Shifter: Auto Fit Guide: update accel #620

Author: miquelcampos

python_src/include/rgp_accel.h

@@ -536,6 +536,7 @@ RecordMirrorResult record_mirror(
     const std::vector<int>& face_vert_counts,
     const std::vector<int>& face_vert_indices,
     int num_verts,
+    const std::vector<double>& mirror_positions,
     ProgressCB progress_cb = nullptr);
 
 /**

python_src/src/bindings.cpp

@@ -108,6 +108,7 @@ PYBIND11_MODULE(_rgp_accel_cpp, m) {
            const std::vector<int>& face_vert_counts,
            const std::vector<int>& face_vert_indices,
            int num_verts,
+           const std::vector<double>& mirror_positions,
            py::object progress_cb) -> py::dict
         {
             auto cb = wrap_progress(progress_cb);
@@ -121,7 +122,7 @@ PYBIND11_MODULE(_rgp_accel_cpp, m) {
                     sample_count,
                     points, face_normals,
                     face_vert_counts, face_vert_indices,
-                    num_verts, cb);
+                    num_verts, mirror_positions, cb);
             }
 
             py::dict d;
@@ -137,10 +138,14 @@ PYBIND11_MODULE(_rgp_accel_cpp, m) {
         py::arg("face_vert_counts"),
         py::arg("face_vert_indices"),
         py::arg("num_verts"),
+        py::arg("mirror_positions"),
         py::arg("progress_cb") = py::none(),
         "Record mirror side for all guides (batch).\n\n"
         "Performs BFS flood-fill + reference matrix construction for\n"
-        "each mirror position. Returns dict with:\n"
+        "each mirror position. Uses mirror_positions (reflected guide\n"
+        "world positions) as the distance reference for vertex sorting,\n"
+        "matching the Python path behavior.\n\n"
+        "Returns dict with:\n"
         "  vert_ids: flat list of guide_count * sample_count ints\n"
         "  ref_matrices: flat list of guide_count * 16 doubles"
     );

python_src/src/rgp_accel.cpp

@@ -391,6 +391,7 @@ RecordMirrorResult record_mirror(
     const std::vector<int>& face_vert_counts,
     const std::vector<int>& face_vert_indices,
     int num_verts,
+    const std::vector<double>& mirror_positions,
     ProgressCB progress_cb)
 {
     int guide_count = static_cast<int>(seed_offsets.size()) - 1;
@@ -419,20 +420,12 @@ RecordMirrorResult record_mirror(
             seed_vert_ids.begin() + seed_start,
             seed_vert_ids.begin() + seed_end);
 
-        // We need a reference position for distance sorting.
-        // Use the centroid of the seed vertices as the reference.
-        Vec3 ref_pos;
-        for (int s : seeds) {
-            ref_pos.x += points[s * 3];
-            ref_pos.y += points[s * 3 + 1];
-            ref_pos.z += points[s * 3 + 2];
-        }
-        if (!seeds.empty()) {
-            double inv = 1.0 / static_cast<double>(seeds.size());
-            ref_pos.x *= inv;
-            ref_pos.y *= inv;
-            ref_pos.z *= inv;
-        }
+        // Use the reflected guide position for distance sorting.
+        // This matches the Python path which passes the exact mirror
+        // world-space position to getClosestNVerticesFromTransform().
+        Vec3 ref_pos(mirror_positions[g * 3],
+                     mirror_positions[g * 3 + 1],
+                     mirror_positions[g * 3 + 2]);
 
         // BFS flood-fill
         std::vector<int> closest = find_n_closest_vertices(

release/scripts/mgear/shifter/relative_guide_placement.py

@@ -600,6 +600,8 @@ def _yield_guide_relative_accel(shape_name, mesh_name, guideOrder,
         shape_name, p_mirror_positions)
 
     # 6. C++ record_mirror: BFS + ref matrices for mirror side
+    #    Pass mirror_positions so C++ uses the reflected guide position
+    #    (not seed polygon centroid) as the distance reference for BFS.
     mirror_result = record_mirror(
         mr_seed_vert_ids,
         mr_seed_offsets,
@@ -609,6 +611,7 @@ def _yield_guide_relative_accel(shape_name, mesh_name, guideOrder,
         face_vert_counts,
         face_vert_indices,
         num_verts,
+        p_mirror_positions,
     )
 
     mr_vert_ids = mirror_result["vert_ids"]