翻转精灵动画

Question

stateTime = stateTime + Gdx.graphics.getDeltaTime();

    x_position = x_position + velocity * Gdx.graphics.getDeltaTime();

    if(x_position > Gdx.graphics.getWidth() - 180){
        velocity *= -1;

    }else if(x_position < 0 - 20){
        velocity *= -1;
    }

    Gdx.gl.glClearColor(1, 1, 1, 1);
    Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

    batch.begin();
    batch.draw(mAnimation.getKeyFrame(stateTime, true), x_position, 10, 200, 200);
    batch.end();

我有一个精灵动画，当它到达屏幕的右侧时，它又回到了左侧。如何将精灵动画转到左侧？