Add ItemDestroyable to the cache limitor

This callback is used when cache limiter needs to remove
some cached objects when running out of limit.

From blender side it's used to keep painted images always
in memory.

This fixes issue when painted images were removing from
the memory after image cache rewrite.

1 files changed, 15 insertions, 0 deletions

diff --git a/source/blender/imbuf/intern/moviecache.c b/source/blender/imbuf/intern/moviecache.c
index c042831a93f..3718cb270c9 100644
--- a/source/blender/imbuf/intern/moviecache.c
+++ b/source/blender/imbuf/intern/moviecache.c
@@ -254,11 +254,26 @@ static int get_item_priority(void *item_v, int default_priority)
 	return priority;
 }
 
+static bool get_item_destroyable(void *item_v)
+{
+	MovieCacheItem *item = (MovieCacheItem *) item_v;
+	/* IB_BITMAPDIRTY means image was modified from inside blender and
+	 * changes are not saved to disk.
+	 *
+	 * Such buffers are never to be freed.
+	 */
+	if (item->ibuf->userflags & IB_BITMAPDIRTY) {
+		return false;
+	}
+	return true;
+}
+
 void IMB_moviecache_init(void)
 {
 	limitor = new_MEM_CacheLimiter(IMB_moviecache_destructor, get_item_size);
 
 	MEM_CacheLimiter_ItemPriority_Func_set(limitor, get_item_priority);
+	MEM_CacheLimiter_ItemDestroyable_Func_set(limitor, get_item_destroyable);
 }
 
 void IMB_moviecache_destruct(void)