Goal: I am writing a prototype which has as many as 50 (Box2D) colored balls on the screen. I can drag any ball, and what I need to do is test whether the dragging ball has touched a ball of the same color:
My "Balls" are generated as follows:
public static ArrayList<Ball> balls = new ArrayList<Ball>(); //Spawn balls - add them to a list called "balls" public void spawnBalls() { for(int numBalls = 0; numBalls < Constants.MAX_BALLS ; numBalls++) { balls.add(new Ball(world,MathUtils.random(0f,3.5f),MathUtils.random(9.0f,9.5f))); } } They are later rendered as follows:
//Render Balls public void drawBalls(float delta) { for (Ball b : balls) { batch.draw(b.getTexture(), b.getX()-Constants.BALL_SIZE/2, b.getY()-Constants.BALL_SIZE/2, Constants.BALL_SIZE, Constants.BALL_SIZE); b.update(delta); } } I'm using MouseJoints to drag the balls around:
private Vector3 tmp = new Vector3(); private Vector2 tmp2 = new Vector2(); private QueryCallback queryCallback = new QueryCallback() { @Override public boolean reportFixture(Fixture fixture) { if(!fixture.testPoint(tmp.x, tmp.y)) return true; jointDef.bodyB = fixture.getBody(); jointDef.target.set(tmp.x, tmp.y); joint = (MouseJoint) world.createJoint(jointDef); return false; } }; @Override public boolean touchDown(int screenX, int screenY, int pointer, int button) { camera.unproject(tmp.set(screenX, screenY, 0)); world.QueryAABB(queryCallback, tmp.x, tmp.y, tmp.x, tmp.y); return true; } @Override public boolean touchDragged(int screenX, int screenY, int pointer) { if(joint == null) return false; camera.unproject(tmp.set(screenX, screenY, 0)); joint.setTarget(tmp2.set(tmp.x, tmp.y)); return true; } @Override public boolean touchUp(int screenX, int screenY, int pointer, int button) { if(joint == null) return false; world.destroyJoint(joint); joint = null; return true; } Here is my Ball class so far:
public class Ball { private float x, y; World world; public Texture img, red, yellow; Sprite sprite; Body body; public static int color; private Circle boundingCircle; public float angle; public Ball(World world, float x, float y) { //yellow = new Texture("yellow.png"); int c = MathUtils.random(0,5); if(c == 0) { img = new Texture("red.png"); //this.color = 0; this.setColor(0); } else if(c == 1) { img = new Texture("yellow.png"); //this.color = 1; this.setColor(1); } else if(c == 2) { img = new Texture("blue.png"); //this.color = 2; this.setColor(2); } else if(c == 3) { img = new Texture("green.png"); //this.color = 3; this.setColor(3); } else if(c == 4) { img = new Texture("orange.png"); //this.color = 4; this.setColor(4); } else if(c == 5) { img = new Texture("purple.png"); //this.color = 5; this.setColor(5); } //img = new Texture("red.png"); sprite = new Sprite(img); sprite.setPosition(x,y); sprite.setSize(1f,1f); //sprite.setRotation(90f); BodyDef bodyDef = new BodyDef(); bodyDef.type = BodyDef.BodyType.DynamicBody; //bodyDef.position.set((sprite.getX() + sprite.getWidth()) / Constants.PIXELS_TO_METERS, (sprite.getY() + sprite.getHeight()) / Constants.PIXELS_TO_METERS); bodyDef.position.set((sprite.getX() + sprite.getWidth()), (sprite.getY() + sprite.getHeight())); //bodyDef.angularVelocity = 5; body = world.createBody(bodyDef); CircleShape circle = new CircleShape(); circle.setRadius(Constants.BALL_SIZE/2); boundingCircle = new Circle(); boundingCircle.set(x, y, Constants.BALL_SIZE/2); FixtureDef fixtureDef = new FixtureDef(); fixtureDef.shape = circle; fixtureDef.density = 0.9f; fixtureDef.restitution = 0.05f; fixtureDef.friction = 1f; float angle = MathUtils.radiansToDegrees * body.getAngle(); sprite.setRotation(angle); body.createFixture(fixtureDef); circle.dispose(); } } Let's say that I drag a Yellow ball - I would like to be able to determine if I touch another Yellow ball with the one I'm dragging, and if so, destroy the two balls. I'm not sure whether I can achieve this simply using Box2D, or whether I should use Sprite collision instead.
Does anyone have an ideas about how best to implement these kind of tests. So on each ball collision, the balls (dragging & hit) need to return both of their colors, and if they match they can be destroyed.
Any help or direction would be appreciated greatly.
Thanks
James
