2015-02-11 22 views
0

UPDATEJBox2D + Slick2D - 不衝突

我有一個提示。這是因爲JBox2D屏幕的中心是(0, 0)。這太奇怪了,因爲xy不是從-11,它取決於屏幕尺寸。
這意味着我從互聯網複製的Util類(每個人都共享此代碼)不是最新的。我仍然需要幫助,因爲我找不到任何'算法'具有縱橫比+屏幕尺寸依賴性。


BASE問題

因爲我已經加入了「slick2D到jbox2D位置」,反之亦然(這就像在屏幕上的位置=屏幕/ 100位置JBox),我不明白一個好的結果。

public class Util { 
    private static final float SCALE = 0.01f; // 1/100 pixels 
    public static float toPosX(float posX) { return (posX * SCALE); } 
    public static float toPosY(float posY) { return (-posY * SCALE); } 
    public static float toScreenX(float posX) { return (posX/SCALE); } 
    public static float toScreenY(float posY) { return (-posY/SCALE); } 
} 

Square.java:

public class Square { 
    private Body body; 
    private Rectangle rectangle; 

    Square(World world, BodyType type, Vec2 pos, Vec2 size) { 
     float x = Util.toPosX(pos.x); 
     float y = Util.toPosY(pos.y); 
     float sx = Util.toPosX(size.x); 
     float sy = Util.toPosY(size.y); 

     //body definition 
     BodyDef bd = new BodyDef(); 
     bd.position.set(x, y); 
     bd.type = type; 

     //define shape of the body. 
     PolygonShape cs = new PolygonShape(); 
     cs.setAsBox(sx, sy); 

     //define fixture of the body. 
     FixtureDef fd = new FixtureDef(); 
     fd.shape = cs; 
     fd.density = 1f; 
     fd.friction = 0.3f; 
     fd.restitution = 1.0f; 

     //create the body and add fixture to it 
     body = world.createBody(bd); 
     body.createFixture(fd); 

     rectangle = new Rectangle(0, 0, size.x, size.y); 
     rectangle.setLocation(pos.x, pos.y); 
    } 

    public Body getBody() { return this.body; } 
    public Rectangle getRectangle() { return this.rectangle; } 
} 

最後我的顯示類:下面

截圖我的代碼解釋

public class DisplayManager extends BasicGame { 

    private GameManager gameManager; 
    private Body b1, b2; 
    private Rectangle r1, r2; 
    private World world; 

    public DisplayManager(GameManager game) { 
     super("Title"); 
     this.gameManager = game; 
    } 

    @Override 
    public void init(GameContainer container) throws SlickException { 
     this.gameManager.initPlayersSprites(); 

     world = new World(new Vec2(0, -10)); 
     Square s1, s2; 
     s1 = new Square(world, BodyType.STATIC, new Vec2(10, 800), new Vec2(1900, 30)); 
     b1 = s1.getBody(); 
     r1 = s1.getRectangle(); 
     s2 = new Square(world, BodyType.DYNAMIC, new Vec2(945, 200), new Vec2(30, 30)); 
     b2 = s2.getBody(); 
     r2 = s2.getRectangle(); 
    } 

    public void render(GameContainer container, Graphics g) throws SlickException { 
     float step = 1.0f/600.0f; 
     world.step(step, 6, 2); 
     r1.setLocation(Util.toScreenX(b1.getPosition().x), Util.toScreenY(b1.getPosition().y)); 
     r2.setLocation(Util.toScreenX(b2.getPosition().x), Util.toScreenY(b2.getPosition().y)); 
     g.draw(r1); 
     g.draw(r2); 
    } 
} 

下面是結果: 第一幀: http://i.stack.imgur.com/WgQPK.png

一些畫面之後: http://i.stack.imgur.com/a1XyL.png

(地上不動了,它只是一個截圖從我手裏拿着)

換句話說,立方體落下像永遠。我調試了立方體的位置,它不停下來。

使用Slick2D DebugDraw不會有幫助,因爲無論如何立方體都會穿過地面。
請注意,在JBox2D,它與像素測量(這是不準確的,但碰撞運作良好)

回答

0

這是因爲負尺寸。 (toPoxY反轉y pos)