Code cleanup: use bool flag for direction in clip prefetch

That was nothing really wrong with the old short used for
direction, but that became kinda annoying because of compiler
idiocy which considered direction might have been zero.

Using explicit dual-state flag is more clear anyway.

1 files changed, 9 insertions, 6 deletions

diff --git a/source/blender/editors/space_clip/clip_editor.c b/source/blender/editors/space_clip/clip_editor.c
index 0e1a2f98d40..20e69fce848 100644
--- a/source/blender/editors/space_clip/clip_editor.c
+++ b/source/blender/editors/space_clip/clip_editor.c
@@ -603,7 +603,10 @@ typedef struct PrefetchQueue {
 	int initial_frame, current_frame, start_frame, end_frame;
 	short render_size, render_flag;
 
-	short direction;
+	/* If true prefecthing goes forward in time,
+	 * othwewise it goes backwards in time (starting from current frame).
+	 */
+	bool forward;
 
 	SpinLock spin;
 
@@ -707,17 +710,17 @@ static unsigned char *prefetch_thread_next_frame(PrefetchQueue *queue, MovieClip
 	{
 		int current_frame;
 
-		if (queue->direction > 0) {
+		if (queue->forward) {
 			current_frame = prefetch_find_uncached_frame(clip, queue->current_frame + 1, queue->end_frame,
 			                                             queue->render_size, queue->render_flag, 1);
 			/* switch direction if read frames from current up to scene end frames */
 			if (current_frame > queue->end_frame) {
 				queue->current_frame = queue->initial_frame;
-				queue->direction = -1;
+				queue->forward = false;
 			}
 		}
 
-		if (queue->direction < 0) {
+		if (!queue->forward) {
 			current_frame = prefetch_find_uncached_frame(clip, queue->current_frame - 1, queue->start_frame,
 			                                             queue->render_size, queue->render_flag, -1);
 		}
@@ -732,7 +735,7 @@ static unsigned char *prefetch_thread_next_frame(PrefetchQueue *queue, MovieClip
 
 			queue->current_frame = current_frame;
 
-			if (queue->direction > 0) {
+			if (queue->forward) {
 				frames_processed = queue->current_frame - queue->initial_frame;
 			}
 			else {
@@ -808,7 +811,7 @@ static void start_prefetch_threads(MovieClip *clip, int start_frame, int current
 	queue.end_frame = end_frame;
 	queue.render_size = render_size;
 	queue.render_flag = render_flag;
-	queue.direction = 1;
+	queue.forward = 1;
 
 	queue.stop = stop;
 	queue.do_update = do_update;