diff --git a/ChangeLog b/ChangeLog
index 34d85ba6c6..30a3442b6b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2008-11-05  Michael Natterer  <mitch@gimp.org>
+
+	* app/core/gimpdrawablestack.[ch]: add new function
+	gimp_drawable_stack_invalidate_previews() which does just what it
+	says.
+
+	* app/core/gimpimage.[ch]: merge invalidate_layer_previews() and
+	invalidate_channels_previews() into a single invalidate_previews()
+	and replace all calls to the old functions by calls to
+	gimp_drawable_stack_invalidate_previews().
+
+	* app/file/file-open.c: changed accordingly.
+
 2008-11-05  Michael Natterer  <mitch@gimp.org>
 
 	* app/core/gimpimage-convert.c (gimp_image_convert): remove call
diff --git a/app/core/gimpdrawablestack.c b/app/core/gimpdrawablestack.c
index 6550b8841e..236cbda632 100644
--- a/app/core/gimpdrawablestack.c
+++ b/app/core/gimpdrawablestack.c
@@ -281,6 +281,16 @@ gimp_drawable_stack_get_graph (GimpDrawableStack *stack)
   return stack->graph;
 }
 
+void
+gimp_drawable_stack_invalidate_previews (GimpDrawableStack *stack)
+{
+  g_return_if_fail (GIMP_IS_DRAWABLE_STACK (stack));
+
+  gimp_container_foreach (GIMP_CONTAINER (stack),
+                          (GFunc) gimp_viewable_invalidate_preview,
+                          NULL);
+}
+
 
 /*  private functions  */
 
diff --git a/app/core/gimpdrawablestack.h b/app/core/gimpdrawablestack.h
index a617d2372e..e4cd2f80b7 100644
--- a/app/core/gimpdrawablestack.h
+++ b/app/core/gimpdrawablestack.h
@@ -53,10 +53,12 @@ struct _GimpDrawableStackClass
 };
 
 
-GType           gimp_drawable_stack_get_type  (void) G_GNUC_CONST;
-GimpContainer * gimp_drawable_stack_new       (GType              drawable_type);
+GType           gimp_drawable_stack_get_type            (void) G_GNUC_CONST;
+GimpContainer * gimp_drawable_stack_new                 (GType              drawable_type);
 
-GeglNode      * gimp_drawable_stack_get_graph (GimpDrawableStack *stack);
+GeglNode      * gimp_drawable_stack_get_graph           (GimpDrawableStack *stack);
+
+void            gimp_drawable_stack_invalidate_previews (GimpDrawableStack *stack);
 
 
 #endif  /*  __GIMP_DRAWABLE_STACK_H__  */
diff --git a/app/core/gimpimage.c b/app/core/gimpimage.c
index 7620ddfc56..7f78bff6ef 100644
--- a/app/core/gimpimage.c
+++ b/app/core/gimpimage.c
@@ -736,11 +736,11 @@ gimp_image_constructor (GType                  type,
                     image);
 
   g_signal_connect_object (config, "notify::transparency-type",
-                           G_CALLBACK (gimp_image_invalidate_layer_previews),
-                           image, G_CONNECT_SWAPPED);
+                           G_CALLBACK (gimp_drawable_stack_invalidate_previews),
+                           image->layers, G_CONNECT_SWAPPED);
   g_signal_connect_object (config, "notify::transparency-size",
-                           G_CALLBACK (gimp_image_invalidate_layer_previews),
-                           image, G_CONNECT_SWAPPED);
+                           G_CALLBACK (gimp_drawable_stack_invalidate_previews),
+                           image->layers, G_CONNECT_SWAPPED);
   g_signal_connect_object (config, "notify::layer-previews",
                            G_CALLBACK (gimp_viewable_size_changed),
                            image, G_CONNECT_SWAPPED);
@@ -1136,7 +1136,7 @@ gimp_image_real_colormap_changed (GimpImage *image,
                          gimp_image_get_width  (image),
                          gimp_image_get_height (image));
 
-      gimp_image_invalidate_layer_previews (image);
+      gimp_drawable_stack_invalidate_previews (GIMP_DRAWABLE_STACK (image->layers));
     }
 }
 
@@ -3799,21 +3799,10 @@ gimp_image_coords_in_active_pickable (GimpImage        *image,
 }
 
 void
-gimp_image_invalidate_layer_previews (GimpImage *image)
+gimp_image_invalidate_previews (GimpImage *image)
 {
   g_return_if_fail (GIMP_IS_IMAGE (image));
 
-  gimp_container_foreach (image->layers,
-                          (GFunc) gimp_viewable_invalidate_preview,
-                          NULL);
-}
-
-void
-gimp_image_invalidate_channel_previews (GimpImage *image)
-{
-  g_return_if_fail (GIMP_IS_IMAGE (image));
-
-  gimp_container_foreach (image->channels,
-                          (GFunc) gimp_viewable_invalidate_preview,
-                          NULL);
+  gimp_drawable_stack_invalidate_previews (GIMP_DRAWABLE_STACK (image->layers));
+  gimp_drawable_stack_invalidate_previews (GIMP_DRAWABLE_STACK (image->channels));
 }
diff --git a/app/core/gimpimage.h b/app/core/gimpimage.h
index 9c7a56c121..1c1233ebea 100644
--- a/app/core/gimpimage.h
+++ b/app/core/gimpimage.h
@@ -551,8 +551,7 @@ gboolean    gimp_image_coords_in_active_pickable (GimpImage          *image,
                                                   gboolean            sample_merged,
                                                   gboolean            selected_only);
 
-void        gimp_image_invalidate_layer_previews (GimpImage          *image);
-void      gimp_image_invalidate_channel_previews (GimpImage          *image);
+void            gimp_image_invalidate_previews   (GimpImage          *image);
 
 
 #endif /* __GIMP_IMAGE_H__ */
diff --git a/app/file/file-open.c b/app/file/file-open.c
index 63b9a89711..ac6a5e8ef7 100644
--- a/app/file/file-open.c
+++ b/app/file/file-open.c
@@ -552,8 +552,7 @@ file_open_sanitize_image (GimpImage *image,
   gimp_image_flush (image);
 
   /* same for drawable previews */
-  gimp_image_invalidate_layer_previews (image);
-  gimp_image_invalidate_channel_previews (image);
+  gimp_image_invalidate_previews (image);
 }
 
 /* Converts items from one image to another */