message: instance bounds calculations over empty model was creating NANS in bound calculation
diff: @@ -61,6 +61,7 @@ namespace ospray {
  " have a valid bounding box. epsilons for"
  " ray offsets may be wrong");
  }
  + else {
  const vec3f v000(b.lower.x,b.lower.y,b.lower.z);
  const vec3f v001(b.upper.x,b.lower.y,b.lower.z);
  const vec3f v010(b.lower.x,b.upper.y,b.lower.z);
  @@ -79,6 +80,7 @@ namespace ospray {
  bounds.extend(xfmPoint(xfm,v101));
  bounds.extend(xfmPoint(xfm,v110));
  bounds.extend(xfmPoint(xfm,v111));
  + }
  rtcSetGeometryTransform(embreeGeom,0,RTC_FORMAT_FLOAT3X4_COLUMN_MAJOR,&xfm);
  rtcCommitGeometry(embreeGeom);
  