message: Initialize Renderable:bounds as empty
diff: @@ -425,7 +425,7 @@ namespace ospray {
  //! a Node with bounds and a render operation
  struct OSPSG_INTERFACE Renderable : public Node
  {
  - Renderable() { createChild("bounds", "box3f"); }
  + Renderable() { createChild("bounds", "box3f", box3f(empty)); }
  virtual ~Renderable() = default;
  virtual std::string toString() const override
  