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我正在写一个摆动钟摆的 GameActivity（在 AndEngine 中）。

在应用CollisionHandler时，这会产生一系列的碰撞事件而不是一个？？实际上，我希望它只在精灵碰撞时执行一次。

我的情况：当与movingBall相撞时mLeftWall，它叫5 timesof onCollision()；这是不正常的，我预计只有一次。

我应该ContactListener改用并注册PhysicsWorld吗？这是我的代码：

MyGameActivity.java：

/** List of objects to check collision of any animating objects. E.g: walls  */
private ArrayList<IShape> mCollidingTargetList = new ArrayList<IShape>();

/** user-defined collision handler */
PendulumCollisionCallback collideActionCallback = new PendulumCollisionCallback();

@Override
public Scene onCreateScene() 
{
    final Scene scene = super.onCreateScene();

    final VertexBufferObjectManager vertexBufferObjectManager = this.getVertexBufferObjectManager();

    //Create walls
    mWallLeft = new Rectangle(0, 0, 2, mCameraHeight, vertexBufferObjectManager);
    mWallRight = new Rectangle(mCameraWidth - 2, 0, 2, mCameraHeight, vertexBufferObjectManager);
    PhysicsFactory.createBoxBody(mPhyscisWorld, mWallLeft, BodyType.StaticBody, mWallFixtureDef);
    PhysicsFactory.createBoxBody(mPhyscisWorld, mWallRight, BodyType.StaticBody, mWallFixtureDef);
    scene.attachChild(mWallLeft);
    scene.attachChild(mWallRight);

    //Create movingBall - the pendulum ball
    final AnimatedSprite movingBall = new AnimatedSprite(mCenterX, mCenterY, this.mCircleFaceTextureRegion, this.getVertexBufferObjectManager());
    final Body ballBody = PhysicsFactory.createCircleBody(this.mPhysicsWorld, movingBall, BodyType.DynamicBody, mObjectFixtureDef);
    movingBall.setUserData(ballBody); // for getting the body attached with UI

    //..... Stuff to create anchorBody and RevoluteJoint with the movingBall

    //list of bodies where sprites collide
    this.mCollidingTargetList.add(mWallLeft);
    this.mCollidingTargetList.add(mWallRight);

    //Manage user-defined collision handler: movingBall collides with walls
    CollisionHandler pendulumCollideHandler = new CollisionHandler(collideActionCallback, movingBall, mCollidingTargetList);
    scene.registerUpdateHandler(pendulumCollideHandler);

    return scene;
}

PendulumCollisionCallback.java:

public class PendulumCollisionCallback implements ICollisionCallback
{
    public PendulumCollisionCallback()
    { }

    /**
     * @param animatedShape
     *      Entity to check collision with other targets
     * @param pTargetShape
     *      Target to check the collision
     * @return <code>true</code> to proceed, <code>false</code> to stop further collosion-checks.
     */
    @Override
    public boolean onCollision(IShape animatedShape, IShape pTargetShape) 
    {
        String pendulPos = String.format("Pendul:x=%f, y=%f", animatedShape.getX(), animatedShape.getY());      
        Log.d("COLLIDE", pendulPos);
        return false;
    }
}
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1 回答 1

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我发现了这个问题。这是因为分离Physics Handler和场景的UpdateHandler工作顺序。

虽然PhysicsWorld仍在控制身体碰撞，但身体仍在向前移动几帧 => 以便 UI 精灵（与此身体相连）的位置与碰撞对象相交。在这些帧期间，updateHandler产生碰撞事件CallbackHandler。

解决方案是添加布尔标志的一种棘手方法，该标志在第一次碰撞时设置并在完成碰撞时取消设置（尽管这不是很好）。

P/S：我的帧率观察形式FPSLogger是~88,9 FPS。

于 2012-09-05T03:53:17.787 回答