Geometry Nodes: Shortest Paths nodes

This adds three new nodes:
* `Shortest Edge Paths`: Actually finds the shortest paths.
* `Edge Paths to Curves`: Converts the paths to separate curves.
  This may generate a quadratic amount of data, making it slow
  for large meshes.
* `Edge Paths to Selection`: Generates an edge selection that
  contains all edges that are part of a path. This can be used
  with the Separate Geometry node to only keep the edges that
  are part of a path. For large meshes, this approach can be
  much faster than the `Edge Paths to Curves` node, because
  less data is created.

Differential Revision: https://developer.blender.org/D15274

2 files changed, 9 insertions, 4 deletions

diff --git a/source/blender/geometry/GEO_mesh_to_curve.hh b/source/blender/geometry/GEO_mesh_to_curve.hh
index f619aaff217..b0f24853dbc 100644
--- a/source/blender/geometry/GEO_mesh_to_curve.hh
+++ b/source/blender/geometry/GEO_mesh_to_curve.hh
@@ -21,4 +21,9 @@ namespace blender::geometry {
  */
 bke::CurvesGeometry mesh_to_curve_convert(const Mesh &mesh, const IndexMask selection);
 
+bke::CurvesGeometry create_curve_from_vert_indices(const Mesh &mesh,
+                                                   Span<int> vert_indices,
+                                                   Span<int> curve_offsets,
+                                                   IndexRange cyclic_curves);
+
 }  // namespace blender::geometry
diff --git a/source/blender/geometry/intern/mesh_to_curve_convert.cc b/source/blender/geometry/intern/mesh_to_curve_convert.cc
index fdacb174462..350dfe73d57 100644
--- a/source/blender/geometry/intern/mesh_to_curve_convert.cc
+++ b/source/blender/geometry/intern/mesh_to_curve_convert.cc
@@ -30,10 +30,10 @@ static void copy_with_map(const VArray<T> &src, Span<int> map, MutableSpan<T> ds
   });
 }
 
-static bke::CurvesGeometry create_curve_from_vert_indices(const Mesh &mesh,
-                                                          const Span<int> vert_indices,
-                                                          const Span<int> curve_offsets,
-                                                          const IndexRange cyclic_curves)
+bke::CurvesGeometry create_curve_from_vert_indices(const Mesh &mesh,
+                                                   const Span<int> vert_indices,
+                                                   const Span<int> curve_offsets,
+                                                   const IndexRange cyclic_curves)
 {
   bke::CurvesGeometry curves(vert_indices.size(), curve_offsets.size());
   curves.offsets_for_write().drop_back(1).copy_from(curve_offsets);