
-		final int curPos = caret.getPosition();
-		if (curPos + delta < maxPosition) {
-			caret.setPosition(curPos + delta);
-		} else {
-			caret.setPosition(0);
-		}
-		caret.turnOn();
-		caretTime = 0;
-		closeExtra();
-	}
-
-	public void moveTo(final int position) {
-		if (position < maxPosition) {
-			caret.setPosition(position);
-		} else {
-			caret.setPosition(0);
+			caret.setPosition(root.getLastPosition());
 		}
 		caret.turnOn();
 		caretTime = 0;
@@ -153,7 +179,22 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void moveRight() {
-		moveRight(1);
+		var prev = caret.getPos().getNext();
+		if (prev != null) {
+			caret.setPosition(prev);
+		} else {
+			caret.setPosition(new BlockPosition(root));
+		}
+		caret.turnOn();
+		caretTime = 0;
+		closeExtra();
+	}
+
+	public void moveTo(final BlockPosition position) {
+		caret.setPosition(position);
+		caret.turnOn();
+		caretTime = 0;
+		closeExtra();
 	}
 
 	@Override
@@ -211,8 +252,7 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	 * @param y
 	 *            Position relative to the window.
 	 */
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y) {
-		caret.resetRemaining();
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y) {
 		root.draw(ge, r, x, y, caret);
 		if (extra != null) {
 			extra.draw(ge, r, caret);
@@ -220,27 +260,13 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void clear() {
-		caret = new Caret(CaretState.VISIBLE_ON, 0);
+		caret = new Caret(CaretState.VISIBLE_ON, new BlockPosition(root));
 		root.clear();
-		maxPosition = root.computeCaretMaxBound();
 		recomputeDimensions();
 	}
 
 	public boolean isEmpty() {
-		return maxPosition <= 1;
-	}
-
-	public int getCaretMaxPosition() {
-		return maxPosition;
-	}
-
-	public void setCaretPosition(final int pos) {
-		if (pos > 0 && pos < maxPosition) {
-			caret.setPosition(pos);
-		}
-		caret.turnOn();
-		caretTime = 0;
-		closeExtra();
+		return root.getSize() == 0;
 	}
 
 	public void setParsed(final boolean parsed) {

core/src/main/java/it/cavallium/warppi/gui/expression/containers/NormalInputContainer.java

@@ -3,22 +3,12 @@ package it.cavallium.warppi.gui.expression.containers;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.CaretState;
 import it.cavallium.warppi.gui.expression.InputContext;
-import it.cavallium.warppi.gui.expression.blocks.Block;
-import it.cavallium.warppi.gui.expression.blocks.BlockChar;
-import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
-import it.cavallium.warppi.gui.expression.blocks.BlockDivision;
-import it.cavallium.warppi.gui.expression.blocks.BlockLogarithm;
-import it.cavallium.warppi.gui.expression.blocks.BlockNumericChar;
-import it.cavallium.warppi.gui.expression.blocks.BlockParenthesis;
-import it.cavallium.warppi.gui.expression.blocks.BlockPower;
-import it.cavallium.warppi.gui.expression.blocks.BlockPower2;
-import it.cavallium.warppi.gui.expression.blocks.BlockReference;
-import it.cavallium.warppi.gui.expression.blocks.BlockSine;
-import it.cavallium.warppi.gui.expression.blocks.BlockSquareRoot;
-import it.cavallium.warppi.gui.expression.blocks.BlockVariable;
-import it.cavallium.warppi.gui.expression.blocks.IParenthesis;
+import it.cavallium.warppi.gui.expression.blocks.*;
 import it.cavallium.warppi.math.MathematicalSymbols;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class NormalInputContainer extends InputContainer {
 
 	@Deprecated()
@@ -43,7 +33,6 @@ public class NormalInputContainer extends InputContainer {
 
 	/**
 	 * Copy
-	 * @param userInput
 	 * @param ic
 	 */
 	public NormalInputContainer(InputContainer old, InputContext ic) {
@@ -106,36 +95,24 @@ public class NormalInputContainer extends InputContainer {
 		switch (c) {
 			case MathematicalSymbols.PARENTHESIS_CLOSE: {
 				final BlockReference<?> ref = getSelectedBlock();
-				if (ref == null) {
+				BlockParenthesisAbstract parenthesis = findParenthesis(ref.get());
+				if (parenthesis == null) {
 					break;
 				} else {
-					final Caret newCaret = new Caret(CaretState.HIDDEN, caret.getPosition());
-					BlockContainer currentContainer;
-					BlockReference<?> newRef = ref;
-					int safeExit = 0;
-					do {
-						currentContainer = (BlockContainer) newRef.get().getParentContainer();
-						final int initialRelativeIndex = currentContainer.getContent().indexOf(newRef.get());
-						final int newIndex = newCaret.getPosition() + currentContainer.getContent().size() - initialRelativeIndex;
-						newRef = getBlockAtCaretPosition(newIndex);
-						newCaret.setPosition(newIndex);
-						safeExit++;
-					} while (newRef != null && newRef.get() instanceof IParenthesis == false && currentContainer != null && safeExit < 100000);
-					if (safeExit >= 100000) {
-						System.err.println("Error 0x001030: Infinite loop");
-					}
-					if (newRef != null) {
-						moveTo(newCaret.getPosition());
-					}
+					moveTo(new BlockPosition(parenthesis));
 				}
 				break;
 			}
+			case MathematicalSymbols.POWER_OF_TWO:
+				moveTo(new BlockPosition(getSelectedBlock().get()));
+				break;
 			case MathematicalSymbols.DIVISION: {
 				@SuppressWarnings("unchecked")
 				final BlockReference<BlockDivision> ref = (BlockReference<BlockDivision>) getSelectedBlock();
 				@SuppressWarnings("unused")
 				final BlockContainer parentContainer = ref.getContainer();
 				BlockReference<?> currentBlock = ref;
+				List<Block> blocksToMove = new ArrayList<>();
 				boolean groupedBefore = false;
 				int before = 0;
 				while (true) {
@@ -148,28 +125,39 @@ public class NormalInputContainer extends InputContainer {
 						if (!groupedBefore) {
 							groupedBefore = true;
 						}
+						blocksToMove.add(b);
 						before++;
 					} else {
 						break;
 					}
 				}
 				if (groupedBefore) {
-					moveLeft();
-					for (int i = 0; i < before; i++) {
-						final BlockReference<?> b = getSelectedBlock();
-						del();
-						moveRight();
-						typeBlock(b.get());
-						moveLeft();
-						moveLeft();
+					var div = ref.get();
+					var upperContainer = div.getUpperContainer();
+					for (int i = blocksToMove.size() - 1; i >= 0; i--) {
+						var b = blocksToMove.get(i);
+						b.getParentContainer().removeBlockUnsafe(b);
+						upperContainer.appendBlock(b);
 					}
-					for (int i = 0; i < before + 1; i++) {
-						moveRight();
-					}
-					moveRight();// Move to the divisor
+					div.recomputeDimensionsToRoot();
+					moveTo(new BlockPosition(div.getLowerContainer()));
 				}
 				break;
 			}
 		}
 	}
+
+	private BlockParenthesisAbstract findParenthesis(Block o) {
+		while (!(o instanceof BlockParenthesisAbstract)) {
+			var pc = o.getParentContainer();
+			if (!pc.hasParent()) {
+				return null;
+			}
+			o = pc.getParentBlock();
+			if (o == null) {
+				return null;
+			}
+		}
+		return (BlockParenthesisAbstract) o;
+	}
 }

core/src/main/java/it/cavallium/warppi/gui/expression/containers/OutputContainer.java

@@ -1,33 +1,40 @@
 package it.cavallium.warppi.gui.expression.containers;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.GraphicalElement;
 import it.cavallium.warppi.gui.expression.Caret;
 import it.cavallium.warppi.gui.expression.CaretState;
 import it.cavallium.warppi.gui.expression.blocks.Block;
 import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
+import it.cavallium.warppi.gui.expression.blocks.BlockPosition;
 import it.cavallium.warppi.gui.expression.layouts.OutputLayout;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 public abstract class OutputContainer implements GraphicalElement, OutputLayout {
 	private static final long serialVersionUID = -5714825964892683571L;
 	public final ObjectArrayList<BlockContainer> roots;
-	private final Caret caret = new Caret(CaretState.HIDDEN, 0);
+	private final Caret caret;
 
 	public OutputContainer() {
 		roots = new ObjectArrayList<>();
-		roots.add(new BlockContainer());
+		var root = new BlockContainer();
+		roots.add(root);
+		caret = new Caret(CaretState.HIDDEN, new BlockPosition(root));
 	}
 
 	public OutputContainer(final boolean small) {
 		roots = new ObjectArrayList<>();
-		roots.add(new BlockContainer(null, small));
+		var root = new BlockContainer(null, small);
+		roots.add(root);
+		caret = new Caret(CaretState.HIDDEN, new BlockPosition(root));
 	}
 
 	public OutputContainer(final boolean small, final int minWidth, final int minHeight) {
 		roots = new ObjectArrayList<>();
-		roots.add(new BlockContainer(null, small));
+		var root = new BlockContainer(null, small);
+		roots.add(root);
+		caret = new Caret(CaretState.HIDDEN, new BlockPosition(root));
 	}
 
 	public void setContentAsSingleGroup(final ObjectArrayList<Block> blocks) {
@@ -119,7 +126,7 @@ public abstract class OutputContainer implements GraphicalElement, OutputLayout
 	 * @param y
 	 *            Position relative to the window.
 	 */
-	public void draw(final GraphicEngine ge, final Renderer r, final int x, final int y) {
+	public void draw(final DisplayOutputDevice ge, final Renderer r, final int x, final int y) {
 		int offset = 0;
 		for (final BlockContainer root : roots) {
 			root.draw(ge, r, x, y + offset, caret);

core/src/main/java/it/cavallium/warppi/gui/graphicengine/GraphicEngine.java

@@ -1,29 +1,32 @@
 package it.cavallium.warppi.gui.graphicengine;
 
+import it.cavallium.warppi.util.EventSubscriber;
+
 import java.io.IOException;
 import java.util.List;
-
-import it.cavallium.warppi.flow.Observable;
+import java.util.function.Consumer;
 
 public interface GraphicEngine {
 
 	int[] getSize();
 
+	boolean isSupported();
+	
 	boolean isInitialized();
 
 	void setTitle(String title);
 
 	void setResizable(boolean r);
 
-	void setDisplayMode(final int ww, final int wh);
+	void setDisplayMode(int ww, int wh);
 
+	void create(Runnable object);
+	
 	default void create() {
 		create(null);
 	};
 
-	void create(Runnable object);
-
-	Observable<Integer[]> onResize();
+	EventSubscriber<Integer[]> onResize();
 
 	int getWidth();
 
@@ -43,10 +46,6 @@ public interface GraphicEngine {
 
 	Skin loadSkin(String file) throws IOException;
 
-	void waitForExit();
-
-	boolean isSupported();
-
 	boolean doesRefreshPauses();
 
 	default boolean supportsFontRegistering() {

core/src/main/java/it/cavallium/warppi/gui/graphicengine/Renderer.java

@@ -1,5 +1,7 @@
 package it.cavallium.warppi.gui.graphicengine;
 
+import it.cavallium.warppi.gui.graphicengine.impl.common.ReboundedRenderer;
+
 public interface Renderer {
 	void glColor3i(int r, int gg, int b);
 
@@ -42,4 +44,8 @@ public interface Renderer {
 	void glClearSkin();
 
 	BinaryFont getCurrentFont();
+
+	default Renderer getBoundedInstance(int dx, int dy, int width, int height) {
+		return new ReboundedRenderer(this, dx, dy, width, height);
+	}
 }

core/src/main/java/it/cavallium/warppi/gui/graphicengine/RenderingLoop.java

@@ -1,5 +1,5 @@
 package it.cavallium.warppi.gui.graphicengine;
 
 public interface RenderingLoop {
-	void refresh();
+	void refresh(boolean force);
 }

core/src/main/java/it/cavallium/warppi/gui/graphicengine/Skin.java

@@ -3,15 +3,17 @@ package it.cavallium.warppi.gui.graphicengine;
 import java.io.IOException;
 import java.net.URISyntaxException;
 
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
+
 public interface Skin {
 
 	void load(String file) throws IOException, URISyntaxException;
 
-	void initialize(GraphicEngine d);
+	void initialize(DisplayOutputDevice d);
 
 	boolean isInitialized();
 
-	void use(GraphicEngine d);
+	void use(DisplayOutputDevice d);
 
 	/**
 	 * May not be available before initialization

core/src/main/java/it/cavallium/warppi/gui/graphicengine/impl/common/PngSkin.java

@@ -3,9 +3,9 @@ package it.cavallium.warppi.gui.graphicengine.impl.common;
 import java.io.File;
 import java.io.IOException;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.Platform.ImageUtils.ImageReader;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.graphicengine.Skin;
 
 public abstract class PngSkin implements Skin {
@@ -25,7 +25,7 @@ public abstract class PngSkin implements Skin {
 		if (!file.startsWith("/")) {
 			file = "/" + file;
 		}
-		final ImageReader r = Engine.getPlatform().getImageUtils().load(Engine.getPlatform().getStorageUtils().getResourceStream(file));
+		final ImageReader r = WarpPI.getPlatform().getImageUtils().load(WarpPI.getPlatform().getPlatformStorage().getResourceStream(file));
 		if (r == null) {
 			skinData = new int[0];
 			skinSize = new int[] { 0, 0 };
@@ -37,7 +37,7 @@ public abstract class PngSkin implements Skin {
 	}
 
 	@Override
-	public void initialize(final GraphicEngine d) {
+	public void initialize(final DisplayOutputDevice d) {
 		// TODO Auto-generated method stub
 
 	}

core/src/main/java/it/cavallium/warppi/gui/graphicengine/impl/common/RFTFont.java

@@ -1,17 +1,13 @@
 package it.cavallium.warppi.gui.graphicengine.impl.common;
 
-import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
-import java.net.URISyntaxException;
 import java.util.LinkedList;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.Platform.ConsoleUtils;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
-import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.util.Utils;
 
 public abstract class RFTFont implements BinaryFont {
@@ -62,7 +58,7 @@ public abstract class RFTFont implements BinaryFont {
 	}
 
 	private void load(final String path, final boolean onlyRaw) throws IOException {
-		Engine.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN + 1, "Loading font " + path);
+		WarpPI.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN + 1, "Loading font " + path);
 		loadFont(path);
 		if (!onlyRaw) {
 			chars32 = new int[intervalsTotalSize * charIntCount];
@@ -94,14 +90,14 @@ public abstract class RFTFont implements BinaryFont {
 			}
 		}
 
-		Engine.getPlatform().gc();
+		WarpPI.getPlatform().gc();
 	}
 
 	private void loadFont(String string) throws IOException {
 		if (!string.startsWith("/")) {
 			string = "/" + string;
 		}
-		InputStream res = Engine.getPlatform().getStorageUtils().getResourceStream(string);
+		InputStream res = WarpPI.getPlatform().getPlatformStorage().getResourceStream(string);
 		final int[] file = Utils.realBytes(Utils.convertStreamToByteArray(res, res.available()));
 		final int filelength = file.length;
 		if (filelength >= 16) {
@@ -140,7 +136,7 @@ public abstract class RFTFont implements BinaryFont {
 					} catch (final Exception ex) {
 						ex.printStackTrace();
 						System.out.println(string);
-						Engine.getPlatform().exit(-1);
+						WarpPI.getPlatform().exit(-1);
 					}
 				}
 			} else {
@@ -266,7 +262,7 @@ public abstract class RFTFont implements BinaryFont {
 	}
 
 	@Override
-	public void initialize(final GraphicEngine d) {}
+	public void initialize(final DisplayOutputDevice d) {}
 
 	@Override
 	public int getStringWidth(final String text) {
@@ -314,7 +310,7 @@ public abstract class RFTFont implements BinaryFont {
 		}
 
 		@Override
-		public void use(final GraphicEngine d) {
+		public void use(final DisplayOutputDevice d) {
 
 		}
 

core/src/main/java/it/cavallium/warppi/gui/graphicengine/impl/common/ReboundedRenderer.java

@@ -0,0 +1,130 @@
+package it.cavallium.warppi.gui.graphicengine.impl.common;
+
+import it.cavallium.warppi.gui.graphicengine.BinaryFont;
+import it.cavallium.warppi.gui.graphicengine.Renderer;
+
+public class ReboundedRenderer implements Renderer {
+	private final Renderer renderer;
+	private final int dx;
+	private final int dy;
+	private final int width;
+	private final int height;
+
+	public ReboundedRenderer(Renderer renderer, int dx, int dy, int width, int height) {
+		this.renderer = renderer;
+		this.dx = dx;
+		this.dy = dy;
+		this.width = width;
+		this.height = height;
+	}
+
+	@Override
+	public void glColor3i(int r, int gg, int b) {
+		renderer.glColor3i(r, gg, b);
+	}
+
+	@Override
+	public void glColor(int c) {
+		renderer.glColor(c);
+	}
+
+	@Override
+	public void glColor4i(int red, int green, int blue, int alpha) {
+		renderer.glColor4i(red, green, blue, alpha);
+	}
+
+	@Override
+	public void glColor3f(float red, float green, float blue) {
+renderer.glColor3f(red, green, blue);
+	}
+
+	@Override
+	public void glColor4f(float red, float green, float blue, float alpha) {
+renderer.glColor4f(red, green, blue, alpha);
+	}
+
+	@Override
+	public void glClearColor4i(int red, int green, int blue, int alpha) {
+renderer.glClearColor4i(red, green, blue, alpha);
+	}
+
+	@Override
+	public void glClearColor4f(float red, float green, float blue, float alpha) {
+renderer.glClearColor4f(red, green, blue, alpha);
+	}
+
+	@Override
+	public int glGetClearColor() {
+		return renderer.glGetClearColor();
+	}
+
+	@Override
+	public void glClearColor(int c) {
+		renderer.glClearColor(c);
+	}
+
+	@Override
+	public void glClear(int screenWidth, int screenHeight) {
+renderer.glClear(screenWidth, screenHeight);
+	}
+
+	@Override
+	public void glDrawLine(float x0, float y0, float x1, float y1) {
+renderer.glDrawLine(this.dx + x0, this.dy + y0, this.dx + x1, this.dy + y1);
+	}
+
+	@Override
+	public void glFillRect(float x, float y, float width, float height, float uvX, float uvY, float uvWidth, float uvHeight) {
+renderer.glFillRect(this.dx + x, this.dy + y, width, height, uvX, uvY, uvWidth, uvHeight);
+	}
+
+	@Override
+	public void glFillColor(float x, float y, float width, float height) {
+renderer.glFillColor(this.dx + x, this.dy + y, width, height);
+	}
+
+	@Override
+	public void glDrawCharLeft(int x, int y, char ch) {
+renderer.glDrawCharLeft(this.dx + x, this.dy + y, ch);
+	}
+
+	@Override
+	public void glDrawCharCenter(int x, int y, char ch) {
+renderer.glDrawCharCenter(this.dx + x, this.dy + y, ch);
+	}
+
+	@Override
+	public void glDrawCharRight(int x, int y, char ch) {
+		renderer.glDrawCharRight(this.dx + x, this.dy + y, ch);
+	}
+
+	@Override
+	public void glDrawStringLeft(float x, float y, String text) {
+		renderer.glDrawStringLeft(this.dx + x, this.dy + y, text);
+	}
+
+	@Override
+	public void glDrawStringCenter(float x, float y, String text) {
+		renderer.glDrawStringCenter(this.dx + x, this.dy + y, text);
+	}
+
+	@Override
+	public void glDrawStringRight(float x, float y, String text) {
+		renderer.glDrawStringRight(this.dx + x, this.dy + y, text);
+	}
+
+	@Override
+	public void glClearSkin() {
+		renderer.glClearSkin();
+	}
+
+	@Override
+	public BinaryFont getCurrentFont() {
+		return renderer.getCurrentFont();
+	}
+
+	@Override
+	public Renderer getBoundedInstance(int dx, int dy, int width, int height) {
+		return renderer.getBoundedInstance(this.dx + dx, this.dy + dy, width, height);
+	}
+}

core/src/main/java/it/cavallium/warppi/gui/graphicengine/impl/nogui/NoGuiEngine.java

@@ -2,19 +2,20 @@ package it.cavallium.warppi.gui.graphicengine.impl.nogui;
 
 import java.io.IOException;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.Platform.Semaphore;
-import it.cavallium.warppi.flow.Observable;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.gui.graphicengine.BinaryFont;
 import it.cavallium.warppi.gui.graphicengine.GraphicEngine;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 import it.cavallium.warppi.gui.graphicengine.RenderingLoop;
 import it.cavallium.warppi.gui.graphicengine.Skin;
+import it.cavallium.warppi.util.EventSubmitter;
+import it.cavallium.warppi.util.EventSubscriber;
 
 public class NoGuiEngine implements GraphicEngine {
 
 	private boolean initialized;
-	public Semaphore exitSemaphore = Engine.getPlatform().newSemaphore(0);
 
 	@Override
 	public int[] getSize() {
@@ -44,7 +45,7 @@ public class NoGuiEngine implements GraphicEngine {
 	}
 
 	@Override
-	public Observable<Integer[]> onResize() {
+	public EventSubscriber<Integer[]> onResize() {
 		return null;
 	}
 
@@ -61,7 +62,6 @@ public class NoGuiEngine implements GraphicEngine {
 	@Override
 	public void destroy() {
 		initialized = false;
-		exitSemaphore.release();
 	}
 
 	@Override
@@ -140,6 +140,11 @@ public class NoGuiEngine implements GraphicEngine {
 			public BinaryFont getCurrentFont() {
 				return null;
 			}
+
+			@Override
+			public Renderer getBoundedInstance(int dx, int dy, int width, int height) {
+				return getRenderer();
+			}
 		};
 	}
 
@@ -147,7 +152,7 @@ public class NoGuiEngine implements GraphicEngine {
 	public BinaryFont loadFont(final String fontName) throws IOException {
 		return new BinaryFont() {
 			@Override
-			public void use(final GraphicEngine d) {}
+			public void use(final DisplayOutputDevice d) {}
 
 			@Override
 			public void load(final String file) throws IOException {}
@@ -158,7 +163,7 @@ public class NoGuiEngine implements GraphicEngine {
 			}
 
 			@Override
-			public void initialize(final GraphicEngine d) {}
+			public void initialize(final DisplayOutputDevice d) {}
 
 			@Override
 			public int getStringWidth(final String text) {
@@ -193,7 +198,7 @@ public class NoGuiEngine implements GraphicEngine {
 	public BinaryFont loadFont(final String path, final String fontName) throws IOException {
 		return new BinaryFont() {
 			@Override
-			public void use(final GraphicEngine d) {}
+			public void use(final DisplayOutputDevice d) {}
 
 			@Override
 			public void load(final String file) throws IOException {}
@@ -204,7 +209,7 @@ public class NoGuiEngine implements GraphicEngine {
 			}
 
 			@Override
-			public void initialize(final GraphicEngine d) {}
+			public void initialize(final DisplayOutputDevice d) {}
 
 			@Override
 			public int getStringWidth(final String text) {
@@ -239,7 +244,7 @@ public class NoGuiEngine implements GraphicEngine {
 	public Skin loadSkin(final String file) throws IOException {
 		return new Skin() {
 			@Override
-			public void use(final GraphicEngine d) {}
+			public void use(final DisplayOutputDevice d) {}
 
 			@Override
 			public void load(final String file) throws IOException {}
@@ -250,7 +255,7 @@ public class NoGuiEngine implements GraphicEngine {
 			}
 
 			@Override
-			public void initialize(final GraphicEngine d) {}
+			public void initialize(final DisplayOutputDevice d) {}
 
 			@Override
 			public int getSkinWidth() {
@@ -266,13 +271,6 @@ public class NoGuiEngine implements GraphicEngine {
 		};
 	}
 
-	@Override
-	public void waitForExit() {
-		try {
-			exitSemaphore.acquire();
-		} catch (final InterruptedException e) {}
-	}
-
 	@Override
 	public boolean isSupported() {
 		return true;

core/src/main/java/it/cavallium/warppi/gui/screens/ChooseVariableValueScreen.java

@@ -1,9 +1,12 @@
 package it.cavallium.warppi.gui.screens;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.StaticVars;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.functions.Variable.VariableValue;
 import it.cavallium.warppi.util.Utils;
@@ -28,29 +31,29 @@ public class ChooseVariableValueScreen extends Screen {
 	public void initialized() throws InterruptedException {}
 
 	@Override
-	public void graphicInitialized() throws InterruptedException {}
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {}
 
 	@Override
-	public void render() {
-		Utils.getFont(false, true).use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor4i(0, 0, 0, 64);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 2 - 20, "WORK IN PROGRESS.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 2 - 20 + 1, "WORK IN PROGRESS.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 2 - 20 + 1, "WORK IN PROGRESS.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3i(255, 0, 0);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 2 - 20, "WORK IN PROGRESS.");
+	public void render(RenderContext ctx) {
+		Utils.getFont(false, true).use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
+		ctx.getRenderer().glColor4i(0, 0, 0, 64);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 2 - 20, "WORK IN PROGRESS.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 2 - 20 + 1, "WORK IN PROGRESS.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 2 - 20 + 1, "WORK IN PROGRESS.");
+		ctx.getRenderer().glColor3i(255, 0, 0);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 2 - 20, "WORK IN PROGRESS.");
 
-		Utils.getFont(false, false).use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor4i(0, 0, 0, 64);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3i(255, 0, 0);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		Utils.getFont(false, false).use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
+		ctx.getRenderer().glColor4i(0, 0, 0, 64);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glColor3i(255, 0, 0);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 
 	}
 

core/src/main/java/it/cavallium/warppi/gui/screens/EmptyScreen.java

@@ -1,6 +1,8 @@
 package it.cavallium.warppi.gui.screens;
 
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 
 public class EmptyScreen extends Screen {
 
@@ -20,16 +22,16 @@ public class EmptyScreen extends Screen {
 	public void initialized() throws InterruptedException {}
 
 	@Override
-	public void graphicInitialized() throws InterruptedException {}
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {}
 
 	@Override
-	public void render() {
+	public void render(RenderContext ctx) {
 		// TODO Auto-generated method stub
 
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 
 	}
 

core/src/main/java/it/cavallium/warppi/gui/screens/KeyboardDebugScreen.java

@@ -1,10 +1,12 @@
 package it.cavallium.warppi.gui.screens;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.StaticVars;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.event.KeyReleasedEvent;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 import it.cavallium.warppi.gui.graphicengine.Renderer;
 
 public class KeyboardDebugScreen extends Screen {
@@ -28,23 +30,23 @@ public class KeyboardDebugScreen extends Screen {
 	public void initialized() throws InterruptedException {}
 
 	@Override
-	public void graphicInitialized() throws InterruptedException {}
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {}
 
 	@Override
-	public void render() {
-		final Renderer renderer = Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer;
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+	public void render(RenderContext ctx) {
+		final Renderer renderer = WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().renderer;
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(0.75f, 0.0f, 0.0f, 1.0f);
-		renderer.glDrawStringRight(StaticVars.screenSize[0] - 10, 30, "-" + keyevent.toUpperCase() + "-");
+		renderer.glDrawStringRight(ctx.getWidth() - 10, 30, "-" + keyevent.toUpperCase() + "-");
 		if (keyevent != "NONE") {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+			WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
 			renderer.glDrawStringLeft(10, 30, "Key position");
 			renderer.glDrawStringLeft(10, 45, "X: " + KeyboardDebugScreen.keyX + ", Y:" + KeyboardDebugScreen.keyY);
 			renderer.glDrawStringLeft(10, 65, "Key value");
 			renderer.glDrawStringLeft(10, 80, key);
 		}
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
 		for (int i = 0; i < 5; i++) {
 			if (KeyboardDebugScreen.log[i] != null) {
@@ -56,10 +58,10 @@ public class KeyboardDebugScreen extends Screen {
 		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
 		renderer.glFillColor(-80 + 100 + 200, 90, 5, 5);
 		renderer.glFillColor(-80 + 100, 100, 200, 70);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
 		renderer.glDrawStringCenter(-80 + 100 + 200 / 2, 100 + 70 / 2 - renderer.getCurrentFont().getCharacterHeight() / 2, "FROM SERIAL");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
 		for (int i = 0; i < 8; i++) {
 			if (KeyboardDebugScreen.pinsA[i] == 1) {
@@ -102,10 +104,10 @@ public class KeyboardDebugScreen extends Screen {
 		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
 		renderer.glFillColor(150 + 90, 200, 5, 5);
 		renderer.glFillColor(150 + 100, 100, 200, 70);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[2].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
 		renderer.glDrawStringCenter(150 + 100 + 200 / 2, 100 + 70 / 2 - renderer.getCurrentFont().getCharacterHeight() / 2, "TO SERIAL");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().fonts[3].use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
 		for (int i = 15; i >= 8; i--) {
 			if (KeyboardDebugScreen.pinsB[i] == 1) {
@@ -176,7 +178,7 @@ public class KeyboardDebugScreen extends Screen {
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 		if (System.currentTimeMillis() - beforetime >= 1000) {
 			keyevent = "NONE";
 			KeyboardDebugScreen.keyX = 0;

core/src/main/java/it/cavallium/warppi/gui/screens/LoadingScreen.java

@@ -1,9 +1,13 @@
 package it.cavallium.warppi.gui.screens;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.StaticVars;
+import it.cavallium.warppi.extra.mario.MarioScreen;
 import it.cavallium.warppi.gui.GraphicUtils;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 
 public class LoadingScreen extends Screen {
 
@@ -21,7 +25,7 @@ public class LoadingScreen extends Screen {
 
 	@Override
 	public void created() throws InterruptedException {
-		Engine.INSTANCE.isLoaded().subscribe((loaded) -> {
+		WarpPI.INSTANCE.isLoaded().subscribe((loaded) -> {
 			this.loaded = loaded;
 		});
 		endLoading = 0;
@@ -29,37 +33,43 @@ public class LoadingScreen extends Screen {
 
 	@Override
 	public void initialized() throws InterruptedException {
-		previousZoomValue = StaticVars.windowZoomFunction.apply(StaticVars.windowZoom.getLastValue());
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().getHUD().hide();
-		StaticVars.windowZoom.onNext(1f);
+		float lastZoomValue = StaticVars.windowZoom.getLastValue();
+		previousZoomValue = lastZoomValue;
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().getHUD().hide();
+		if (lastZoomValue != 1.0f) {
+			StaticVars.windowZoom.submit(1f);
+		}
 	}
 	
 	@Override
-	public void graphicInitialized() throws InterruptedException {}
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 		loadingTextTranslation = GraphicUtils.sinDeg(endLoading * 90f) * 10f;
 
 		endLoading += dt;
-		if (!ended && loaded && (Engine.getPlatform().getSettings().isDebugEnabled() || endLoading >= 3.5f)) {
+		if (!ended && loaded && ((WarpPI.getPlatform().getSettings().isDebugEnabled() && endLoading >= 1.5f) || endLoading >= 3.5f)) {
 			ended = true;
-			StaticVars.windowZoom.onNext(previousZoomValue);
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().getHUD().show();
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(new MathInputScreen());
+			if (previousZoomValue != 1.0f) {
+				StaticVars.windowZoom.submit(previousZoomValue);
+			}
+			WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().getHUD().show();
+			WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(new MathInputScreen());
 		}
 		mustRefresh = true;
 	}
 
 	@Override
-	public void render() {
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3i(255, 255, 255);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(StaticVars.screenSize[0] / 2f - 80, StaticVars.screenSize[1] / 2f - 64, 160, 48, 0, 32, 160, 48);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(StaticVars.screenSize[0] / 2f - 24, StaticVars.screenSize[1] / 2f - loadingTextTranslation, 48, 48, 160, 32, 48, 48);
+	public void render(RenderContext ctx) {
+		DisplayOutputDevice display = d.display;
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(display);
+		ctx.getRenderer().glColor3i(255, 255, 255);
+		ctx.getRenderer().glFillRect(ctx.getWidth() / 2f - 80, ctx.getHeight() / 2f - 64, 160, 48, 0, 32, 160, 48);
+		ctx.getRenderer().glFillRect(ctx.getWidth() / 2f - 24, ctx.getHeight() / 2f - loadingTextTranslation, 48, 48, 160, 32, 48, 48);
 
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(StaticVars.screenSize[0] - 224, StaticVars.screenSize[1] - 48, 224, 48, 0, 80, 224, 48);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glFillRect(StaticVars.screenSize[0] - 160 - 24 - 224, StaticVars.screenSize[1] - 48, 160, 48, 224, 80, 160, 48);
+		ctx.getRenderer().glFillRect(ctx.getWidth() - 224, ctx.getHeight() - 48, 224, 48, 0, 80, 224, 48);
+		ctx.getRenderer().glFillRect(ctx.getWidth() - 160 - 24 - 224, ctx.getHeight() - 48, 160, 48, 224, 80, 160, 48);
 
 	}
 

core/src/main/java/it/cavallium/warppi/gui/screens/MathInputScreen.java

@@ -3,11 +3,13 @@ package it.cavallium.warppi.gui.screens;
 import java.io.IOException;
 import java.util.HashMap;
 
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 import org.apache.commons.lang3.SerializationUtils;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
 import it.cavallium.warppi.Platform.ConsoleUtils;
-import it.cavallium.warppi.device.Keyboard;
+import it.cavallium.warppi.device.input.Keyboard;
 import it.cavallium.warppi.event.Key;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.event.KeyReleasedEvent;
@@ -43,6 +45,7 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 public class MathInputScreen extends Screen {
 
 	private static final BinaryFont fontBig = Utils.getFont(false);
+	private final boolean isCloned;
 
 	public MathContext calc;
 	public InputContext ic;
@@ -62,11 +65,11 @@ public class MathInputScreen extends Screen {
 	public MathInputScreen() {
 		super();
 		historyBehavior = HistoryBehavior.NORMAL;
+		isCloned = false;
 	}
 
 	/**
 	 * Create a copy of this element
-	 * @param mathInputScreen
 	 */
 	private MathInputScreen(MathInputScreen old) {
 		this.calc = new MathContext(old.calc);
@@ -80,6 +83,7 @@ public class MathInputScreen extends Screen {
 		this.mustRefresh = old.mustRefresh;
 		this.result = new NormalOutputContainer(old.result);
 		this.userInput = new NormalInputContainer(old.userInput, this.ic);
+		this.isCloned = true;
 	}
 
 	@Override
@@ -87,16 +91,6 @@ public class MathInputScreen extends Screen {
 		ic = new InputContext();
 		calc = new MathContext();
 
-		try {
-			BlockContainer.initializeFonts(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("norm"), Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.loadFont("smal"));
-		} catch (final IOException e) {
-			e.printStackTrace();
-			Engine.getPlatform().exit(1);
-		}
-
-		userInput = new NormalInputContainer(ic);
-		result = new NormalOutputContainer();
-
 		calc.init();
 	}
 
@@ -106,20 +100,34 @@ public class MathInputScreen extends Screen {
 	}
 
 	@Override
-	public void graphicInitialized() throws InterruptedException {
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {
 		/* Fine caricamento */
+		try {
+			if (!BlockContainer.isInitialized()) {
+				BlockContainer.initializeFonts(ctx.getGraphicEngine().loadFont("norm"), ctx.getGraphicEngine().loadFont("smal"));
+			}
+		} catch (final IOException e) {
+			e.printStackTrace();
+			WarpPI.getPlatform().exit(1);
+		}
+
+		if (!isCloned) {
+			userInput = new NormalInputContainer(ic);
+			result = new NormalOutputContainer();
+		}
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
-		if (Engine.INSTANCE.getHardwareDevice().getDisplayManager().error == null) {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glClearColor(0xFFc5c2af);
+	public void beforeRender(final ScreenContext ctx, final float dt) {
+		if (WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error == null) {
+			ctx.getGraphicEngine().getRenderer().glClearColor(0xFFc5c2af);
 		} else {
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glClearColor(0xFFDC3C32);
-		}
-		if (userInput.beforeRender(dt)) {
-			mustRefresh = true;
+			ctx.getGraphicEngine().getRenderer().glClearColor(0xFFDC3C32);
 		}
+		if (userInput != null)
+			if (userInput.beforeRender(dt)) {
+				mustRefresh = true;
+			}
 		if (computingResult) {
 			computingElapsedTime += dt;
 			computingAnimationElapsedTime += dt;
@@ -140,14 +148,14 @@ public class MathInputScreen extends Screen {
 	}
 
 	@Override
-	public void render() {
-		final Renderer renderer = Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer;
-		MathInputScreen.fontBig.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+	public void render(RenderContext ctx) {
+		final Renderer renderer = ctx.getRenderer();
+		MathInputScreen.fontBig.use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		final int textColor = 0xFF000000;
 		final int padding = 4;
 		renderer.glColor(textColor);
 
-		userInput.draw(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine, renderer, padding, padding + 20);
+		userInput.draw(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display, renderer, padding, padding);
 
 		if (computingResult) {
 			renderer.glColor3f(1, 1, 1);
@@ -156,20 +164,20 @@ public class MathInputScreen extends Screen {
 			final int size = 32;
 			final int posY = computingAnimationIndex % 2;
 			final int posX = (computingAnimationIndex - posY) / 2;
-			renderer.glFillRect(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth() - size - 4, Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - size - 4, size, size, leftX + size * posX, leftY + size * posY, size, size);
+			renderer.glFillRect(ctx.getWidth() - size - 4, ctx.getHeight() - size - 4, size, size, leftX + size * posX, leftY + size * posY, size, size);
 			if (computingBreakTipVisible) {
-				Utils.getFont(false).use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+				Utils.getFont(false).use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 				renderer.glColor3f(0.75f, 0, 0);
-				renderer.glDrawStringRight(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth() - 4 - size - 4, Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - size / 2 - renderer.getCurrentFont().getCharacterHeight() / 2 - 4, "Press (=) to stop");
+				renderer.glDrawStringRight(ctx.getWidth() - 4 - size - 4, ctx.getHeight() - size / 2 - renderer.getCurrentFont().getCharacterHeight() / 2 - 4, "Press (=) to stop");
 			}
 		} else if (!result.isContentEmpty()) {
-			result.draw(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine, renderer, Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getWidth() - result.getWidth() - 2, Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine.getHeight() - result.getHeight() - 2);
+			result.draw(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display, renderer, ctx.getWidth() - result.getWidth() - 2, ctx.getHeight() - result.getHeight() - 2);
 		}
 	}
 
 	@Override
-	public void renderTopmost() {
-		final Renderer renderer = Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer;
+	public void renderTopmost(RenderContext ctx) {
+		final Renderer renderer = ctx.getRenderer();
 		renderer.glColor3f(1, 1, 1);
 		final int pos = 2;
 		final int spacersNumb = 1;
@@ -179,7 +187,7 @@ public class MathInputScreen extends Screen {
 		} else {
 			skinN = 21;
 		}
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(Engine.INSTANCE.getHardwareDevice().getDisplayManager().engine);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().guiSkin.use(WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().display);
 		renderer.glFillRect(2 + 18 * pos + 2 * spacersNumb, 2, 16, 16, 16 * skinN, 16 * 0, 16, 16);
 	}
 
@@ -195,7 +203,7 @@ public class MathInputScreen extends Screen {
 
 	@Override
 	public boolean onKeyPressed(final KeyPressedEvent k) {
-		Engine.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, "MathInputScreen", "Pressed key " + k.getKey().toString());
+		WarpPI.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, "MathInputScreen", "Pressed key " + k.getKey().toString());
 		try {
 			switch (k.getKey()) {
 				case OK:
@@ -347,9 +355,9 @@ public class MathInputScreen extends Screen {
 								userInput.clear();
 								result.clear();
 								currentStep = 0;
-								if (Engine.INSTANCE.getHardwareDevice().getDisplayManager().error != null) {
-									Engine.getPlatform().getConsoleUtils().out().println(1, "Resetting after error...");
-									Engine.INSTANCE.getHardwareDevice().getDisplayManager().error = null;
+								if (WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error != null) {
+									WarpPI.getPlatform().getConsoleUtils().out().println(1, "Resetting after error...");
+									WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error = null;
 								}
 								return true;
 							case SURD_MODE:
@@ -361,7 +369,7 @@ public class MathInputScreen extends Screen {
 								}
 								return true;
 							case debug1:
-								Engine.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(new EmptyScreen());
+								WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(new EmptyScreen());
 								return true;
 							case HISTORY_BACK:
 								//					if (Engine.INSTANCE.getHardwareDevice().getDisplayManager().canGoBack()) {
@@ -428,7 +436,7 @@ public class MathInputScreen extends Screen {
 	@SuppressWarnings("unchecked")
 	private void swapInputScreen() {
 		MathInputScreen mis = new MathInputScreen(this);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(mis);
+		WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(mis);
 	}
 
 	@SuppressWarnings("unused")
@@ -517,10 +525,10 @@ public class MathInputScreen extends Screen {
 		if (!step) {
 			currentStep = 0;
 		}
-		if (Engine.INSTANCE.getHardwareDevice().getDisplayManager().error != null) {
+		if (WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error != null) {
 			//TODO: make the error management a global API rather than being relegated to this screen.
-			Engine.getPlatform().getConsoleUtils().out().println(1, "Resetting after error...");
-			Engine.INSTANCE.getHardwareDevice().getDisplayManager().error = null;
+			WarpPI.getPlatform().getConsoleUtils().out().println(1, "Resetting after error...");
+			WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error = null;
 			calc.f = null;
 			calc.f2 = null;
 			calc.resultsCount = 0;
@@ -540,13 +548,21 @@ public class MathInputScreen extends Screen {
 								calc.f2.clear();
 							}
 							calc.f.add(expr);
-							Engine.getPlatform().getConsoleUtils().out().println(2, "INPUT: " + expr);
+							WarpPI.getPlatform().getConsoleUtils().out().println(2, "INPUT: " + expr);
 							final MathSolver ms = new MathSolver(expr);
 							final ObjectArrayList<ObjectArrayList<Function>> resultSteps = ms.solveAllSteps();
 							resultSteps.add(0, Utils.newArrayList(expr));
+							int stepNumber = 0;
+							for (ObjectArrayList<Function> resultStep : resultSteps) {
+								stepNumber++;
+								WarpPI.getPlatform().getConsoleUtils().out().println(0, "STEP " + stepNumber);
+								for (Function function : resultStep) {
+									WarpPI.getPlatform().getConsoleUtils().out().println(0, " :: " + function.toString());
+								}
+							}
 							final ObjectArrayList<Function> resultExpressions = resultSteps.get(resultSteps.size() - 1);
 							for (final Function rr : resultExpressions) {
-								Engine.getPlatform().getConsoleUtils().out().println(0, "RESULT: " + rr.toString());
+								WarpPI.getPlatform().getConsoleUtils().out().println(0, "RESULT: " + rr.toString());
 							}
 							final ObjectArrayList<ObjectArrayList<Block>> resultBlocks = MathParser.parseOutput(calc, resultExpressions);
 							result.setContentAsMultipleGroups(resultBlocks);
@@ -559,22 +575,22 @@ public class MathInputScreen extends Screen {
 							}
 						}
 					} catch (final InterruptedException ex) {
-						Engine.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, "Computing thread stopped.");
+						WarpPI.getPlatform().getConsoleUtils().out().println(ConsoleUtils.OUTPUTLEVEL_DEBUG_MIN, "Computing thread stopped.");
 					} catch (final Exception ex) {
-						if (Engine.getPlatform().getSettings().isDebugEnabled()) {
+						if (WarpPI.getPlatform().getSettings().isDebugEnabled()) {
 							ex.printStackTrace();
 						}
 						throw new Error(Errors.SYNTAX_ERROR);
 					}
 				} catch (final Error e) {
-					d.errorStackTrace = Engine.getPlatform().stacktraceToString(e);
-					Engine.INSTANCE.getHardwareDevice().getDisplayManager().error = e.id.toString();
+					d.errorStackTrace = WarpPI.getPlatform().stacktraceToString(e);
+					WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().error = e.id.toString();
 					System.err.println(e.id);
 				}
 				computingResult = false;
 			});
-			Engine.getPlatform().setThreadName(computingThread, "Computing Thread");
-			Engine.getPlatform().setThreadDaemon(computingThread);
+			WarpPI.getPlatform().setThreadName(computingThread, "Computing Thread");
+			WarpPI.getPlatform().setThreadDaemon(computingThread);
 			computingThread.setPriority(Thread.NORM_PRIORITY + 3);
 			computingThread.start();
 			return true;
@@ -638,9 +654,9 @@ public class MathInputScreen extends Screen {
 			boolean cancelled = false;
 			for (final Function f : knownVarsInFunctions) {
 				final ChooseVariableValueScreen cvs = new ChooseVariableValueScreen(this, new VariableValue((Variable) f, new Number(calc, 0)));
-				Engine.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(cvs);
+				WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().setScreen(cvs);
 				try {
-					Engine.INSTANCE.getHardwareDevice().getDisplayManager().screenChange.acquire();
+					WarpPI.INSTANCE.getHardwareDevice().getDisplayManager().screenChange.acquire();
 				} catch (final InterruptedException e) {}
 				if (cvs.resultNumberValue == null) {
 					cancelled = true;
@@ -661,9 +677,9 @@ public class MathInputScreen extends Screen {
 				}
 			}
 		});
-		Engine.getPlatform().setThreadName(ct, "Variables user-input queue thread");
+		WarpPI.getPlatform().setThreadName(ct, "Variables user-input queue thread");
 		ct.setPriority(Thread.MIN_PRIORITY);
-		Engine.getPlatform().setThreadDaemon(ct);
+		WarpPI.getPlatform().setThreadDaemon(ct);
 		ct.start();
 	}
 

core/src/main/java/it/cavallium/warppi/gui/screens/Screen.java

@@ -2,9 +2,7 @@ package it.cavallium.warppi.gui.screens;
 
 import it.cavallium.warppi.event.KeyboardEventListener;
 import it.cavallium.warppi.event.TouchEventListener;
-import it.cavallium.warppi.gui.DisplayManager;
-import it.cavallium.warppi.gui.GraphicalInterface;
-import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.*;
 
 public abstract class Screen implements KeyboardEventListener, TouchEventListener, GraphicalInterface {
 	public DisplayManager d;
@@ -21,10 +19,10 @@ public abstract class Screen implements KeyboardEventListener, TouchEventListene
 	}
 
 	@Override
-	public void initializeGraphic() throws InterruptedException {
+	public void initializeGraphic(ScreenContext ctx) throws InterruptedException {
 		if (!graphicInitialized) {
 			graphicInitialized = true;
-			graphicInitialized();
+			graphicInitialized(ctx);
 		}
 	}
 	
@@ -66,18 +64,18 @@ public abstract class Screen implements KeyboardEventListener, TouchEventListene
 	 * Called before initialized()
 	 * @throws InterruptedException
 	 */
-	public abstract void graphicInitialized() throws InterruptedException;
+	public abstract void graphicInitialized(ScreenContext ctx) throws InterruptedException;
 
 	@Override
-	public abstract void render();
+	public abstract void render(RenderContext ctx);
 
 	@Override
-	public void renderTopmost() {
+	public void renderTopmost(RenderContext ctx) {
 
 	}
 
 	@Override
-	public abstract void beforeRender(float dt);
+	public abstract void beforeRender(ScreenContext ctx, float dt);
 
 	@Override
 	public abstract boolean mustBeRefreshed();

core/src/main/java/it/cavallium/warppi/gui/screens/SolveForXScreen.java

@@ -1,9 +1,12 @@
 package it.cavallium.warppi.gui.screens;
 
-import it.cavallium.warppi.Engine;
+import it.cavallium.warppi.WarpPI;
+import it.cavallium.warppi.device.display.DisplayOutputDevice;
 import it.cavallium.warppi.StaticVars;
 import it.cavallium.warppi.event.KeyPressedEvent;
 import it.cavallium.warppi.gui.HistoryBehavior;
+import it.cavallium.warppi.gui.RenderContext;
+import it.cavallium.warppi.gui.ScreenContext;
 
 public class SolveForXScreen extends Screen {
 
@@ -24,20 +27,21 @@ public class SolveForXScreen extends Screen {
 	public void initialized() throws InterruptedException {}
 
 	@Override
-	public void graphicInitialized() throws InterruptedException {}
+	public void graphicInitialized(ScreenContext ctx) throws InterruptedException {}
 
 	@Override
-	public void render() {
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor4i(0, 0, 0, 64);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2 + 1, StaticVars.screenSize[1] / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glColor3i(255, 0, 0);
-		Engine.INSTANCE.getHardwareDevice().getDisplayManager().renderer.glDrawStringCenter(StaticVars.screenSize[0] / 2, StaticVars.screenSize[1] / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+	public void render(RenderContext ctx) {
+		DisplayOutputDevice display = d.display;
+		ctx.getRenderer().glColor4i(0, 0, 0, 64);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2 + 1, ctx.getHeight() / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		ctx.getRenderer().glColor3i(255, 0, 0);
+		ctx.getRenderer().glDrawStringCenter(ctx.getWidth() / 2, ctx.getHeight() / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
 	}
 
 	@Override
-	public void beforeRender(final float dt) {
+	public void beforeRender(ScreenContext ctx, final float dt) {
 
 	}
 

core/src/main/java/it/cavallium/warppi/math/Function.java

@@ -1,6 +1,12 @@
 package it.cavallium.warppi.math;
 
 import it.cavallium.warppi.gui.expression.blocks.Block;
+import it.cavallium.warppi.math.functions.*;
+import it.cavallium.warppi.math.functions.Number;
+import it.cavallium.warppi.math.functions.equations.Equation;
+import it.cavallium.warppi.math.functions.equations.EquationsSystem;
+import it.cavallium.warppi.math.functions.equations.EquationsSystemPart;
+import it.cavallium.warppi.math.functions.trigonometry.*;
 import it.cavallium.warppi.math.rules.Rule;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
@@ -15,6 +21,16 @@ public interface Function {
 	@Override
 	String toString();
 
+	/**
+	 * Indicates whether some other object is a <code>Function</code> which is <em>identical</em> to this one.
+	 * <p>
+	 * Two functions which are not identical, but only equivalent (due to, for example, the commutative property) aren't
+	 * considered equal.
+	 *
+	 * @param o the other object to compare.
+	 * @return <code>true</code> if the other object is identical to this <code>Function</code>, <code>false</code>
+	 * otherwise.
+	 */
 	@Override
 	boolean equals(Object o);
 
@@ -28,7 +44,7 @@ public interface Function {
 	/**
 	 * Deep clone this function, also change mathContext.
 	 *
-	 * @param mathContext new mathContext
+	 * @param newMathContext new mathContext
 	 * @return A clone of this function.
 	 */
 	Function clone(MathContext newMathContext);
@@ -80,4 +96,49 @@ public interface Function {
 	 * @throws Error
 	 */
 	ObjectArrayList<Block> toBlock(MathContext context) throws Error;
+
+	/**
+	 * Accepts a {@code Function.Visitor<Argument, Result>} by calling the correct overload of <code>visit</code>.
+	 *
+	 * @param visitor    The visitor to be accepted.
+	 * @param argument   An additional argument to be passed to <code>visit</code>.
+	 * @param <Argument> The type of an additional argument to be passed to the <code>visit</code> method.
+	 * @param <Result>   The return type of the <code>visit</code> method.
+	 * @return The value returned by <code>visit</code>.
+	 */
+	<Argument, Result> Result accept(Visitor<Argument, Result> visitor, Argument argument);
+
+	/**
+	 * Executes a different overload of a method for each <code>Function</code> implementation.
+	 *
+	 * @param <Argument> The type of an additional argument which can be passed to all <code>visit</code> method overloads.
+	 *                   If the argument is not required, this type parameter should be set to {@link Void}.
+	 * @param <Result>   The return type of all <code>visit</code> method overloads.
+	 */
+	interface Visitor<Argument, Result> {
+		Result visit(ArcCosine arcCosine, Argument argument);
+		Result visit(ArcSine arcSine, Argument argument);
+		Result visit(ArcTangent arcTangent, Argument argument);
+		Result visit(Cosine cosine, Argument argument);
+		Result visit(Division division, Argument argument);
+		Result visit(Equation equation, Argument argument);
+		Result visit(EquationsSystem equationsSystem, Argument argument);
+		Result visit(EquationsSystemPart equationsSystemPart, Argument argument);
+		Result visit(Expression expression, Argument argument);
+		Result visit(Joke joke, Argument argument);
+		Result visit(Logarithm logarithm, Argument argument);
+		Result visit(Multiplication multiplication, Argument argument);
+		Result visit(Negative negative, Argument argument);
+		Result visit(Number number, Argument argument);
+		Result visit(Power power, Argument argument);
+		Result visit(Root root, Argument argument);
+		Result visit(RootSquare rootSquare, Argument argument);
+		Result visit(Sine sine, Argument argument);
+		Result visit(Subtraction subtraction, Argument argument);
+		Result visit(SumSubtraction sumSubtraction, Argument argument);
+		Result visit(Sum sum, Argument argument);
+		Result visit(Tangent tangent, Argument argument);
+		Result visit(Undefined undefined, Argument argument);
+		Result visit(Variable variable, Argument argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/FunctionDynamic.java

@@ -133,14 +133,12 @@ public abstract class FunctionDynamic implements Function {
 
 	@Override
 	public abstract FunctionDynamic clone();
-	
+
 	@Override
 	public int hashCode() {
-		return functions.hashCode() + 883 * super.hashCode();
+		return Arrays.hashCode(functions);
 	}
 
 	@Override
-	public boolean equals(final Object o) {
-		return false;
-	}
+	public abstract boolean equals(Object o);
 }

core/src/main/java/it/cavallium/warppi/math/FunctionOperator.java

@@ -6,6 +6,8 @@ import it.cavallium.warppi.util.Errors;
 import it.cavallium.warppi.util.Utils;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
+import java.util.Objects;
+
 public abstract class FunctionOperator implements Function {
 	
 	/**
@@ -175,7 +177,7 @@ public abstract class FunctionOperator implements Function {
 
 	@Override
 	public int hashCode() {
-		return parameter1.hashCode() + 7 * parameter2.hashCode() + 883 * super.hashCode();
+		return Objects.hash(parameter1, parameter2);
 	}
 
 	@Override

core/src/main/java/it/cavallium/warppi/math/FunctionSingle.java

@@ -4,6 +4,8 @@ import it.cavallium.warppi.math.rules.Rule;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
+import java.util.Objects;
+
 public abstract class FunctionSingle implements Function {
 
 	private boolean simplified;
@@ -64,7 +66,7 @@ public abstract class FunctionSingle implements Function {
 
 	/**
 	 *
-	 * @param var
+	 * @param value
 	 *            Parameter.
 	 * @return A new instance of this function.
 	 */
@@ -117,9 +119,14 @@ public abstract class FunctionSingle implements Function {
 
 	@Override
 	public int hashCode() {
-		return parameter.hashCode() + 883 * super.hashCode();
+		return Objects.hash(parameter);
 	}
 
 	@Override
 	public abstract boolean equals(Object o);
+
+	@Override
+	public String toString() {
+		return this.getClass().getSimpleName() + "(" + getParameter() + ")";
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Division.java

@@ -59,4 +59,9 @@ public class Division extends FunctionOperator {
 		result.add(bd);
 		return result;
 	}
+
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Expression.java

@@ -582,6 +582,11 @@ public class Expression extends FunctionSingle {
 		return result;
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
+
 	@Override
 	public String toString() {
 		String s = "(";

core/src/main/java/it/cavallium/warppi/math/functions/Joke.java

@@ -61,4 +61,8 @@ public class Joke implements Function {
 		throw new Error(Errors.NOT_IMPLEMENTED, "Unknown function " + getClass().getSimpleName());
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Logarithm.java

@@ -55,4 +55,8 @@ public class Logarithm extends FunctionOperator {
 		return result;
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Multiplication.java

@@ -2,11 +2,9 @@ package it.cavallium.warppi.math.functions;
 
 import it.cavallium.warppi.gui.expression.blocks.Block;
 import it.cavallium.warppi.gui.expression.blocks.BlockChar;
+import it.cavallium.warppi.gui.expression.blocks.BlockNumericChar;
 import it.cavallium.warppi.gui.expression.blocks.BlockParenthesis;
-import it.cavallium.warppi.math.Function;
-import it.cavallium.warppi.math.FunctionOperator;
-import it.cavallium.warppi.math.MathContext;
-import it.cavallium.warppi.math.MathematicalSymbols;
+import it.cavallium.warppi.math.*;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
@@ -24,11 +22,7 @@ public class Multiplication extends FunctionOperator {
 	public boolean equals(final Object o) {
 		if (o instanceof Multiplication) {
 			final FunctionOperator f = (FunctionOperator) o;
-			if (parameter1.equals(f.getParameter1()) && parameter2.equals(f.getParameter2())) {
-				return true;
-			} else if (parameter1.equals(f.getParameter2()) && parameter2.equals(f.getParameter1())) {
-				return true;
-			}
+			return parameter1.equals(f.getParameter1()) && parameter2.equals(f.getParameter2());
 		}
 		return false;
 	}
@@ -71,7 +65,7 @@ public class Multiplication extends FunctionOperator {
 			} else {
 				result.addAll(sub1);
 			}
-			if (nearLeft instanceof BlockChar && nearRight instanceof BlockChar && !(par2 instanceof Negative) && !(par1 instanceof Number && par2 instanceof Number) && !(par1 instanceof Number && par2 instanceof Multiplication && ((Multiplication)par2).getParameter1() instanceof Number)) {
+			if (nearLeft instanceof BlockChar && nearRight instanceof BlockChar && !(nearLeft instanceof BlockNumericChar && nearRight instanceof BlockNumericChar) && !(par2 instanceof Negative) && !(par1 instanceof Number && par2 instanceof Number) && !(par1 instanceof Number && par2 instanceof Multiplication && ((Multiplication)par2).getParameter1() instanceof Number)) {
 
 			} else {
 				result.add(new BlockChar(MathematicalSymbols.MULTIPLICATION));
@@ -87,6 +81,11 @@ public class Multiplication extends FunctionOperator {
 		}
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
+
 	public boolean isNegative() {
 		return parameter1.equals(new Number(getMathContext(), -1)) || parameter2.equals(new Number(getMathContext(), -1));
 	}
@@ -104,4 +103,4 @@ public class Multiplication extends FunctionOperator {
 	public static Multiplication newNegative(final MathContext context, final Function value2) {
 		return new Multiplication(context, new Number(context, -1), value2);
 	}
-}
+}

core/src/main/java/it/cavallium/warppi/math/functions/Negative.java

@@ -3,10 +3,7 @@ package it.cavallium.warppi.math.functions;
 import it.cavallium.warppi.gui.expression.blocks.Block;
 import it.cavallium.warppi.gui.expression.blocks.BlockChar;
 import it.cavallium.warppi.gui.expression.blocks.BlockParenthesis;
-import it.cavallium.warppi.math.Function;
-import it.cavallium.warppi.math.FunctionSingle;
-import it.cavallium.warppi.math.MathContext;
-import it.cavallium.warppi.math.MathematicalSymbols;
+import it.cavallium.warppi.math.*;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
@@ -52,4 +49,9 @@ public class Negative extends FunctionSingle {
 		return blocks;
 		// throw new Error(Errors.NOT_IMPLEMENTED, "Unknown function " + getClass().getSimpleName());
 	}
+
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Number.java

@@ -4,13 +4,9 @@ import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.util.LinkedList;
 
+import it.cavallium.warppi.gui.expression.blocks.*;
 import org.nevec.rjm.BigDecimalMath;
 
-import it.cavallium.warppi.gui.expression.blocks.Block;
-import it.cavallium.warppi.gui.expression.blocks.BlockChar;
-import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
-import it.cavallium.warppi.gui.expression.blocks.BlockExponentialNotation;
-import it.cavallium.warppi.gui.expression.blocks.BlockPower;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.math.rules.Rule;
@@ -256,10 +252,10 @@ public class Number implements Function {
 			final BlockPower bp = new BlockExponentialNotation();
 			final BlockContainer bpec = bp.getExponentContainer();
 			for (final char c : numberParts[0].toCharArray()) {
-				result.add(new BlockChar(c));
+				result.add(new BlockNumericChar(c));
 			}
 			for (final char c : numberParts[1].toCharArray()) {
-				bpec.appendBlockUnsafe(new BlockChar(c));
+				bpec.appendBlockUnsafe(new BlockNumericChar(c));
 			} ;
 			bpec.recomputeDimensions();
 			bp.recomputeDimensions();
@@ -267,12 +263,17 @@ public class Number implements Function {
 			return result;
 		} else {
 			for (final char c : numberString.toCharArray()) {
-				result.add(new BlockChar(c));
+				result.add(new BlockNumericChar(c));
 			}
 		}
 		return result;
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
+
 	@Override
 	public Function setParameter(final int index, final Function var) throws IndexOutOfBoundsException {
 		throw new IndexOutOfBoundsException();

core/src/main/java/it/cavallium/warppi/math/functions/Power.java

@@ -50,4 +50,9 @@ public class Power extends FunctionOperator {
 		result.add(bp);
 		return result;
 	}
+
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/Root.java

@@ -39,4 +39,8 @@ public class Root extends FunctionOperator {
 		throw new Error(Errors.NOT_IMPLEMENTED, "Unknown function " + getClass().getSimpleName());
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
 }

core/src/main/java/it/cavallium/warppi/math/functions/RootSquare.java

@@ -5,33 +5,37 @@ import it.cavallium.warppi.gui.expression.blocks.BlockContainer;
 import it.cavallium.warppi.gui.expression.blocks.BlockSquareRoot;
 import it.cavallium.warppi.math.Function;
 import it.cavallium.warppi.math.FunctionOperator;
+import it.cavallium.warppi.math.FunctionSingle;
 import it.cavallium.warppi.math.MathContext;
 import it.cavallium.warppi.util.Error;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
-public class RootSquare extends FunctionOperator {
+public class RootSquare extends FunctionSingle {
 
-	public RootSquare(final MathContext root, final Function value2) {
-		super(root, new Number(root, 2), value2);
+	private final Number degree;
+
+	public RootSquare(final MathContext root, final Function value) {
+		super(root, value);
+		this.degree = new Number(root, 2);
 	}
 
 	@Override
 	public boolean equals(final Object o) {
-		if (o instanceof Root) {
-			final FunctionOperator f = (FunctionOperator) o;
-			return parameter1.equals(f.getParameter1()) && parameter2.equals(f.getParameter2());
+		if (o instanceof RootSquare) {
+			final RootSquare f = (RootSquare) o;
+			return parameter.equals(f.getParameter());
 		}
 		return false;
 	}
 
 	@Override
 	public RootSquare clone() {
-		return new RootSquare(mathContext, parameter2 == null ? null : parameter2.clone());
+		return new RootSquare(mathContext, parameter == null ? null : parameter.clone());
 	}
 
 	@Override
 	public RootSquare clone(MathContext c) {
-		return new RootSquare(c, parameter2 == null ? null : parameter2.clone(c));
+		return new RootSquare(c, parameter == null ? null : parameter.clone(c));
 	}
 
 	@Override
@@ -39,7 +43,7 @@ public class RootSquare extends FunctionOperator {
 		final ObjectArrayList<Block> result = new ObjectArrayList<>();
 		final BlockSquareRoot bsqr = new BlockSquareRoot();
 		final BlockContainer bsqrc = bsqr.getNumberContainer();
-		for (final Block b : getParameter2().toBlock(context)) {
+		for (final Block b : getParameter().toBlock(context)) {
 			bsqrc.appendBlockUnsafe(b);
 		}
 		bsqrc.recomputeDimensions();
@@ -48,4 +52,12 @@ public class RootSquare extends FunctionOperator {
 		return result;
 	}
 
+	@Override
+	public <Argument, Result> Result accept(final Function.Visitor<Argument, Result> visitor, final Argument argument) {
+		return visitor.visit(this, argument);
+	}
+
+	public Number getDegree() {
+		return degree;
+	}
 }