Refactor: Move vertex group names to object data

This commit moves the storage of `bDeformGroup` and the active index
to `Mesh`, `Lattice`, and `bGPdata` instead of `Object`. Utility
functions are added to allow easy access to the vertex groups given
an object or an ID.

As explained in T88951, the list of vertex group names is currently
stored separately per object, even though vertex group data is stored
on the geometry. This tends to complicate code and cause bugs,
especially as geometry is created procedurally and tied less closely
to an object.

The "Copy Vertex Groups to Linked" operator is removed, since they
are stored on the geometry anyway.

This patch leaves the object-level python API for vertex groups in
place. Creating a geometry-level RNA API can be a separate step;
the changes in this commit are invasive enough as it is.

Note that opening a file saved in 3.0 in an earlier version means
the vertex groups will not be available.

Differential Revision: https://developer.blender.org/D11689

5 files changed, 30 insertions, 26 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_utils.c b/source/blender/editors/sculpt_paint/paint_utils.c
index 2484f382ed4..709e04d807d 100644
--- a/source/blender/editors/sculpt_paint/paint_utils.c
+++ b/source/blender/editors/sculpt_paint/paint_utils.c
@@ -752,7 +752,7 @@ static int vert_select_ungrouped_exec(bContext *C, wmOperator *op)
   Object *ob = CTX_data_active_object(C);
   Mesh *me = ob->data;
 
-  if (BLI_listbase_is_empty(&ob->defbase) || (me->dvert == NULL)) {
+  if (BLI_listbase_is_empty(&me->vertex_group_names) || (me->dvert == NULL)) {
     BKE_report(op->reports, RPT_ERROR, "No weights/vertex groups on object");
     return OPERATOR_CANCELLED;
   }
diff --git a/source/blender/editors/sculpt_paint/paint_vertex.c b/source/blender/editors/sculpt_paint/paint_vertex.c
index 5c1cc6cadcf..9387b84f437 100644
--- a/source/blender/editors/sculpt_paint/paint_vertex.c
+++ b/source/blender/editors/sculpt_paint/paint_vertex.c
@@ -1607,13 +1607,13 @@ static bool wpaint_stroke_test_start(bContext *C, wmOperator *op, const float mo
     /* check if we are attempting to paint onto a locked vertex group,
      * and other options disallow it from doing anything useful */
     bDeformGroup *dg;
-    dg = BLI_findlink(&ob->defbase, vgroup_index.active);
+    dg = BLI_findlink(&me->vertex_group_names, vgroup_index.active);
     if (dg->flag & DG_LOCK_WEIGHT) {
       BKE_report(op->reports, RPT_WARNING, "Active group is locked, aborting");
       return false;
     }
     if (vgroup_index.mirror != -1) {
-      dg = BLI_findlink(&ob->defbase, vgroup_index.mirror);
+      dg = BLI_findlink(&me->vertex_group_names, vgroup_index.mirror);
       if (dg->flag & DG_LOCK_WEIGHT) {
         BKE_report(op->reports, RPT_WARNING, "Mirror group is locked, aborting");
         return false;
@@ -1622,7 +1622,7 @@ static bool wpaint_stroke_test_start(bContext *C, wmOperator *op, const float mo
   }
 
   /* check that multipaint groups are unlocked */
-  defbase_tot = BLI_listbase_count(&ob->defbase);
+  defbase_tot = BLI_listbase_count(&me->vertex_group_names);
   defbase_sel = BKE_object_defgroup_selected_get(ob, defbase_tot, &defbase_tot_sel);
 
   if (ts->multipaint && defbase_tot_sel > 1) {
@@ -1636,7 +1636,7 @@ static bool wpaint_stroke_test_start(bContext *C, wmOperator *op, const float mo
 
     for (i = 0; i < defbase_tot; i++) {
       if (defbase_sel[i]) {
-        dg = BLI_findlink(&ob->defbase, i);
+        dg = BLI_findlink(&me->vertex_group_names, i);
         if (dg->flag & DG_LOCK_WEIGHT) {
           BKE_report(op->reports, RPT_WARNING, "Multipaint group is locked, aborting");
           MEM_freeN(defbase_sel);
@@ -2498,7 +2498,7 @@ static void wpaint_stroke_done(const bContext *C, struct PaintStroke *stroke)
 
     for (psys = ob->particlesystem.first; psys; psys = psys->next) {
       for (i = 0; i < PSYS_TOT_VG; i++) {
-        if (psys->vgroup[i] == ob->actdef) {
+        if (psys->vgroup[i] == BKE_object_defgroup_active_index_get(ob)) {
           psys->recalc |= ID_RECALC_PSYS_RESET;
           break;
         }
diff --git a/source/blender/editors/sculpt_paint/paint_vertex_color_ops.c b/source/blender/editors/sculpt_paint/paint_vertex_color_ops.c
index 96d22fe4a21..9f023dd6e63 100644
--- a/source/blender/editors/sculpt_paint/paint_vertex_color_ops.c
+++ b/source/blender/editors/sculpt_paint/paint_vertex_color_ops.c
@@ -149,7 +149,7 @@ static bool vertex_paint_from_weight(Object *ob)
   /* TODO: respect selection. */
   /* TODO: Do we want to take weights from evaluated mesh instead? 2.7x was not doing it anyway. */
   mp = me->mpoly;
-  vgroup_active = ob->actdef - 1;
+  vgroup_active = me->vertex_group_active_index - 1;
   for (int i = 0; i < me->totpoly; i++, mp++) {
     MLoopCol *lcol = &me->mloopcol[mp->loopstart];
     uint j = 0;
diff --git a/source/blender/editors/sculpt_paint/paint_vertex_weight_ops.c b/source/blender/editors/sculpt_paint/paint_vertex_weight_ops.c
index 5e047283534..cb8dc838422 100644
--- a/source/blender/editors/sculpt_paint/paint_vertex_weight_ops.c
+++ b/source/blender/editors/sculpt_paint/paint_vertex_weight_ops.c
@@ -183,7 +183,7 @@ static int weight_sample_invoke(bContext *C, wmOperator *op, const wmEvent *even
   ED_view3d_viewcontext_init(C, &vc, depsgraph);
   me = BKE_mesh_from_object(vc.obact);
 
-  if (me && me->dvert && vc.v3d && vc.rv3d && (vc.obact->actdef != 0)) {
+  if (me && me->dvert && vc.v3d && vc.rv3d && (me->vertex_group_active_index != 0)) {
     const bool use_vert_sel = (me->editflag & ME_EDIT_PAINT_VERT_SEL) != 0;
     int v_idx_best = -1;
     uint index;
@@ -213,9 +213,9 @@ static int weight_sample_invoke(bContext *C, wmOperator *op, const wmEvent *even
     if (v_idx_best != -1) { /* should always be valid */
       ToolSettings *ts = vc.scene->toolsettings;
       Brush *brush = BKE_paint_brush(&ts->wpaint->paint);
-      const int vgroup_active = vc.obact->actdef - 1;
+      const int vgroup_active = me->vertex_group_active_index - 1;
       float vgroup_weight = BKE_defvert_find_weight(&me->dvert[v_idx_best], vgroup_active);
-      const int defbase_tot = BLI_listbase_count(&vc.obact->defbase);
+      const int defbase_tot = BLI_listbase_count(&me->vertex_group_names);
       bool use_lock_relative = ts->wpaint_lock_relative;
       bool *defbase_locked = NULL, *defbase_unlocked = NULL;
 
@@ -331,8 +331,8 @@ static const EnumPropertyItem *weight_paint_sample_enum_itemf(bContext *C,
       ED_view3d_viewcontext_init(C, &vc, depsgraph);
       me = BKE_mesh_from_object(vc.obact);
 
-      if (me && me->dvert && vc.v3d && vc.rv3d && vc.obact->defbase.first) {
-        const int defbase_tot = BLI_listbase_count(&vc.obact->defbase);
+      if (me && me->dvert && vc.v3d && vc.rv3d && me->vertex_group_names.first) {
+        const int defbase_tot = BLI_listbase_count(&me->vertex_group_names);
         const bool use_vert_sel = (me->editflag & ME_EDIT_PAINT_VERT_SEL) != 0;
         int *groups = MEM_callocN(defbase_tot * sizeof(int), "groups");
         bool found = false;
@@ -372,7 +372,7 @@ static const EnumPropertyItem *weight_paint_sample_enum_itemf(bContext *C,
           int totitem = 0;
           int i = 0;
           bDeformGroup *dg;
-          for (dg = vc.obact->defbase.first; dg && i < defbase_tot; i++, dg = dg->next) {
+          for (dg = me->vertex_group_names.first; dg && i < defbase_tot; i++, dg = dg->next) {
             if (groups[i]) {
               item_tmp.identifier = item_tmp.name = dg->name;
               item_tmp.value = i;
@@ -401,7 +401,7 @@ static int weight_sample_group_exec(bContext *C, wmOperator *op)
   ED_view3d_viewcontext_init(C, &vc, depsgraph);
 
   BLI_assert(type + 1 >= 0);
-  vc.obact->actdef = type + 1;
+  BKE_object_defgroup_active_index_set(vc.obact, type + 1);
 
   DEG_id_tag_update(&vc.obact->id, ID_RECALC_GEOMETRY);
   WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, vc.obact);
@@ -458,7 +458,7 @@ static bool weight_paint_set(Object *ob, float paintweight)
     return false;
   }
 
-  vgroup_active = ob->actdef - 1;
+  vgroup_active = BKE_object_defgroup_active_index_get(ob) - 1;
 
   /* if mirror painting, find the other group */
   if (ME_USING_MIRROR_X_VERTEX_GROUPS(me)) {
@@ -815,7 +815,7 @@ static int paint_weight_gradient_exec(bContext *C, wmOperator *op)
   data.sco_start = sco_start;
   data.sco_end = sco_end;
   data.sco_line_div = 1.0f / len_v2v2(sco_start, sco_end);
-  data.def_nr = ob->actdef - 1;
+  data.def_nr = BKE_object_defgroup_active_index_get(ob) - 1;
   data.use_select = (me->editflag & (ME_EDIT_PAINT_FACE_SEL | ME_EDIT_PAINT_VERT_SEL)) != 0;
   data.vert_cache = vert_cache;
   data.vert_visit = NULL;
@@ -863,7 +863,7 @@ static int paint_weight_gradient_exec(bContext *C, wmOperator *op)
   }
 
   if (scene->toolsettings->auto_normalize) {
-    const int vgroup_num = BLI_listbase_count(&ob->defbase);
+    const int vgroup_num = BLI_listbase_count(&me->vertex_group_names);
     bool *vgroup_validmap = BKE_object_defgroup_validmap_get(ob, vgroup_num);
     if (vgroup_validmap != NULL) {
       MDeformVert *dvert = me->dvert;
diff --git a/source/blender/editors/sculpt_paint/paint_vertex_weight_utils.c b/source/blender/editors/sculpt_paint/paint_vertex_weight_utils.c
index d6a118bbd59..19ffa0c952d 100644
--- a/source/blender/editors/sculpt_paint/paint_vertex_weight_utils.c
+++ b/source/blender/editors/sculpt_paint/paint_vertex_weight_utils.c
@@ -79,8 +79,10 @@ bool ED_wpaint_ensure_data(bContext *C,
     WM_event_add_notifier(C, NC_GEOM | ND_DATA, me);
   }
 
+  const ListBase *defbase = BKE_object_defgroup_list(ob);
+
   /* this happens on a Bone select, when no vgroup existed yet */
-  if (ob->actdef <= 0) {
+  if (me->vertex_group_active_index <= 0) {
     Object *modob;
     if ((modob = BKE_modifiers_is_deformed_by_armature(ob))) {
       Bone *actbone = ((bArmature *)modob->data)->act_bone;
@@ -94,32 +96,33 @@ bool ED_wpaint_ensure_data(bContext *C,
             DEG_relations_tag_update(CTX_data_main(C));
           }
           else {
-            int actdef = 1 + BLI_findindex(&ob->defbase, dg);
+
+            int actdef = 1 + BLI_findindex(defbase, dg);
             BLI_assert(actdef >= 0);
-            ob->actdef = actdef;
+            me->vertex_group_active_index = actdef;
           }
         }
       }
     }
   }
-  if (BLI_listbase_is_empty(&ob->defbase)) {
+  if (BLI_listbase_is_empty(defbase)) {
     BKE_object_defgroup_add(ob);
     DEG_relations_tag_update(CTX_data_main(C));
   }
 
   /* ensure we don't try paint onto an invalid group */
-  if (ob->actdef <= 0) {
+  if (me->vertex_group_active_index <= 0) {
     BKE_report(reports, RPT_WARNING, "No active vertex group for painting, aborting");
     return false;
   }
 
   if (vgroup_index) {
-    vgroup_index->active = ob->actdef - 1;
+    vgroup_index->active = me->vertex_group_active_index - 1;
   }
 
   if (flag & WPAINT_ENSURE_MIRROR) {
     if (ME_USING_MIRROR_X_VERTEX_GROUPS(me)) {
-      int mirror = ED_wpaint_mirror_vgroup_ensure(ob, ob->actdef - 1);
+      int mirror = ED_wpaint_mirror_vgroup_ensure(ob, me->vertex_group_active_index - 1);
       if (vgroup_index) {
         vgroup_index->mirror = mirror;
       }
@@ -133,7 +136,8 @@ bool ED_wpaint_ensure_data(bContext *C,
 /* mirror_vgroup is set to -1 when invalid */
 int ED_wpaint_mirror_vgroup_ensure(Object *ob, const int vgroup_active)
 {
-  bDeformGroup *defgroup = BLI_findlink(&ob->defbase, vgroup_active);
+  const ListBase *defbase = BKE_object_defgroup_list(ob);
+  bDeformGroup *defgroup = BLI_findlink(defbase, vgroup_active);
 
   if (defgroup) {
     int mirrdef;
@@ -143,7 +147,7 @@ int ED_wpaint_mirror_vgroup_ensure(Object *ob, const int vgroup_active)
     mirrdef = BKE_object_defgroup_name_index(ob, name_flip);
     if (mirrdef == -1) {
       if (BKE_object_defgroup_new(ob, name_flip)) {
-        mirrdef = BLI_listbase_count(&ob->defbase) - 1;
+        mirrdef = BLI_listbase_count(defbase) - 1;
       }
     }