}
final double dist = tracer.getTotalTraveled();
// look at where we are and switch to the next cliplevel if needed
final Vector3 loc = new Vector3(_workRay.getDirection()).multiplyLocal(dist).addLocal(_workRay.getOrigin());
final int newIndex = findClipIndex(loc.subtract(_workEyePos, null));
// simple test to see if our next level at least has SOME data. XXX: could look to the tile level.
if (newIndex != index && _clipmapLevels.get(index).isReady()) {
_workRay.setOrigin(loc);
index = newIndex;
tracer = _tracers.get(index);