xserver-multidpi/hw/xwayland/xwayland-cursor.c
Jonas Ådahl a6e85e6330 xwayland: Add pointer warp emulator
Emulate pointer warps by locking the pointer and sending relative
motion events instead of absolute. X will keep track of the "fake"
pointer cursor position given the relative motion events, and the
client warping the cursor will warp the faked cursor position.

Various requirements need to be met for the pointer warp emulator to
enable:

The cursor must be invisible: since it would not be acceptable that a
fake cursor position would be different from the visual representation
of the cursor, emulation can only be done when there is no visual
representation done by the Wayland compositor. Thus, for the emulator
to enable, the cursor must be hidden, and would the cursor be displayed
while the emulator is active, the emulator would be destroyed.

The window that is warped within must be likely to have pointer focus.
For example, warping outside of the window region will be ignored.

The pointer warp emulator will disable itself once the fake cursor
position leaves the window region, or the cursor is made visible.

This makes various games depending on pointer warping (such as 3D
first-person shooters and stategy games using click-to-drag-map like
things) work.

Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
2016-10-05 13:51:02 -04:00

246 lines
6.8 KiB
C

/*
* Copyright © 2014 Intel Corporation
* Copyright © 2011 Kristian Høgsberg
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of the
* copyright holders not be used in advertising or publicity
* pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
#include "xwayland.h"
#include <mipointer.h>
static DevPrivateKeyRec xwl_cursor_private_key;
static void
expand_source_and_mask(CursorPtr cursor, CARD32 *data)
{
CARD32 *p, d, fg, bg;
CursorBitsPtr bits = cursor->bits;
int x, y, stride, i, bit;
p = data;
fg = ((cursor->foreRed & 0xff00) << 8) |
(cursor->foreGreen & 0xff00) | (cursor->foreGreen >> 8);
bg = ((cursor->backRed & 0xff00) << 8) |
(cursor->backGreen & 0xff00) | (cursor->backGreen >> 8);
stride = (bits->width / 8 + 3) & ~3;
for (y = 0; y < bits->height; y++)
for (x = 0; x < bits->width; x++) {
i = y * stride + x / 8;
bit = 1 << (x & 7);
if (bits->source[i] & bit)
d = fg;
else
d = bg;
if (bits->mask[i] & bit)
d |= 0xff000000;
else
d = 0x00000000;
*p++ = d;
}
}
static Bool
xwl_realize_cursor(DeviceIntPtr device, ScreenPtr screen, CursorPtr cursor)
{
PixmapPtr pixmap;
pixmap = xwl_shm_create_pixmap(screen, cursor->bits->width,
cursor->bits->height, 32, 0);
dixSetPrivate(&cursor->devPrivates, &xwl_cursor_private_key, pixmap);
return TRUE;
}
static Bool
xwl_unrealize_cursor(DeviceIntPtr device, ScreenPtr screen, CursorPtr cursor)
{
PixmapPtr pixmap;
struct xwl_screen *xwl_screen;
struct xwl_seat *xwl_seat;
pixmap = dixGetPrivate(&cursor->devPrivates, &xwl_cursor_private_key);
if (!pixmap)
return TRUE;
dixSetPrivate(&cursor->devPrivates, &xwl_cursor_private_key, NULL);
/* When called from FreeCursor(), device is always NULL */
xwl_screen = xwl_screen_get(screen);
xorg_list_for_each_entry(xwl_seat, &xwl_screen->seat_list, link) {
if (cursor == xwl_seat->x_cursor)
xwl_seat->x_cursor = NULL;
}
return xwl_shm_destroy_pixmap(pixmap);
}
static void
frame_callback(void *data,
struct wl_callback *callback,
uint32_t time)
{
struct xwl_seat *xwl_seat = data;
wl_callback_destroy (xwl_seat->cursor_frame_cb);
xwl_seat->cursor_frame_cb = NULL;
if (xwl_seat->cursor_needs_update) {
xwl_seat->cursor_needs_update = FALSE;
xwl_seat_set_cursor(xwl_seat);
}
}
static const struct wl_callback_listener frame_listener = {
frame_callback
};
void
xwl_seat_set_cursor(struct xwl_seat *xwl_seat)
{
PixmapPtr pixmap;
CursorPtr cursor;
int stride;
if (!xwl_seat->wl_pointer)
return;
if (!xwl_seat->x_cursor) {
wl_pointer_set_cursor(xwl_seat->wl_pointer,
xwl_seat->pointer_enter_serial, NULL, 0, 0);
return;
}
if (xwl_seat->cursor_frame_cb) {
xwl_seat->cursor_needs_update = TRUE;
return;
}
cursor = xwl_seat->x_cursor;
pixmap = dixGetPrivate(&cursor->devPrivates, &xwl_cursor_private_key);
if (!pixmap)
return;
stride = cursor->bits->width * 4;
if (cursor->bits->argb)
memcpy(pixmap->devPrivate.ptr,
cursor->bits->argb, cursor->bits->height * stride);
else
expand_source_and_mask(cursor, pixmap->devPrivate.ptr);
wl_pointer_set_cursor(xwl_seat->wl_pointer,
xwl_seat->pointer_enter_serial,
xwl_seat->cursor,
xwl_seat->x_cursor->bits->xhot,
xwl_seat->x_cursor->bits->yhot);
wl_surface_attach(xwl_seat->cursor,
xwl_shm_pixmap_get_wl_buffer(pixmap), 0, 0);
wl_surface_damage(xwl_seat->cursor, 0, 0,
xwl_seat->x_cursor->bits->width,
xwl_seat->x_cursor->bits->height);
xwl_seat->cursor_frame_cb = wl_surface_frame(xwl_seat->cursor);
wl_callback_add_listener(xwl_seat->cursor_frame_cb, &frame_listener, xwl_seat);
wl_surface_commit(xwl_seat->cursor);
}
static void
xwl_set_cursor(DeviceIntPtr device,
ScreenPtr screen, CursorPtr cursor, int x, int y)
{
struct xwl_seat *xwl_seat;
Bool cursor_visibility_changed;
xwl_seat = device->public.devicePrivate;
if (xwl_seat == NULL)
return;
cursor_visibility_changed = !!xwl_seat->x_cursor ^ !!cursor;
xwl_seat->x_cursor = cursor;
if (cursor_visibility_changed)
xwl_seat_cursor_visibility_changed(xwl_seat);
xwl_seat_set_cursor(xwl_seat);
}
static void
xwl_move_cursor(DeviceIntPtr device, ScreenPtr screen, int x, int y)
{
}
static Bool
xwl_device_cursor_initialize(DeviceIntPtr device, ScreenPtr screen)
{
return TRUE;
}
static void
xwl_device_cursor_cleanup(DeviceIntPtr device, ScreenPtr screen)
{
}
static miPointerSpriteFuncRec xwl_pointer_sprite_funcs = {
xwl_realize_cursor,
xwl_unrealize_cursor,
xwl_set_cursor,
xwl_move_cursor,
xwl_device_cursor_initialize,
xwl_device_cursor_cleanup
};
static Bool
xwl_cursor_off_screen(ScreenPtr *ppScreen, int *x, int *y)
{
return FALSE;
}
static void
xwl_cross_screen(ScreenPtr pScreen, Bool entering)
{
}
static void
xwl_pointer_warp_cursor(DeviceIntPtr pDev, ScreenPtr pScreen, int x, int y)
{
miPointerWarpCursor(pDev, pScreen, x, y);
}
static miPointerScreenFuncRec xwl_pointer_screen_funcs = {
xwl_cursor_off_screen,
xwl_cross_screen,
xwl_pointer_warp_cursor
};
Bool
xwl_screen_init_cursor(struct xwl_screen *xwl_screen)
{
if (!dixRegisterPrivateKey(&xwl_cursor_private_key, PRIVATE_CURSOR_BITS, 0))
return FALSE;
return miPointerInitialize(xwl_screen->screen,
&xwl_pointer_sprite_funcs,
&xwl_pointer_screen_funcs, TRUE);
}