@Override
    public void write(JmeExporter ex) throws IOException {
        OutputCapsule oc = ex.getCapsule(this);
        oc.write(center, "center", null);
        oc.write(radius, "radius", 0);
    }
Sets the radius of the sphere.

@param radius The new radius.
jme3-core/src/main/java/com/jme3/effect/shapes/EmitterSphereShape.java