@Override
    public void getRandomPointAndNormal(Vector3f store, Vector3f normal) {
        this.getRandomPoint(store);
        normal.set(store).subtractLocal(center).normalizeLocal();
    }
For a sphere shape, the normal is not well-defined for points within the volume.
This implementation simply calls {@link #getRandomPoint(Vector3f)} and does not modify the provided normal.

@param store  The {@link Vector3f} to store the generated point in.
@param normal The {@link Vector3f} to store the generated normal in (unused).
jme3-core/src/main/java/com/jme3/effect/shapes/EmitterSphereShape.java