Curves: Avoid duplication of control points during evaluation

This commit avoids duplicating the deformed control point
list twice by modifying the list in the object curve cache directly.

For curves, the original control point data was duplicated into a
local listbase, deformed, used to create the "bevel list" data, and
then duplicated again for the object-level storage of deformed
control points. Text objects and surface objects had a similar
unnecessary duplication.

1 files changed, 13 insertions, 18 deletions

diff --git a/source/blender/blenkernel/intern/displist.cc b/source/blender/blenkernel/intern/displist.cc
index 8821da29dde..7f4db0be34e 100644
--- a/source/blender/blenkernel/intern/displist.cc
+++ b/source/blender/blenkernel/intern/displist.cc
@@ -1100,20 +1100,21 @@ static void evaluate_surface_object(Depsgraph *depsgraph,
                                     Mesh **r_final)
 {
   BLI_assert(ob->type == OB_SURF);
-  ListBase nubase = {nullptr, nullptr};
   const Curve *cu = (const Curve *)ob->data;
 
+  ListBase *deformed_nurbs = &ob->runtime.curve_cache->deformed_nurbs;
+
   if (!for_render && cu->editnurb) {
-    BKE_nurbList_duplicate(&nubase, BKE_curve_editNurbs_get(const_cast<Curve *>(cu)));
+    BKE_nurbList_duplicate(deformed_nurbs, BKE_curve_editNurbs_get_for_read(cu));
   }
   else {
-    BKE_nurbList_duplicate(&nubase, &cu->nurb);
+    BKE_nurbList_duplicate(deformed_nurbs, &cu->nurb);
   }
 
   bool force_mesh_conversion = BKE_curve_calc_modifiers_pre(
-      depsgraph, scene, ob, &nubase, &nubase, for_render);
+      depsgraph, scene, ob, deformed_nurbs, deformed_nurbs, for_render);
 
-  LISTBASE_FOREACH (const Nurb *, nu, &nubase) {
+  LISTBASE_FOREACH (const Nurb *, nu, deformed_nurbs) {
     if (!(for_render || nu->hide == 0) || !BKE_nurb_check_valid_uv(nu)) {
       continue;
     }
@@ -1174,11 +1175,8 @@ static void evaluate_surface_object(Depsgraph *depsgraph,
     }
   }
 
-  BKE_nurbList_duplicate(&ob->runtime.curve_cache->deformed_nurbs, &nubase);
   curve_calc_modifiers_post(
       depsgraph, scene, ob, r_dispbase, for_render, force_mesh_conversion, r_final);
-
-  BKE_nurbList_free(&nubase);
 }
 
 static void rotateBevelPiece(const Curve *cu,
@@ -1408,19 +1406,19 @@ static void evaluate_curve_type_object(Depsgraph *depsgraph,
   BLI_assert(ELEM(ob->type, OB_CURVE, OB_FONT));
   const Curve *cu = (const Curve *)ob->data;
 
-  ListBase nubase = {nullptr, nullptr};
+  ListBase *deformed_nurbs = &ob->runtime.curve_cache->deformed_nurbs;
 
   if (ob->type == OB_FONT) {
-    BKE_vfont_to_curve_nubase(ob, FO_EDIT, &nubase);
+    BKE_vfont_to_curve_nubase(ob, FO_EDIT, deformed_nurbs);
   }
   else {
-    BKE_nurbList_duplicate(&nubase, BKE_curve_nurbs_get(const_cast<Curve *>(cu)));
+    BKE_nurbList_duplicate(deformed_nurbs, BKE_curve_nurbs_get_for_read(cu));
   }
 
   bool force_mesh_conversion = BKE_curve_calc_modifiers_pre(
-      depsgraph, scene, ob, &nubase, &nubase, for_render);
+      depsgraph, scene, ob, deformed_nurbs, deformed_nurbs, for_render);
 
-  BKE_curve_bevelList_make(ob, &nubase, for_render);
+  BKE_curve_bevelList_make(ob, deformed_nurbs, for_render);
 
   if ((cu->flag & CU_PATH) ||
       DEG_get_eval_flags_for_id(depsgraph, &ob->id) & DAG_EVAL_NEED_CURVE_PATH) {
@@ -1432,13 +1430,13 @@ static void evaluate_curve_type_object(Depsgraph *depsgraph,
 
   /* no bevel or extrude, and no width correction? */
   if (BLI_listbase_is_empty(&dlbev) && cu->width == 1.0f) {
-    curve_to_displist(cu, &nubase, for_render, r_dispbase);
+    curve_to_displist(cu, deformed_nurbs, for_render, r_dispbase);
   }
   else {
     const float widfac = cu->width - 1.0f;
 
     const BevList *bl = (BevList *)ob->runtime.curve_cache->bev.first;
-    const Nurb *nu = (Nurb *)nubase.first;
+    const Nurb *nu = (Nurb *)deformed_nurbs->first;
     for (; bl && nu; bl = bl->next, nu = nu->next) {
       float *data;
 
@@ -1611,15 +1609,12 @@ static void evaluate_curve_type_object(Depsgraph *depsgraph,
     curve_to_filledpoly(cu, r_dispbase);
   }
 
-  BKE_nurbList_duplicate(&ob->runtime.curve_cache->deformed_nurbs, &nubase);
   curve_calc_modifiers_post(
       depsgraph, scene, ob, r_dispbase, for_render, force_mesh_conversion, r_final);
 
   if (cu->flag & CU_DEFORM_FILL && !ob->runtime.data_eval) {
     curve_to_filledpoly(cu, r_dispbase);
   }
-
-  BKE_nurbList_free(&nubase);
 }
 
 void BKE_displist_make_curveTypes(Depsgraph *depsgraph,