Geometry Nodes: Copy parameters when copying a curves data-block

Previously, things like materials, symmetry, and selection options
stored on `Curves` weren't copied to the result in nodes like the
subdivide and resample nodes. Now they are, which fixes some
unexpected behavior and allows visualization of the sculpt mode
selection.

In the realize instances and join nodes the behavior is the same as
for meshes, the parameters are taken from the first (top) input.

I also refactored some functions to return a `CurvesGeometry` by-value,
which makes it the responsibility of the node to copy the parameters.
That should make the algorithms more reusable in other situations.

Differential Revision: https://developer.blender.org/D15408

1 files changed, 7 insertions, 31 deletions

diff --git a/source/blender/geometry/intern/subdivide_curves.cc b/source/blender/geometry/intern/subdivide_curves.cc
index 914174235cd..b6476d19818 100644
--- a/source/blender/geometry/intern/subdivide_curves.cc
+++ b/source/blender/geometry/intern/subdivide_curves.cc
@@ -12,26 +12,6 @@
 namespace blender::geometry {
 
 /**
- * \warning Only the curve domain of the input is copied, so the result is invalid!
- */
-static Curves *create_result_curves(const bke::CurvesGeometry &src_curves)
-{
-  Curves *dst_curves_id = bke::curves_new_nomain(0, src_curves.curves_num());
-  bke::CurvesGeometry &dst_curves = bke::CurvesGeometry::wrap(dst_curves_id->geometry);
-  CurveComponent dst_component;
-  dst_component.replace(dst_curves_id, GeometryOwnershipType::Editable);
-  /* Directly copy curve attributes, since they stay the same. */
-  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_id;
-}
-
-/**
  * Return a range used to retrieve values from an array of values stored per point, but with an
  * extra element at the end of each curve. This is useful for offsets within curves, where it is
  * convenient to store the first 0 and have the last offset be the total result curve size.
@@ -342,10 +322,9 @@ static void subdivide_bezier_positions(const Span<float3> src_positions,
       cyclic, dst_types_l, dst_types_r, dst_positions, dst_handles_l, dst_handles_r);
 }
 
-Curves *subdivide_curves(const CurveComponent &src_component,
-                         const bke::CurvesGeometry &src_curves,
-                         const IndexMask selection,
-                         const VArray<int> &cuts)
+bke::CurvesGeometry subdivide_curves(const bke::CurvesGeometry &src_curves,
+                                     const IndexMask selection,
+                                     const VArray<int> &cuts)
 {
   const Vector<IndexRange> unselected_ranges = selection.extract_ranges_invert(
       src_curves.curves_range());
@@ -353,10 +332,7 @@ Curves *subdivide_curves(const CurveComponent &src_component,
   /* Cyclic is accessed a lot, it's probably worth it to make sure it's a span. */
   const VArraySpan<bool> cyclic{src_curves.cyclic()};
 
-  Curves *dst_curves_id = create_result_curves(src_curves);
-  bke::CurvesGeometry &dst_curves = bke::CurvesGeometry::wrap(dst_curves_id->geometry);
-  CurveComponent dst_component;
-  dst_component.replace(dst_curves_id, GeometryOwnershipType::Editable);
+  bke::CurvesGeometry dst_curves = bke::curves::copy_only_curve_domain(src_curves);
 
   /* For each point, this contains the point offset in the corresponding result curve,
    * starting at zero. For example for two curves with four points each, the values might
@@ -385,8 +361,8 @@ Curves *subdivide_curves(const CurveComponent &src_component,
 
   dst_curves.resize(dst_curves.offsets().last(), dst_curves.curves_num());
 
-  const bke::AttributeAccessor src_attributes = *src_component.attributes();
-  bke::MutableAttributeAccessor dst_attributes = *dst_component.attributes_for_write();
+  const bke::AttributeAccessor src_attributes = src_curves.attributes();
+  bke::MutableAttributeAccessor dst_attributes = dst_curves.attributes_for_write();
 
   auto subdivide_catmull_rom = [&](IndexMask selection) {
     for (auto &attribute : retrieve_point_attributes(src_attributes, dst_attributes)) {
@@ -476,7 +452,7 @@ Curves *subdivide_curves(const CurveComponent &src_component,
     }
   }
 
-  return dst_curves_id;
+  return dst_curves;
 }
 
 }  // namespace blender::geometry