[glide] Fix visual craziness when interrupting stage manager fade effect

[Robert Carr <racarr src gnome org>]

commit cadfec830fdc54122e7e149b5a731006a4507a3d
Author: Robert Carr <racarr Valentine localdomain>
Date:   Fri May 7 12:01:20 2010 -0400

    Fix visual craziness when interrupting stage manager fade effect

 libglide/glide-stage-manager-priv.h |    2 ++
 libglide/glide-stage-manager.c      |   21 +++++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)
---
diff --git a/libglide/glide-stage-manager-priv.h b/libglide/glide-stage-manager-priv.h
index 3ba17e5..fd5e53e 100644
--- a/libglide/glide-stage-manager-priv.h
+++ b/libglide/glide-stage-manager-priv.h
@@ -43,6 +43,8 @@ struct _GlideStageManagerPrivate
   GlideUndoManager *undo_manager;
   
   gboolean animating;
+  
+  ClutterTimeline *effect_timeline;
 };
 
 G_END_DECLS
diff --git a/libglide/glide-stage-manager.c b/libglide/glide-stage-manager.c
index b5ca4a4..d6bfa8a 100644
--- a/libglide/glide-stage-manager.c
+++ b/libglide/glide-stage-manager.c
@@ -61,10 +61,21 @@ glide_stage_manager_effect_fade_completed (ClutterTimeline *t, gpointer user_dat
   clutter_actor_hide (a);
 }
 
+static void
+glide_stage_manager_effect_completed (ClutterTimeline *t, gpointer user_data)
+{
+  GlideStageManager *manager = (GlideStageManager *)user_data;
+  manager->priv->effect_timeline = NULL;
+}
+
 static void 
-glide_stage_manager_effect_fade (ClutterActor *a, ClutterActor *b)
+glide_stage_manager_effect_fade (GlideStageManager *manager, 
+				 ClutterActor *a, ClutterActor *b)
 {
   ClutterTimeline *timeline = clutter_timeline_new (350);
+  
+  if (manager->priv->effect_timeline)
+    clutter_timeline_advance (manager->priv->effect_timeline, clutter_timeline_get_duration (manager->priv->effect_timeline));
 
   clutter_actor_show_all (b);
   clutter_actor_raise (b, a);
@@ -75,8 +86,10 @@ glide_stage_manager_effect_fade (ClutterActor *a, ClutterActor *b)
   clutter_actor_animate_with_timeline (b, CLUTTER_LINEAR, timeline, "opacity", 0xff, NULL);
   
   clutter_timeline_start (timeline);
+  manager->priv->effect_timeline = timeline;
   
   g_signal_connect (timeline, "completed", G_CALLBACK (glide_stage_manager_effect_fade_completed), a);
+  g_signal_connect (timeline, "completed", G_CALLBACK (glide_stage_manager_effect_completed), manager);
 }
 
 static void
@@ -205,6 +218,10 @@ glide_stage_manager_set_slide (GlideStageManager *manager,
 			       guint slide)
 {
   GlideSlide *a, *b = glide_document_get_nth_slide (manager->priv->document, slide);
+  
+  if (manager->priv->current_slide == slide)
+    return;
+  
   if (manager->priv->current_slide >= 0 && !(manager->priv->current_slide >= glide_document_get_n_slides (manager->priv->document)))
     a = glide_document_get_nth_slide (manager->priv->document,
 				      manager->priv->current_slide);
@@ -220,7 +237,7 @@ glide_stage_manager_set_slide (GlideStageManager *manager,
     }
   else
     {
-      glide_stage_manager_effect_fade (CLUTTER_ACTOR (a), CLUTTER_ACTOR (b));
+      glide_stage_manager_effect_fade (manager, CLUTTER_ACTOR (a), CLUTTER_ACTOR (b));
     }
   
   manager->priv->current_slide = slide;