[gnome-shell/wip/wayland: 159/160] ShellGlobal: don't use Gdk to query the pointer position under wayland

[Giovanni Campagna <gcampagna src gnome org>]

commit 7cab0884efc3157e9bc8cf121dde3bfe5f09f038
Author: Giovanni Campagna <gcampagn redhat com>
Date:   Wed Aug 14 16:59:39 2013 +0200

    ShellGlobal: don't use Gdk to query the pointer position under wayland
    
    Gdk uses Xwayland, so it only sees the events we forward to X11
    clients. Instead, under wayland we can use clutter and be sure
    that the value it provides reflect the actual pointer position.

 src/shell-global.c |   79 ++++++++++++++++++++++++++++++++++++----------------
 1 files changed, 55 insertions(+), 24 deletions(-)
---
diff --git a/src/shell-global.c b/src/shell-global.c
index f2ec992..2d4b282 100644
--- a/src/shell-global.c
+++ b/src/shell-global.c
@@ -1314,6 +1314,46 @@ void shell_global_init_xdnd (ShellGlobal *global)
                    32, PropModeReplace, (const unsigned char *)&global->stage_xwindow, 1);
 }
 
+void
+get_pointer_position_gdk (ShellGlobal *global,
+                          int         *x,
+                          int         *y,
+                          int         *mods)
+{
+  GdkDeviceManager *gmanager;
+  GdkDevice *gdevice;
+  GdkScreen *gscreen;
+
+  gmanager = gdk_display_get_device_manager (global->gdk_display);
+  gdevice = gdk_device_manager_get_client_pointer (gmanager);
+
+  gdk_device_get_position (gdevice, &gscreen, x, y);
+  gdk_device_get_state (gdevice,
+                        gdk_screen_get_root_window (gscreen),
+                        NULL, (GdkModifierType*)mods);
+}
+
+#ifdef HAVE_WAYLAND
+void
+get_pointer_position_clutter (ShellGlobal *global,
+                              int         *x,
+                              int         *y,
+                              int         *mods)
+{
+  ClutterDeviceManager *cmanager;
+  ClutterInputDevice *cdevice;
+  ClutterPoint point;
+
+  cmanager = clutter_device_manager_get_default ();
+  cdevice = clutter_device_manager_get_core_device (cmanager, CLUTTER_POINTER_DEVICE);
+
+  clutter_input_device_get_coords (cdevice, NULL, &point);
+  *x = point.x;
+  *y = point.y;
+  *mods = clutter_input_device_get_modifier_state (cdevice);
+}
+#endif
+
 /**
  * shell_global_get_pointer:
  * @global: the #ShellGlobal
@@ -1322,9 +1362,6 @@ void shell_global_init_xdnd (ShellGlobal *global)
  * @mods: (out): the current set of modifier keys that are pressed down
  *
  * Gets the pointer coordinates and current modifier key state.
- * This is a wrapper around gdk_display_get_pointer() that strips
- * out any un-declared modifier flags, to make gjs happy; see
- * https://bugzilla.gnome.org/show_bug.cgi?id=597292.
  */
 void
 shell_global_get_pointer (ShellGlobal         *global,
@@ -1332,17 +1369,20 @@ shell_global_get_pointer (ShellGlobal         *global,
                           int                 *y,
                           ClutterModifierType *mods)
 {
-  GdkDeviceManager *gmanager;
-  GdkDevice *gdevice;
-  GdkScreen *gscreen;
-  GdkModifierType raw_mods;
+  int raw_mods;
+
+  /* We can't use the clutter interface when not running as a wayland compositor,
+     because we need to query the server, rather than using the last cached value.
+     OTOH, on wayland we can't use GDK, because that only sees the events
+     we forward to xwayland.
+  */
+#ifdef HAVE_WAYLAND
+  if (meta_is_wayland_compositor ())
+    get_pointer_position_clutter (global, x, y, &raw_mods);
+  else
+#endif
+    get_pointer_position_gdk (global, x, y, &raw_mods);
 
-  gmanager = gdk_display_get_device_manager (global->gdk_display);
-  gdevice = gdk_device_manager_get_client_pointer (gmanager);
-  gdk_device_get_position (gdevice, &gscreen, x, y);
-  gdk_device_get_state (gdevice,
-                        gdk_screen_get_root_window (gscreen),
-                        NULL, &raw_mods);
   *mods = raw_mods & GDK_MODIFIER_MASK;
 }
 
@@ -1358,19 +1398,10 @@ void
 shell_global_sync_pointer (ShellGlobal *global)
 {
   int x, y;
-  GdkModifierType mods;
-  GdkDeviceManager *gmanager;
-  GdkDevice *gdevice;
-  GdkScreen *gscreen;
+  ClutterModifierType mods;
   ClutterMotionEvent event;
 
-  gmanager = gdk_display_get_device_manager (global->gdk_display);
-  gdevice = gdk_device_manager_get_client_pointer (gmanager);
-
-  gdk_device_get_position (gdevice, &gscreen, &x, &y);
-  gdk_device_get_state (gdevice,
-                        gdk_screen_get_root_window (gscreen),
-                        NULL, &mods);
+  shell_global_get_pointer (global, &x, &y, &mods);
 
   event.type = CLUTTER_MOTION;
   event.time = shell_global_get_current_time (global);