js里面的碰撞检测。。。。。。。。。

Question

这一段代码里，我想要方块在堆积到顶端以后就会停止下落（希望在原代码上修改）

Answer 1

var cvs=document.getElementById("canvas") var cxt=cvs.getContext("2d") var gravity=0.5 var colors=new Array("#00BFFF","#FFFF00","#FF8C00","#AB82FF","#008B8B") var rects=new Array() var temp=creatRect() window.requestAnimationFrame(drawFrame,cvs) function drawFrame(){ window.requestAnimationFrame(drawFrame,cvs) cxt.clearRect(0,0,cvs.width,cvs.height) temp.vy+=gravity temp.y+=temp.vy if(temp.y+temp.height>cvs.height){ temp.y=cvs.height-temp.height temp=creatRect() } for(var i=0;i<rects.length;i++){ drawRect(rects[i]) } } function creatRect(){ var temp=new Rect() temp.lineWidth=1 temp.color=colors[Math.round(Math.random()*(colors.length-1))] temp.width=Math.round(Math.random()*30+20) temp.height=Math.round(Math.random()*30+20) temp.x=Math.round(Math.random()*(cvs.width-temp.width)) temp.y=0 rects.push(temp) return temp } function drawRect(rect){ if(temp!=rect&&hitTest(temp,rect)){ temp.y=rect.y-temp.height temp=creatRect() } rect.draw(cxt) } function hitTest(rectA,rectB){ return!(rectA.x+rectA.width<rectB.x||rectB.x+rectB.width<rectA.x||rectA.y+rectA.height<rectB.y||rectB.y+rectB.height<rectA.y) }