Undo: unified undo system w/ linear history

- Use a single undo history for all operations.
- UndoType's are registered and poll the context to check if they
  should be used when performing an undo push.
- Mode switching is used to ensure the state is correct before
  undo data is restored.
- Some undo types accumulate changes (image & text editing)
  others store the state multiple times (with de-duplication).
  This is supported by checking UndoStack.mode `ACCUMULATE` / `STORE`.
- Each undo step stores ID datablocks they use with utilities to help
  manage restoring correct ID's.
  Needed since global undo is now mixed with other modes undo.
- Currently performs each undo step when going up/down history
  Previously this wasn't done, making history fail in some cases.
  This can be optimized to skip some combinations of undo steps.

grease-pencil is an exception which has not been updated
since it integrates undo into the draw-session.

See D3113

1 files changed, 13 insertions, 20 deletions

diff --git a/source/blender/editors/include/ED_paint.h b/source/blender/editors/include/ED_paint.h
index 79aa0a3a5ed..246419d64aa 100644
--- a/source/blender/editors/include/ED_paint.h
+++ b/source/blender/editors/include/ED_paint.h
@@ -28,31 +28,16 @@
 struct bContext;
 struct wmKeyConfig;
 struct wmOperator;
+struct ImBuf;
+struct Image;
+struct UndoStep;
+struct UndoType;
 
 /* paint_ops.c */
 void ED_operatortypes_paint(void);
 void ED_operatormacros_paint(void);
 void ED_keymap_paint(struct wmKeyConfig *keyconf);
 
-/* paint_undo.c */
-enum {
-	UNDO_PAINT_IMAGE    = 0,
-	UNDO_PAINT_MESH     = 1,
-};
-
-typedef void (*UndoRestoreCb)(struct bContext *C, struct ListBase *lb);
-typedef void (*UndoFreeCb)(struct ListBase *lb);
-typedef bool (*UndoCleanupCb)(struct bContext *C, struct ListBase *lb);
-
-int ED_undo_paint_step(struct bContext *C, int type, int step, const char *name);
-void ED_undo_paint_step_num(struct bContext *C, int type, int num);
-const char *ED_undo_paint_get_name(struct bContext *C, int type, int nr, bool *r_active);
-void ED_undo_paint_free(void);
-bool ED_undo_paint_is_valid(int type, const char *name);
-bool ED_undo_paint_empty(int type);
-void ED_undo_paint_push_begin(int type, const char *name, UndoRestoreCb restore, UndoFreeCb free, UndoCleanupCb cleanup);
-void ED_undo_paint_push_end(int type);
-
 /* paint_image.c */
 void ED_imapaint_clear_partial_redraw(void);
 void ED_imapaint_dirty_region(struct Image *ima, struct ImBuf *ibuf, int x, int y, int w, int h, bool find_old);
@@ -61,6 +46,14 @@ void ED_imapaint_bucket_fill(struct bContext *C, float color[3], struct wmOperat
 /* paint_image_undo.c */
 void ED_image_undo_push_begin(const char *name);
 void ED_image_undo_push_end(void);
-void ED_image_undo_restore(void);
+void ED_image_undo_restore(struct UndoStep *us);
+
+void ED_image_undosys_type(struct UndoType *ut);
+
+/* paint_curve_undo.c */
+void ED_paintcurve_undo_push_begin(const char *name);
+void ED_paintcurve_undo_push_end(void);
+
+void ED_paintcurve_undosys_type(struct UndoType *ut);
 
 #endif /* __ED_PAINT_H__ */