source/blender/editors/curves/intern/curves_data.cc

@@ -3,7 +3,36 @@
 #include "BKE_curves.hh"
 #include "BKE_geometry_fields.hh"
 
+#include "BLI_task.hh"
+
+#include "DNA_object_types.h"
+
 #include "ED_curves.h"
+#include "ED_transverts.h"
+
+namespace blender::ed::curves {
+
+void transverts_from_curves_positions_create(bke::CurvesGeometry &curves, TransVertStore *tvs)
+{
+  Vector<int64_t> selected_indices;
+  IndexMask selection = retrieve_selected_points(curves, selected_indices);
+  MutableSpan<float3> positions = curves.positions_for_write();
+
+  tvs->transverts = static_cast<TransVert *>(
+      MEM_calloc_arrayN(selection.size(), sizeof(TransVert), __func__));
+  tvs->transverts_tot = selection.size();
+
+  threading::parallel_for(selection.index_range(), 1024, [&](const IndexRange selection_range) {
+    for (const int point_i : selection_range) {
+      TransVert &tv = tvs->transverts[point_i];
+      tv.loc = positions[selection[point_i]];
+      tv.flag = SELECT;
+      copy_v3_v3(tv.oldloc, tv.loc);
+    }
+  });
+}
+
+}  // namespace blender::ed::curves
 
 float (*ED_curves_point_normals_array_create(const Curves *curves_id))[3]
 {
@@ -21,3 +50,10 @@ float (*ED_curves_point_normals_array_create(const Curves *curves_id))[3]
 
   return reinterpret_cast<float(*)[3]>(data);
 }
+
+void ED_curves_transverts_create(Curves *curves_id, TransVertStore *tvs)
+{
+  using namespace blender;
+  bke::CurvesGeometry &curves = curves_id->geometry.wrap();
+  ed::curves::transverts_from_curves_positions_create(curves, tvs);
+}

source/blender/editors/include/ED_curves.h

@@ -12,6 +12,7 @@ struct UndoType;
 struct SelectPick_Params;
 struct ViewContext;
 struct rcti;
+struct TransVertStore;
 
 #ifdef __cplusplus
 extern "C" {
@@ -32,6 +33,11 @@ void ED_keymap_curves(struct wmKeyConfig *keyconf);
  */
 float (*ED_curves_point_normals_array_create(const struct Curves *curves_id))[3];
 
+/**
+ * Wrapper for `transverts_from_curves_positions_create`.
+ */
+void ED_curves_transverts_create(struct Curves *curves_id, struct TransVertStore *tvs);
+
 /** \} */
 
 #ifdef __cplusplus
@@ -56,6 +62,13 @@ bke::CurvesGeometry primitive_random_sphere(int curves_size, int points_per_curv
 VectorSet<Curves *> get_unique_editable_curves(const bContext &C);
 void ensure_surface_deformation_node_exists(bContext &C, Object &curves_ob);
 
+/**
+ * Allocate an array of `TransVert` for cursor/selection snapping (See
+ * `ED_transverts_create_from_obedit` in `view3d_snap.c`).
+ * \note: the `TransVert` elements in \a tvs are expected to write to the positions of \a curves.
+ */
+void transverts_from_curves_positions_create(bke::CurvesGeometry &curves, TransVertStore *tvs);
+
 /* -------------------------------------------------------------------- */
 /** \name Poll Functions
  * \{ */

source/blender/editors/util/ed_transverts.c

@@ -9,6 +9,7 @@
 
 #include "DNA_armature_types.h"
 #include "DNA_curve_types.h"
+#include "DNA_curves_types.h"
 #include "DNA_lattice_types.h"
 #include "DNA_meta_types.h"
 #include "DNA_object_types.h"
@@ -30,6 +31,7 @@
 #include "DEG_depsgraph.h"
 
 #include "ED_armature.h"
+#include "ED_curves.h"
 
 #include "ED_transverts.h" /* own include */
 
@@ -181,8 +183,14 @@ static void set_mapped_co(void *vuserdata, int index, const float co[3], const f
 
 bool ED_transverts_check_obedit(const Object *obedit)
 {
-  return (
-      ELEM(obedit->type, OB_ARMATURE, OB_LATTICE, OB_MESH, OB_SURF, OB_CURVES_LEGACY, OB_MBALL));
+  return (ELEM(obedit->type,
+               OB_ARMATURE,
+               OB_LATTICE,
+               OB_MESH,
+               OB_SURF,
+               OB_CURVES_LEGACY,
+               OB_MBALL,
+               OB_CURVES));
 }
 
 void ED_transverts_create_from_obedit(TransVertStore *tvs, const Object *obedit, const int mode)
@@ -481,6 +489,10 @@ void ED_transverts_create_from_obedit(TransVertStore *tvs, const Object *obedit,
       bp++;
     }
   }
+  else if (obedit->type == OB_CURVES) {
+    Curves *curves_id = obedit->data;
+    ED_curves_transverts_create(curves_id, tvs);
+  }
 
   if (!tvs->transverts_tot && tvs->transverts) {
     /* Prevent memory leak. happens for curves/lattices due to