[Bf-blender-cvs] [0f769edafe7] blender-v2.93-release: VSE: Fix freeing display buffer cache before use

[Richard Antalik]

Commit: 0f769edafe7237f0f7edc7f53d5934f280c4c0a7
Author: Richard Antalik
Date:   Fri May 7 09:57:09 2021 +0200
Branches: blender-v2.93-release
https://developer.blender.org/rB0f769edafe7237f0f7edc7f53d5934f280c4c0a7

VSE: Fix freeing display buffer cache before use

`IMB_display_buffer_release()` was called before `display_buffer` was
used by drawing code. This should not be done as it may cause problems.

===================================================================

M	source/blender/editors/space_sequencer/sequencer_draw.c

===================================================================

diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index 7beb61e48d2..9c4aa5bf27d 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -1522,10 +1522,9 @@ static void *sequencer_OCIO_transform_ibuf(const bContext *C,
                                            ImBuf *ibuf,
                                            bool *r_glsl_used,
                                            eGPUTextureFormat *r_format,
-                                           eGPUDataFormat *r_data)
+                                           eGPUDataFormat *r_data, void **r_buffer_cache_handle)
 {
   void *display_buffer;
-  void *cache_handle = NULL;
   bool force_fallback = false;
   *r_glsl_used = false;
   force_fallback |= (ED_draw_imbuf_method(ibuf) != IMAGE_DRAW_METHOD_GLSL);
@@ -1578,13 +1577,10 @@ static void *sequencer_OCIO_transform_ibuf(const bContext *C,
   /* There is data to be displayed, but GLSL is not initialized
    * properly, in this case we fallback to CPU-based display transform. */
   if ((ibuf->rect || ibuf->rect_float) && !*r_glsl_used) {
-    display_buffer = IMB_display_buffer_acquire_ctx(C, ibuf, &cache_handle);
+    display_buffer = IMB_display_buffer_acquire_ctx(C, ibuf, r_buffer_cache_handle);
     *r_format = GPU_RGBA8;
     *r_data = GPU_DATA_UBYTE;
   }
-  if (cache_handle) {
-    IMB_display_buffer_release(cache_handle);
-  }
 
   return display_buffer;
 }
@@ -1658,6 +1654,7 @@ static void sequencer_draw_display_buffer(const bContext *C,
                                           bool draw_backdrop)
 {
   void *display_buffer;
+  void *buffer_cache_handle = NULL;
 
   if (sseq->mainb == SEQ_DRAW_IMG_IMBUF && sseq->flag & SEQ_USE_ALPHA) {
     GPU_blend(GPU_BLEND_ALPHA);
@@ -1685,7 +1682,7 @@ static void sequencer_draw_display_buffer(const bContext *C,
     data = GPU_DATA_UBYTE;
   }
   else {
-    display_buffer = sequencer_OCIO_transform_ibuf(C, ibuf, &glsl_used, &format, &data);
+    display_buffer = sequencer_OCIO_transform_ibuf(C, ibuf, &glsl_used, &format, &data, &buffer_cache_handle);
   }
 
   if (draw_backdrop) {
@@ -1745,6 +1742,10 @@ static void sequencer_draw_display_buffer(const bContext *C,
     IMB_colormanagement_finish_glsl_draw();
   }
 
+  if (buffer_cache_handle) {
+    IMB_display_buffer_release(buffer_cache_handle);
+  }
+
   if (sseq->mainb == SEQ_DRAW_IMG_IMBUF && sseq->flag & SEQ_USE_ALPHA) {
     GPU_blend(GPU_BLEND_NONE);
   }