Fix T95666: Crash when attempting multires linear subdivide

The crash was happening when the mesh had loose edges.

Loose edges are not part of OpenSubdiv topology and hence should not be
communicated to the refiner. Pass ta boolean flag indicating whether an
edge is loose or not in the mesh foreach routines, which seems to be
the easiest way.

1 files changed, 11 insertions, 9 deletions

diff --git a/source/blender/blenkernel/intern/subdiv_foreach.c b/source/blender/blenkernel/intern/subdiv_foreach.c
index 69bead27fe6..b510a9b3bba 100644
--- a/source/blender/blenkernel/intern/subdiv_foreach.c
+++ b/source/blender/blenkernel/intern/subdiv_foreach.c
@@ -734,7 +734,7 @@ static int subdiv_foreach_edges_row(SubdivForeachTaskContext *ctx,
     const int v1 = vertex_index;
     const int v2 = vertex_index + 1;
     ctx->foreach_context->edge(
-        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, v1, v2);
+        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, false, v1, v2);
     vertex_index += 1;
   }
   return subdiv_edge_index;
@@ -762,7 +762,7 @@ static int subdiv_foreach_edges_column(SubdivForeachTaskContext *ctx,
     const int v1 = vertex_index;
     const int v2 = vertex_index + num_edges_per_row;
     ctx->foreach_context->edge(
-        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, v1, v2);
+        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, false, v1, v2);
     vertex_index += 1;
   }
   return subdiv_edge_index;
@@ -862,7 +862,7 @@ static void subdiv_foreach_edges_all_patches_regular(SubdivForeachTaskContext *c
       const int v1 = (flip) ? (start_edge_vertex + (resolution - i - 3)) : (start_edge_vertex + i);
       const int v2 = side_start_index + side_stride * i;
       ctx->foreach_context->edge(
-          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, v1, v2);
+          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, false, v1, v2);
     }
   }
 }
@@ -926,7 +926,7 @@ static void subdiv_foreach_edges_all_patches_special(SubdivForeachTaskContext *c
       const int v1 = current_patch_vertex_index;
       const int v2 = next_path_vertex_index;
       ctx->foreach_context->edge(
-          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, v1, v2);
+          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, false, v1, v2);
       current_patch_vertex_index += ptex_face_inner_resolution + 1;
       next_path_vertex_index += 1;
     }
@@ -940,7 +940,7 @@ static void subdiv_foreach_edges_all_patches_special(SubdivForeachTaskContext *c
       const int v1 = center_vertex_index;
       const int v2 = current_patch_end_vertex_index;
       ctx->foreach_context->edge(
-          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, v1, v2);
+          ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, false, v1, v2);
     }
   }
   /* Connect inner path of patch to boundary. */
@@ -964,7 +964,7 @@ static void subdiv_foreach_edges_all_patches_special(SubdivForeachTaskContext *c
                                 (start_edge_vertex + i);
         const int v2 = side_start_index + i;
         ctx->foreach_context->edge(
-            ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, v1, v2);
+            ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, false, v1, v2);
       }
     }
     if (ptex_face_resolution >= 3) {
@@ -978,7 +978,7 @@ static void subdiv_foreach_edges_all_patches_special(SubdivForeachTaskContext *c
                                 (start_edge_vertex + i);
         const int v2 = side_start_index + (ptex_face_inner_resolution + 1) * i;
         ctx->foreach_context->edge(
-            ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, v1, v2);
+            ctx->foreach_context, tls, ORIGINDEX_NONE, subdiv_edge_index, false, v1, v2);
       }
     }
     prev_coarse_loop = coarse_loop;
@@ -1015,6 +1015,8 @@ static void subdiv_foreach_boundary_edges(SubdivForeachTaskContext *ctx,
   const int resolution = ctx->settings->resolution;
   const int num_subdiv_vertices_per_coarse_edge = resolution - 2;
   const int num_subdiv_edges_per_coarse_edge = resolution - 1;
+  const bool is_loose = !BLI_BITMAP_TEST_BOOL(ctx->coarse_edges_used_map, coarse_edge_index);
+
   int subdiv_edge_index = ctx->edge_boundary_offset +
                           coarse_edge_index * num_subdiv_edges_per_coarse_edge;
   int last_vertex_index = ctx->vertices_corner_offset + coarse_edge->v1;
@@ -1023,13 +1025,13 @@ static void subdiv_foreach_boundary_edges(SubdivForeachTaskContext *ctx,
     const int v2 = ctx->vertices_edge_offset +
                    coarse_edge_index * num_subdiv_vertices_per_coarse_edge + i;
     ctx->foreach_context->edge(
-        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, v1, v2);
+        ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, is_loose, v1, v2);
     last_vertex_index = v2;
   }
   const int v1 = last_vertex_index;
   const int v2 = ctx->vertices_corner_offset + coarse_edge->v2;
   ctx->foreach_context->edge(
-      ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, v1, v2);
+      ctx->foreach_context, tls, coarse_edge_index, subdiv_edge_index, is_loose, v1, v2);
 }
 
 /** \} */