Curve: Remove 'CU_2D' flag used for nurbs

This fixes T86440

As the CU_2D flag is set for nurbs, a Curve can have 2D nurbs mixed with 3D.

But the UI does not allow this mixing. It updates all nurbs to 2D or 3D when set.

So remove this specific flag for nurbs.

This may break old files, since 2D curves with mixed 3D are now set as 3D.

Differential Revision: https://developer.blender.org/D10738

19 files changed, 86 insertions, 84 deletions

diff --git a/source/blender/blenkernel/BKE_curve.h b/source/blender/blenkernel/BKE_curve.h
index 2380af6a08e..8381f015bee 100644
--- a/source/blender/blenkernel/BKE_curve.h
+++ b/source/blender/blenkernel/BKE_curve.h
@@ -69,16 +69,16 @@ typedef struct CVKeyIndex {
 #define SEGMENTSU(nu) (((nu)->flagu & CU_NURB_CYCLIC) ? (nu)->pntsu : (nu)->pntsu - 1)
 #define SEGMENTSV(nu) (((nu)->flagv & CU_NURB_CYCLIC) ? (nu)->pntsv : (nu)->pntsv - 1)
 
-#define CU_DO_TILT(cu, nu) ((((nu)->flag & CU_2D) && ((cu)->flag & CU_3D) == 0) ? 0 : 1)
 #define CU_DO_RADIUS(cu, nu) \
-  ((CU_DO_TILT(cu, nu) || ((cu)->flag & CU_PATH_RADIUS) || (cu)->bevobj || (cu)->ext1 != 0.0f || \
+  ((((cu)->flag & (CU_PATH_RADIUS | CU_3D)) || (cu)->bevobj || (cu)->ext1 != 0.0f || \
     (cu)->ext2 != 0.0f) ? \
        1 : \
        0)
 
+#define CU_IS_2D(cu) (((cu)->flag & CU_3D) == 0)
+
 /* not 3d and not unfilled */
-#define CU_DO_2DFILL(cu) \
-  ((((cu)->flag & CU_3D) == 0) && (((cu)->flag & (CU_FRONT | CU_BACK)) != 0))
+#define CU_DO_2DFILL(cu) (CU_IS_2D(cu) && (((cu)->flag & (CU_FRONT | CU_BACK)) != 0))
 
 /* ** Curve ** */
 void BKE_curve_editfont_free(struct Curve *cu);
@@ -86,7 +86,7 @@ void BKE_curve_init(struct Curve *cu, const short curve_type);
 struct Curve *BKE_curve_add(struct Main *bmain, const char *name, int type);
 short BKE_curve_type_get(const struct Curve *cu);
 void BKE_curve_type_test(struct Object *ob);
-void BKE_curve_curve_dimension_update(struct Curve *cu);
+void BKE_curve_dimension_update(struct Curve *cu);
 
 struct BoundBox *BKE_curve_boundbox_get(struct Object *ob);
 
@@ -186,7 +186,7 @@ void BKE_nurb_free(struct Nurb *nu);
 struct Nurb *BKE_nurb_duplicate(const struct Nurb *nu);
 struct Nurb *BKE_nurb_copy(struct Nurb *src, int pntsu, int pntsv);
 
-void BKE_nurb_test_2d(struct Nurb *nu);
+void BKE_nurb_project_2d(struct Nurb *nu);
 void BKE_nurb_minmax(const struct Nurb *nu, bool use_radius, float min[3], float max[3]);
 float BKE_nurb_calc_length(const struct Nurb *nu, int resolution);
 
diff --git a/source/blender/blenkernel/intern/curve.c b/source/blender/blenkernel/intern/curve.c
index 021aea20d22..95c242c31b2 100644
--- a/source/blender/blenkernel/intern/curve.c
+++ b/source/blender/blenkernel/intern/curve.c
@@ -462,24 +462,19 @@ short BKE_curve_type_get(const Curve *cu)
   return type;
 }
 
-void BKE_curve_curve_dimension_update(Curve *cu)
+void BKE_curve_dimension_update(Curve *cu)
 {
   ListBase *nurbs = BKE_curve_nurbs_get(cu);
+  bool is_2d = CU_IS_2D(cu);
 
-  if (cu->flag & CU_3D) {
-    LISTBASE_FOREACH (Nurb *, nu, nurbs) {
-      nu->flag &= ~CU_2D;
+  LISTBASE_FOREACH (Nurb *, nu, nurbs) {
+    if (is_2d) {
+      BKE_nurb_project_2d(nu);
     }
-  }
-  else {
-    LISTBASE_FOREACH (Nurb *, nu, nurbs) {
-      nu->flag |= CU_2D;
-      BKE_nurb_test_2d(nu);
 
-      /* since the handles are moved they need to be auto-located again */
-      if (nu->type == CU_BEZIER) {
-        BKE_nurb_handles_calc(nu);
-      }
+    /* since the handles are moved they need to be auto-located again */
+    if (nu->type == CU_BEZIER) {
+      BKE_nurb_handles_calc(nu);
     }
   }
 }
@@ -489,7 +484,10 @@ void BKE_curve_type_test(Object *ob)
   ob->type = BKE_curve_type_get(ob->data);
 
   if (ob->type == OB_CURVE) {
-    BKE_curve_curve_dimension_update((Curve *)ob->data);
+    Curve *cu = ob->data;
+    if (CU_IS_2D(cu)) {
+      BKE_curve_dimension_update(cu);
+    }
   }
 }
 
@@ -745,16 +743,12 @@ void BKE_nurbList_duplicate(ListBase *lb1, const ListBase *lb2)
   }
 }
 
-void BKE_nurb_test_2d(Nurb *nu)
+void BKE_nurb_project_2d(Nurb *nu)
 {
   BezTriple *bezt;
   BPoint *bp;
   int a;
 
-  if ((nu->flag & CU_2D) == 0) {
-    return;
-  }
-
   if (nu->type == CU_BEZIER) {
     a = nu->pntsu;
     bezt = nu->bezt;
@@ -2712,8 +2706,9 @@ void BKE_curve_bevelList_make(Object *ob, ListBase *nurbs, bool for_render)
       continue;
     }
 
-    /* check if we will calculate tilt data */
-    do_tilt = CU_DO_TILT(cu, nu);
+    /* Tilt, as the rotation angle of curve control points, is only calculated for 3D curves,
+     * (since this transformation affects the 3D space). */
+    do_tilt = (cu->flag & CU_3D) != 0;
 
     /* Normal display uses the radius, better just to calculate them. */
     do_radius = CU_DO_RADIUS(cu, nu);
@@ -3125,7 +3120,7 @@ void BKE_curve_bevelList_make(Object *ob, ListBase *nurbs, bool for_render)
     }
 
     /* turning direction */
-    if ((cu->flag & CU_3D) == 0) {
+    if (CU_IS_2D(cu)) {
       sd = sortdata;
       for (a = 0; a < poly; a++, sd++) {
         if (sd->bl->hole == sd->dir) {
@@ -3145,7 +3140,7 @@ void BKE_curve_bevelList_make(Object *ob, ListBase *nurbs, bool for_render)
   }
 
   /* STEP 4: 2D-COSINES or 3D ORIENTATION */
-  if ((cu->flag & CU_3D) == 0) {
+  if (CU_IS_2D(cu)) {
     /* 2D Curves */
     LISTBASE_FOREACH (BevList *, bl, bev) {
       if (bl->nr < 2) {
@@ -4730,9 +4725,7 @@ void BKE_curve_nurbs_vert_coords_apply_with_mat4(ListBase *lb,
     }
 
     if (constrain_2d) {
-      if (nu->flag & CU_2D) {
-        BKE_nurb_test_2d(nu);
-      }
+      BKE_nurb_project_2d(nu);
     }
 
     calchandlesNurb_intern(nu, SELECT, true);
@@ -4768,9 +4761,7 @@ void BKE_curve_nurbs_vert_coords_apply(ListBase *lb,
     }
 
     if (constrain_2d) {
-      if (nu->flag & CU_2D) {
-        BKE_nurb_test_2d(nu);
-      }
+      BKE_nurb_project_2d(nu);
     }
 
     calchandlesNurb_intern(nu, SELECT, true);
diff --git a/source/blender/blenkernel/intern/curve_convert.c b/source/blender/blenkernel/intern/curve_convert.c
index 988ddb3bbc0..5bcce9c339e 100644
--- a/source/blender/blenkernel/intern/curve_convert.c
+++ b/source/blender/blenkernel/intern/curve_convert.c
@@ -44,7 +44,7 @@ static Curve *curve_from_font_object(Object *object, Depsgraph *depsgraph)
   new_curve->type = OB_CURVE;
 
   new_curve->flag &= ~CU_3D;
-  BKE_curve_curve_dimension_update(new_curve);
+  BKE_curve_dimension_update(new_curve);
 
   return new_curve;
 }
diff --git a/source/blender/blenkernel/intern/displist.c b/source/blender/blenkernel/intern/displist.c
index a04bad45bf6..9022760fe34 100644
--- a/source/blender/blenkernel/intern/displist.c
+++ b/source/blender/blenkernel/intern/displist.c
@@ -1185,7 +1185,7 @@ void BKE_displist_make_surf(Depsgraph *depsgraph,
 
       /* dl->rt will be used as flag for render face and */
       /* CU_2D conflicts with R_NOPUNOFLIP */
-      dl->rt = nu->flag & ~CU_2D;
+      dl->rt = nu->flag;
 
       data = dl->verts;
       if (nu->flagu & CU_NURB_CYCLIC) {
@@ -1209,7 +1209,7 @@ void BKE_displist_make_surf(Depsgraph *depsgraph,
 
       /* dl->rt will be used as flag for render face and */
       /* CU_2D conflicts with R_NOPUNOFLIP */
-      dl->rt = nu->flag & ~CU_2D;
+      dl->rt = nu->flag;
 
       data = dl->verts;
       dl->type = DL_SURF;
@@ -1320,7 +1320,7 @@ static void fillBevelCap(const Nurb *nu,
 
   /* dl->rt will be used as flag for render face and */
   /* CU_2D conflicts with R_NOPUNOFLIP */
-  dl->rt = nu->flag & ~CU_2D;
+  dl->rt = nu->flag;
 
   BLI_addtail(dispbase, dl);
 }
@@ -1551,7 +1551,7 @@ static void do_makeDispListCurveTypes(Depsgraph *depsgraph,
 
           /* dl->rt will be used as flag for render face and */
           /* CU_2D conflicts with R_NOPUNOFLIP */
-          dl->rt = nu->flag & ~CU_2D;
+          dl->rt = nu->flag;
 
           int a = dl->nr;
           BevPoint *bevp = bl->bevpoints;
@@ -1606,7 +1606,7 @@ static void do_makeDispListCurveTypes(Depsgraph *depsgraph,
 
             /* dl->rt will be used as flag for render face and */
             /* CU_2D conflicts with R_NOPUNOFLIP */
-            dl->rt = nu->flag & ~CU_2D;
+            dl->rt = nu->flag;
 
             /* for each point of poly make a bevel piece */
             BevPoint *bevp_first = bl->bevpoints;
diff --git a/source/blender/blenkernel/intern/font.c b/source/blender/blenkernel/intern/font.c
index febc9e24c9f..64f44240eed 100644
--- a/source/blender/blenkernel/intern/font.c
+++ b/source/blender/blenkernel/intern/font.c
@@ -447,7 +447,6 @@ static void build_underline(Curve *cu,
   nu2->resolu = cu->resolu;
   nu2->bezt = NULL;
   nu2->knotsu = nu2->knotsv = NULL;
-  nu2->flag = CU_2D;
   nu2->charidx = charidx + 1000;
   if (mat_nr > 0) {
     nu2->mat_nr = mat_nr - 1;
diff --git a/source/blender/blenlib/intern/freetypefont.c b/source/blender/blenlib/intern/freetypefont.c
index e755a8e75b5..98da85e3a8c 100644
--- a/source/blender/blenlib/intern/freetypefont.c
+++ b/source/blender/blenlib/intern/freetypefont.c
@@ -135,7 +135,6 @@ static VChar *freetypechar_to_vchar(FT_Face face, FT_ULong charcode, VFontData *
       nu->type = CU_BEZIER;
       nu->pntsu = onpoints[j];
       nu->resolu = 8;
-      nu->flag = CU_2D;
       nu->flagu = CU_NURB_CYCLIC;
       nu->bezt = bezt;
 
diff --git a/source/blender/blenloader/intern/versioning_250.c b/source/blender/blenloader/intern/versioning_250.c
index 467fd8b0399..6338dc95aba 100644
--- a/source/blender/blenloader/intern/versioning_250.c
+++ b/source/blender/blenloader/intern/versioning_250.c
@@ -779,7 +779,6 @@ void blo_do_versions_250(FileData *fd, Library *lib, Main *bmain)
       Nurb *nu;
 
       for (nu = cu->nurb.first; nu; nu = nu->next) {
-        nu->flag |= (nu->type & CU_2D);
         nu->type &= CU_TYPE;
       }
     }
diff --git a/source/blender/blenloader/intern/versioning_290.c b/source/blender/blenloader/intern/versioning_290.c
index 4997639de5e..0d59845e934 100644
--- a/source/blender/blenloader/intern/versioning_290.c
+++ b/source/blender/blenloader/intern/versioning_290.c
@@ -57,6 +57,7 @@
 #include "BKE_collection.h"
 #include "BKE_colortools.h"
 #include "BKE_cryptomatte.h"
+#include "BKE_curve.h"
 #include "BKE_fcurve.h"
 #include "BKE_gpencil.h"
 #include "BKE_lib_id.h"
@@ -1983,5 +1984,25 @@ void blo_do_versions_290(FileData *fd, Library *UNUSED(lib), Main *bmain)
         }
       }
     }
+
+    /* The CU_2D flag has been removed. */
+    LISTBASE_FOREACH (Curve *, cu, &bmain->curves) {
+#define CU_2D (1 << 3)
+      ListBase *nurbs = BKE_curve_nurbs_get(cu);
+      bool is_2d = true;
+
+      LISTBASE_FOREACH (Nurb *, nu, nurbs) {
+        if (nu->flag & CU_2D) {
+          nu->flag &= ~CU_2D;
+        }
+        else {
+          is_2d = false;
+        }
+      }
+#undef CU_2D
+      if (!is_2d && CU_IS_2D(cu)) {
+        cu->flag |= CU_3D;
+      }
+    }
   }
 }
diff --git a/source/blender/editors/curve/curve_intern.h b/source/blender/editors/curve/curve_intern.h
index 704e4b740de..8ecf41162e9 100644
--- a/source/blender/editors/curve/curve_intern.h
+++ b/source/blender/editors/curve/curve_intern.h
@@ -142,7 +142,10 @@ struct GHash *ED_curve_keyindex_hash_duplicate(struct GHash *keyindex);
 void ED_curve_keyindex_update_nurb(struct EditNurb *editnurb, struct Nurb *nu, struct Nurb *newnu);
 
 /* helper functions */
-void ed_editnurb_translate_flag(struct ListBase *editnurb, uint8_t flag, const float vec[3]);
+void ed_editnurb_translate_flag(struct ListBase *editnurb,
+                                uint8_t flag,
+                                const float vec[3],
+                                bool is_2d);
 bool ed_editnurb_extrude_flag(struct EditNurb *editnurb, const uint8_t flag);
 bool ed_editnurb_spin(float viewmat[4][4],
                       struct View3D *v3d,
diff --git a/source/blender/editors/curve/editcurve.c b/source/blender/editors/curve/editcurve.c
index 4816a432376..767d822aa39 100644
--- a/source/blender/editors/curve/editcurve.c
+++ b/source/blender/editors/curve/editcurve.c
@@ -1314,7 +1314,6 @@ void ED_curve_editnurb_make(Object *obedit)
 
     LISTBASE_FOREACH (Nurb *, nu, &cu->nurb) {
       Nurb *newnu = BKE_nurb_duplicate(nu);
-      BKE_nurb_test_2d(newnu); /* after join, or any other creation of curve */
       BLI_addtail(&editnurb->nurbs, newnu);
     }
 
@@ -1706,7 +1705,7 @@ static void rotateflagNurb(ListBase *editnurb,
   }
 }
 
-void ed_editnurb_translate_flag(ListBase *editnurb, uint8_t flag, const float vec[3])
+void ed_editnurb_translate_flag(ListBase *editnurb, uint8_t flag, const float vec[3], bool is_2d)
 {
   /* all verts with ('flag' & flag) translate */
   BezTriple *bezt;
@@ -1741,7 +1740,9 @@ void ed_editnurb_translate_flag(ListBase *editnurb, uint8_t flag, const float ve
       }
     }
 
-    BKE_nurb_test_2d(nu);
+    if (is_2d) {
+      BKE_nurb_project_2d(nu);
+    }
   }
 }
 
@@ -5401,7 +5402,7 @@ static int ed_editcurve_addvert(Curve *cu,
     mul_v3_fl(center, 1.0f / (float)verts_len);
     sub_v3_v3v3(ofs, location_init, center);
 
-    if ((cu->flag & CU_3D) == 0) {
+    if (CU_IS_2D(cu)) {
       ofs[2] = 0.0f;
     }
 
@@ -5439,7 +5440,7 @@ static int ed_editcurve_addvert(Curve *cu,
 
     copy_v3_v3(location, location_init);
 
-    if ((cu->flag & CU_3D) == 0) {
+    if (CU_IS_2D(cu)) {
       location[2] = 0.0f;
     }
 
@@ -5455,10 +5456,6 @@ static int ed_editcurve_addvert(Curve *cu,
       nurb_new->orderu = 4;
       nurb_new->flag |= CU_SMOOTH;
       BKE_nurb_bezierPoints_add(nurb_new, 1);
-
-      if ((cu->flag & CU_3D) == 0) {
-        nurb_new->flag |= CU_2D;
-      }
     }
     else {
       /* Copy the active nurb settings. */
@@ -5590,7 +5587,7 @@ static int add_vertex_invoke(bContext *C, wmOperator *op, const wmEvent *event)
       ED_transform_snap_object_context_destroy(snap_context);
     }
 
-    if ((cu->flag & CU_3D) == 0) {
+    if (CU_IS_2D(cu)) {
       const float eps = 1e-6f;
 
       /* get the view vector to 'location' */
@@ -6922,9 +6919,9 @@ int ED_curve_join_objects_exec(bContext *C, wmOperator *op)
   cu = ob_active->data;
   BLI_movelisttolist(&cu->nurb, &tempbase);
 
-  if (ob_active->type == OB_CURVE) {
+  if (ob_active->type == OB_CURVE && CU_IS_2D(cu)) {
     /* Account for mixed 2D/3D curves when joining */
-    BKE_curve_curve_dimension_update(cu);
+    BKE_curve_dimension_update(cu);
   }
 
   DEG_relations_tag_update(bmain); /* because we removed object(s), call before editmode! */
diff --git a/source/blender/editors/curve/editcurve_add.c b/source/blender/editors/curve/editcurve_add.c
index 5b66d473466..065763764c1 100644
--- a/source/blender/editors/curve/editcurve_add.c
+++ b/source/blender/editors/curve/editcurve_add.c
@@ -380,10 +380,10 @@ Nurb *ED_curve_add_nurbs_primitive(
 
         mul_mat3_m4_v3(mat, vec);
 
-        ed_editnurb_translate_flag(editnurb, SELECT, vec);
+        ed_editnurb_translate_flag(editnurb, SELECT, vec, CU_IS_2D(cu));
         ed_editnurb_extrude_flag(cu->editnurb, SELECT);
         mul_v3_fl(vec, -2.0f);
-        ed_editnurb_translate_flag(editnurb, SELECT, vec);
+        ed_editnurb_translate_flag(editnurb, SELECT, vec, CU_IS_2D(cu));
 
         BLI_remlink(editnurb, nu);
 
@@ -492,15 +492,13 @@ Nurb *ED_curve_add_nurbs_primitive(
   BLI_assert(nu != NULL);
 
   if (nu) { /* should always be set */
-    if ((obedit->type != OB_SURF) && ((cu->flag & CU_3D) == 0)) {
-      nu->flag |= CU_2D;
-    }
-
     nu->flag |= CU_SMOOTH;
     cu->actnu = BLI_listbase_count(editnurb);
     cu->actvert = CU_ACT_NONE;
 
-    BKE_nurb_test_2d(nu);
+    if (CU_IS_2D(cu)) {
+      BKE_nurb_project_2d(nu);
+    }
   }
 
   return nu;
diff --git a/source/blender/editors/curve/editcurve_paint.c b/source/blender/editors/curve/editcurve_paint.c
index 0d071f2e595..6342076df34 100644
--- a/source/blender/editors/curve/editcurve_paint.c
+++ b/source/blender/editors/curve/editcurve_paint.c
@@ -1072,7 +1072,7 @@ static int curve_draw_invoke(bContext *C, wmOperator *op, const wmEvent *event)
     const float *plane_no = NULL;
     const float *plane_co = NULL;
 
-    if ((cu->flag & CU_3D) == 0) {
+    if (CU_IS_2D(cu)) {
       /* 2D overrides other options */
       plane_co = obedit->obmat[3];
       plane_no = obedit->obmat[2];
diff --git a/source/blender/editors/object/object_add.c b/source/blender/editors/object/object_add.c
index 7f189abe870..ef23197bc21 100644
--- a/source/blender/editors/object/object_add.c
+++ b/source/blender/editors/object/object_add.c
@@ -2897,7 +2897,7 @@ static int object_convert_exec(bContext *C, wmOperator *op)
       }
 
       cu->flag &= ~CU_3D;
-      BKE_curve_curve_dimension_update(cu);
+      BKE_curve_dimension_update(cu);
 
       if (target == OB_MESH) {
         /* No assumption should be made that the resulting objects is a mesh, as conversion can
diff --git a/source/blender/editors/object/object_data_transform.c b/source/blender/editors/object/object_data_transform.c
index 72dde7b734b..6e3a5e715f6 100644
--- a/source/blender/editors/object/object_data_transform.c
+++ b/source/blender/editors/object/object_data_transform.c
@@ -593,13 +593,14 @@ void ED_object_data_xform_by_mat4(struct XFormObjectData *xod_base, const float
       if (xod_base->is_edit_mode) {
         EditNurb *editnurb = cu->editnurb;
         nurb = &editnurb->nurbs;
-        BKE_curve_nurbs_vert_coords_apply_with_mat4(&editnurb->nurbs, xod->elem_array, mat, true);
+        BKE_curve_nurbs_vert_coords_apply_with_mat4(
+            &editnurb->nurbs, xod->elem_array, mat, CU_IS_2D(cu));
         /* Always operate on all keys for the moment. */
         // key_index = editnurb->shapenr - 1;
       }
       else {
         nurb = &cu->nurb;
-        BKE_curve_nurbs_vert_coords_apply_with_mat4(&cu->nurb, xod->elem_array, mat, true);
+        BKE_curve_nurbs_vert_coords_apply_with_mat4(&cu->nurb, xod->elem_array, mat, CU_IS_2D(cu));
       }
 
       if ((key != NULL) && (xod->key_data != NULL)) {
@@ -694,12 +695,12 @@ void ED_object_data_xform_restore(struct XFormObjectData *xod_base)
       struct XFormObjectData_Curve *xod = (struct XFormObjectData_Curve *)xod_base;
       if (xod_base->is_edit_mode) {
         EditNurb *editnurb = cu->editnurb;
-        BKE_curve_nurbs_vert_coords_apply(&editnurb->nurbs, xod->elem_array, true);
+        BKE_curve_nurbs_vert_coords_apply(&editnurb->nurbs, xod->elem_array, CU_IS_2D(cu));
         /* Always operate on all keys for the moment. */
         // key_index = editnurb->shapenr - 1;
       }
       else {
-        BKE_curve_nurbs_vert_coords_apply(&cu->nurb, xod->elem_array, true);
+        BKE_curve_nurbs_vert_coords_apply(&cu->nurb, xod->elem_array, CU_IS_2D(cu));
       }
 
       if ((key != NULL) && (xod->key_data != NULL)) {
diff --git a/source/blender/editors/space_view3d/view3d_buttons.c b/source/blender/editors/space_view3d/view3d_buttons.c
index 17f60dfc210..e42f6b5faac 100644
--- a/source/blender/editors/space_view3d/view3d_buttons.c
+++ b/source/blender/editors/space_view3d/view3d_buttons.c
@@ -1031,7 +1031,9 @@ static void v3d_editvertex_buts(uiLayout *layout, View3D *v3d, Object *ob, float
             }
           }
         }
-        BKE_nurb_test_2d(nu);
+        if (CU_IS_2D(cu)) {
+          BKE_nurb_project_2d(nu);
+        }
         BKE_nurb_handles_test(nu, true, false); /* test for bezier too */
       }
     }
diff --git a/source/blender/editors/transform/transform_convert_curve.c b/source/blender/editors/transform/transform_convert_curve.c
index bef3eca0d9d..3ff83e00f43 100644
--- a/source/blender/editors/transform/transform_convert_curve.c
+++ b/source/blender/editors/transform/transform_convert_curve.c
@@ -461,11 +461,7 @@ void recalcData_curve(TransInfo *t)
     }
     else {
       /* Normal updating */
-      while (nu) {
-        BKE_nurb_test_2d(nu);
-        BKE_nurb_handles_calc(nu);
-        nu = nu->next;
-      }
+      BKE_curve_dimension_update(cu);
     }
   }
 }
diff --git a/source/blender/editors/util/ed_transverts.c b/source/blender/editors/util/ed_transverts.c
index d0234dee856..ad45686dc75 100644
--- a/source/blender/editors/util/ed_transverts.c
+++ b/source/blender/editors/util/ed_transverts.c
@@ -111,7 +111,9 @@ void ED_transverts_update_obedit(TransVertStore *tvs, Object *obedit)
         }
       }
 
-      BKE_nurb_test_2d(nu);
+      if (CU_IS_2D(cu)) {
+        BKE_nurb_project_2d(nu);
+      }
       BKE_nurb_handles_test(nu, true, false); /* test for bezier too */
       nu = nu->next;
     }
diff --git a/source/blender/makesdna/DNA_curve_types.h b/source/blender/makesdna/DNA_curve_types.h
index ff2e7fc500a..02a1a713d02 100644
--- a/source/blender/makesdna/DNA_curve_types.h
+++ b/source/blender/makesdna/DNA_curve_types.h
@@ -425,7 +425,6 @@ enum {
 /* Nurb.flag */
 enum {
   CU_SMOOTH = 1 << 0,
-  CU_2D = 1 << 3, /* moved from type since 2.4x */
 };
 
 /* Nurb.type */
diff --git a/source/blender/makesrna/intern/rna_curve.c b/source/blender/makesrna/intern/rna_curve.c
index 3e90b4bd9d4..e670b17b79a 100644
--- a/source/blender/makesrna/intern/rna_curve.c
+++ b/source/blender/makesrna/intern/rna_curve.c
@@ -357,9 +357,8 @@ static void rna_Curve_dimension_set(PointerRNA *ptr, int value)
   }
   else {
     cu->flag &= ~CU_3D;
+    BKE_curve_dimension_update(cu);
   }
-
-  BKE_curve_curve_dimension_update(cu);
 }
 
 static const EnumPropertyItem *rna_Curve_fill_mode_itemf(bContext *UNUSED(C),
@@ -721,10 +720,6 @@ static Nurb *rna_Curve_spline_new(Curve *cu, int type)
   nu->resolv = cu->resolv;
   nu->flag = CU_SMOOTH;
 
-  if ((cu->flag & CU_3D) == 0) {
-    nu->flag |= CU_2D;
-  }
-
   BLI_addtail(BKE_curve_nurbs_get(cu), nu);
 
   return nu;