Image cache rewrite to using generic movie cache

Summary:
Behaves very much the same as cache for Movie Clip datablock:

- Image now have `MovieCache *cache` field which replaced
  legacy `ListBase ibufs`.

  This allows image datablock to easily keep of image
  buffers which are owned by itself. This field isn't
  saved to the file and getting restored on undo steps.

  However, cache limit is global for movies, sequences
  and image datablocks now. So overall cached image buffers
  size will not go above cache limit size in user
  preferences.

- Image buffers which are marked as BITMAPDIRTY will never
  be freed from the cache.

- Added utility function to iterate over image buffers
  saved in movie cache.

- Movie cache cleanup check callback now have ImBuf argument
  which can be used in a condition of cleanup.

- Added some utility functions which replaces legacy ibufs
  iterations with image cache iteration which happens from
  inside a lock.

- Fixed `image_mem_size()` which was only counting one of
  the buffers if both float and byte buffer present.

Additional notes:

- `BKE_image_get_first_ibuf()` is rather stupid, but direct
  access to ibufs->first was also the same stupid idea.

  Would consider avoid this function is another project.

- There are some places which doesn't look threadsafe, but
  they already were not so much threadsafe anyway before.

  So think not a big deal with solving this later.

Finally solves infinite memory usage by image sequences! :)

Reviewers: brecht, campbellbarton

Reviewed By: brecht

CC: sebastian_k

Differential Revision: http://developer.blender.org/D95

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_image.h b/source/blender/blenkernel/BKE_image.h
index 7b5abbba7f8..b5171f8e0c2 100644
--- a/source/blender/blenkernel/BKE_image.h
+++ b/source/blender/blenkernel/BKE_image.h
@@ -235,6 +235,12 @@ float *BKE_image_get_float_pixels_for_frame(struct Image *image, int frame);
 
 /* Guess offset for the first frame in the sequence */
 int BKE_image_sequence_guess_offset(struct Image *image);
+
+bool BKE_image_is_dirty(struct Image *image);
+void BKE_image_file_format_set(struct Image *image, int ftype);
+bool BKE_image_has_loaded_ibuf(struct Image *image);
+struct ImBuf *BKE_image_get_ibuf_with_name(struct Image *image, const char *name);
+struct ImBuf *BKE_image_get_first_ibuf(struct Image *image);
 #ifdef __cplusplus
 }
 #endif