Merge branch 'master' into tmp-vulkan

1 files changed, 791 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/curve_to_mesh_convert.cc b/source/blender/blenkernel/intern/curve_to_mesh_convert.cc
new file mode 100644
index 00000000000..1ef205c6903
--- /dev/null
+++ b/source/blender/blenkernel/intern/curve_to_mesh_convert.cc
@@ -0,0 +1,791 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "BLI_array.hh"
+#include "BLI_set.hh"
+#include "BLI_task.hh"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+
+#include "BKE_attribute_access.hh"
+#include "BKE_attribute_math.hh"
+#include "BKE_geometry_set.hh"
+#include "BKE_material.h"
+#include "BKE_mesh.h"
+#include "BKE_spline.hh"
+
+#include "BKE_curve_to_mesh.hh"
+
+using blender::fn::GMutableSpan;
+using blender::fn::GSpan;
+using blender::fn::GVArray_Typed;
+using blender::fn::GVArrayPtr;
+
+namespace blender::bke {
+
+/** Information about the creation of one curve spline and profile spline combination. */
+struct ResultInfo {
+  const Spline &spline;
+  const Spline &profile;
+  int vert_offset;
+  int edge_offset;
+  int loop_offset;
+  int poly_offset;
+  int spline_vert_len;
+  int spline_edge_len;
+  int profile_vert_len;
+  int profile_edge_len;
+};
+
+static void vert_extrude_to_mesh_data(const Spline &spline,
+                                      const float3 profile_vert,
+                                      MutableSpan<MVert> r_verts,
+                                      MutableSpan<MEdge> r_edges,
+                                      const int vert_offset,
+                                      const int edge_offset)
+{
+  const int eval_size = spline.evaluated_points_size();
+  for (const int i : IndexRange(eval_size - 1)) {
+    MEdge &edge = r_edges[edge_offset + i];
+    edge.v1 = vert_offset + i;
+    edge.v2 = vert_offset + i + 1;
+    edge.flag = ME_LOOSEEDGE;
+  }
+
+  if (spline.is_cyclic() && spline.evaluated_edges_size() > 1) {
+    MEdge &edge = r_edges[edge_offset + spline.evaluated_edges_size() - 1];
+    edge.v1 = vert_offset;
+    edge.v2 = vert_offset + eval_size - 1;
+    edge.flag = ME_LOOSEEDGE;
+  }
+
+  Span<float3> positions = spline.evaluated_positions();
+  Span<float3> tangents = spline.evaluated_tangents();
+  Span<float3> normals = spline.evaluated_normals();
+  GVArray_Typed<float> radii = spline.interpolate_to_evaluated(spline.radii());
+  for (const int i : IndexRange(eval_size)) {
+    float4x4 point_matrix = float4x4::from_normalized_axis_data(
+        positions[i], normals[i], tangents[i]);
+    point_matrix.apply_scale(radii[i]);
+
+    MVert &vert = r_verts[vert_offset + i];
+    copy_v3_v3(vert.co, point_matrix * profile_vert);
+  }
+}
+
+static void mark_edges_sharp(MutableSpan<MEdge> edges)
+{
+  for (MEdge &edge : edges) {
+    edge.flag |= ME_SHARP;
+  }
+}
+
+static void spline_extrude_to_mesh_data(const ResultInfo &info,
+                                        const bool fill_caps,
+                                        MutableSpan<MVert> r_verts,
+                                        MutableSpan<MEdge> r_edges,
+                                        MutableSpan<MLoop> r_loops,
+                                        MutableSpan<MPoly> r_polys)
+{
+  const Spline &spline = info.spline;
+  const Spline &profile = info.profile;
+  if (info.profile_vert_len == 1) {
+    vert_extrude_to_mesh_data(spline,
+                              profile.evaluated_positions()[0],
+                              r_verts,
+                              r_edges,
+                              info.vert_offset,
+                              info.edge_offset);
+    return;
+  }
+
+  /* Add the edges running along the length of the curve, starting at each profile vertex. */
+  const int spline_edges_start = info.edge_offset;
+  for (const int i_profile : IndexRange(info.profile_vert_len)) {
+    const int profile_edge_offset = spline_edges_start + i_profile * info.spline_edge_len;
+    for (const int i_ring : IndexRange(info.spline_edge_len)) {
+      const int i_next_ring = (i_ring == info.spline_vert_len - 1) ? 0 : i_ring + 1;
+
+      const int ring_vert_offset = info.vert_offset + info.profile_vert_len * i_ring;
+      const int next_ring_vert_offset = info.vert_offset + info.profile_vert_len * i_next_ring;
+
+      MEdge &edge = r_edges[profile_edge_offset + i_ring];
+      edge.v1 = ring_vert_offset + i_profile;
+      edge.v2 = next_ring_vert_offset + i_profile;
+      edge.flag = ME_EDGEDRAW | ME_EDGERENDER;
+    }
+  }
+
+  /* Add the edges running along each profile ring. */
+  const int profile_edges_start = spline_edges_start +
+                                  info.profile_vert_len * info.spline_edge_len;
+  for (const int i_ring : IndexRange(info.spline_vert_len)) {
+    const int ring_vert_offset = info.vert_offset + info.profile_vert_len * i_ring;
+
+    const int ring_edge_offset = profile_edges_start + i_ring * info.profile_edge_len;
+    for (const int i_profile : IndexRange(info.profile_edge_len)) {
+      const int i_next_profile = (i_profile == info.profile_vert_len - 1) ? 0 : i_profile + 1;
+
+      MEdge &edge = r_edges[ring_edge_offset + i_profile];
+      edge.v1 = ring_vert_offset + i_profile;
+      edge.v2 = ring_vert_offset + i_next_profile;
+      edge.flag = ME_EDGEDRAW | ME_EDGERENDER;
+    }
+  }
+
+  /* Calculate poly and corner indices. */
+  for (const int i_ring : IndexRange(info.spline_edge_len)) {
+    const int i_next_ring = (i_ring == info.spline_vert_len - 1) ? 0 : i_ring + 1;
+
+    const int ring_vert_offset = info.vert_offset + info.profile_vert_len * i_ring;
+    const int next_ring_vert_offset = info.vert_offset + info.profile_vert_len * i_next_ring;
+
+    const int ring_edge_start = profile_edges_start + info.profile_edge_len * i_ring;
+    const int next_ring_edge_offset = profile_edges_start + info.profile_edge_len * i_next_ring;
+
+    const int ring_poly_offset = info.poly_offset + i_ring * info.profile_edge_len;
+    const int ring_loop_offset = info.loop_offset + i_ring * info.profile_edge_len * 4;
+
+    for (const int i_profile : IndexRange(info.profile_edge_len)) {
+      const int ring_segment_loop_offset = ring_loop_offset + i_profile * 4;
+      const int i_next_profile = (i_profile == info.profile_vert_len - 1) ? 0 : i_profile + 1;
+
+      const int spline_edge_start = spline_edges_start + info.spline_edge_len * i_profile;
+      const int next_spline_edge_start = spline_edges_start +
+                                         info.spline_edge_len * i_next_profile;
+
+      MPoly &poly = r_polys[ring_poly_offset + i_profile];
+      poly.loopstart = ring_segment_loop_offset;
+      poly.totloop = 4;
+      poly.flag = ME_SMOOTH;
+
+      MLoop &loop_a = r_loops[ring_segment_loop_offset];
+      loop_a.v = ring_vert_offset + i_profile;
+      loop_a.e = ring_edge_start + i_profile;
+      MLoop &loop_b = r_loops[ring_segment_loop_offset + 1];
+      loop_b.v = ring_vert_offset + i_next_profile;
+      loop_b.e = next_spline_edge_start + i_ring;
+      MLoop &loop_c = r_loops[ring_segment_loop_offset + 2];
+      loop_c.v = next_ring_vert_offset + i_next_profile;
+      loop_c.e = next_ring_edge_offset + i_profile;
+      MLoop &loop_d = r_loops[ring_segment_loop_offset + 3];
+      loop_d.v = next_ring_vert_offset + i_profile;
+      loop_d.e = spline_edge_start + i_ring;
+    }
+  }
+
+  if (fill_caps && profile.is_cyclic()) {
+    const int poly_size = info.spline_edge_len * info.profile_edge_len;
+    const int cap_loop_offset = info.loop_offset + poly_size * 4;
+    const int cap_poly_offset = info.poly_offset + poly_size;
+
+    MPoly &poly_start = r_polys[cap_poly_offset];
+    poly_start.loopstart = cap_loop_offset;
+    poly_start.totloop = info.profile_edge_len;
+    MPoly &poly_end = r_polys[cap_poly_offset + 1];
+    poly_end.loopstart = cap_loop_offset + info.profile_edge_len;
+    poly_end.totloop = info.profile_edge_len;
+
+    const int last_ring_index = info.spline_vert_len - 1;
+    const int last_ring_vert_offset = info.vert_offset + info.profile_vert_len * last_ring_index;
+    const int last_ring_edge_offset = profile_edges_start +
+                                      info.profile_edge_len * last_ring_index;
+
+    for (const int i : IndexRange(info.profile_edge_len)) {
+      const int i_inv = info.profile_edge_len - i - 1;
+      MLoop &loop_start = r_loops[cap_loop_offset + i];
+      loop_start.v = info.vert_offset + i_inv;
+      loop_start.e = profile_edges_start + ((i == (info.profile_edge_len - 1)) ?
+                                                (info.profile_edge_len - 1) :
+                                                (i_inv - 1));
+      MLoop &loop_end = r_loops[cap_loop_offset + info.profile_edge_len + i];
+      loop_end.v = last_ring_vert_offset + i;
+      loop_end.e = last_ring_edge_offset + i;
+    }
+
+    mark_edges_sharp(r_edges.slice(profile_edges_start, info.profile_edge_len));
+    mark_edges_sharp(r_edges.slice(last_ring_edge_offset, info.profile_edge_len));
+  }
+
+  /* Calculate the positions of each profile ring profile along the spline. */
+  Span<float3> positions = spline.evaluated_positions();
+  Span<float3> tangents = spline.evaluated_tangents();
+  Span<float3> normals = spline.evaluated_normals();
+  Span<float3> profile_positions = profile.evaluated_positions();
+
+  GVArray_Typed<float> radii = spline.interpolate_to_evaluated(spline.radii());
+  for (const int i_ring : IndexRange(info.spline_vert_len)) {
+    float4x4 point_matrix = float4x4::from_normalized_axis_data(
+        positions[i_ring], normals[i_ring], tangents[i_ring]);
+    point_matrix.apply_scale(radii[i_ring]);
+
+    const int ring_vert_start = info.vert_offset + i_ring * info.profile_vert_len;
+    for (const int i_profile : IndexRange(info.profile_vert_len)) {
+      MVert &vert = r_verts[ring_vert_start + i_profile];
+      copy_v3_v3(vert.co, point_matrix * profile_positions[i_profile]);
+    }
+  }
+
+  /* Mark edge loops from sharp vector control points sharp. */
+  if (profile.type() == Spline::Type::Bezier) {
+    const BezierSpline &bezier_spline = static_cast<const BezierSpline &>(profile);
+    Span<int> control_point_offsets = bezier_spline.control_point_offsets();
+    for (const int i : IndexRange(bezier_spline.size())) {
+      if (bezier_spline.point_is_sharp(i)) {
+        mark_edges_sharp(
+            r_edges.slice(spline_edges_start + info.spline_edge_len * control_point_offsets[i],
+                          info.spline_edge_len));
+      }
+    }
+  }
+}
+
+static inline int spline_extrude_vert_size(const Spline &curve, const Spline &profile)
+{
+  return curve.evaluated_points_size() * profile.evaluated_points_size();
+}
+
+static inline int spline_extrude_edge_size(const Spline &curve, const Spline &profile)
+{
+  /* Add the ring edges, with one ring for every curve vertex, and the edge loops
+   * that run along the length of the curve, starting on the first profile. */
+  return curve.evaluated_points_size() * profile.evaluated_edges_size() +
+         curve.evaluated_edges_size() * profile.evaluated_points_size();
+}
+
+static inline int spline_extrude_loop_size(const Spline &curve,
+                                           const Spline &profile,
+                                           const bool fill_caps)
+{
+  const int tube = curve.evaluated_edges_size() * profile.evaluated_edges_size() * 4;
+  const int caps = (fill_caps && profile.is_cyclic()) ? profile.evaluated_edges_size() * 2 : 0;
+  return tube + caps;
+}
+
+static inline int spline_extrude_poly_size(const Spline &curve,
+                                           const Spline &profile,
+                                           const bool fill_caps)
+{
+  const int tube = curve.evaluated_edges_size() * profile.evaluated_edges_size();
+  const int caps = (fill_caps && profile.is_cyclic()) ? 2 : 0;
+  return tube + caps;
+}
+
+struct ResultOffsets {
+  Array<int> vert;
+  Array<int> edge;
+  Array<int> loop;
+  Array<int> poly;
+};
+static ResultOffsets calculate_result_offsets(Span<SplinePtr> profiles,
+                                              Span<SplinePtr> curves,
+                                              const bool fill_caps)
+{
+  const int total = profiles.size() * curves.size();
+  Array<int> vert(total + 1);
+  Array<int> edge(total + 1);
+  Array<int> loop(total + 1);
+  Array<int> poly(total + 1);
+
+  int mesh_index = 0;
+  int vert_offset = 0;
+  int edge_offset = 0;
+  int loop_offset = 0;
+  int poly_offset = 0;
+  for (const int i_spline : curves.index_range()) {
+    for (const int i_profile : profiles.index_range()) {
+      vert[mesh_index] = vert_offset;
+      edge[mesh_index] = edge_offset;
+      loop[mesh_index] = loop_offset;
+      poly[mesh_index] = poly_offset;
+      vert_offset += spline_extrude_vert_size(*curves[i_spline], *profiles[i_profile]);
+      edge_offset += spline_extrude_edge_size(*curves[i_spline], *profiles[i_profile]);
+      loop_offset += spline_extrude_loop_size(*curves[i_spline], *profiles[i_profile], fill_caps);
+      poly_offset += spline_extrude_poly_size(*curves[i_spline], *profiles[i_profile], fill_caps);
+      mesh_index++;
+    }
+  }
+  vert.last() = vert_offset;
+  edge.last() = edge_offset;
+  loop.last() = loop_offset;
+  poly.last() = poly_offset;
+
+  return {std::move(vert), std::move(edge), std::move(loop), std::move(poly)};
+}
+
+static AttributeDomain get_result_attribute_domain(const MeshComponent &component,
+                                                   const AttributeIDRef &attribute_id)
+{
+  /* Only use a different domain if it is builtin and must only exist on one domain. */
+  if (!component.attribute_is_builtin(attribute_id)) {
+    return ATTR_DOMAIN_POINT;
+  }
+
+  std::optional<AttributeMetaData> meta_data = component.attribute_get_meta_data(attribute_id);
+  if (!meta_data) {
+    /* This function has to return something in this case, but it shouldn't be used,
+     * so return an output that will assert later if the code attempts to handle it. */
+    return ATTR_DOMAIN_AUTO;
+  }
+
+  return meta_data->domain;
+}
+
+/**
+ * The data stored in the attribute and its domain from #OutputAttribute, to avoid calling
+ * `as_span()` for every single profile and curve spline combination, and for readability.
+ */
+struct ResultAttributeData {
+  GMutableSpan data;
+  AttributeDomain domain;
+};
+
+static std::optional<ResultAttributeData> create_attribute_and_get_span(
+    MeshComponent &component,
+    const AttributeIDRef &attribute_id,
+    AttributeMetaData meta_data,
+    Vector<OutputAttribute> &r_attributes)
+{
+  const AttributeDomain domain = get_result_attribute_domain(component, attribute_id);
+  OutputAttribute attribute = component.attribute_try_get_for_output_only(
+      attribute_id, domain, meta_data.data_type);
+  if (!attribute) {
+    return std::nullopt;
+  }
+
+  GMutableSpan span = attribute.as_span();
+  r_attributes.append(std::move(attribute));
+  return std::make_optional<ResultAttributeData>({span, domain});
+}
+
+/**
+ * Store the references to the attribute data from the curve and profile inputs. Here we rely on
+ * the invariants of the storage of curve attributes, that the order will be consistent between
+ * splines, and all splines will have the same attributes.
+ */
+struct ResultAttributes {
+  /**
+   * Result attributes on the mesh corresponding to each attribute on the curve input, in the same
+   * order. The data is optional only in case the attribute does not exist on the mesh for some
+   * reason, like "shade_smooth" when the result has no faces.
+   */
+  Vector<std::optional<ResultAttributeData>> curve_point_attributes;
+  Vector<std::optional<ResultAttributeData>> curve_spline_attributes;
+
+  /**
+   * Result attributes corresponding the attributes on the profile input, in the same order. The
+   * attributes are optional in case the attribute names correspond to a names used by the curve
+   * input, in which case the curve input attributes take precedence.
+   */
+  Vector<std::optional<ResultAttributeData>> profile_point_attributes;
+  Vector<std::optional<ResultAttributeData>> profile_spline_attributes;
+
+  /**
+   * Because some builtin attributes are not stored contiguously, and the curve inputs might have
+   * attributes with those names, it's necessary to keep OutputAttributes around to give access to
+   * the result data in a contiguous array.
+   */
+  Vector<OutputAttribute> attributes;
+};
+static ResultAttributes create_result_attributes(const CurveEval &curve,
+                                                 const CurveEval &profile,
+                                                 Mesh &mesh)
+{
+  MeshComponent mesh_component;
+  mesh_component.replace(&mesh, GeometryOwnershipType::Editable);
+  Set<AttributeIDRef> curve_attributes;
+
+  /* In order to prefer attributes on the main curve input when there are name collisions, first
+   * check the attributes on the curve, then add attributes on the profile that are not also on the
+   * main curve input. */
+  ResultAttributes result;
+  curve.splines().first()->attributes.foreach_attribute(
+      [&](const AttributeIDRef &id, const AttributeMetaData &meta_data) {
+        curve_attributes.add_new(id);
+        result.curve_point_attributes.append(
+            create_attribute_and_get_span(mesh_component, id, meta_data, result.attributes));
+        return true;
+      },
+      ATTR_DOMAIN_POINT);
+  curve.attributes.foreach_attribute(
+      [&](const AttributeIDRef &id, const AttributeMetaData &meta_data) {
+        curve_attributes.add_new(id);
+        result.curve_spline_attributes.append(
+            create_attribute_and_get_span(mesh_component, id, meta_data, result.attributes));
+        return true;
+      },
+      ATTR_DOMAIN_CURVE);
+  profile.splines().first()->attributes.foreach_attribute(
+      [&](const AttributeIDRef &id, const AttributeMetaData &meta_data) {
+        if (curve_attributes.contains(id)) {
+          result.profile_point_attributes.append({});
+        }
+        else {
+          result.profile_point_attributes.append(
+              create_attribute_and_get_span(mesh_component, id, meta_data, result.attributes));
+        }
+        return true;
+      },
+      ATTR_DOMAIN_POINT);
+  profile.attributes.foreach_attribute(
+      [&](const AttributeIDRef &id, const AttributeMetaData &meta_data) {
+        if (curve_attributes.contains(id)) {
+          result.profile_spline_attributes.append({});
+        }
+        else {
+          result.profile_spline_attributes.append(
+              create_attribute_and_get_span(mesh_component, id, meta_data, result.attributes));
+        }
+        return true;
+      },
+      ATTR_DOMAIN_CURVE);
+
+  return result;
+}
+
+template<typename T>
+static void copy_curve_point_data_to_mesh_verts(const Span<T> src,
+                                                const ResultInfo &info,
+                                                MutableSpan<T> dst)
+{
+  for (const int i_ring : IndexRange(info.spline_vert_len)) {
+    const int ring_vert_start = info.vert_offset + i_ring * info.profile_vert_len;
+    dst.slice(ring_vert_start, info.profile_vert_len).fill(src[i_ring]);
+  }
+}
+
+template<typename T>
+static void copy_curve_point_data_to_mesh_edges(const Span<T> src,
+                                                const ResultInfo &info,
+                                                MutableSpan<T> dst)
+{
+  const int edges_start = info.edge_offset + info.profile_vert_len * info.spline_edge_len;
+  for (const int i_ring : IndexRange(info.spline_vert_len)) {
+    const int ring_edge_start = edges_start + info.profile_edge_len * i_ring;
+    dst.slice(ring_edge_start, info.profile_edge_len).fill(src[i_ring]);
+  }
+}
+
+template<typename T>
+static void copy_curve_point_data_to_mesh_faces(const Span<T> src,
+                                                const ResultInfo &info,
+                                                MutableSpan<T> dst)
+{
+  for (const int i_ring : IndexRange(info.spline_edge_len)) {
+    const int ring_face_start = info.poly_offset + info.profile_edge_len * i_ring;
+    dst.slice(ring_face_start, info.profile_edge_len).fill(src[i_ring]);
+  }
+}
+
+static void copy_curve_point_attribute_to_mesh(const GSpan src,
+                                               const ResultInfo &info,
+                                               ResultAttributeData &dst)
+{
+  GVArrayPtr interpolated_gvarray = info.spline.interpolate_to_evaluated(src);
+  GSpan interpolated = interpolated_gvarray->get_internal_span();
+
+  attribute_math::convert_to_static_type(src.type(), [&](auto dummy) {
+    using T = decltype(dummy);
+    switch (dst.domain) {
+      case ATTR_DOMAIN_POINT:
+        copy_curve_point_data_to_mesh_verts(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_EDGE:
+        copy_curve_point_data_to_mesh_edges(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_FACE:
+        copy_curve_point_data_to_mesh_faces(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_CORNER:
+        /* Unsupported for now, since there are no builtin attributes to convert into. */
+        break;
+      default:
+        BLI_assert_unreachable();
+        break;
+    }
+  });
+}
+
+template<typename T>
+static void copy_profile_point_data_to_mesh_verts(const Span<T> src,
+                                                  const ResultInfo &info,
+                                                  MutableSpan<T> dst)
+{
+  for (const int i_ring : IndexRange(info.spline_vert_len)) {
+    const int profile_vert_start = info.vert_offset + i_ring * info.profile_vert_len;
+    for (const int i_profile : IndexRange(info.profile_vert_len)) {
+      dst[profile_vert_start + i_profile] = src[i_profile];
+    }
+  }
+}
+
+template<typename T>
+static void copy_profile_point_data_to_mesh_edges(const Span<T> src,
+                                                  const ResultInfo &info,
+                                                  MutableSpan<T> dst)
+{
+  for (const int i_profile : IndexRange(info.profile_vert_len)) {
+    const int profile_edge_offset = info.edge_offset + i_profile * info.spline_edge_len;
+    dst.slice(profile_edge_offset, info.spline_edge_len).fill(src[i_profile]);
+  }
+}
+
+template<typename T>
+static void copy_profile_point_data_to_mesh_faces(const Span<T> src,
+                                                  const ResultInfo &info,
+                                                  MutableSpan<T> dst)
+{
+  for (const int i_ring : IndexRange(info.spline_edge_len)) {
+    const int profile_face_start = info.poly_offset + i_ring * info.profile_edge_len;
+    for (const int i_profile : IndexRange(info.profile_edge_len)) {
+      dst[profile_face_start + i_profile] = src[i_profile];
+    }
+  }
+}
+
+static void copy_profile_point_attribute_to_mesh(const GSpan src,
+                                                 const ResultInfo &info,
+                                                 ResultAttributeData &dst)
+{
+  GVArrayPtr interpolated_gvarray = info.profile.interpolate_to_evaluated(src);
+  GSpan interpolated = interpolated_gvarray->get_internal_span();
+
+  attribute_math::convert_to_static_type(src.type(), [&](auto dummy) {
+    using T = decltype(dummy);
+    switch (dst.domain) {
+      case ATTR_DOMAIN_POINT:
+        copy_profile_point_data_to_mesh_verts(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_EDGE:
+        copy_profile_point_data_to_mesh_edges(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_FACE:
+        copy_profile_point_data_to_mesh_faces(interpolated.typed<T>(), info, dst.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_CORNER:
+        /* Unsupported for now, since there are no builtin attributes to convert into. */
+        break;
+      default:
+        BLI_assert_unreachable();
+        break;
+    }
+  });
+}
+
+static void copy_point_domain_attributes_to_mesh(const ResultInfo &info,
+                                                 ResultAttributes &attributes)
+{
+  if (!attributes.curve_point_attributes.is_empty()) {
+    int i = 0;
+    info.spline.attributes.foreach_attribute(
+        [&](const AttributeIDRef &id, const AttributeMetaData &UNUSED(meta_data)) {
+          if (attributes.curve_point_attributes[i]) {
+            copy_curve_point_attribute_to_mesh(*info.spline.attributes.get_for_read(id),
+                                               info,
+                                               *attributes.curve_point_attributes[i]);
+          }
+          i++;
+          return true;
+        },
+        ATTR_DOMAIN_POINT);
+  }
+  if (!attributes.profile_point_attributes.is_empty()) {
+    int i = 0;
+    info.profile.attributes.foreach_attribute(
+        [&](const AttributeIDRef &id, const AttributeMetaData &UNUSED(meta_data)) {
+          if (attributes.profile_point_attributes[i]) {
+            copy_profile_point_attribute_to_mesh(*info.profile.attributes.get_for_read(id),
+                                                 info,
+                                                 *attributes.profile_point_attributes[i]);
+          }
+          i++;
+          return true;
+        },
+        ATTR_DOMAIN_POINT);
+  }
+}
+
+template<typename T>
+static void copy_spline_data_to_mesh(Span<T> src, Span<int> offsets, MutableSpan<T> dst)
+{
+  for (const int i : IndexRange(src.size())) {
+    dst.slice(offsets[i], offsets[i + 1] - offsets[i]).fill(src[i]);
+  }
+}
+
+/**
+ * Since the offsets for each combination of curve and profile spline are stored for every mesh
+ * domain, and this just needs to fill the chunks corresponding to each combination, we can use
+ * the same function for all mesh domains.
+ */
+static void copy_spline_attribute_to_mesh(const GSpan src,
+                                          const ResultOffsets &offsets,
+                                          ResultAttributeData &dst_attribute)
+{
+  attribute_math::convert_to_static_type(src.type(), [&](auto dummy) {
+    using T = decltype(dummy);
+    switch (dst_attribute.domain) {
+      case ATTR_DOMAIN_POINT:
+        copy_spline_data_to_mesh(src.typed<T>(), offsets.vert, dst_attribute.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_EDGE:
+        copy_spline_data_to_mesh(src.typed<T>(), offsets.edge, dst_attribute.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_FACE:
+        copy_spline_data_to_mesh(src.typed<T>(), offsets.poly, dst_attribute.data.typed<T>());
+        break;
+      case ATTR_DOMAIN_CORNER:
+        copy_spline_data_to_mesh(src.typed<T>(), offsets.loop, dst_attribute.data.typed<T>());
+        break;
+      default:
+        BLI_assert_unreachable();
+        break;
+    }
+  });
+}
+
+static void copy_spline_domain_attributes_to_mesh(const CurveEval &curve,
+                                                  const CurveEval &profile,
+                                                  const ResultOffsets &offsets,
+                                                  ResultAttributes &attributes)
+{
+  if (!attributes.curve_spline_attributes.is_empty()) {
+    int i = 0;
+    curve.attributes.foreach_attribute(
+        [&](const AttributeIDRef &id, const AttributeMetaData &UNUSED(meta_data)) {
+          if (attributes.curve_spline_attributes[i]) {
+            copy_spline_attribute_to_mesh(*curve.attributes.get_for_read(id),
+                                          offsets,
+                                          *attributes.curve_spline_attributes[i]);
+          }
+          i++;
+          return true;
+        },
+        ATTR_DOMAIN_CURVE);
+  }
+  if (!attributes.profile_spline_attributes.is_empty()) {
+    int i = 0;
+    profile.attributes.foreach_attribute(
+        [&](const AttributeIDRef &id, const AttributeMetaData &UNUSED(meta_data)) {
+          if (attributes.profile_spline_attributes[i]) {
+            copy_spline_attribute_to_mesh(*profile.attributes.get_for_read(id),
+                                          offsets,
+                                          *attributes.profile_spline_attributes[i]);
+          }
+          i++;
+          return true;
+        },
+        ATTR_DOMAIN_CURVE);
+  }
+}
+
+/**
+ * Extrude all splines in the profile curve along the path of every spline in the curve input.
+ * Transfer curve attributes to the mesh.
+ *
+ * \note Normal calculation is by far the slowest part of calculations relating to the result mesh.
+ * Although it would be a sensible decision to use the better topology information available while
+ * generating the mesh to also generate the normals, that work may wasted if the output mesh is
+ * changed anyway in a way that affects the normals. So currently this code uses the safer /
+ * simpler solution of deferring normal calculation to the rest of Blender.
+ */
+Mesh *curve_to_mesh_sweep(const CurveEval &curve, const CurveEval &profile, const bool fill_caps)
+{
+  Span<SplinePtr> profiles = profile.splines();
+  Span<SplinePtr> curves = curve.splines();
+
+  const ResultOffsets offsets = calculate_result_offsets(profiles, curves, fill_caps);
+  if (offsets.vert.last() == 0) {
+    return nullptr;
+  }
+
+  Mesh *mesh = BKE_mesh_new_nomain(
+      offsets.vert.last(), offsets.edge.last(), 0, offsets.loop.last(), offsets.poly.last());
+  BKE_id_material_eval_ensure_default_slot(&mesh->id);
+  mesh->flag |= ME_AUTOSMOOTH;
+  mesh->smoothresh = DEG2RADF(180.0f);
+  BKE_mesh_normals_tag_dirty(mesh);
+
+  ResultAttributes attributes = create_result_attributes(curve, profile, *mesh);
+
+  threading::parallel_for(curves.index_range(), 128, [&](IndexRange curves_range) {
+    for (const int i_spline : curves_range) {
+      const Spline &spline = *curves[i_spline];
+      if (spline.evaluated_points_size() == 0) {
+        continue;
+      }
+      const int spline_start_index = i_spline * profiles.size();
+      threading::parallel_for(profiles.index_range(), 128, [&](IndexRange profiles_range) {
+        for (const int i_profile : profiles_range) {
+          const Spline &profile = *profiles[i_profile];
+          const int i_mesh = spline_start_index + i_profile;
+          ResultInfo info{
+              spline,
+              profile,
+              offsets.vert[i_mesh],
+              offsets.edge[i_mesh],
+              offsets.loop[i_mesh],
+              offsets.poly[i_mesh],
+              spline.evaluated_points_size(),
+              spline.evaluated_edges_size(),
+              profile.evaluated_points_size(),
+              profile.evaluated_edges_size(),
+          };
+
+          spline_extrude_to_mesh_data(info,
+                                      fill_caps,
+                                      {mesh->mvert, mesh->totvert},
+                                      {mesh->medge, mesh->totedge},
+                                      {mesh->mloop, mesh->totloop},
+                                      {mesh->mpoly, mesh->totpoly});
+
+          copy_point_domain_attributes_to_mesh(info, attributes);
+        }
+      });
+    }
+  });
+
+  copy_spline_domain_attributes_to_mesh(curve, profile, offsets, attributes);
+
+  for (OutputAttribute &output_attribute : attributes.attributes) {
+    output_attribute.save();
+  }
+
+  return mesh;
+}
+
+static CurveEval get_curve_single_vert()
+{
+  CurveEval curve;
+  std::unique_ptr<PolySpline> spline = std::make_unique<PolySpline>();
+  spline->add_point(float3(0), 0, 0.0f);
+  curve.add_spline(std::move(spline));
+
+  return curve;
+}
+
+/**
+ * Create a loose-edge mesh based on the evaluated path of the curve's splines.
+ * Transfer curve attributes to the mesh.
+ */
+Mesh *curve_to_wire_mesh(const CurveEval &curve)
+{
+  static const CurveEval vert_curve = get_curve_single_vert();
+  return curve_to_mesh_sweep(curve, vert_curve, false);
+}
+
+}  // namespace blender::bke