public int hashCode() {
        int hash = 37;
        hash = 37 * hash + Float.floatToIntBits(x);
        hash = 37 * hash + Float.floatToIntBits(y);
        hash = 37 * hash + Float.floatToIntBits(z);
        hash = 37 * hash + Float.floatToIntBits(w);
        return hash;

    }