public void rotateAroundOrigin(float angle, boolean cw) {
        if (cw) {
            angle = -angle;
        }
        float cos = FastMath.cos(angle);
        float sin = FastMath.sin(angle);
        float newX = cos * x - sin * y;
        float newY = sin * x + cos * y;
        x = newX;
        y = newY;
    }
Rotates the vector around (0,0) by the specified angle.

@param angle the rotation angle (in radians)
@param cw true to rotate clockwise, false to rotate counter-clockwise
jme3-core/src/main/java/com/jme3/math/Vector2f.java