@Override
    public void write(JmeExporter ex) throws IOException {
        super.write(ex);
        OutputCapsule oc = ex.getCapsule(this);
        oc.write(blurScale, "blurScale", 1f);
        oc.write(blurThreshold, "blurThreshold", 0.2f);
        oc.write(focusDistance, "focusDistance", 50f);
        oc.write(focusRange, "focusRange", 10f);
        oc.write(debugUnfocus, "debugUnfocus", false); // strange to write this I guess
    }
Turns on/off debugging of the 'unfocus' value that is used to
 mix the convolution filter.  When this is on, the 'unfocus' value
 is rendered as gray scale.  This can be used to more easily visualize
 where in your view the focus is centered and how steep the gradient/cutoff
 is, etcetera.

@param b true to enable debugging, false to disable it (default=false)
jme3-effects/src/main/java/com/jme3/post/filters/DepthOfFieldFilter.java