Java LibGDX/Box2D车身接收到错误的y坐标

是的，我现在正在使用libGDX/Box2D，我完全被我在学习这套教程时发现的一个bug难住了

在我的游戏中，我创建了一个演员，并将其添加到我的游戏阶段。演员以给定的y坐标放置在屏幕上。游戏只是通过动画循环来模拟跑步

问题是，当我把演员放在游戏舞台上时，它的y坐标不知何故被赋予了错误的y坐标，使用下面的代码片段检索

body.getPosition().y

游戏启动时，演员的y坐标从2.5的正确位置变为3.6的错误位置。然后，参与者从其更新（不正确）的y位置正常操作

我已经调试了我的代码的bejaysus，我看不到任何可能导致这种情况的原因。以前有人见过这种行为吗？这是我不知道的某种Box2D细微差别吗

游戏演员班

public abstract class GameActor extends Actor {

    protected Body body;
    protected UserData userData;
    protected Rectangle screenRectangle;

    public GameActor() {

    }

    public GameActor(Body body) {
        this.body = body;
        this.userData = (UserData) body.getUserData();
        screenRectangle = new Rectangle();
    }

    @Override
    public void act(float delta) {
        super.act(delta);

        if (body.getUserData() != null) {
            updateRectangle();
        } else {
            // This means the world destroyed the body (enemy or runner went out of bounds)
            remove();
        }

    }

    public abstract UserData getUserData();

    private void updateRectangle() {        
        screenRectangle.x = transformToScreen(body.getPosition().x - userData.getWidth() / 2);
        screenRectangle.y = transformToScreen(body.getPosition().y - userData.getHeight() / 2);

        screenRectangle.width = transformToScreen(userData.getWidth());
        screenRectangle.height = transformToScreen(userData.getHeight());
    }

    protected float transformToScreen(float n) {
        return Constants.WORLD_TO_SCREEN * n;
    }
}

public class Runner extends GameActor {

    ...

    @Override
    public void draw(Batch batch, float parentAlpha) {
        super.draw(batch, parentAlpha);

        float x = screenRectangle.x - (screenRectangle.width * 0.1f);
        float y = screenRectangle.y;
        float width = screenRectangle.width * 1.5f;



           stateTime += Gdx.graphics.getRawDeltaTime();
            batch.draw(runningAnimation.getKeyFrame(stateTime, true), x, y - 40, width, screenRectangle.height);
        }
    }
   }

跑步者等级

public abstract class GameActor extends Actor {

    protected Body body;
    protected UserData userData;
    protected Rectangle screenRectangle;

    public GameActor() {

    }

    public GameActor(Body body) {
        this.body = body;
        this.userData = (UserData) body.getUserData();
        screenRectangle = new Rectangle();
    }

    @Override
    public void act(float delta) {
        super.act(delta);

        if (body.getUserData() != null) {
            updateRectangle();
        } else {
            // This means the world destroyed the body (enemy or runner went out of bounds)
            remove();
        }

    }

    public abstract UserData getUserData();

    private void updateRectangle() {        
        screenRectangle.x = transformToScreen(body.getPosition().x - userData.getWidth() / 2);
        screenRectangle.y = transformToScreen(body.getPosition().y - userData.getHeight() / 2);

        screenRectangle.width = transformToScreen(userData.getWidth());
        screenRectangle.height = transformToScreen(userData.getHeight());
    }

    protected float transformToScreen(float n) {
        return Constants.WORLD_TO_SCREEN * n;
    }
}

public class Runner extends GameActor {

    ...

    @Override
    public void draw(Batch batch, float parentAlpha) {
        super.draw(batch, parentAlpha);

        float x = screenRectangle.x - (screenRectangle.width * 0.1f);
        float y = screenRectangle.y;
        float width = screenRectangle.width * 1.5f;



           stateTime += Gdx.graphics.getRawDeltaTime();
            batch.draw(runningAnimation.getKeyFrame(stateTime, true), x, y - 40, width, screenRectangle.height);
        }
    }
   }

---

通过在整个代码中打印body.getPosition（）.y来尝试定位bug的确切位置（就像二分法一样）。@P–risdouad是一个很好的起点。在游戏阶段的第二次和第三次迭代中，通过act（浮动增量）方法，Y位置分两个阶段移动到错误的位置。这看起来像是一个简单的错误，但我们需要一些代码来找出它。是的，没有代码，这将很难。记住调用演员的setBounds方法。