message: Skip non-mesh OBJ primitive types to avoid crash.
  OBJ file format supports point, line, mesh, curve, and surface primitive
  types.  We've only ever imported the mesh primitives.  When encountering
  a non-mesh primitive, the mesh.indices.size() is 0.  Skip non-mesh
  primitives to prevent a crash in mesh.createChildData.
diff: @@ -287,6 +287,11 @@ namespace ospray::sg {
  for (auto &shape : objData.shapes) {
  auto numSrcIndices = shape.mesh.indices.size();
  + // Mesh indices.size == 0 indicates a non-mesh primitive
  + // (points, lines, curves and surfaces)
  + if (numSrcIndices == 0)
  + continue;
  +
  std::vector<vec3f> v;
  std::vector<vec4ui> vi;
  std::vector<vec3f> vn;
  