VSE: Image transform tools

Add tools for image manipulation in sequencer preview region.

This includes:
- Translate, rotate and resize operators, tools and gizmos
- Origin for image transformation
- Median point and individual origins pivot modes
- Select and Box select operator works in preview
- Image overlay drawing

ref T90156

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D12105

1 files changed, 9 insertions, 0 deletions

diff --git a/source/blender/sequencer/SEQ_transform.h b/source/blender/sequencer/SEQ_transform.h
index 1977835f627..328efb9424a 100644
--- a/source/blender/sequencer/SEQ_transform.h
+++ b/source/blender/sequencer/SEQ_transform.h
@@ -61,6 +61,15 @@ void SEQ_transform_offset_after_frame(struct Scene *scene,
                                       const int delta,
                                       const int timeline_frame);
 
+/* Image transformation. */
+void SEQ_image_transform_mirror_factor_get(const struct Sequence *seq, float r_mirror[2]);
+void SEQ_image_transform_origin_offset_pixelspace_get(const struct Scene *scene,
+                                                      const struct Sequence *seq,
+                                                      float r_origin[2]);
+void SEQ_image_transform_final_quad_get(const struct Scene *scene,
+                                        const struct Sequence *seq,
+                                        float r_quad[4][2]);
+
 #ifdef __cplusplus
 }
 #endif