public Vector4f subtractLocal(float subtractX, float subtractY, float subtractZ, float subtractW) {
        x -= subtractX;
        y -= subtractY;
        z -= subtractZ;
        w -= subtractW;
        return this;
    }
<code>subtractLocal</code> subtracts the provided values from this vector
internally, and returns a handle to this vector for easy chaining of
calls.

@param subtractX
           the x value to subtract.
@param subtractY
           the y value to subtract.
@param subtractZ
           the z value to subtract.
@param subtractW
           the w value to subtract.
@return this
jme3-core/src/main/java/com/jme3/math/Vector4f.java