LibGdx 和 Box2D 与 2d 场景。接地盒不起作用

Question

我读了很多关于“像素米”、视口等的内容。 我想，我在某种程度上已经明白了。 现在已经创建了一个 scene2d 来测试。 但我认为地箱的转换有问题。 香蕉以正常速度飞到地面（接地箱）。然而，接触地面后，香蕉会再次被扔掉（向上）。重力和其他一切都设置正确。对于另一个没有转换 P2M 的项目，它可以工作，但速度非常慢。 如果有人能够准确地解释（可能用代码）如何最好地将 box2D 与 szene2d 结合使用，那就太好了。 我只是无法再进一步了。网上的解释总是很难实施。

P2M.PPM=100； 1 米 = 100 像素（然后会看到 Viewport Box2d 尺寸宽度 10，高度 8）

 public BaseScreen()
{



    assMan.loadAll();
    assMan.manager.finishLoading();

    mainStage = new Stage(viewport=new ExtendViewport(1000,800));
    uiStage = new Stage(viewport=new ExtendViewport(1000,800));

在基本屏幕中调整大小：

 // methods required by Screen interface
public void resize(int width, int height) {
    
    viewport.update(width, height);
}

关卡屏幕：

 public void initialize()
{

    batch = new SpriteBatch();

    TextureAtlas atlas;
    atlas = new TextureAtlas(Gdx.files.internal("sprites.txt"));
    TextureAtlas.AtlasRegion region = atlas.findRegion("banana");
    bananas = atlas.createSprite("banana");
    test = atlas.createSprite("banana");

//camera1 = new OrthographicCamera(); // viewport1 = new ExtendViewport(10, 8, 相机1);

    Box2D.init();
    world = new World(new Vector2(0, -20), true);
    physicsBodies = new PhysicsShapeCache("physics.xml");

    debugRenderer = new Box2DDebugRenderer();

    createGround();
    generateFruit();
    createCollisionListener();



    /* BaseActor space = new BaseActor(0,0, mainStage);
    space.loadTexture("badlogic.jpg");

    space.setSize(1000,800);
    BaseActor.setWorldBounds(space);*/


}

 private void generateFruit() {

    float width = bananas.getWidth() * SCALE;
    float height = bananas.getHeight() * SCALE;

    bananas.setSize(width, height);
    bananas.setOrigin(0, 0);

    name="banana";
    frucht=createBody(name,200 / P2M.PPM,800 /P2M.PPM,0);


}

private Body createBody(String name, float x, float y, float rotation) {
    Body body = physicsBodies.createBody(name, world, SCALE, SCALE);
    body.setUserData("BANANE");
    body.setTransform(x, y, rotation);

    return body;
}

private void drawSprite(String name1, float x, float y, float degrees) {

    Sprite sprite = bananas;//sprites.get(name);
    sprite.setPosition(x, y);
    sprite.setRotation(degrees);
    sprite.draw(batch);
}

private void createGround() {
    if (ground != null) world.destroyBody(ground);

    BodyDef bodyDef = new BodyDef();
    bodyDef.type = BodyDef.BodyType.StaticBody;


    FixtureDef fixtureDef = new FixtureDef();
    fixtureDef.friction = 1;
    PolygonShape shape = new PolygonShape();
    shape.setAsBox(1000   , 0.9f );//0.5f 1000 / P2M.PPM +20

    fixtureDef.shape = shape;

    ground = world.createBody(bodyDef);
    ground.createFixture(fixtureDef);
    ground.setTransform(0 , 0 , 0);
    ground.setUserData("BODEN");




    shape.dispose();
}


 public void update(float dt)
{
    stepWorld();

    int numContacts = world.getContactCount();
    if (numContacts > 0) {
        Gdx.app.log("contact", "start of contact list");
        for (Contact contact : world.getContactList()) {
            Fixture fixtureA = contact.getFixtureA();
            Fixture fixtureB = contact.getFixtureB();

            /*Gdx.app.log("contact", "between " + fixtureA.getBody().getUserData()
                    + " and " + fixtureB.getBody().getUserData());*/

            String a= fixtureA.getBody().getUserData().toString();
            String b= fixtureB.getBody().getUserData().toString();

            Gdx.app.log("contact", "between " + a
                    + " and " + b);

            //Kollidiert Banane mit Boden?******************************************************
            if(a.equals("BANANE") && b.equals("BODEN")){

                Gdx.app.log("TEST", "TEST ERFOLGREICH");
            }

            //Alles andere Auswerten...

            //**********************************************************************************

            //Mit statischen body kollidiert?***************************************************
            if(fixtureA.getBody().getType() == BodyDef.BodyType.StaticBody){
                Gdx.app.log("Contact", "A=STATISCH");

            }
            if(fixtureB.getBody().getType() == BodyDef.BodyType.StaticBody){
                Gdx.app.log("Contact", "B=STATISCH");
            }
            //**********************************************************************************
        }
        Gdx.app.log("contact", "end of contact list");

    }





    batch.begin();

// test.draw(batch);

    Body body = frucht;
    String name1 = "banana";

    Vector2 position = body.getPosition();
    float degrees = (float) Math.toDegrees(body.getAngle());
    drawSprite(name1, position.x * P2M.PPM, position.y * P2M.PPM, degrees);

    Vector2 position1 = ground.getPosition();



    batch.end();

    //        uncomment to show the polygons

// debugRenderer.render(world,camera1.combined);

}




private void stepWorld() {
    float delta = Gdx.graphics.getDeltaTime();
    accumulator += Math.min(delta, 0.25f);



    if (accumulator >= STEP_TIME) {
        accumulator -= STEP_TIME;
        world.step(STEP_TIME, VELOCITY_ITERATIONS, POSITION_ITERATIONS);
    }
}

Answer 1

物体相互弹跳是正常现象。这可以通过使用

FixtureDef

创建主体时设置恢复来控制。但我看到您正在使用某种方式从文件

physics.xml

加载数据，所以我认为您可以控制创建此文件的程序中的恢复。要禁用弹跳，您需要将该值设置为 0。