Recode of the "Set Scene chaining" patch from Nathan.

- code for detecting loops was overly complex, and detected loops wrong
  even (when chains partially overlap it gave error)
- that code could NULLify sets of other scenes than the one you tested
- and that code should be in blenkernel, so it can be called in more
  locations, like fixing potential loops in old files

- the code for looping over the chained scenes was bad too, I created a
  nice #define to keep code readable. (See SETLOOPER in BKE_scene.h)

ALso fixes reports in tracker :)

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_scene.h b/source/blender/blenkernel/BKE_scene.h
index 2f1dfb66250..f7fa8436e4f 100644
--- a/source/blender/blenkernel/BKE_scene.h
+++ b/source/blender/blenkernel/BKE_scene.h
@@ -73,6 +73,9 @@ struct Base *scene_add_base(struct Scene *sce, struct Object *ob);
 void scene_deselect_all(struct Scene *sce);
 void scene_select_base(struct Scene *sce, struct Base *selbase);
 
+/* checks for cycle, returns 1 if it's all OK */
+int scene_check_setscene(struct Scene *sce);
+
 void scene_update_for_newframe(struct Scene *sce, unsigned int lay);
 
 void scene_add_render_layer(struct Scene *sce);