x11: Store a back pointer to the backend in the stage

Since we access it in order to get the X11 Display pointer, it makes
sense to have the ClutterBackendX11 already available inside the
ClutterStageX11 structure, and avoid the pattern:

  ClutterBackend *backend = clutter_get_default_backend ();
  ClutterBackendX11 *backend_x11 = CLUTTER_BACKEND_X11 (backend);

which costs us a function call, a type cast and an unused variable.

clutter/egl/clutter-backend-egl.c

@@ -767,6 +767,7 @@ clutter_backend_egl_create_stage (ClutterBackend  *backend,
   /* copy backend data into the stage */
   stage_x11 = CLUTTER_STAGE_X11 (stage);
   stage_x11->wrapper = wrapper;
+  stage_x11->backend = backend_x11;
 
   translator = CLUTTER_EVENT_TRANSLATOR (stage_x11);
   _clutter_backend_x11_add_event_translator (backend_x11, translator);

clutter/glx/clutter-backend-glx.c

@@ -809,6 +809,7 @@ clutter_backend_glx_create_stage (ClutterBackend  *backend,
   /* copy backend data into the stage */
   stage_x11 = CLUTTER_STAGE_X11 (stage_window);
   stage_x11->wrapper = wrapper;
+  stage_x11->backend = backend_x11;
 
   translator = CLUTTER_EVENT_TRANSLATOR (stage_x11);
   _clutter_backend_x11_add_event_translator (backend_x11, translator);

clutter/x11/clutter-stage-x11.c

@@ -92,9 +92,9 @@ send_wmspec_change_state (ClutterBackendX11 *backend_x11,
   xclient.data.l[4] = 0;
 
   XSendEvent (backend_x11->xdpy, 
-              DefaultRootWindow(backend_x11->xdpy), 
+              DefaultRootWindow (backend_x11->xdpy),
               False,
-              SubstructureRedirectMask|SubstructureNotifyMask,
+              SubstructureRedirectMask | SubstructureNotifyMask,
               (XEvent *)&xclient);
 }
 
@@ -127,19 +127,15 @@ clutter_stage_x11_fix_window_size (ClutterStageX11 *stage_x11,
                                    gint             new_width,
                                    gint             new_height)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
-  gboolean resize;
-
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
-  resize = clutter_stage_get_user_resizable (stage_x11->wrapper);
 
   if (stage_x11->xwin != None && !stage_x11->is_foreign_xwin)
     {
       guint min_width, min_height;
       XSizeHints *size_hints;
+      gboolean resize;
+
+      resize = clutter_stage_get_user_resizable (stage_x11->wrapper);
 
       size_hints = XAllocSizeHints();
 
@@ -184,14 +180,10 @@ clutter_stage_x11_fix_window_size (ClutterStageX11 *stage_x11,
 static void
 clutter_stage_x11_set_wm_protocols (ClutterStageX11 *stage_x11)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
   Atom protocols[2];
   int n = 0;
   
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
   protocols[n++] = backend_x11->atom_WM_DELETE_WINDOW;
   protocols[n++] = backend_x11->atom_NET_WM_PING;
 
@@ -202,12 +194,8 @@ static void
 clutter_stage_x11_get_geometry (ClutterStageWindow *stage_window,
                                 ClutterGeometry    *geometry)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
-  ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
-
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   /* If we're fullscreen, return the size of the display. */
   if ((stage_x11->state & CLUTTER_STAGE_STATE_FULLSCREEN) &&
@@ -228,9 +216,8 @@ clutter_stage_x11_resize (ClutterStageWindow *stage_window,
                           gint                width,
                           gint                height)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
-  ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
   gboolean resize;
 
   if (stage_x11->is_foreign_xwin)
@@ -251,9 +238,6 @@ clutter_stage_x11_resize (ClutterStageWindow *stage_window,
 
   resize = clutter_stage_get_user_resizable (stage_x11->wrapper);
 
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
   if (width == 0 || height == 0)
     {
       /* Should not happen, if this turns up we need to debug it and
@@ -297,8 +281,7 @@ clutter_stage_x11_resize (ClutterStageWindow *stage_window,
 static inline void
 set_wm_pid (ClutterStageX11 *stage_x11)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11 = CLUTTER_BACKEND_X11 (backend);
   long pid;
 
   if (stage_x11->xwin == None || stage_x11->is_foreign_xwin)
@@ -322,11 +305,7 @@ set_wm_pid (ClutterStageX11 *stage_x11)
 static inline void
 set_wm_title (ClutterStageX11 *stage_x11)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
-
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   if (stage_x11->xwin == None || stage_x11->is_foreign_xwin)
     return;
@@ -353,11 +332,7 @@ set_wm_title (ClutterStageX11 *stage_x11)
 static inline void
 set_cursor_visible (ClutterStageX11 *stage_x11)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
-
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   if (stage_x11->xwin == None)
     return;
@@ -401,15 +376,14 @@ static gboolean
 clutter_stage_x11_realize (ClutterStageWindow *stage_window)
 {
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
   ClutterDeviceManager *device_manager;
-  ClutterBackendX11 *backend_x11;
   int event_flags;
 
   set_wm_pid (stage_x11);
   set_wm_title (stage_x11);
   set_cursor_visible (stage_x11);
 
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
 
   /* the masks for the events we want to select on a stage window;
    * KeyPressMask and KeyReleaseMask are necessary even with XI1
@@ -471,18 +445,18 @@ static void
 clutter_stage_x11_set_fullscreen (ClutterStageWindow *stage_window,
                                   gboolean            is_fullscreen)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
-  ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
   ClutterStage *stage = stage_x11->wrapper;
+  gboolean was_fullscreen;
 
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
+  if (stage == NULL || CLUTTER_ACTOR_IN_DESTRUCTION (stage))
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
-  if (stage == NULL)
     return;
 
-  if (!!(stage_x11->state & CLUTTER_STAGE_STATE_FULLSCREEN) == is_fullscreen)
+  was_fullscreen = ((stage_x11->state & CLUTTER_STAGE_STATE_FULLSCREEN) != 0);
+  is_fullscreen = !!is_fullscreen;
+
+  if (was_fullscreen == is_fullscreen)
     return;
 
   CLUTTER_NOTE (BACKEND, "%ssetting fullscreen", is_fullscreen ? "" : "un");
@@ -606,8 +580,7 @@ clutter_stage_x11_set_user_resizable (ClutterStageWindow *stage_window,
 static inline void
 update_wm_hints (ClutterStageX11 *stage_x11)
 {
-  ClutterBackend *backend;
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
   XWMHints wm_hints;
 
   if (stage_x11->wm_state & STAGE_X11_WITHDRAWN)
@@ -616,10 +589,6 @@ update_wm_hints (ClutterStageX11 *stage_x11)
   if (stage_x11->is_foreign_xwin)
     return;
 
-  backend = clutter_get_default_backend ();
-  g_assert (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
   wm_hints.flags = StateHint | InputHint;
   wm_hints.initial_state = NormalState;
   wm_hints.input = stage_x11->accept_focus ? True : False;
@@ -660,12 +629,8 @@ static void
 clutter_stage_x11_show (ClutterStageWindow *stage_window,
                         gboolean            do_raise)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
-  ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
-
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   if (stage_x11->xwin != None)
     {
@@ -703,12 +668,8 @@ clutter_stage_x11_show (ClutterStageWindow *stage_window,
 static void
 clutter_stage_x11_hide (ClutterStageWindow *stage_window)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
-  ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (stage_window);
-
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  g_return_if_fail (CLUTTER_IS_BACKEND_X11 (backend));
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   if (stage_x11->xwin != None)
     {
@@ -744,9 +705,8 @@ static void
 clutter_stage_x11_dispose (GObject *gobject)
 {
   ClutterEventTranslator *translator = CLUTTER_EVENT_TRANSLATOR (gobject);
-  ClutterBackendX11 *backend_x11;
+  ClutterBackendX11 *backend_x11 = CLUTTER_STAGE_X11 (gobject)->backend;
 
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
   _clutter_backend_x11_remove_event_translator (backend_x11, translator);
 
   G_OBJECT_CLASS (clutter_stage_x11_parent_class)->dispose (gobject);
@@ -870,17 +830,15 @@ clutter_stage_x11_translate_event (ClutterEventTranslator *translator,
 {
   ClutterStageX11 *stage_x11 = CLUTTER_STAGE_X11 (translator);
   ClutterTranslateReturn res = CLUTTER_TRANSLATE_CONTINUE;
-  XEvent *xevent = native;
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
-  ClutterBackendX11 *backend_x11;
-  ClutterStage *stage;
   Window stage_xwindow = stage_x11->xwin;
+  XEvent *xevent = native;
+  ClutterStage *stage;
 
   stage = clutter_x11_get_stage_from_window (xevent->xany.window);
   if (stage == NULL)
     return CLUTTER_TRANSLATE_CONTINUE;
 
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
-
   switch (xevent->type)
     {
     case ConfigureNotify:
@@ -1239,8 +1197,7 @@ set_foreign_window_callback (ClutterActor *actor,
                              void         *data)
 {
   ForeignWindowData *fwd = data;
-  ClutterBackend *backend = clutter_get_default_backend ();
+  ClutterBackendX11 *backend_x11 = fwd->stage_x11->backend;
-  ClutterBackendX11 *backend_x11 = CLUTTER_BACKEND_X11 (backend);
 
   CLUTTER_NOTE (BACKEND, "Setting foreign window (0x%x)",
                 (unsigned int) fwd->xwindow);
@@ -1282,7 +1239,6 @@ gboolean
 clutter_x11_set_stage_foreign (ClutterStage *stage,
                                Window        xwindow)
 {
-  ClutterBackend *backend = clutter_get_default_backend ();
   ClutterBackendX11 *backend_x11;
   ClutterStageX11 *stage_x11;
   ClutterStageWindow *impl;
@@ -1294,14 +1250,13 @@ clutter_x11_set_stage_foreign (ClutterStage *stage,
   ForeignWindowData fwd;
   XVisualInfo *xvisinfo;
 
-  g_return_val_if_fail (CLUTTER_IS_BACKEND_X11 (backend), FALSE);
-  backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
   g_return_val_if_fail (CLUTTER_IS_STAGE (stage), FALSE);
   g_return_val_if_fail (!CLUTTER_ACTOR_IN_DESTRUCTION (stage), FALSE);
   g_return_val_if_fail (xwindow != None, FALSE);
 
-  actor = CLUTTER_ACTOR (stage);
+  impl = _clutter_stage_get_window (stage);
+  stage_x11 = CLUTTER_STAGE_X11 (impl);
+  backend_x11 = stage_x11->backend;
 
   xvisinfo = _clutter_backend_x11_get_visual_info (backend_x11);
   g_return_val_if_fail (xvisinfo != NULL, FALSE);
@@ -1338,9 +1293,6 @@ clutter_x11_set_stage_foreign (ClutterStage *stage,
       return FALSE;
     }
 
-  impl = _clutter_stage_get_window (stage);
-  stage_x11 = CLUTTER_STAGE_X11 (impl);
-
   fwd.stage_x11 = stage_x11;
   fwd.xwindow = xwindow;
 
@@ -1355,6 +1307,8 @@ clutter_x11_set_stage_foreign (ClutterStage *stage,
   fwd.geom.width = width;
   fwd.geom.height = height;
 
+  actor = CLUTTER_ACTOR (stage);
+
   _clutter_actor_rerealize (actor,
                             set_foreign_window_callback,
                             &fwd);
@@ -1368,7 +1322,7 @@ clutter_x11_set_stage_foreign (ClutterStage *stage,
    * in the Cogl viewport changing when _clutter_do_redraw
    * calls _clutter_stage_maybe_setup_viewport().
    */
-  clutter_actor_queue_relayout (CLUTTER_ACTOR (stage));
+  clutter_actor_queue_relayout (actor);
 
   return TRUE;
 }
@@ -1378,9 +1332,7 @@ _clutter_stage_x11_destroy_window_untrapped (ClutterStageX11 *stage_x11)
 {
   if (!stage_x11->is_foreign_xwin && stage_x11->xwin != None)
     {
-      ClutterBackendX11 *backend_x11;
+      ClutterBackendX11 *backend_x11 = stage_x11->backend;
-
-      backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
 
       XDestroyWindow (backend_x11->xdpy, stage_x11->xwin);
       stage_x11->xwin = None;
@@ -1405,7 +1357,7 @@ _clutter_stage_x11_destroy_window (ClutterStageX11 *stage_x11)
 gboolean
 _clutter_stage_x11_create_window (ClutterStageX11 *stage_x11)
 {
-  ClutterBackendX11 *backend_x11;
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
   XSetWindowAttributes xattr;
   XVisualInfo *xvisinfo;
   unsigned long mask;
@@ -1416,8 +1368,6 @@ _clutter_stage_x11_create_window (ClutterStageX11 *stage_x11)
 
   CLUTTER_NOTE (MISC, "Creating stage X window");
 
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
-
   xvisinfo = _clutter_backend_x11_get_visual_info (backend_x11);
   if (xvisinfo == NULL)
     {
@@ -1473,10 +1423,7 @@ void
 _clutter_stage_x11_set_user_time (ClutterStageX11 *stage_x11,
                                   guint32          user_time)
 {
-  ClutterBackendX11 *backend_x11;
+  set_user_time (stage_x11->backend, stage_x11, user_time);
-
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
-  set_user_time (backend_x11, stage_x11, user_time);
 }
 
 gboolean
@@ -1484,13 +1431,11 @@ _clutter_stage_x11_get_root_coords (ClutterStageX11 *stage_x11,
                                     gint            *root_x,
                                     gint            *root_y)
 {
-  ClutterBackendX11 *backend_x11;
+  ClutterBackendX11 *backend_x11 = stage_x11->backend;
   gint return_val;
   Window child;
   gint tx, ty;
 
-  backend_x11 = CLUTTER_BACKEND_X11 (clutter_get_default_backend ());
-
   return_val = XTranslateCoordinates (backend_x11->xdpy,
                                       stage_x11->xwin,
                                       backend_x11->xwin_root,

clutter/x11/clutter-stage-x11.h

@@ -67,10 +67,9 @@ struct _ClutterStageX11
 
   ClutterStageX11State wm_state;
 
-  int event_types[CLUTTER_X11_XINPUT_LAST_EVENT];
+  /* backpointers */
-  GList *devices;
-
   ClutterStage *wrapper;
+  ClutterBackendX11 *backend;
 };
 
 struct _ClutterStageX11Class