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, 4 insertions, 7 deletions

diff --git a/source/blender/editors/include/ED_particle.h b/source/blender/editors/include/ED_particle.h
index 6cb8c0cfb19..fa5abb8e1dd 100644
--- a/source/blender/editors/include/ED_particle.h
+++ b/source/blender/editors/include/ED_particle.h
@@ -38,6 +38,7 @@ struct ParticleEditSettings;
 struct rcti;
 struct PTCacheEdit;
 struct Scene;
+struct UndoType;
 
 /* particle edit mode */
 void PE_free_ptcache_edit(struct PTCacheEdit *edit);
@@ -61,14 +62,10 @@ int PE_circle_select(struct bContext *C, int selecting, const int mval[2], float
 int PE_lasso_select(struct bContext *C, const int mcords[][2], const short moves, bool extend, bool select);
 void PE_deselect_all_visible(struct PTCacheEdit *edit);
 
-/* undo */
+/* particle_edit_undo.c */
+void ED_particle_undosys_type(struct UndoType *ut);
+
 void PE_undo_push(struct Scene *scene, const char *str);
-void PE_undo_step(struct Scene *scene, int step);
-void PE_undo(struct Scene *scene);
-void PE_redo(struct Scene *scene);
-bool PE_undo_is_valid(struct Scene *scene);
-void PE_undo_number(struct Scene *scene, int nr);
-const char *PE_undo_get_name(struct Scene *scene, int nr, bool *r_active);
 
 #endif /* __ED_PARTICLE_H__ */