Sequencer: Transform ImBuf Processor.

Inside the sequencer the cropping and transform of images/buffers were
implemented locally. This reduced the optimizations that a compiler
could do and added confusing code styles. This patch adds
`IMB_transform` to reduce the confusion and increases compiler
optimizations as more code can be inlined and we can keep track of
indices inside the inner loop.

This increases end-user performance by 30% when playing back aa video
in VSE.

Reviewed By: ISS, zeddb

Differential Revision: https://developer.blender.org/D11549

1 files changed, 12 insertions, 0 deletions

diff --git a/source/blender/imbuf/IMB_imbuf.h b/source/blender/imbuf/IMB_imbuf.h
index 9c84127105a..651c69726ff 100644
--- a/source/blender/imbuf/IMB_imbuf.h
+++ b/source/blender/imbuf/IMB_imbuf.h
@@ -70,6 +70,7 @@ extern "C" {
  */
 struct ImBuf;
 struct rcti;
+struct rctf;
 
 /**
  *
@@ -323,6 +324,11 @@ typedef enum IMB_Proxy_Size {
   IMB_PROXY_MAX_SLOT = 4,
 } IMB_Proxy_Size;
 
+typedef enum eIMBInterpolationFilterMode {
+  IMB_FILTER_NEAREST,
+  IMB_FILTER_BILINEAR,
+} eIMBInterpolationFilterMode;
+
 /* Defaults to BL_proxy within the directory of the animation. */
 void IMB_anim_set_index_dir(struct anim *anim, const char *dir);
 void IMB_anim_get_fname(struct anim *anim, char *file, int size);
@@ -732,6 +738,12 @@ void IMB_processor_apply_threaded_scanlines(int total_scanlines,
                                             ScanlineThreadFunc do_thread,
                                             void *custom_data);
 
+void IMB_transform(struct ImBuf *src,
+                   struct ImBuf *dst,
+                   float transform_matrix[3][3],
+                   struct rctf *src_crop,
+                   const eIMBInterpolationFilterMode filter);
+
 /* ffmpeg */
 void IMB_ffmpeg_init(void);
 const char *IMB_ffmpeg_last_error(void);