message: create instances of geoms between xmfs
diff: @@ -51,6 +51,7 @@ namespace ospray::sg {
  // - ...others?
  } current;
  cpp::World world;
  + int unusedGeoms = 0;
  std::vector<cpp::Instance> instances;
  std::stack<affine3f> xfms;
  std::stack<uint32_t> materialIDs;
  @@ -87,7 +88,12 @@ namespace ospray::sg {
  tfns.push(node.valueAs<cpp::TransferFunction>());
  break;
  case NodeType::TRANSFORM:
  + if (unusedGeoms == current.geometries.size())
  xfms.push(xfms.top() * node.valueAs<affine3f>());
  + else {
  + createInstanceFromGroup();
  + xfms.push(xfms.top() * node.valueAs<affine3f>());
  + }
  break;
  case NodeType::LIGHT:
  addLightToWorld(node);
  @@ -155,6 +161,10 @@ namespace ospray::sg {
  inline void RenderScene::createInstanceFromGroup()
  {
  + #if defined(DEBUG)
  + std::cout << "number of geometries : " << current.geometries.size()
  + << std::endl;
  + #endif
  if (current.geometries.empty() && current.volumes.empty())
  return;
  @@ -175,6 +185,9 @@ namespace ospray::sg {
  inst.setParam("xfm", xfms.top());
  inst.commit();
  instances.push_back(inst);
  + #if defined(DEBUG)
  + std::cout << "number of instances : " << instances.size() << std::endl;
  + #endif
  }
  inline void RenderScene::addLightToWorld(Node &node)
  