public float distanceSquared(Vector4f v) {
        double dx = x - v.x;
        double dy = y - v.y;
        double dz = z - v.z;
        double dw = w - v.w;
        return (float) (dx * dx + dy * dy + dz * dz + dw * dw);
    }
<code>distanceSquared</code> calculates the distance squared between
this vector and vector v.

@param v the second vector to determine the distance squared.
@return the distance squared between the two vectors.
jme3-core/src/main/java/com/jme3/math/Vector4f.java