/**
* Calculates the distance from a spatial to the camera. Distance is a squared distance.
*
* @param spat Spatial to check distance.
* @return Distance from Spatial to current context's camera.
*/
protected double distanceToCam(final Spatial spat) {
if (spat._queueDistance != Double.NEGATIVE_INFINITY) {
return spat._queueDistance;
}
final Camera cam = Camera.getCurrentCamera();
if (spat.getWorldBound() != null && Vector3.isValid(spat.getWorldBound().getCenter())) {
spat._queueDistance = spat.getWorldBound().distanceToEdge(cam.getLocation());
} else {
final ReadOnlyVector3 spatPosition = spat.getWorldTranslation();
if (!Vector3.isValid(spatPosition)) {
spat._queueDistance = Double.POSITIVE_INFINITY;
} else {
spat._queueDistance = cam.getLocation().distance(spatPosition);
}
}
return spat._queueDistance;
}
