docs: public void rotate(Quaternion rotation, Point3D pivot1) {
  		if (pivot1==null) {
  			rotate(rotation);
  		} else {
  			assert(pivot1!=null);
  
  			Transform3D tr = new Transform3D();
  			tr.setRotation(rotation);
  			Vector3f v = new Vector3f();
  
  			v.sub(this.getP1(), pivot1);
  			tr.transform(v);
  			this.getP1().add(pivot1, v);
  
  			v.sub(this.getP2(), pivot1);
  			tr.transform(v);
  			this.getP2().add(pivot1, v);
  
  			v.sub(this.getP3(), pivot1);
  			tr.transform(v);
  			this.getP3().add(pivot1, v);
  
  			clearBufferedData();
  		}
  	}