message: fix fusion problems
diff: @@ -2221,7 +2221,9 @@ namespace RINGMesh {
  auto v_id = geomodel_vertices.geomodel_vertex_id( surface_id,
  ElementLocalVertex( p, v ) );
  ringmesh_assert( v_id != NO_ID );
  - mesh_builder->set_polygon_vertex( cur_polygon, v, v_id );
  + mesh_builder->set_polygon_vertex(
  + PolygonLocalEdge( cur_polygon, v),
  + v_id );
  }
  } else {
  std::vector< index_t > vertices( nb_vertices );
  @@ -2280,7 +2282,9 @@ namespace RINGMesh {
  auto adj = surface.polygon_adjacent_index(
  PolygonLocalEdge( surface_polygon_id, v ) );
  if( adj == NO_ID ) {
  - mesh_builder->set_polygon_adjacent( polygon_id, v, NO_ID );
  + mesh_builder->set_polygon_adjacent(
  + PolygonLocalEdge( polygon_id, v),
  + NO_ID );
  }
  }
  }
  