From 144fb1593fd033458150ce84bd39061dbeac5406 Mon Sep 17 00:00:00 2001
From: Andrea Cavalli <andrea@warp.ovh>
Date: Mon, 1 May 2017 20:30:39 +0000
Subject: [PATCH] added a headless render stub

---
 .../org/warp/picalculator/gui/DisplayManager.java     | 10 ++++++++--
 .../picalculator/gui/graphicengine/gpu/GPUEngine.java | 11 +++++++++--
 .../gui/graphicengine/headless/HeadlessEngine.java    |  4 ++++
 .../gui/graphicengine/headless/HeadlessRenderer.java  |  5 +++++
 4 files changed, 26 insertions(+), 4 deletions(-)
 create mode 100755 src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessEngine.java
 create mode 100755 src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessRenderer.java

diff --git a/src/main/java/org/warp/picalculator/gui/DisplayManager.java b/src/main/java/org/warp/picalculator/gui/DisplayManager.java
index a141e1d8..1faeed82 100755
--- a/src/main/java/org/warp/picalculator/gui/DisplayManager.java
+++ b/src/main/java/org/warp/picalculator/gui/DisplayManager.java
@@ -1,8 +1,9 @@
 package org.warp.picalculator.gui;
 
 import java.io.IOException;
+
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-
+
 import org.warp.picalculator.Main;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard;
@@ -11,10 +12,11 @@ import org.warp.picalculator.gui.graphicengine.RenderingLoop;
 import org.warp.picalculator.gui.graphicengine.Renderer;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.gui.graphicengine.gpu.GPUEngine;
+import org.warp.picalculator.gui.graphicengine.headless.HeadlessEngine;
 import org.warp.picalculator.gui.graphicengine.BinaryFont;
 import org.warp.picalculator.gui.graphicengine.Skin;
 import org.warp.picalculator.gui.screens.Screen;
-
+
 import com.pi4j.wiringpi.Gpio;
 
 public final class DisplayManager implements RenderingLoop {
@@ -82,6 +84,10 @@ public final class DisplayManager implements RenderingLoop {
 			Utils.debug.println("Using CPU Graphic Engine");
 			return d;
 		}
+		d = new HeadlessEngine();
+		if (d.isSupported()) {
+			System.err.println("Using Headless Engine! This is a problem! No other graphic engines are available.");
+		}
 		throw new UnsupportedOperationException("No graphic engines available.");
 	}
 
diff --git a/src/main/java/org/warp/picalculator/gui/graphicengine/gpu/GPUEngine.java b/src/main/java/org/warp/picalculator/gui/graphicengine/gpu/GPUEngine.java
index c5a551e8..7da0b9fe 100755
--- a/src/main/java/org/warp/picalculator/gui/graphicengine/gpu/GPUEngine.java
+++ b/src/main/java/org/warp/picalculator/gui/graphicengine/gpu/GPUEngine.java
@@ -125,8 +125,15 @@ public class GPUEngine implements org.warp.picalculator.gui.graphicengine.Graphi
 
 	@Override
 	public boolean isSupported() {
-		final boolean available = GLProfile.isAvailable(GLProfile.GL2ES1);
-		if (!available) {
+		boolean available = false;
+		boolean errored = false;
+		try {
+			available = GLProfile.isAvailable(GLProfile.GL2ES1);
+        } catch (Exception ex) {
+        	errored = true;
+        	System.err.println(ex.getMessage());
+        }
+		if (!available && !errored) {
 			System.err.println(GLProfile.glAvailabilityToString());
 		}
 		return available;
diff --git a/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessEngine.java b/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessEngine.java
new file mode 100755
index 00000000..ddf7e6fd
--- /dev/null
+++ b/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessEngine.java
@@ -0,0 +1,4 @@
+package org.warp.picalculator.gui.graphicengine.headless;
+
+public class HeadlessEngine implements org.warp.picalculator.gui.graphicengine.GraphicEngine {
+}
diff --git a/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessRenderer.java b/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessRenderer.java
new file mode 100755
index 00000000..f386b974
--- /dev/null
+++ b/src/main/java/org/warp/picalculator/gui/graphicengine/headless/HeadlessRenderer.java
@@ -0,0 +1,5 @@
+package org.warp.picalculator.gui.graphicengine.headless;
+
+public class HeadlessRenderer implements Renderer {
+	
+}