/* returns true if early out is possible */
static bool prefetch_check_early_out(const bContext *C)
{
SpaceClip *sc = CTX_wm_space_clip(C);
MovieClip *clip = ED_space_clip_get_clip(sc);
int first_uncached_frame, end_frame;
int clip_len;
clip_len = BKE_movieclip_get_duration(clip);
/* check whether all the frames from prefetch range are cached */
end_frame = prefetch_get_final_frame(C);
first_uncached_frame =
prefetch_find_uncached_frame(clip, sc->user.framenr, end_frame,
sc->user.render_size, sc->user.render_flag, 1);
if (first_uncached_frame > end_frame || first_uncached_frame == clip_len) {
int start_frame = prefetch_get_start_frame(C);
first_uncached_frame =
prefetch_find_uncached_frame(clip, sc->user.framenr, start_frame,
sc->user.render_size, sc->user.render_flag, -1);
if (first_uncached_frame < start_frame)
return true;
}
return false;
}
/* get memory buffer for first uncached frame within prefetch frame range */
static unsigned char *prefetch_thread_next_frame(
PrefetchQueue *queue, MovieClip *clip,
size_t *r_size, int *r_current_frame)
{
unsigned char *mem = NULL;
BLI_spin_lock(&queue->spin);
if (!*queue->stop && !check_prefetch_break() &&
IN_RANGE_INCL(queue->current_frame, queue->start_frame, queue->end_frame))
{
int current_frame;
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->forward = false;
}
}
if (!queue->forward) {
current_frame = prefetch_find_uncached_frame(clip, queue->current_frame - 1, queue->start_frame,
queue->render_size, queue->render_flag, -1);
}
if (IN_RANGE_INCL(current_frame, queue->start_frame, queue->end_frame)) {
int frames_processed;
mem = prefetch_read_file_to_memory(clip, current_frame, queue->render_size,
queue->render_flag, r_size);
*r_current_frame = current_frame;
queue->current_frame = current_frame;
if (queue->forward) {
frames_processed = queue->current_frame - queue->initial_frame;
}
else {
frames_processed = (queue->end_frame - queue->initial_frame) +
(queue->initial_frame - queue->current_frame);
}
*queue->do_update = 1;
*queue->progress = (float)frames_processed / (queue->end_frame - queue->start_frame);
}
}
BLI_spin_unlock(&queue->spin);
return mem;
}
