@Override
    public void write(JmeExporter ex) throws IOException {
        OutputCapsule oc = ex.getCapsule(this);
        oc.write(size, "patchSize", 32);
        oc.write(lodMultiplier, "lodMultiplier", 32);
    }
Calculates the LOD of the terrain based on its distance from the
cameras. Taking the minimum distance from all cameras.

@author bowens
jme3-terrain/src/main/java/com/jme3/terrain/geomipmap/lodcalc/DistanceLodCalculator.java