4 files changed, 42 insertions, 0 deletions
diff --git a/source/blender/blenkernel/BKE_curves.hh b/source/blender/blenkernel/BKE_curves.hh
index fb97e52f6da..25a912b8825 100644
--- a/source/blender/blenkernel/BKE_curves.hh
+++ b/source/blender/blenkernel/BKE_curves.hh
@@ -735,6 +735,12 @@ Curves *curves_new_nomain(CurvesGeometry curves);
  */
 Curves *curves_new_nomain_single(int points_num, CurveType type);
 
+/**
+ * Copy data from #src to #dst, except the geometry data in #CurvesGeometry. Typically used to
+ * copy high-level parameters when a geometry-altering operation creates a new curves data-block.
+ */
+void curves_copy_parameters(const Curves &src, Curves &dst);
+
 std::array<int, CURVE_TYPES_NUM> calculate_type_counts(const VArray<int8_t> &types);
 
 /* -------------------------------------------------------------------- */
diff --git a/source/blender/blenkernel/BKE_curves_utils.hh b/source/blender/blenkernel/BKE_curves_utils.hh
index f223e173ea9..0fbd33002e1 100644
--- a/source/blender/blenkernel/BKE_curves_utils.hh
+++ b/source/blender/blenkernel/BKE_curves_utils.hh
@@ -56,6 +56,13 @@ void fill_points(const CurvesGeometry &curves,
 }
 
 /**
+ * Copy only the information on the point domain, but not the offsets or any point attributes,
+ * meant for operations that change the number of points but not the number of curves.
+ * \warning The returned curves have invalid offsets!
+ */
+bke::CurvesGeometry copy_only_curve_domain(const bke::CurvesGeometry &src_curves);
+
+/**
  * Copy the size of every curve in #curve_ranges to the corresponding index in #counts.
  */
 void fill_curve_counts(const bke::CurvesGeometry &curves,
diff --git a/source/blender/blenkernel/intern/curves.cc b/source/blender/blenkernel/intern/curves.cc
index 78791b55b4d..7e9f994313b 100644
--- a/source/blender/blenkernel/intern/curves.cc
+++ b/source/blender/blenkernel/intern/curves.cc
@@ -388,6 +388,23 @@ Curves *curves_new_nomain(CurvesGeometry curves)
   return curves_id;
 }
 
+void curves_copy_parameters(const Curves &src, Curves &dst)
+{
+  dst.flag = src.flag;
+  dst.attributes_active_index = src.attributes_active_index;
+  MEM_SAFE_FREE(dst.mat);
+  dst.mat = static_cast<Material **>(MEM_malloc_arrayN(src.totcol, sizeof(Material *), __func__));
+  dst.totcol = src.totcol;
+  MutableSpan(dst.mat, dst.totcol).copy_from(Span(src.mat, src.totcol));
+  dst.symmetry = src.symmetry;
+  dst.selection_domain = src.selection_domain;
+  dst.surface = src.surface;
+  MEM_SAFE_FREE(dst.surface_uv_map);
+  if (src.surface_uv_map != nullptr) {
+    dst.surface_uv_map = BLI_strdup(src.surface_uv_map);
+  }
+}
+
 CurvesSurfaceTransforms::CurvesSurfaceTransforms(const Object &curves_ob, const Object *surface_ob)
 {
   this->curves_to_world = curves_ob.obmat;
diff --git a/source/blender/blenkernel/intern/curves_utils.cc b/source/blender/blenkernel/intern/curves_utils.cc
index f7db60ee588..d98832e796c 100644
--- a/source/blender/blenkernel/intern/curves_utils.cc
+++ b/source/blender/blenkernel/intern/curves_utils.cc
@@ -84,6 +84,18 @@ void fill_points(const CurvesGeometry &curves,
   });
 }
 
+bke::CurvesGeometry copy_only_curve_domain(const bke::CurvesGeometry &src_curves)
+{
+  bke::CurvesGeometry dst_curves(0, src_curves.curves_num());
+  CustomData_copy(&src_curves.curve_data,
+                  &dst_curves.curve_data,
+                  CD_MASK_ALL,
+                  CD_DUPLICATE,
+                  src_curves.curves_num());
+  dst_curves.runtime->type_counts = src_curves.runtime->type_counts;
+  return dst_curves;
+}
+
 IndexMask indices_for_type(const VArray<int8_t> &types,
                            const std::array<int, CURVE_TYPES_NUM> &type_counts,
                            const CurveType type,