Question

我正在Libgdx开发一款游戏，我正在处理2D框中两个物体之间的碰撞检测。我使用“Contact Listener”来检测碰撞，但是当身体发生碰撞时没有任何反应。

这是我的代码

  public Player(World world,float x,float y,float width)
  {
   this.width=width; //IMP
   height=width*2;
   BodyDef polygon=new BodyDef();
   polygon.type=BodyType.DynamicBody;
   polygon.position.set(x,y); //

   polygon.fixedRotation=true;
   PolygonShape poly =new PolygonShape();
   poly.setAsBox(width/2,height/2); //
  //fixture defn
  polygon.position.set(5,4);
  FixtureDef polyfixture=new FixtureDef();
  polyfixture.shape=poly;

  polyfixture.friction=0.8f;  //
  polyfixture.restitution=0.1f; //
  polyfixture.density=3; //


  //creating actual body
  polybody=world.createBody(polygon);
  polybody.createFixture(polyfixture);


  polysprite=new Sprite(new Texture("img/car.jpg"));

  polysprite.setSize(2, 3); //size of mario
  polysprite.setOrigin(polysprite.getWidth()/2, polysprite.getHeight()/2);
  polybody.setUserData(polysprite);

第二个身体

   BodyDef polygons=new BodyDef();
   polygons.type=BodyType.DynamicBody;

   PolygonShape polys=new PolygonShape();
   polys.setAsBox(2,2);

   FixtureDef polyxfixture=new FixtureDef();
   polyxfixture.shape=polys;
   polyxfixture.friction=0.8f;
   polyxfixture.restitution=0.1f;
   polyxfixture.density=3;
   polybodys=world.createBody(polygons);
   polybodys.createFixture(polyxfixture);
   poly.dispose();    
   }
   @Override
    public void beginContact(Contact contact) {
// TODO Auto-generated method stub

Fixture fixtureA=contact.getFixtureA();
Fixture fixtureB=contact.getFixtureB();

if(fixtureA.getUserData() != null && fixtureA.getUserData().equals("polybody") &&
        fixtureB.getUserData() !=null && fixtureB.getUserData().equals("polybodys")){
    Gdx.app.log("Contact","1");
    System.out.println("its colliding");

}

if(fixtureB.getUserData() !=null && fixtureB.getUserData().equals("polybody") &&
        fixtureA.getUserData() !=null && fixtureA.getUserData().equals("polybodys"))
{
    System.out.println("its colliding");
}
}

我添加了world.setContactListener（播放器）; “玩家”也是上述类别的名称。

这是我检测碰撞的代码。当我运行代码并测试实体之间的碰撞时，没有任何反应。我在控制台中使用“println”语句进行了测试。我不知道这里哪个错了。请帮忙。在此先感谢!!

Answer 1

我认为这个链接应该是你想做的事情的一种方式，也许这不是最好的方法，但它可以帮助另一方面我会尝试调整它来编码你的样品，但如果它起作用，因为不完整，并且有点让我感到困惑

您的代码包含更改：

public Player(World world,float x,float y,float width){

   this.width = width; 
   height     =width*2;

   BodyDef polygon = new BodyDef();
   polygon.type    = BodyType.DynamicBody;

   polygon.position.set(x,y); //<-- you use position one
   polygon.fixedRotation = true;

   PolygonShape poly = new PolygonShape();
                poly.setAsBox(width/2,height/2); 

  //fixture defn

  polygon.position.set(5,4);   //<-- you use position two, twice, 
                               //this overrides the previous consider this

  FixtureDef polyfixture = new FixtureDef();
             polyfixture.shape = poly;

  polyfixture.friction    = 0.8f;  
  polyfixture.restitution = 0.1f; 
  polyfixture.density     = 3; 

  //creating actual body
  polybody = world.createBody(polygon);

  //add.setUserData("YourBody1Name");
  // polybody.createFixture(polyfixture); <-- this original code
  // change for example:
  polybody.createFixture(polyfixture).setUserData("YourBody1"); 

  polysprite = new Sprite(new Texture("img/car.jpg"));

  polysprite.setSize(2, 3); //size of mario
  polysprite.setOrigin(polysprite.getWidth()/2, polysprite.getHeight()/2);

第二个身体＆lt; - 你在玩家类中创造了两个身体，这是你的意图吗？

   BodyDef polygons = new BodyDef();
           polygons.type = BodyType.DynamicBody;

   //you do not use it for poligons position?
   //for example:
   //polygons.position.set(yourPosX,yourPosY); 

   PolygonShape polys = new PolygonShape();
                polys.setAsBox(2,2);

   FixtureDef polyxfixture = new FixtureDef();
              polyxfixture.shape       = polys;
              polyxfixture.friction    = 0.8f;
              polyxfixture.restitution = 0.1f;
              polyxfixture.density     = 3;

   polybodys = world.createBody(polygons);

  //add.setUserData("YourBody2Name");
  // polybodys.createFixture(polyxfixture); <-- this original code
  // change for example:
   polybodys.createFixture(polyxfixture).setUserData("YourBody2"); 

   poly.dispose(); 
   //polys.dispose(); //<-- I do not see this dispose in your code. 

   }

现在在你创建世界的课堂上。复制此代码：

private class CrearContactListener implements ContactListener {

        public CrearContactListener(){

        }
        @Override
        public void preSolve(Contact contact, Manifold oldManifold) {
            // TODO Auto-generated method stub

        }

        @Override
        public void postSolve(Contact contact, ContactImpulse impulse) {
            // TODO Auto-generated method stub

        }

        @Override
        public void endContact(Contact contact) {
            // TODO Auto-generated method stub

        }

        @Override
        public void beginContact(Contact contact) {
            // TODO Auto-generated method stub

            Fixture fixtureA = contact.getFixtureA();
            Fixture fixtureB = contact.getFixtureB();

            if(fixtureA.getUserData() != null 
               && fixtureA.getUserData().equals("YourBody1") 
               && fixtureB.getUserData() != null 
               && fixtureB.getUserData().equals("YourBody2")){

                Gdx.app.log("Contact","1");
            }

            if(fixtureB.getUserData() != null 
               && fixtureB.getUserData().equals("YourBody1")
               && fixtureA.getUserData() != null 
               && fixtureA.getUserData().equals("YourBody2")){

                Gdx.app.log("Contact","2");
            }
        }
}

注意这是一个私有类，你必须把它放在类的合适位置，你不知道在哪里找到一些关于如何在其他类中使用私有类的信息。< / p>

并使用此代码分配ContactListener：

YourWorld.setContactListener(new CrearContactListener());

在身体2看看什么位置，可能是必要的一个。

在此示例中，删除其实现你的班级玩家public void beginContact (Contact contact)的一个原因是我不知道你的玩家类是否实现了ContactListener，或者只是把它放在那里。

我这段代码没有经过测试，但我觉得它可行，考虑到你提到的，另一方面，为我的英语道歉，我希望你理解我。

联系Listener不在Libgdx工作

1 个答案: