Refactor of proxies build operators

Split proxy build operator into three parts:
- Prepare context (IMB_anim_index_rebuild_context) which prepares all
  needed data and stores it in an anonymous structure used by specific
  builder lately.
- Build proxies/timecodes into temporary files (IMB_anim_index_rebuild)
  This function will build all selected proxies/timecodes into a temporary
  files so old proxies will be still available during building.
- Finish building proxies (IMB_anim_index_rebuild_finish) which copies
  temporary files over old proxies filed and releases all resources used
  by a context.

Context creation and finishing building happens in a main thread so
it's easy and safe to close all opened handles of proxies files and
refresh cache after rebuilding is finished.

This should finally fix #30315: Temporary proxy files are not erased and old proxys are not updated if the proxy is built more then once (windows)

1 files changed, 5 insertions, 2 deletions

diff --git a/source/blender/blenkernel/BKE_sequencer.h b/source/blender/blenkernel/BKE_sequencer.h
index 5c6058b1453..3cb8e91ac00 100644
--- a/source/blender/blenkernel/BKE_sequencer.h
+++ b/source/blender/blenkernel/BKE_sequencer.h
@@ -40,6 +40,8 @@ struct Strip;
 struct StripElem;
 struct bSound;
 
+struct SeqIndexBuildContext;
+
 #define BUILD_SEQAR_COUNT_NOTHING  0
 #define BUILD_SEQAR_COUNT_CURRENT  1
 #define BUILD_SEQAR_COUNT_CHILDREN 2
@@ -194,9 +196,10 @@ void update_changed_seq_and_deps(struct Scene *scene, struct Sequence *changed_s
 int input_have_to_preprocess(
 	SeqRenderData context, struct Sequence * seq, float cfra);
 
-void seq_proxy_rebuild(struct Main * bmain, 
-                       struct Scene *scene, struct Sequence * seq,
+struct SeqIndexBuildContext *seq_proxy_rebuild_context(struct Main *bmain, struct Scene *scene, struct Sequence *seq);
+void seq_proxy_rebuild(struct SeqIndexBuildContext *context,
                        short *stop, short *do_update, float *progress);
+void seq_proxy_rebuild_finish(struct SeqIndexBuildContext *context, short stop);
 
 
 /* **********************************************************************