2006-06-04 Matthew Allum <mallum@openedhand.com>

* clutter/clutter-element.c:
        * clutter/clutter-group.c:
        * clutter/clutter-group.h:
        Work more on depth ( Z ) setting with sorting.

        * clutter/clutter-main.c: (clutter_redraw):
        Experiment with glXWaitVideoSyncSGI. Currently disabled.

ChangeLog

@@ -1,3 +1,13 @@
+2006-06-04  Matthew Allum  <mallum@openedhand.com>
+
+	* clutter/clutter-element.c:
+	* clutter/clutter-group.c:
+	* clutter/clutter-group.h:
+	Work more on depth ( Z ) setting with sorting. 
+
+	* clutter/clutter-main.c: (clutter_redraw):
+	Experiment with glXWaitVideoSyncSGI. Currently disabled.
+
 2006-06-02  Matthew Allum  <mallum@openedhand.com>
 
 	* clutter/clutter-element.h:

clutter/clutter-element.c

@@ -56,7 +56,7 @@ struct _ClutterElementPrivate
   gint                    z; 	/* to element box ? */
 
   guint8                  opacity;
-  ClutterElement         *parent_element;
+  ClutterElement         *parent_element; /* This should always be a group */
   gchar                  *name;
   guint32                 id; 	/* Unique ID */
 };
@@ -291,7 +291,8 @@ clutter_element_paint (ClutterElement *self)
 		     (float)(-1.0 * self->priv->z) - self->priv->rxz);
     }
 
-  
+  if (self->priv->z)
+    glTranslatef ( 0.0, 0.0, (float)self->priv->z);
 
   if (klass->paint)
     (klass->paint) (self);
@@ -937,9 +938,15 @@ static void
 depth_sorter_foreach (ClutterElement *element, gpointer user_data)
 {
   ClutterElement *element_to_sort = CLUTTER_ELEMENT(user_data);
+  gint            z_copy;
+
+  z_copy = element->priv->z;
 
   if (element_to_sort->priv->z > element->priv->z) 
-    clutter_element_raise (element_to_sort, element);
+    {
+      clutter_element_raise (element_to_sort, element);
+      element->priv->z = z_copy;
+    }
 }
 
 /**
@@ -953,20 +960,19 @@ void
 clutter_element_set_depth (ClutterElement *self,
                            gint            depth)
 {
-  /* Sets Z value. Note probably need to sort via stacking order
-   * so rendering correct with alpha values. 
-  */
+  /* Sets Z value.*/
   self->priv->z = depth;
 
   if (self->priv->parent_element)
     {
-      /* Fix stacking ordering so rendering correct */
-
-      clutter_element_lower_bottom (self);
-
-      clutter_group_foreach (CLUTTER_GROUP(self->priv->parent_element),
-			     depth_sorter_foreach,
-			     (gpointer)self);
+      /* We need to resort the group stacking order as to
+       * correctly render alpha values. 
+       *
+       * FIXME: This is sub optimal. maybe queue the the sort 
+       *        before stacking  
+      */
+      clutter_group_sort_depth_order 
+	(CLUTTER_GROUP(self->priv->parent_element));
     }
 }
 

clutter/clutter-group.c

@@ -205,6 +205,7 @@ clutter_group_new (void)
 GList*
 clutter_group_get_children (ClutterGroup *self)
 {
+  /* FIXME: remane get_actors() */
   g_return_val_if_fail (CLUTTER_IS_GROUP (self), NULL);
 
   return g_list_copy(self->priv->children);
@@ -294,9 +295,7 @@ clutter_group_add (ClutterGroup *self, ClutterElement *element)
   /* below refs */
   clutter_element_set_parent (element, CLUTTER_ELEMENT(self));
 
-  /* FIXME: Force Sort any Z ordering, or set to 0 ? */
-  if (clutter_element_get_depth (element) != 0)
-    clutter_element_set_depth (element, clutter_element_get_depth (element));
+  clutter_group_sort_depth_order (self); 
 }
 
 /**
@@ -442,7 +441,7 @@ clutter_group_raise (ClutterGroup     *self,
 		     ClutterElement *sibling)
 {
   ClutterGroupPrivate *priv;
-  gint               pos;
+  gint                 pos;
 
   g_return_if_fail (element != sibling);
 
@@ -453,9 +452,27 @@ clutter_group_raise (ClutterGroup     *self,
   priv->children = g_list_remove (priv->children, element); 
 
   if (sibling == NULL)
-    priv->children = g_list_append (priv->children, element);
+    {
+      GList *last_item;
+      /* Raise top */
+      last_item = g_list_last (priv->children);
+      sibling = last_item->data;
+      priv->children = g_list_append (priv->children, element);
+    }
   else
-    priv->children = g_list_insert (priv->children, element, pos);
+    {
+      priv->children = g_list_insert (priv->children, element, pos);
+    }
+
+  /* set Z ordering a value below, this will then call sort
+   * as values are equal ordering shouldn't change but Z
+   * values will be correct.
+   * FIXME: optimise
+   */
+  if (clutter_element_get_depth(sibling) != clutter_element_get_depth(element))
+    clutter_element_set_depth (element,
+			       clutter_element_get_depth(sibling));
+
 }
 
 void
@@ -475,7 +492,55 @@ clutter_group_lower (ClutterGroup     *self,
   priv->children = g_list_remove (priv->children, element); 
 
   if (sibling == NULL)
-    priv->children = g_list_prepend (priv->children, element);
+    {
+      GList *last_item;
+      /* Raise top */
+      last_item = g_list_first (priv->children);
+      sibling = last_item->data;
+
+      priv->children = g_list_prepend (priv->children, element);
+    }
   else
     priv->children = g_list_insert (priv->children, element, pos);
+
+  /* See comment in group_raise for this */
+  if (clutter_element_get_depth(sibling) != clutter_element_get_depth(element))
+    clutter_element_set_depth (element,
+			       clutter_element_get_depth(sibling));
+}
+
+static gint 
+sort_z_order (gconstpointer a, gconstpointer b)
+{
+  if (clutter_element_get_depth (CLUTTER_ELEMENT(a)) 
+         == clutter_element_get_depth (CLUTTER_ELEMENT(b))) 
+    return 0;
+
+  if (clutter_element_get_depth (CLUTTER_ELEMENT(a)) 
+        > clutter_element_get_depth (CLUTTER_ELEMENT(b))) 
+    return 1;
+
+  return -1;
+}
+
+/**
+ * clutter_group_sort_z_order:
+ * @self: A #ClutterGroup
+ *
+ * Sorts a #ClutterGroup's children by there depth value.  
+ * This function should not be used by applications. 
+ **/
+void
+clutter_group_sort_depth_order (ClutterGroup *self)
+{
+  ClutterGroupPrivate *priv;
+
+  g_return_if_fail (CLUTTER_IS_GROUP(self));
+
+  priv = self->priv;
+
+  priv->children = g_list_sort (priv->children, sort_z_order);
+
+  if (CLUTTER_ELEMENT_IS_VISIBLE (CLUTTER_ELEMENT(self)))
+    clutter_element_queue_redraw (CLUTTER_ELEMENT(self));
 }

clutter/clutter-group.h

@@ -125,6 +125,9 @@ clutter_group_lower (ClutterGroup     *self,
 		     ClutterElement *element, 
 		     ClutterElement *sibling);
 
+void
+clutter_group_sort_depth_order (ClutterGroup *self);
+
 G_END_DECLS
 
 #endif

clutter/clutter-main.c

@@ -260,6 +260,14 @@ clutter_redraw ()
 
   if (clutter_stage_get_xwindow (stage))
     {
+#if 0
+      unsigned int retraceCount;
+
+      // Wait for vertical retrace
+      // glXGetVideoSyncSGI(&retraceCount);
+      // glXWaitVideoSyncSGI(2, (retraceCount+1)%2, &retraceCount);
+      glXWaitVideoSyncSGI(1, 0, &retraceCount);
+#endif
       glXSwapBuffers(ctx->xdpy, clutter_stage_get_xwindow (stage));  
     }
   else