1 files changed, 50 insertions, 58 deletions

diff --git a/clutter/cogl/clutter-stage-cogl.c b/clutter/cogl/clutter-stage-cogl.c
index 882189d46..25e95f0ee 100644
--- a/clutter/cogl/clutter-stage-cogl.c
+++ b/clutter/cogl/clutter-stage-cogl.c
@@ -393,6 +393,15 @@ clutter_stage_cogl_get_redraw_clip_bounds (ClutterStageWindow    *stage_window,
   return FALSE;
 }
 
+static inline gboolean
+valid_buffer_age (ClutterStageCogl *stage_cogl, int age)
+{
+  if (age <= 0 || stage_cogl->dirty_backbuffer)
+    return FALSE;
+
+  return age < MIN (stage_cogl->damage_index, DAMAGE_HISTORY_MAX);
+}
+
 /* XXX: This is basically identical to clutter_stage_glx_redraw */
 static void
 clutter_stage_cogl_redraw (ClutterStageWindow *stage_window)
@@ -469,65 +478,47 @@ clutter_stage_cogl_redraw (ClutterStageWindow *stage_window)
 
   window_scale = _clutter_stage_window_get_scale_factor (stage_window);
 
-  if (use_clipped_redraw)
+  if (has_buffer_age)
     {
-      if (has_buffer_age)
-      {
-        int age = cogl_onscreen_get_buffer_age (stage_cogl->onscreen);
-        cairo_rectangle_int_t *current_damage;
-
-        current_damage = g_new0 (cairo_rectangle_int_t, 1);
-        current_damage->x = clip_region->x;
-        current_damage->y = clip_region->y;
-        current_damage->width = clip_region->width;
-        current_damage->height = clip_region->height;
-
-        stage_cogl->damage_history = g_slist_prepend (stage_cogl->damage_history, current_damage);
-
-        if (age != 0 && !stage_cogl->dirty_backbuffer && g_slist_length (stage_cogl->damage_history) > age)
-          {
-            int i = 0;
-            GSList *tmp = NULL;
-            /* We skip the first entry because it is the clip_region itself */
-            for (tmp = stage_cogl->damage_history->next; tmp; tmp = tmp->next)
-              {
-                _clutter_util_rectangle_union (clip_region, tmp->data, clip_region);
-                i++;
-                if (i == age)
-                  {
-                    g_slist_free_full (tmp->next, g_free);
-                    tmp->next = NULL;
-                  }
-              }
-
-            force_swap = TRUE;
-
-            CLUTTER_NOTE (CLIPPING, "Reusing back buffer - repairing region: x=%d, y=%d, width=%d, height=%d\n",
-                          clip_region->x,
-                          clip_region->y,
-                          clip_region->width,
-                          clip_region->height);
-
-          }
-        else if (age == 0 || stage_cogl->dirty_backbuffer)
-          {
-            CLUTTER_NOTE (CLIPPING, "Invalid back buffer: Resetting damage history list.\n");
-            g_slist_free_full (stage_cogl->damage_history, g_free);
-            stage_cogl->damage_history = NULL;
-          }
-
-      }
-    }
-  else if (has_buffer_age)
-    {
-      CLUTTER_NOTE (CLIPPING, "Unclipped redraw: Resetting damage history list.\n");
-      g_slist_free_full (stage_cogl->damage_history, g_free);
-      stage_cogl->damage_history = NULL;
+      cairo_rectangle_int_t *current_damage =
+	&stage_cogl->damage_history[DAMAGE_HISTORY (stage_cogl->damage_index++)];
+
+      if (use_clipped_redraw)
+	{
+	  int age = cogl_onscreen_get_buffer_age (stage_cogl->onscreen), i;
+
+	  *current_damage = *clip_region;
+
+	  if (valid_buffer_age (stage_cogl, age))
+	    {
+	      for (i = 1; i <= age; i++)
+		_clutter_util_rectangle_union (clip_region,
+					       &stage_cogl->damage_history[DAMAGE_HISTORY (stage_cogl->damage_index - i - 1)],
+					       clip_region);
+
+	      CLUTTER_NOTE (CLIPPING, "Reusing back buffer(age=%d) - repairing region: x=%d, y=%d, width=%d, height=%d\n",
+			    age,
+			    clip_region->x,
+			    clip_region->y,
+			    clip_region->width,
+			    clip_region->height);
+	      force_swap = TRUE;
+	    }
+	  else
+	    {
+	      CLUTTER_NOTE (CLIPPING, "Invalid back buffer(age=%d): forcing full redraw\n", age);
+	      use_clipped_redraw = FALSE;
+	    }
+	}
+      else
+	{
+	  current_damage->x = 0;
+	  current_damage->y = 0;
+	  current_damage->width  = geom.width;
+	  current_damage->height = geom.height;
+	}
     }
 
-  if (has_buffer_age && !force_swap)
-    use_clipped_redraw = FALSE;
-
   if (use_clipped_redraw)
     {
       CoglFramebuffer *fb = COGL_FRAMEBUFFER (stage_cogl->onscreen);
@@ -704,7 +695,7 @@ clutter_stage_cogl_get_dirty_pixel (ClutterStageWindow *stage_window,
   ClutterStageCogl *stage_cogl = CLUTTER_STAGE_COGL (stage_window);
   gboolean has_buffer_age = cogl_clutter_winsys_has_feature (COGL_WINSYS_FEATURE_BUFFER_AGE);
 
-  if ((stage_cogl->damage_history == NULL && has_buffer_age) || !has_buffer_age)
+  if (!has_buffer_age)
     {
       *x = 0;
       *y = 0;
@@ -712,7 +703,8 @@ clutter_stage_cogl_get_dirty_pixel (ClutterStageWindow *stage_window,
   else
     {
       cairo_rectangle_int_t *rect;
-      rect = (cairo_rectangle_int_t *) (stage_cogl->damage_history->data);
+
+      rect = &stage_cogl->damage_history[DAMAGE_HISTORY (stage_cogl->damage_index-1)];
       *x = rect->x;
       *y = rect->y;
     }