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

7 files changed, 44 insertions, 21 deletions

diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_fillet.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_fillet.cc
index e200350dc18..057e08cc33d 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_curve_fillet.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_fillet.cc
@@ -603,10 +603,13 @@ static void calculate_curve_fillet(GeometrySet &geometry_set,
 
   fillet_param.limit_radius = limit_radius;
 
+  const Curves &src_curves_id = *geometry_set.get_curves_for_read();
   const std::unique_ptr<CurveEval> input_curve = curves_to_curve_eval(*component.get_for_read());
   std::unique_ptr<CurveEval> output_curve = fillet_curve(*input_curve, fillet_param);
 
-  geometry_set.replace_curves(curve_eval_to_curves(*output_curve));
+  Curves *dst_curves_id = curve_eval_to_curves(*output_curve);
+  bke::curves_copy_parameters(src_curves_id, *dst_curves_id);
+  geometry_set.replace_curves(dst_curves_id);
 }
 
 static void node_geo_exec(GeoNodeExecParams params)
diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_resample.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_resample.cc
index 78a132064ed..2815dd5b2e8 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_curve_resample.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_resample.cc
@@ -65,8 +65,10 @@ static void node_geo_exec(GeoNodeExecParams params)
       Field<int> count = params.extract_input<Field<int>>("Count");
       geometry_set.modify_geometry_sets([&](GeometrySet &geometry) {
         if (const CurveComponent *component = geometry.get_component_for_read<CurveComponent>()) {
-          if (!component->is_empty()) {
-            geometry.replace_curves(geometry::resample_to_count(*component, selection, count));
+          if (const Curves *src_curves = component->get_for_read()) {
+            Curves *dst_curves = geometry::resample_to_count(*component, selection, count);
+            bke::curves_copy_parameters(*src_curves, *dst_curves);
+            geometry.replace_curves(dst_curves);
           }
         }
       });
@@ -76,8 +78,10 @@ static void node_geo_exec(GeoNodeExecParams params)
       Field<float> length = params.extract_input<Field<float>>("Length");
       geometry_set.modify_geometry_sets([&](GeometrySet &geometry) {
         if (const CurveComponent *component = geometry.get_component_for_read<CurveComponent>()) {
-          if (!component->is_empty()) {
-            geometry.replace_curves(geometry::resample_to_length(*component, selection, length));
+          if (const Curves *src_curves = component->get_for_read()) {
+            Curves *dst_curves = geometry::resample_to_length(*component, selection, length);
+            bke::curves_copy_parameters(*src_curves, *dst_curves);
+            geometry.replace_curves(dst_curves);
           }
         }
       });
@@ -86,8 +90,10 @@ static void node_geo_exec(GeoNodeExecParams params)
     case GEO_NODE_CURVE_RESAMPLE_EVALUATED:
       geometry_set.modify_geometry_sets([&](GeometrySet &geometry) {
         if (const CurveComponent *component = geometry.get_component_for_read<CurveComponent>()) {
-          if (!component->is_empty()) {
-            geometry.replace_curves(geometry::resample_to_evaluated(*component, selection));
+          if (const Curves *src_curves = component->get_for_read()) {
+            Curves *dst_curves = geometry::resample_to_evaluated(*component, selection);
+            bke::curves_copy_parameters(*src_curves, *dst_curves);
+            geometry.replace_curves(dst_curves);
           }
         }
       });
diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_spline_type.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_spline_type.cc
index 183c98e9c9f..a92479bc5f1 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_curve_spline_type.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_spline_type.cc
@@ -61,15 +61,18 @@ static void node_geo_exec(GeoNodeExecParams params)
       return;
     }
 
-    if (geometry::try_curves_conversion_in_place(selection, dst_type, [&]() -> Curves & {
-          return *geometry_set.get_curves_for_write();
-        })) {
+    if (geometry::try_curves_conversion_in_place(
+            selection, dst_type, [&]() -> bke::CurvesGeometry & {
+              return bke::CurvesGeometry::wrap(geometry_set.get_curves_for_write()->geometry);
+            })) {
       return;
     }
 
-    Curves *dst_curves = geometry::convert_curves(src_component, src_curves, selection, dst_type);
+    bke::CurvesGeometry dst_curves = geometry::convert_curves(src_curves, selection, dst_type);
 
-    geometry_set.replace_curves(dst_curves);
+    Curves *dst_curves_id = bke::curves_new_nomain(std::move(dst_curves));
+    bke::curves_copy_parameters(src_curves_id, *dst_curves_id);
+    geometry_set.replace_curves(dst_curves_id);
   });
 
   params.set_output("Curve", std::move(geometry_set));
diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_subdivide.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_subdivide.cc
index 864e6289135..bd44adb35a2 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_curve_subdivide.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_subdivide.cc
@@ -35,11 +35,11 @@ static void node_geo_exec(GeoNodeExecParams params)
     }
 
     const CurveComponent &component = *geometry_set.get_component_for_read<CurveComponent>();
-    const bke::CurvesGeometry &curves = bke::CurvesGeometry::wrap(
-        component.get_for_read()->geometry);
+    const Curves &src_curves_id = *component.get_for_read();
+    const bke::CurvesGeometry &src_curves = bke::CurvesGeometry::wrap(src_curves_id.geometry);
 
     GeometryComponentFieldContext field_context{component, ATTR_DOMAIN_POINT};
-    fn::FieldEvaluator evaluator{field_context, curves.points_num()};
+    fn::FieldEvaluator evaluator{field_context, src_curves.points_num()};
     evaluator.add(cuts_field);
     evaluator.evaluate();
     const VArray<int> cuts = evaluator.get_evaluated<int>(0);
@@ -47,9 +47,12 @@ static void node_geo_exec(GeoNodeExecParams params)
       return;
     }
 
-    Curves *result = geometry::subdivide_curves(component, curves, curves.curves_range(), cuts);
+    bke::CurvesGeometry dst_curves = geometry::subdivide_curves(
+        src_curves, src_curves.curves_range(), cuts);
 
-    geometry_set.replace_curves(result);
+    Curves *dst_curves_id = bke::curves_new_nomain(std::move(dst_curves));
+    bke::curves_copy_parameters(src_curves_id, *dst_curves_id);
+    geometry_set.replace_curves(dst_curves_id);
   });
   params.set_output("Curve", geometry_set);
 }
diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_trim.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_trim.cc
index 00a79168087..51994cb8a41 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_curve_trim.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_trim.cc
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 
+#include "BKE_curves.hh"
 #include "BKE_spline.hh"
 #include "BLI_task.hh"
 
@@ -515,7 +516,8 @@ static void geometry_set_curve_trim(GeometrySet &geometry_set,
   const VArray<float> starts = evaluator.get_evaluated<float>(0);
   const VArray<float> ends = evaluator.get_evaluated<float>(1);
 
-  std::unique_ptr<CurveEval> curve = curves_to_curve_eval(*geometry_set.get_curves_for_read());
+  const Curves &src_curves_id = *geometry_set.get_curves_for_read();
+  std::unique_ptr<CurveEval> curve = curves_to_curve_eval(src_curves_id);
   MutableSpan<SplinePtr> splines = curve->splines();
 
   threading::parallel_for(splines.index_range(), 128, [&](IndexRange range) {
@@ -566,7 +568,9 @@ static void geometry_set_curve_trim(GeometrySet &geometry_set,
     }
   });
 
-  geometry_set.replace_curves(curve_eval_to_curves(*curve));
+  Curves *dst_curves_id = curve_eval_to_curves(*curve);
+  bke::curves_copy_parameters(src_curves_id, *dst_curves_id);
+  geometry_set.replace_curves(dst_curves_id);
 }
 
 static void node_geo_exec(GeoNodeExecParams params)
diff --git a/source/blender/nodes/geometry/nodes/node_geo_duplicate_elements.cc b/source/blender/nodes/geometry/nodes/node_geo_duplicate_elements.cc
index 41136060ab7..8160bc8d589 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_duplicate_elements.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_duplicate_elements.cc
@@ -369,6 +369,7 @@ static void duplicate_curves(GeometrySet &geometry_set,
   point_offsets.last() = dst_points_num;
 
   Curves *new_curves_id = bke::curves_new_nomain(dst_points_num, dst_curves_num);
+  bke::curves_copy_parameters(curves_id, *new_curves_id);
   bke::CurvesGeometry &new_curves = bke::CurvesGeometry::wrap(new_curves_id->geometry);
   MutableSpan<int> all_dst_offsets = new_curves.offsets_for_write();
 
@@ -830,6 +831,7 @@ static void duplicate_points_curve(GeometrySet &geometry_set,
   });
 
   Curves *new_curves_id = bke::curves_new_nomain(dst_num, dst_num);
+  bke::curves_copy_parameters(src_curves_id, *new_curves_id);
   bke::CurvesGeometry &new_curves = bke::CurvesGeometry::wrap(new_curves_id->geometry);
   MutableSpan<int> new_curve_offsets = new_curves.offsets_for_write();
   for (const int i : new_curves.curves_range()) {
diff --git a/source/blender/nodes/geometry/nodes/node_geo_mesh_to_curve.cc b/source/blender/nodes/geometry/nodes/node_geo_mesh_to_curve.cc
index f6ee3d00dee..4a79ec159f4 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_mesh_to_curve.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_mesh_to_curve.cc
@@ -18,7 +18,8 @@ static void node_geo_exec(GeoNodeExecParams params)
   GeometrySet geometry_set = params.extract_input<GeometrySet>("Mesh");
 
   geometry_set.modify_geometry_sets([&](GeometrySet &geometry_set) {
-    if (!geometry_set.has_mesh()) {
+    const Mesh *mesh = geometry_set.get_mesh_for_read();
+    if (mesh == nullptr) {
       geometry_set.keep_only({GEO_COMPONENT_TYPE_INSTANCES});
       return;
     }
@@ -34,7 +35,8 @@ static void node_geo_exec(GeoNodeExecParams params)
       return;
     }
 
-    geometry_set.replace_curves(geometry::mesh_to_curve_convert(component, selection));
+    bke::CurvesGeometry curves = geometry::mesh_to_curve_convert(*mesh, selection);
+    geometry_set.replace_curves(bke::curves_new_nomain(std::move(curves)));
     geometry_set.keep_only({GEO_COMPONENT_TYPE_CURVE, GEO_COMPONENT_TYPE_INSTANCES});
   });