因此,我使用Chipmunk JS演示来了解它的工作原理(请参见https://github.com/josephg/Chipmunk-js)。简单的演示一开始很好,但后来东西开始疯狂跳动,我一直在努力解决这个问题,但迄今为止没有成功。
var radToDeg = 180 / Math.PI;
function PlayState() {
this.blocks = [];
this.setup = function() {
space.iterations = 100;
space.gravity = new cp.Vect(0, 150);
space.game = this;
this.ground = space.addShape(new cp.SegmentShape(space.staticBody, new cp.v(0, 480), new cp.v(640, 480), 0));
this.ground.setElasticity(0);
this.ground.setFriction(1);
};
this.update = function() {
space.step(this.dt);
for (var i = 0; i < this.blocks.length; i++) {
var block = this.blocks[i];
block.sprite.x = block.body.p.x;
block.sprite.y = block.body.p.y;
block.sprite.angle = block.body.a * radToDeg;
}
if (isMouseDown("left")) {
if (this.canAddBlock) {
this.canAddBlock = false;
this.addBlock(mouseX, mouseY);
}
} else {
this.canAddBlock = true;
}
};
this.draw = function() {
clearCanvas();
for (var i = 0; i < this.blocks.length; i++) {
this.blocks[i].sprite.draw();
}
// this.ground.sprite.draw();
};
this.addBlock = function(x, y) {
width = 64;
height = 64;
var newBlock = new Block(x, y, width, height);
newBlock.body = space.addBody(new cp.Body(1, cp.momentForBox(1, width, height)));
newBlock.body.setPos(new cp.v(x, y));
newBlock.shape = space.addShape(new cp.BoxShape(newBlock.body, width, height));
newBlock.shape.setElasticity(0);
newBlock.shape.setFriction(1);
this.blocks.push(newBlock);
};
}
desiredFPS = 60;
switchState(new PlayState());
源代码很简单明了,但我对创建地面的方式有些怀疑,因为我无法确定它实际上处于什么位置。不过方块似乎能够找到它并与其碰撞。
另一个源文件是一个小的块类,帮助我组织事物:
Block = (function() {
function constructor(x, y, width, height) {
this.sprite = new Sprite("res/block.png", x, y);
this.width = width;
this.height = height;
}
constructor.prototype = {
update: function() {
}
};
return constructor;
})();