direction = direction.set(dl.getDirection());
final double distance = Math.max(radius, _minimumLightDistance);
final Vector3 tmpVec = Vector3.fetchTempInstance();
tmpVec.set(direction);
tmpVec.negateLocal();
tmpVec.multiplyLocal(distance);
tmpVec.addLocal(center);
// temporary location
shadowCam.setLocation(tmpVec);