message: Add isosurface geometry for unstructured volumes
diff: @@ -49,7 +49,15 @@ namespace ospray {
  return;
  }
  - setValue(ospNewVolume("unstructured_volume"));
  + ospVolume = ospNewVolume("unstructured_volume");
  +
  + if (!ospVolume)
  + THROW_SG_ERROR("could not allocate volume");
  +
  + isosurfacesGeometry = ospNewGeometry("isosurfaces");
  + ospSetObject(isosurfacesGeometry, "volume", ospVolume);
  +
  + setValue(ospVolume);
  if (!hasChild("vertices"))
  throw std::runtime_error("#osp:sg UnstructuredVolume -> no 'vertices' array!");
  