Depsgraph/Python: callbacks and properties to detect datablock changes

* Adds two new python handlers: scene_update_pre() and scene_update_post()
  These run before and after Blender does a scene update on making modifications
  to the scene.
* Datablocks now have an is_updated property. This will be set to true in the
  above callbacks if the datablock was tagged to be updated. This works for the
  most common datablocks used for rendering: object, material, world, lamsp,
  texture, mesh, curve.
* Datablock collections also have an is_updated property. If this is set, it
  means one datablock of this type was added, removed or modified. It's also
  useful as a quick check to avoid looping over all datablocks.
* RenderEngine.view_update() can also check these properties, for interactive
  viewport rendering.

http://wiki.blender.org/index.php/Dev:2.6/Source/Render/UpdateAPI

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_callbacks.h b/source/blender/blenlib/BLI_callbacks.h
index 5322ce04a2e..7e4fad54cda 100644
--- a/source/blender/blenlib/BLI_callbacks.h
+++ b/source/blender/blenlib/BLI_callbacks.h
@@ -47,6 +47,8 @@ typedef enum {
 	BLI_CB_EVT_LOAD_POST,
 	BLI_CB_EVT_SAVE_PRE,
 	BLI_CB_EVT_SAVE_POST,
+	BLI_CB_EVT_SCENE_UPDATE_PRE,
+	BLI_CB_EVT_SCENE_UPDATE_POST,
 	BLI_CB_EVT_TOT
 } eCbEvent;