From a60ccd3672467efb454b121993febc36f33cbc79 Mon Sep 17 00:00:00 2001
From: Alexander Larsson <alexl@redhat.com>
Date: Wed, 15 May 2013 10:55:59 +0200
Subject: [PATCH] GdkWindow: Fix shape handling for native windows

We don't track the full clip for each window anymore, as this
is not useful when no windows are opaque. However, we still
need the full clip for the shape, so its calculated manually.

However, it was previously only recalculated when the clip changes
which doesn't correctly handle the case of a sibling geometry changing.

So, instead of doing this directly when geometry changes we just
set a bit in the toplevel whenever some window geometry changes, and
we then handle this in process_updates, updating the shape for all
native windows. This should be ok performance-wise because we don't
expect a lot of native children.
---
 gdk/gdkinternals.h |  1 +
 gdk/gdkwindow.c    | 58 +++++++++++++++++++++++++++-------------------
 2 files changed, 35 insertions(+), 24 deletions(-)

diff --git a/gdk/gdkinternals.h b/gdk/gdkinternals.h
index 3f2d1a4b95..e7eb9d5b40 100644
--- a/gdk/gdkinternals.h
+++ b/gdk/gdkinternals.h
@@ -226,6 +226,7 @@ struct _GdkWindow
   guint viewable : 1; /* mapped and all parents mapped */
   guint applied_shape : 1;
   guint in_update : 1;
+  guint geometry_dirty : 1;
   GdkFullscreenMode fullscreen_mode;
 
   /* The GdkWindow that has the impl, ref:ed if another window.
diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index 63128bd998..04ca4eaeba 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -616,7 +616,7 @@ remove_sibling_overlapped_area (GdkWindow *window,
 
   parent = window->parent;
 
-  if (parent == NULL)
+  if (gdk_window_is_toplevel (window))
     return;
 
   /* Convert from from window coords to parent coords */
@@ -665,6 +665,8 @@ remove_sibling_overlapped_area (GdkWindow *window,
       cairo_region_destroy (child_region);
     }
 
+  remove_sibling_overlapped_area (parent, region);
+
   /* Convert back to window coords */
   cairo_region_translate (region, -window->x, -window->y);
 }
@@ -1004,10 +1006,6 @@ recompute_visible_regions_internal (GdkWindow *private,
 	}
     }
 
-  if (clip_region_changed &&
-      should_apply_clip_as_shape (private))
-    apply_clip_as_shape (private);
-
   if (private->cairo_surface && gdk_window_has_impl (private))
     {
       GdkWindowImplClass *iface = GDK_WINDOW_IMPL_GET_CLASS (private->impl);
@@ -1040,6 +1038,11 @@ static void
 recompute_visible_regions (GdkWindow *private,
 			   gboolean recalculate_children)
 {
+  GdkWindow *toplevel;
+
+  toplevel = gdk_window_get_toplevel (private);
+  toplevel->geometry_dirty = TRUE;
+
   recompute_visible_regions_internal (private,
 				      TRUE,
 				      recalculate_children);
@@ -1508,7 +1511,7 @@ gdk_window_reparent (GdkWindow *window,
 {
   GdkWindow *old_parent;
   GdkScreen *screen;
-  gboolean show, was_mapped, applied_clip_as_shape;
+  gboolean show, was_mapped;
   gboolean do_reparent_to_impl;
   GdkEventMask old_native_event_mask;
   GdkWindowImplClass *impl_class;
@@ -1548,8 +1551,6 @@ gdk_window_reparent (GdkWindow *window,
       new_parent->window_type == GDK_WINDOW_FOREIGN)
     gdk_window_ensure_native (window);
 
-  applied_clip_as_shape = should_apply_clip_as_shape (window);
-
   old_native_event_mask = 0;
   do_reparent_to_impl = FALSE;
   if (gdk_window_has_impl (window))
@@ -1661,13 +1662,6 @@ gdk_window_reparent (GdkWindow *window,
 
   recompute_visible_regions (window, FALSE);
 
-  /* We used to apply the clip as the shape, but no more.
-     Reset this to the real shape */
-  if (gdk_window_has_impl (window) &&
-      applied_clip_as_shape &&
-      !should_apply_clip_as_shape (window))
-    apply_shape (window, window->shape);
-
   if (do_reparent_to_impl)
     reparent_to_impl (window);
   else
@@ -1766,11 +1760,6 @@ gdk_window_ensure_native (GdkWindow *window)
 
   recompute_visible_regions (window, FALSE);
 
-  /* The shape may not have been set, as the clip region doesn't actually
-     change, so do it here manually */
-  if (should_apply_clip_as_shape (window))
-    apply_clip_as_shape (window);
-
   reparent_to_impl (window);
 
   if (!window->input_only)
@@ -3416,6 +3405,23 @@ _gdk_window_process_updates_recurse (GdkWindow *window,
   g_list_free_full (children, g_object_unref);
 }
 
+static void
+gdk_window_update_native_shapes (GdkWindow *window)
+{
+  GdkWindow *child;
+  GList *l;
+
+  if (should_apply_clip_as_shape (window))
+    apply_clip_as_shape (window);
+
+  for (l = window->native_children; l != NULL; l = l->next)
+    {
+      child = l->data;
+
+      gdk_window_update_native_shapes (child);
+    }
+}
+
 /* Process and remove any invalid area on the native window by creating
  * expose events for the window and all non-native descendants.
  */
@@ -3425,6 +3431,14 @@ gdk_window_process_updates_internal (GdkWindow *window)
   GdkWindowImplClass *impl_class;
   gboolean save_region = FALSE;
   GdkRectangle clip_box;
+  GdkWindow *toplevel;
+
+  toplevel = gdk_window_get_toplevel (window);
+  if (toplevel->geometry_dirty)
+    {
+      gdk_window_update_native_shapes (toplevel);
+      toplevel->geometry_dirty = FALSE;
+    }
 
   /* Ensure the window lives while updating it */
   g_object_ref (window);
@@ -6280,10 +6294,6 @@ gdk_window_shape_combine_region (GdkWindow       *window,
 
   recompute_visible_regions (window, FALSE);
 
-  if (gdk_window_has_impl (window) &&
-      !should_apply_clip_as_shape (window))
-    apply_shape (window, window->shape);
-
   if (old_region)
     {
       new_region = cairo_region_copy (window->clip_region);