1 files changed, 62 insertions, 7 deletions

diff --git a/source/blender/blenkernel/BKE_mesh_sample.hh b/source/blender/blenkernel/BKE_mesh_sample.hh
index a942f3bb7ed..356709d8942 100644
--- a/source/blender/blenkernel/BKE_mesh_sample.hh
+++ b/source/blender/blenkernel/BKE_mesh_sample.hh
@@ -6,17 +6,21 @@
  * \ingroup bke
  */
 
+#include "BLI_function_ref.hh"
 #include "BLI_generic_virtual_array.hh"
 #include "BLI_math_vec_types.hh"
 
+#include "DNA_meshdata_types.h"
+
 #include "BKE_attribute.h"
+#include "BKE_attribute.hh"
 
 struct Mesh;
+struct BVHTreeFromMesh;
 
-namespace blender::bke {
-struct ReadAttributeLookup;
-class OutputAttribute;
-}  // namespace blender::bke
+namespace blender {
+class RandomNumberGenerator;
+}
 
 namespace blender::bke::mesh_surface_sample {
 
@@ -69,12 +73,12 @@ class MeshAttributeInterpolator {
                             const Span<int> looptri_indices);
 
   void sample_data(const GVArray &src,
-                   AttributeDomain domain,
+                   eAttrDomain domain,
                    eAttributeMapMode mode,
                    const GMutableSpan dst);
 
-  void sample_attribute(const ReadAttributeLookup &src_attribute,
-                        OutputAttribute &dst_attribute,
+  void sample_attribute(const GAttributeReader &src_attribute,
+                        GSpanAttributeWriter &dst_attribute,
                         eAttributeMapMode mode);
 
  protected:
@@ -82,4 +86,55 @@ class MeshAttributeInterpolator {
   Span<float3> ensure_nearest_weights();
 };
 
+/**
+ * Find randomly distributed points on the surface of a mesh within a 3D sphere. This does not
+ * sample an exact number of points because it comes with extra overhead to avoid bias that is only
+ * required in some cases. If an exact number of points is required, that has to be implemented at
+ * a higher level.
+ *
+ * \param approximate_density: Roughly the number of points per unit of area.
+ * \return The number of added points.
+ */
+int sample_surface_points_spherical(RandomNumberGenerator &rng,
+                                    const Mesh &mesh,
+                                    Span<int> looptri_indices_to_sample,
+                                    const float3 &sample_pos,
+                                    float sample_radius,
+                                    float approximate_density,
+                                    Vector<float3> &r_bary_coords,
+                                    Vector<int> &r_looptri_indices,
+                                    Vector<float3> &r_positions);
+
+/**
+ * Find randomly distributed points on the surface of a mesh within a circle that is projected on
+ * the mesh. This does not result in an exact number of points because that would come with extra
+ * overhead and is not always possible. If an exact number of points is required, that has to be
+ * implemented at a higher level.
+ *
+ * \param region_position_to_ray: Function that converts a 2D position into a 3D ray that is used
+ *   to find positions on the mesh.
+ * \param mesh_bvhtree: BVH tree of the triangles in the mesh. Passed in so that it does not have
+ *   to be retrieved again.
+ * \param tries_num: Number of 2d positions that are sampled. The maximum
+ *   number of new samples.
+ * \return The number of added points.
+ */
+int sample_surface_points_projected(
+    RandomNumberGenerator &rng,
+    const Mesh &mesh,
+    BVHTreeFromMesh &mesh_bvhtree,
+    const float2 &sample_pos_re,
+    float sample_radius_re,
+    FunctionRef<void(const float2 &pos_re, float3 &r_start, float3 &r_end)> region_position_to_ray,
+    bool front_face_only,
+    int tries_num,
+    int max_points,
+    Vector<float3> &r_bary_coords,
+    Vector<int> &r_looptri_indices,
+    Vector<float3> &r_positions);
+
+float3 compute_bary_coord_in_triangle(const Mesh &mesh,
+                                      const MLoopTri &looptri,
+                                      const float3 &position);
+
 }  // namespace blender::bke::mesh_surface_sample