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

11 files changed, 56 insertions, 49 deletions

diff --git a/source/blender/editors/include/ED_armature.h b/source/blender/editors/include/ED_armature.h
index 91c9a36c31f..241bcbea4af 100644
--- a/source/blender/editors/include/ED_armature.h
+++ b/source/blender/editors/include/ED_armature.h
@@ -49,6 +49,7 @@ struct Scene;
 struct ViewContext;
 struct wmKeyConfig;
 struct wmOperator;
+struct UndoType;
 
 typedef struct EditBone {
 	struct EditBone *next, *prev;
@@ -139,7 +140,7 @@ bool ED_armature_select_pick(struct bContext *C, const int mval[2], bool extend,
 int join_armature_exec(struct bContext *C, struct wmOperator *op);
 struct Bone *get_indexed_bone(struct Object *ob, int index);
 float ED_rollBoneToVector(EditBone *bone, const float new_up_axis[3], const bool axis_only);
-EditBone *ED_armature_bone_find_name(const ListBase *edbo, const char *name);
+EditBone *ED_armature_bone_find_name(const struct ListBase *edbo, const char *name);
 EditBone *ED_armature_bone_get_mirrored(const struct ListBase *edbo, EditBone *ebo);
 void ED_armature_sync_selection(struct ListBase *edbo);
 void ED_armature_validate_active(struct bArmature *arm);
@@ -178,8 +179,6 @@ void unique_editbone_name(struct ListBase *ebones, char *name, EditBone *bone);
 void ED_armature_bone_rename(struct bArmature *arm, const char *oldnamep, const char *newnamep);
 void ED_armature_bones_flip_names(struct bArmature *arm, struct ListBase *bones_names, const bool do_strip_numbers);
 
-void undo_push_armature(struct bContext *C, const char *name);
-
 /* low level selection functions which handle */
 int  ED_armature_ebone_selectflag_get(const EditBone *ebone);
 void ED_armature_ebone_selectflag_set(EditBone *ebone, int flag);
@@ -187,6 +186,9 @@ void ED_armature_ebone_select_set(EditBone *ebone, bool select);
 void ED_armature_ebone_selectflag_enable(EditBone *ebone, int flag);
 void ED_armature_ebone_selectflag_disable(EditBone *ebone, int flag);
 
+/* editarmature_undo.c */
+void ED_armature_undosys_type(struct UndoType *ut);
+
 /* armature_utils.c */
 void ED_armature_ebone_listbase_temp_clear(struct ListBase *lb);
 void ED_armature_ebone_listbase_free(struct ListBase *lb);
diff --git a/source/blender/editors/include/ED_curve.h b/source/blender/editors/include/ED_curve.h
index d45e52d4c5a..da726cb8000 100644
--- a/source/blender/editors/include/ED_curve.h
+++ b/source/blender/editors/include/ED_curve.h
@@ -41,6 +41,7 @@ struct Curve;
 struct EditNurb;
 struct BezTriple;
 struct BPoint;
+struct UndoType;
 
 /* curve_ops.c */
 void    ED_operatortypes_curve(void);
@@ -48,7 +49,7 @@ void    ED_operatormacros_curve(void);
 void    ED_keymap_curve(struct wmKeyConfig *keyconf);
 
 /* editcurve.c */
-ListBase *object_editcurve_get(struct Object *ob);
+struct ListBase *object_editcurve_get(struct Object *ob);
 
 void    ED_curve_editnurb_load(struct Object *obedit);
 void    ED_curve_editnurb_make(struct Object *obedit);
@@ -72,7 +73,7 @@ void ED_curve_select_all(struct EditNurb *editnurb);
 void ED_curve_select_swap(struct EditNurb *editnurb, bool hide_handles);
 
 /* editcurve_undo.c */
-void undo_push_curve(struct bContext *C, const char *name);
+void ED_curve_undosys_type(struct UndoType *ut);
 
 /* editfont.c */
 void    ED_curve_editfont_load(struct Object *obedit);
@@ -91,7 +92,8 @@ bool ED_curve_active_center(struct Curve *cu, float center[3]);
 bool ED_curve_editfont_select_pick(struct bContext *C, const int mval[2], bool extend, bool deselect, bool toggle);
 
 /* editfont_undo.c */
-void    undo_push_font(struct bContext *C, const char *name);
+void ED_font_undosys_type(struct UndoType *ut);
+
 
 #if 0
 /* debug only */
diff --git a/source/blender/editors/include/ED_lattice.h b/source/blender/editors/include/ED_lattice.h
index b652fb4c00b..b30929f5307 100644
--- a/source/blender/editors/include/ED_lattice.h
+++ b/source/blender/editors/include/ED_lattice.h
@@ -31,6 +31,8 @@
 #define __ED_LATTICE_H__
 
 struct wmKeyConfig;
+struct UndoType;
+struct Object;
 
 /* lattice_ops.c */
 void ED_operatortypes_lattice(void);
@@ -41,6 +43,6 @@ void ED_lattice_flags_set(struct Object *obedit, int flag);
 bool ED_lattice_select_pick(struct bContext *C, const int mval[2], bool extend, bool deselect, bool toggle);
 
 /* editlattice_undo.c */
-void undo_push_lattice(struct bContext *C, const char *name);
+void ED_lattice_undosys_type(struct UndoType *ut);
 
 #endif  /* __ED_LATTICE_H__ */
diff --git a/source/blender/editors/include/ED_mball.h b/source/blender/editors/include/ED_mball.h
index 232d7d1d234..9982c87a764 100644
--- a/source/blender/editors/include/ED_mball.h
+++ b/source/blender/editors/include/ED_mball.h
@@ -34,6 +34,7 @@
 struct bContext;
 struct Object;
 struct wmKeyConfig;
+struct UndoType;
 
 void ED_operatortypes_metaball(void);
 void ED_operatormacros_metaball(void);
@@ -47,6 +48,7 @@ void ED_mball_editmball_free(struct Object *obedit);
 void ED_mball_editmball_make(struct Object *obedit);
 void ED_mball_editmball_load(struct Object *obedit);
 
-void undo_push_mball(struct bContext *C, const char *name);
+/* editmball_undo.c */
+void ED_mball_undosys_type(struct UndoType *ut);
 
 #endif  /* __ED_MBALL_H__ */
diff --git a/source/blender/editors/include/ED_mesh.h b/source/blender/editors/include/ED_mesh.h
index 40d796aeed1..349a1944a23 100644
--- a/source/blender/editors/include/ED_mesh.h
+++ b/source/blender/editors/include/ED_mesh.h
@@ -62,6 +62,7 @@ struct UvMapVert;
 struct ToolSettings;
 struct Object;
 struct rcti;
+struct UndoType;
 
 /* editmesh_utils.c */
 void           EDBM_verts_mirror_cache_begin_ex(struct BMEditMesh *em, const int axis,
@@ -98,8 +99,6 @@ void EDBM_selectmode_flush(struct BMEditMesh *em);
 void EDBM_deselect_flush(struct BMEditMesh *em);
 void EDBM_select_flush(struct BMEditMesh *em);
 
-void undo_push_mesh(struct bContext *C, const char *name);
-
 bool EDBM_vert_color_check(struct BMEditMesh *em);
 
 void EDBM_mesh_hide(struct BMEditMesh *em, bool swap);
@@ -130,6 +129,9 @@ void EDBM_flag_disable_all(struct BMEditMesh *em, const char hflag);
 bool BMBVH_EdgeVisible(struct BMBVHTree *tree, struct BMEdge *e,
                        struct ARegion *ar, struct View3D *v3d, struct Object *obedit);
 
+/* editmesh_undo.c */
+void ED_mesh_undosys_type(struct UndoType *ut);
+
 /* editmesh_select.c */
 void EDBM_select_mirrored(
         struct BMEditMesh *em, const int axis, const bool extend,
diff --git a/source/blender/editors/include/ED_object.h b/source/blender/editors/include/ED_object.h
index 5b2fdf29dd5..7faf975ea91 100644
--- a/source/blender/editors/include/ED_object.h
+++ b/source/blender/editors/include/ED_object.h
@@ -196,6 +196,7 @@ void ED_object_constraint_dependency_tag_update(struct Main *bmain, struct Objec
 bool ED_object_mode_compat_test(const struct Object *ob, eObjectMode mode);
 bool ED_object_mode_compat_set(struct bContext *C, struct Object *ob, eObjectMode mode, struct ReportList *reports);
 void ED_object_mode_toggle(struct bContext *C, eObjectMode mode);
+void ED_object_mode_set(struct bContext *C, eObjectMode mode);
 
 /* object_modifier.c */
 enum {
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__ */
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__ */
 
diff --git a/source/blender/editors/include/ED_sculpt.h b/source/blender/editors/include/ED_sculpt.h
index 6daaac5bb42..7c17e7b68c3 100644
--- a/source/blender/editors/include/ED_sculpt.h
+++ b/source/blender/editors/include/ED_sculpt.h
@@ -36,6 +36,9 @@ struct Object;
 struct RegionView3D;
 struct ViewContext;
 struct rcti;
+struct UndoStep;
+struct UndoType;
+struct ListBase;
 
 /* sculpt.c */
 void ED_operatortypes_sculpt(void);
@@ -43,4 +46,7 @@ void ED_sculpt_redraw_planes_get(float planes[4][4], struct ARegion *ar,
                                  struct RegionView3D *rv3d, struct Object *ob);
 int  ED_sculpt_mask_box_select(struct bContext *C, struct ViewContext *vc, const struct rcti *rect, bool select, bool extend);
 
+/* sculpt_undo.c */
+void ED_sculpt_undosys_type(struct UndoType *ut);
+
 #endif /* __ED_SCULPT_H__ */
diff --git a/source/blender/editors/include/ED_text.h b/source/blender/editors/include/ED_text.h
index 5df7d9cfaef..5517e50aef4 100644
--- a/source/blender/editors/include/ED_text.h
+++ b/source/blender/editors/include/ED_text.h
@@ -30,12 +30,13 @@
 #ifndef __ED_TEXT_H__
 #define __ED_TEXT_H__
 
-struct bContext;
 struct SpaceText;
 struct ARegion;
+struct UndoType;
 
-void ED_text_undo_step(struct bContext *C, int step);
 bool ED_text_region_location_from_cursor(struct SpaceText *st, struct ARegion *ar, const int cursor_co[2], int r_pixel_co[2]);
 
-#endif /* __ED_TEXT_H__ */
+/* text_undo.c */
+void ED_text_undosys_type(struct UndoType *ut);
 
+#endif /* __ED_TEXT_H__ */
diff --git a/source/blender/editors/include/ED_util.h b/source/blender/editors/include/ED_util.h
index 60c4b3593aa..5a373cebac1 100644
--- a/source/blender/editors/include/ED_util.h
+++ b/source/blender/editors/include/ED_util.h
@@ -35,6 +35,9 @@ struct bContext;
 struct SpaceLink;
 struct wmOperator;
 struct wmOperatorType;
+struct UndoStack;
+struct ScrArea;
+struct PackedFile;
 
 /* ed_util.c */
 
@@ -70,16 +73,12 @@ void    ED_undo_operator_repeat_cb_evt(struct bContext *C, void *arg_op, int arg
 
 bool    ED_undo_is_valid(const struct bContext *C, const char *undoname);
 
-/* undo_editmode.c */
-void undo_editmode_push(struct bContext *C, const char *name, 
-                        void * (*getdata)(struct bContext *C),
-                        void (*freedata)(void *),
-                        void (*to_editmode)(void *, void *, void *),
-                        void *(*from_editmode)(void *, void *),
-                        int (*validate_undo)(void *, void *));
+/* undo_system_types.c */
+void ED_undosys_type_init(void);
+void ED_undosys_type_free(void);
 
-
-void    undo_editmode_clear(void);
+/* memfile_undo.c */
+struct MemFile *ED_undosys_stack_memfile_get_active(struct UndoStack *ustack);
 
 /* ************** XXX OLD CRUFT WARNING ************* */