如何降低鸟翅膀和管的速度出现飞扬的鸟游戏的速度？

Question

我是Java编程和Android Studio的新手，我尝试使用我的初学者Java知识来构建Flappy Bird游戏。但是问题是机翼的速度非常快，当我点击屏幕时，电子管的显示速度也很快。如何解决这个问题？我用HTC手机检查了这款游戏。我没有使用模拟器来检查游戏。

SpriteBatch batch;
Texture background;

Texture[] birds;
int flapstate = 0;
float birdY = 0;
float velocity = 0;
int gameState = 0;
float gravity = 2;

Texture toptube;
Texture bottomtube;
float gap = 400;
float maxTubeOffset;
 Random randomGenarator;
 float tubeOffset;

batch = new SpriteBatch();
    background = new Texture("bg.png");

    toptube = new Texture("toptube.png");
    bottomtube = new Texture("bottomtube.png");
    maxTubeOffset = Gdx.graphics.getHeight() / 2 - gap / 2 - 100;
    randomGenarator = new Random();
    birds = new Texture[2];
    birds[0] = new Texture("bird.png");
    birds[1] = new Texture("bird2.png");
    birdY = Gdx.graphics.getHeight() / 2 - birds[0].getHeight() / 2;

batch.begin();
    batch.draw(background, 0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
    if (gameState != 0) {
        if (Gdx.input.justTouched()) {

            velocity = -30;

            tubeOffset = (randomGenarator.nextFloat() - 0.5f) * (Gdx.graphics.getHeight() - gap - 200);



        batch.draw(toptube, Gdx.graphics.getWidth() / 2 - toptube.getWidth() / 2, Gdx.graphics.getHeight() / 2 + gap / 2 + tubeOffset);
        batch.draw(bottomtube, Gdx.graphics.getWidth() / 2 - bottomtube.getWidth() / 2, Gdx.graphics.getHeight() / 2 - gap / 2 - bottomtube.getHeight() + tubeOffset);




        }
        if (birdY > 0 || velocity < 0){
            velocity = velocity + gravity;
            birdY -= velocity;
        }
    }


         else {
            if (Gdx.input.justTouched()) {

                gameState = 1;
            }


        }

        if (flapstate == 0) {
            flapstate = 1;
        } else {

            {
                flapstate = 0;
            }

        }

        batch.draw(birds[flapstate], Gdx.graphics.getWidth() / 2 - birds[flapstate].getWidth() / 2, birdY);
        batch.end();
    }