cogl-renderer: Move the XEvent filters to be generic for all renderers

Instead of having cogl_renderer_xlib_add_filter and friends there is
now cogl_renderer_add_native_filter which can be used regardless of
the backend. The callback function for the filter now just takes a
void pointer instead of an XEvent pointer which should be interpreted
differently depending on the backend. For example, on Xlib it would
still be an XEvent but on Windows it could be a MSG. This simplifies
the code somewhat because the _cogl_xlib_add_filter no longer needs to
have its own filter list when a stub renderer is used because there is
always a renderer available.

cogl_renderer_xlib_handle_event has also been renamed to
cogl_renderer_handle_native_event. This just forwards the event on to
all of the listeners. The backend renderer is expected to register its
own event filter if it wants to process the events in some way.

clutter/cogl/cogl/cogl-renderer-private.h

@@ -37,6 +37,8 @@ struct _CoglRenderer
 #ifdef COGL_HAS_XLIB_SUPPORT
   Display *foreign_xdpy;
 #endif
+  /* List of callback functions that will be given every native event */
+  GSList *event_filters;
   void *winsys;
 };
 

clutter/cogl/cogl/cogl-renderer-xlib-private.h

@@ -34,8 +34,6 @@ typedef struct _CoglRendererXlib
 
   Display *xdpy;
 
-  /* List of callback functions that will be given every Xlib event */
-  GSList *event_filters;
   /* Current top of the XError trap state stack. The actual memory for
      these is expected to be allocated on the stack by the caller */
   CoglXlibTrapState *trap_state;

clutter/cogl/cogl/cogl-renderer-xlib.c

@@ -43,82 +43,6 @@
 static char *_cogl_x11_display_name = NULL;
 static GList *_cogl_xlib_renderers = NULL;
 
-CoglXlibFilterReturn
-cogl_renderer_xlib_handle_event (CoglRenderer *renderer,
-                                 XEvent *xevent)
-{
-  CoglRendererXlib *xlib_renderer = renderer->winsys;
-  GSList *l;
-
-  g_return_val_if_fail (xlib_renderer->xdpy != NULL, COGL_XLIB_FILTER_CONTINUE);
-
-  /* XXX: should this be a more graceful check? */
-  g_return_val_if_fail (xlib_renderer != NULL, COGL_XLIB_FILTER_CONTINUE);
-
-  /* Pass the event on to all of the registered filters in turn */
-  for (l = xlib_renderer->event_filters; l; l = l->next)
-    {
-      CoglXlibFilterClosure *closure = l->data;
-
-      if (closure->func (xevent, closure->data) == COGL_XLIB_FILTER_REMOVE)
-        return COGL_XLIB_FILTER_REMOVE;
-    }
-
-  switch (xevent->type)
-    {
-      /* TODO... */
-    default:
-      break;
-    }
-
-  return COGL_XLIB_FILTER_CONTINUE;
-}
-
-void
-cogl_renderer_xlib_add_filter (CoglRenderer *renderer,
-                               CoglXlibFilterFunc func,
-                               void *data)
-{
-  CoglRendererXlib *xlib_renderer;
-  CoglXlibFilterClosure *closure;
-
-  xlib_renderer = renderer->winsys;
-
-  closure = g_slice_new (CoglXlibFilterClosure);
-  closure->func = func;
-  closure->data = data;
-
-  xlib_renderer->event_filters =
-    g_slist_prepend (xlib_renderer->event_filters, closure);
-}
-
-void
-cogl_renderer_xlib_remove_filter (CoglRenderer *renderer,
-                                  CoglXlibFilterFunc func,
-                                  void *data)
-{
-  CoglRendererXlib *xlib_renderer;
-  GSList *l, *prev = NULL;
-
-  xlib_renderer = renderer->winsys;
-
-  for (l = xlib_renderer->event_filters; l; prev = l, l = l->next)
-    {
-      CoglXlibFilterClosure *closure = l->data;
-
-      if (closure->func == func && closure->data == data)
-        {
-          g_slice_free (CoglXlibFilterClosure, closure);
-          if (prev)
-            prev->next = g_slist_delete_link (prev->next, l);
-          else
-            xlib_renderer->event_filters =
-              g_slist_delete_link (xlib_renderer->event_filters, l);
-          break;
-        }
-    }
-}
-
 static void
 register_xlib_renderer (CoglRenderer *renderer)
 {
@@ -245,8 +169,6 @@ _cogl_renderer_xlib_connect (CoglRenderer *renderer, GError **error)
                               &damage_error))
     x11_renderer->damage_base = -1;
 
-  xlib_renderer->event_filters = NULL;
-
   xlib_renderer->trap_state = NULL;
 
   register_xlib_renderer (renderer);
@@ -254,21 +176,11 @@ _cogl_renderer_xlib_connect (CoglRenderer *renderer, GError **error)
   return TRUE;
 }
 
-static void
-free_xlib_filter_closure (void *data, void *user_data)
-{
-  g_slice_free (CoglXlibFilterClosure, data);
-}
-
 void
 _cogl_renderer_xlib_disconnect (CoglRenderer *renderer)
 {
   CoglRendererXlib *xlib_renderer = renderer->winsys;
 
-  g_slist_foreach (xlib_renderer->event_filters,
-                   free_xlib_filter_closure, NULL);
-  g_slist_free (xlib_renderer->event_filters);
-
   if (!renderer->foreign_xdpy)
     XCloseDisplay (xlib_renderer->xdpy);
 

clutter/cogl/cogl/cogl-renderer.c

@@ -41,18 +41,36 @@ static void _cogl_renderer_free (CoglRenderer *renderer);
 
 COGL_OBJECT_DEFINE (Renderer, renderer);
 
+typedef struct _CoglNativeFilterClosure
+{
+  CoglNativeFilterFunc func;
+  void *data;
+} CoglNativeFilterClosure;
+
 GQuark
 cogl_renderer_error_quark (void)
 {
   return g_quark_from_static_string ("cogl-renderer-error-quark");
 }
 
+static void
+native_filter_closure_free (CoglNativeFilterClosure *closure)
+{
+  g_slice_free (CoglNativeFilterClosure, closure);
+}
+
 static void
 _cogl_renderer_free (CoglRenderer *renderer)
 {
 #ifdef COGL_HAS_FULL_WINSYS
   _cogl_winsys_renderer_disconnect (renderer);
 #endif
+
+  g_slist_foreach (renderer->event_filters,
+                   (GFunc) native_filter_closure_free,
+                   NULL);
+  g_slist_free (renderer->event_filters);
+
   g_free (renderer);
 }
 
@@ -62,6 +80,7 @@ cogl_renderer_new (void)
   CoglRenderer *renderer = g_new0 (CoglRenderer, 1);
 
   renderer->connected = FALSE;
+  renderer->event_filters = NULL;
 
   return _cogl_renderer_object_new (renderer);
 }
@@ -127,3 +146,66 @@ cogl_renderer_connect (CoglRenderer *renderer, GError **error)
   renderer->connected = TRUE;
   return TRUE;
 }
+
+CoglFilterReturn
+cogl_renderer_handle_native_event (CoglRenderer *renderer,
+                                   void *event)
+{
+  GSList *l, *next;
+
+  /* Pass the event on to all of the registered filters in turn */
+  for (l = renderer->event_filters; l; l = next)
+    {
+      CoglNativeFilterClosure *closure = l->data;
+
+      /* The next pointer is taken now so that we can handle the
+         closure being removed during emission */
+      next = l->next;
+
+      if (closure->func (event, closure->data) == COGL_FILTER_REMOVE)
+        return COGL_FILTER_REMOVE;
+    }
+
+  /* If the backend for the renderer also wants to see the events, it
+     should just register its own filter */
+
+  return COGL_FILTER_CONTINUE;
+}
+
+void
+cogl_renderer_add_native_filter (CoglRenderer *renderer,
+                                 CoglNativeFilterFunc func,
+                                 void *data)
+{
+  CoglNativeFilterClosure *closure;
+
+  closure = g_slice_new (CoglNativeFilterClosure);
+  closure->func = func;
+  closure->data = data;
+
+  renderer->event_filters = g_slist_prepend (renderer->event_filters, closure);
+}
+
+void
+cogl_renderer_remove_native_filter (CoglRenderer *renderer,
+                                    CoglNativeFilterFunc func,
+                                    void *data)
+{
+  GSList *l, *prev = NULL;
+
+  for (l = renderer->event_filters; l; prev = l, l = l->next)
+    {
+      CoglNativeFilterClosure *closure = l->data;
+
+      if (closure->func == func && closure->data == data)
+        {
+          native_filter_closure_free (closure);
+          if (prev)
+            prev->next = g_slist_delete_link (prev->next, l);
+          else
+            renderer->event_filters =
+              g_slist_delete_link (renderer->event_filters, l);
+          break;
+        }
+    }
+}

clutter/cogl/cogl/cogl-renderer.h

@@ -63,27 +63,57 @@ cogl_renderer_new (void);
 
 /* optional configuration APIs */
 
-#ifdef COGL_HAS_XLIB
+#define cogl_renderer_handle_native_event cogl_renderer_handle_native_event_EXP
-
-#define cogl_renderer_xlib_handle_event cogl_renderer_xlib_handle_event_EXP
 /*
- * cogl_renderer_xlib_handle_event:
+ * cogl_renderer_handle_native_event:
- * @xevent: pointer to XEvent structure
+ * @event: pointer to native event structure
  *
- * This function processes a single X event; it can be used to hook
+ * This function processes a single event; it can be used to hook into
- * into external X event retrieval (for example that done by Clutter
+ * external event retrieval (for example that done by Clutter or
- * or GDK).
+ * GDK). The type of the structure that event points to depends on the
+ * window system used for the renderer. On an xlib renderer it would
+ * be a pointer to an XEvent or an a Windows renderer it would be a
+ * pointer to a MSG struct.
  *
- * Return value: #CoglXlibFilterReturn. %COGL_XLIB_FILTER_REMOVE
+ * Return value: #CoglFilterReturn. %COGL_FILTER_REMOVE indicates that
- * indicates that Cogl has internally handled the event and the
+ * Cogl has internally handled the event and the caller should do no
- * caller should do no further processing. %COGL_XLIB_FILTER_CONTINUE
+ * further processing. %COGL_FILTER_CONTINUE indicates that Cogl is
- * indicates that Cogl is either not interested in the event,
+ * either not interested in the event, or has used the event to update
- * or has used the event to update internal state without taking
+ * internal state without taking any exclusive action.
- * any exclusive action.
  */
-CoglXlibFilterReturn
+CoglFilterReturn
-cogl_renderer_xlib_handle_event (CoglRenderer *renderer,
+cogl_renderer_handle_native_event (CoglRenderer *renderer,
-                                 XEvent *xevent);
+                                   void *event);
+
+#define cogl_renderer_add_native_filter cogl_renderer_add_native_filter_EXP
+/*
+ * _cogl_renderer_add_native_filter:
+ *
+ * Adds a callback function that will receive all native events. The
+ * function can stop further processing of the event by return
+ * %COGL_FILTER_REMOVE. What is considered a native event depends on
+ * the type of renderer used. An xlib based renderer would pass all
+ * XEvents whereas a Windows based renderer would pass MSGs.
+ */
+void
+cogl_renderer_add_native_filter (CoglRenderer *renderer,
+                                 CoglNativeFilterFunc func,
+                                 void *data);
+
+#define cogl_renderer_remove_native_filter \
+  cogl_renderer_remove_native_filter_EXP
+/*
+ * _cogl_renderer_remove_native_filter:
+ *
+ * Removes a callback that was previously added with
+ * _cogl_renderer_add_native_filter().
+ */
+void
+cogl_renderer_remove_native_filter (CoglRenderer *renderer,
+                                    CoglNativeFilterFunc func,
+                                    void *data);
+
+#ifdef COGL_HAS_XLIB
 
 #define cogl_renderer_xlib_get_foreign_display \
   cogl_renderer_xlib_get_foreign_display_EXP
@@ -113,30 +143,6 @@ cogl_renderer_xlib_set_foreign_display (CoglRenderer *renderer,
 Display *
 cogl_renderer_xlib_get_display (CoglRenderer *renderer);
 
-#define cogl_renderer_xlib_add_filter cogl_renderer_xlib_add_filter_EXP
-/*
- * _cogl_xlib_add_filter:
- *
- * Adds a callback function that will receive all X11 events. The
- * function can stop further processing of the event by return
- * %COGL_XLIB_FILTER_REMOVE.
- */
-void
-cogl_renderer_xlib_add_filter (CoglRenderer *renderer,
-                               CoglXlibFilterFunc func,
-                               void *data);
-
-#define cogl_renderer_xlib_remove_filter cogl_renderer_xlib_remove_filter_EXP
-/*
- * _cogl_xlib_remove_filter:
- *
- * Removes a callback that was previously added with
- * _cogl_xlib_add_filter().
- */
-void
-cogl_renderer_xlib_remove_filter (CoglRenderer *renderer,
-                                  CoglXlibFilterFunc func,
-                                  void *data);
 #endif /* COGL_HAS_XLIB */
 
 #define cogl_renderer_check_onscreen_template \

clutter/cogl/cogl/cogl-types.h

@@ -596,19 +596,19 @@ typedef enum { /*< prefix=COGL_RENDERER_ERROR >*/
 } CoglRendererError;
 
 /*
- * CoglXlibFilterReturn:
+ * CoglFilterReturn:
- * @COGL_XLIB_FILTER_CONTINUE: The event was not handled, continues the
+ * @COGL_FILTER_CONTINUE: The event was not handled, continues the
  *                        processing
- * @COGL_XLIB_FILTER_REMOVE: Remove the event, stops the processing
+ * @COGL_FILTER_REMOVE: Remove the event, stops the processing
  *
- * Return values for the #CoglXlibFilterFunc function.
+ * Return values for the #CoglFilterFunc function.
  *
  * Stability: Unstable
  */
-typedef enum _CoglXlibFilterReturn { /*< prefix=COGL_XLIB_FILTER >*/
+typedef enum _CoglFilterReturn { /*< prefix=COGL_FILTER >*/
-  COGL_XLIB_FILTER_CONTINUE,
+  COGL_FILTER_CONTINUE,
-  COGL_XLIB_FILTER_REMOVE
+  COGL_FILTER_REMOVE
-} CoglXlibFilterReturn;
+} CoglFilterReturn;
 
 typedef enum _CoglWinsysFeature
 {
@@ -651,20 +651,23 @@ typedef enum _CoglWinsysFeature
  * so although they aren't explicitly guarded they are implicitly
  * experimental too. */
 
-#ifdef COGL_HAS_XLIB
-
 /*
- * CoglXlibFilterFunc:
+ * CoglNativeFilterFunc:
+ * @native_event: A pointer to the native system event
+ * @data: The data that was given when the filter was added
  *
  * A callback function that can be registered with
- * _cogl_xlib_add_filter. The function should return
+ * cogl_renderer_add_native_filter(). The function should return
- * %COGL_XLIB_FILTER_REMOVE if it wants to prevent further processing
+ * %COGL_FILTER_REMOVE if it wants to prevent further processing or
- * or %COGL_XLIB_FILTER_CONTINUE otherwise.
+ * %COGL_FILTER_CONTINUE otherwise.
+ *
+ * The type that @native_event points to depends on the type of the
+ * underlying renderer. On xlib based renderers this would point to an
+ * XEvent struct and on Windows it would point to a MSG struct.
  */
-typedef CoglXlibFilterReturn (* CoglXlibFilterFunc) (XEvent *xevent,
+typedef CoglFilterReturn (* CoglNativeFilterFunc) (void *native_event,
                                                    void *data);
 
-#endif /* COGL_HAS_XLIB */
 
 G_END_DECLS
 

clutter/cogl/cogl/cogl-xlib-private.h

@@ -40,12 +40,6 @@ struct _CoglXlibTrapState
   CoglXlibTrapState *old_state;
 };
 
-typedef struct _CoglXlibFilterClosure
-{
-  CoglXlibFilterFunc func;
-  void *data;
-} CoglXlibFilterClosure;
-
 void
 _cogl_xlib_query_damage_extension (void);
 
@@ -66,7 +60,7 @@ _cogl_xlib_untrap_errors (CoglXlibTrapState *state);
  * %COGL_XLIB_FILTER_REMOVE.
  */
 void
-_cogl_xlib_add_filter (CoglXlibFilterFunc func,
+_cogl_xlib_add_filter (CoglNativeFilterFunc func,
                        void *data);
 
 /*
@@ -76,7 +70,7 @@ _cogl_xlib_add_filter (CoglXlibFilterFunc func,
  * _cogl_xlib_add_filter().
  */
 void
-_cogl_xlib_remove_filter (CoglXlibFilterFunc func,
+_cogl_xlib_remove_filter (CoglNativeFilterFunc func,
                           void *data);
 
 #endif /* __COGL_XLIB_PRIVATE_H */

clutter/cogl/cogl/cogl-xlib.c

@@ -52,35 +52,6 @@
    context is created */
 static Display *_cogl_xlib_display = NULL;
 
-CoglXlibFilterReturn
-cogl_xlib_handle_event (XEvent *xevent)
-{
-  GSList *l;
-
-  _COGL_GET_CONTEXT (ctx, COGL_XLIB_FILTER_CONTINUE);
-
-  if (!ctx->stub_winsys)
-    return cogl_renderer_xlib_handle_event (ctx->display->renderer, xevent);
-
-  /* Pass the event on to all of the registered filters in turn */
-  for (l = ctx->event_filters; l; l = l->next)
-    {
-      CoglXlibFilterClosure *closure = l->data;
-
-      if (closure->func (xevent, closure->data) == COGL_XLIB_FILTER_REMOVE)
-        return COGL_XLIB_FILTER_REMOVE;
-    }
-
-  switch (xevent->type)
-    {
-      /* TODO... */
-    default:
-      break;
-    }
-
-  return COGL_XLIB_FILTER_CONTINUE;
-}
-
 Display *
 cogl_xlib_get_display (void)
 {
@@ -104,59 +75,34 @@ cogl_xlib_set_display (Display *display)
   _cogl_xlib_display = display;
 }
 
-void
+/* These three functions are wrappers around the equivalent renderer
-_cogl_xlib_add_filter (CoglXlibFilterFunc func,
+   functions. They can be removed once all xlib-based backends in
-                       void *data)
+   Clutter know about the renderer */
+CoglFilterReturn
+cogl_xlib_handle_event (XEvent *xevent)
 {
-  CoglXlibFilterClosure *closure;
+  _COGL_GET_CONTEXT (ctx, COGL_FILTER_CONTINUE);
 
-  _COGL_GET_CONTEXT (ctx, NO_RETVAL);
+  /* Pass the event on to the renderer */
-
+  return cogl_renderer_handle_native_event (ctx->display->renderer, xevent);
-  if (!ctx->stub_winsys)
-    {
-      cogl_renderer_xlib_add_filter (ctx->display->renderer,
-                                     func, data);
-      return;
-    }
-
-  closure = g_slice_new (CoglXlibFilterClosure);
-  closure->func = func;
-  closure->data = data;
-
-  ctx->event_filters =
-    g_slist_prepend (ctx->event_filters, closure);
 }
 
 void
-_cogl_xlib_remove_filter (CoglXlibFilterFunc func,
+_cogl_xlib_add_filter (CoglNativeFilterFunc func,
                        void *data)
 {
-  GSList *l, *prev = NULL;
-
   _COGL_GET_CONTEXT (ctx, NO_RETVAL);
 
-  if (!ctx->stub_winsys)
+  cogl_renderer_add_native_filter (ctx->display->renderer, func, data);
-    {
+}
-      cogl_renderer_xlib_remove_filter (ctx->display->renderer,
-                                        func, data);
-      return;
-    }
 
-  for (l = ctx->event_filters; l; prev = l, l = l->next)
+void
-    {
+_cogl_xlib_remove_filter (CoglNativeFilterFunc func,
-      CoglXlibFilterClosure *closure = l->data;
+                          void *data)
+{
+  _COGL_GET_CONTEXT (ctx, NO_RETVAL);
 
-      if (closure->func == func && closure->data == data)
+  cogl_renderer_remove_native_filter (ctx->display->renderer, func, data);
-        {
-          g_slice_free (CoglXlibFilterClosure, closure);
-          if (prev)
-            prev->next = g_slist_delete_link (prev->next, l);
-          else
-            ctx->event_filters =
-              g_slist_delete_link (ctx->event_filters, l);
-          break;
-        }
-    }
 }
 
 static int

clutter/cogl/cogl/cogl-xlib.h

@@ -78,7 +78,7 @@ cogl_xlib_set_display (Display *display);
  * Stability: Unstable
  */
 #define cogl_xlib_handle_event cogl_xlib_handle_event_EXP
-CoglXlibFilterReturn
+CoglFilterReturn
 cogl_xlib_handle_event (XEvent *xevent);
 
 #endif /* __COGL_XLIB_H__ */

clutter/cogl/cogl/winsys/cogl-texture-pixmap-x11.c

@@ -203,13 +203,14 @@ process_damage_event (CoglTexturePixmapX11 *tex_pixmap,
 #endif
 }
 
-static CoglXlibFilterReturn
+static CoglFilterReturn
-_cogl_texture_pixmap_x11_filter (XEvent *event, gpointer data)
+_cogl_texture_pixmap_x11_filter (void *native_event, void *data)
 {
+  XEvent *event = native_event;
   CoglTexturePixmapX11 *tex_pixmap = data;
   int damage_base;
 
-  _COGL_GET_CONTEXT (ctxt, COGL_XLIB_FILTER_CONTINUE);
+  _COGL_GET_CONTEXT (ctxt, COGL_FILTER_CONTINUE);
 
   damage_base = _cogl_xlib_get_damage_base ();
   if (event->type == damage_base + XDamageNotify)
@@ -220,7 +221,7 @@ _cogl_texture_pixmap_x11_filter (XEvent *event, gpointer data)
         process_damage_event (tex_pixmap, damage_event);
     }
 
-  return COGL_XLIB_FILTER_CONTINUE;
+  return COGL_FILTER_CONTINUE;
 }
 
 #ifdef COGL_HAS_GLX_SUPPORT

clutter/cogl/cogl/winsys/cogl-winsys-glx.c

@@ -219,9 +219,10 @@ notify_swap_buffers (CoglContext *context, GLXDrawable drawable)
     }
 }
 
-static CoglXlibFilterReturn
+static CoglFilterReturn
-glx_event_filter_cb (XEvent *xevent, void *data)
+glx_event_filter_cb (void *native_event, void *data)
 {
+  XEvent *xevent = native_event;
   CoglContext *context = data;
 #ifdef GLX_INTEL_swap_event
   CoglRendererGLX *glx_renderer;
@@ -242,7 +243,7 @@ glx_event_filter_cb (XEvent *xevent, void *data)
         }
 
       /* we let ConfigureNotify pass through */
-      return COGL_XLIB_FILTER_CONTINUE;
+      return COGL_FILTER_CONTINUE;
     }
 
 #ifdef GLX_INTEL_swap_event
@@ -255,11 +256,11 @@ glx_event_filter_cb (XEvent *xevent, void *data)
       notify_swap_buffers (context, swap_event->drawable);
 
       /* remove SwapComplete events from the queue */
-      return COGL_XLIB_FILTER_REMOVE;
+      return COGL_FILTER_REMOVE;
     }
 #endif /* GLX_INTEL_swap_event */
 
-  return COGL_XLIB_FILTER_CONTINUE;
+  return COGL_FILTER_CONTINUE;
 }
 
 gboolean
@@ -672,7 +673,7 @@ _cogl_winsys_context_init (CoglContext *context, GError **error)
 {
   context->winsys = g_new0 (CoglContextGLX, 1);
 
-  cogl_renderer_xlib_add_filter (context->display->renderer,
+  cogl_renderer_add_native_filter (context->display->renderer,
                                    glx_event_filter_cb,
                                    context);
   update_winsys_features (context);
@@ -683,7 +684,7 @@ _cogl_winsys_context_init (CoglContext *context, GError **error)
 void
 _cogl_winsys_context_deinit (CoglContext *context)
 {
-  cogl_renderer_xlib_remove_filter (context->display->renderer,
+  cogl_renderer_remove_native_filter (context->display->renderer,
                                       glx_event_filter_cb,
                                       context);
   g_free (context->winsys);

clutter/x11/clutter-backend-x11.c

@@ -131,16 +131,16 @@ cogl_xlib_filter (XEvent       *xevent,
                   gpointer      data)
 {
   ClutterX11FilterReturn retval;
-  CoglXlibFilterReturn ret;
+  CoglFilterReturn ret;
 
   ret = cogl_xlib_handle_event (xevent);
   switch (ret)
     {
-    case COGL_XLIB_FILTER_REMOVE:
+    case COGL_FILTER_REMOVE:
       retval = CLUTTER_X11_FILTER_REMOVE;
       break;
 
-    case COGL_XLIB_FILTER_CONTINUE:
+    case COGL_FILTER_CONTINUE:
     default:
       retval = CLUTTER_X11_FILTER_CONTINUE;
       break;