[mutter] meta-window-group: Use clutter_stage_get_redraw_clip_bounds

[Neil Roberts <nroberts src gnome org>]

commit 4167ef870c9a03b360bb6d0eead230ea40559927
Author: Neil Roberts <neil linux intel com>
Date:   Wed Jul 13 14:01:05 2011 +0100

    meta-window-group: Use clutter_stage_get_redraw_clip_bounds
    
    Clutter now has some API to get the bounds of the current redraw clip
    so Mutter no longer needs to make direct GL calls to get the scissor
    rect. This should make it more robust against Cogl or Clutter changing
    how it does the clipping.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=654551

 configure.in                       |    2 +-
 src/compositor/meta-window-group.c |   50 +++++++++--------------------------
 2 files changed, 14 insertions(+), 38 deletions(-)
---
diff --git a/configure.in b/configure.in
index 27e650f..25bcc86 100644
--- a/configure.in
+++ b/configure.in
@@ -185,7 +185,7 @@ else
   AC_MSG_ERROR([no. Mutter requires the Xcomposite extension to build.])
 fi
 
-CLUTTER_VERSION=1.2.0
+CLUTTER_VERSION=1.7.5
 CLUTTER_PACKAGE=clutter-1.0
 AC_SUBST(CLUTTER_PACKAGE)
 if $PKG_CONFIG --atleast-version $CLUTTER_VERSION $CLUTTER_PACKAGE ; then
diff --git a/src/compositor/meta-window-group.c b/src/compositor/meta-window-group.c
index 857eab0..c5fc397 100644
--- a/src/compositor/meta-window-group.c
+++ b/src/compositor/meta-window-group.c
@@ -103,11 +103,9 @@ actor_is_untransformed (ClutterActor *actor,
 static void
 meta_window_group_paint (ClutterActor *actor)
 {
-  MetaWindowGroup *window_group = META_WINDOW_GROUP (actor);
   cairo_region_t *visible_region;
-  GLboolean scissor_test;
-  cairo_rectangle_int_t screen_rect = { 0 };
-  cairo_rectangle_int_t scissor_rect;
+  ClutterActor *stage;
+  cairo_rectangle_int_t visible_rect;
   GList *children, *l;
 
   /* We walk the list from top to bottom (opposite of painting order),
@@ -117,39 +115,17 @@ meta_window_group_paint (ClutterActor *actor)
   children = clutter_container_get_children (CLUTTER_CONTAINER (actor));
   children = g_list_reverse (children);
 
-  /* Start off with the full screen area (for a multihead setup, we
-   * might want to use a more accurate union of the monitors to avoid
-   * painting in holes from mismatched monitor sizes. That's just an
-   * optimization, however.)
-   */
-  meta_screen_get_size (window_group->screen, &screen_rect.width, &screen_rect.height);
-
-  /* When doing a partial stage paint, Clutter will set the GL scissor
-   * box to the clip rectangle for the partial repaint. We combine the screen
-   * rectangle with the scissor box to get the region we need to
-   * paint. (Strangely, the scissor box sometimes seems to be bigger
-   * than the stage ... Clutter should probably be clampimg)
-   */
-  glGetBooleanv (GL_SCISSOR_TEST, &scissor_test);
-
-  if (scissor_test)
-    {
-      GLint scissor_box[4];
-      glGetIntegerv (GL_SCISSOR_BOX, scissor_box);
-
-      scissor_rect.x = scissor_box[0];
-      scissor_rect.y = screen_rect.height - (scissor_box[1] + scissor_box[3]);
-      scissor_rect.width = scissor_box[2];
-      scissor_rect.height = scissor_box[3];
-
-      gdk_rectangle_intersect (&scissor_rect, &screen_rect, &scissor_rect);
-    }
-  else
-    {
-      scissor_rect = screen_rect;
-    }
-
-  visible_region = cairo_region_create_rectangle (&scissor_rect);
+  /* Get the clipped redraw bounds from Clutter so that we can avoid
+   * painting shadows on windows that don't need to be painted in this
+   * frame. In the case of a multihead setup with mismatched monitor
+   * sizes, we could intersect this with an accurate union of the
+   * monitors to avoid painting shadows that are visible only in the
+   * holes. */
+  stage = clutter_actor_get_stage (actor);
+  clutter_stage_get_redraw_clip_bounds (CLUTTER_STAGE (stage),
+                                        &visible_rect);
+
+  visible_region = cairo_region_create_rectangle (&visible_rect);
 
   for (l = children; l; l = l->next)
     {