JavaScript/特效.html at master · EdwardSYT/JavaScript · GitHub

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<html>


<body style="margin:0; background-color:#33363C; color:#AAB2B8;">
  <canvas id="foo" width="500" height="500" style="cursor:pointer;position:absolute;">
  </canvas>
  <script>
    function drawStuff(c,lineWidth,w,h){
      c.lineWidth = lineWidth
      c.beginPath()
      c.moveTo(Math.random()*w, Math.random()*h)
      c.quadraticCurveTo(
        Math.random()*w,
        Math.random()*h,
        Math.random()*w,
        Math.random()*h)
      c.stroke()
    }
    function drawOtherStuff(c,t){
      c.lineCap = "round"
      c.rotate(Math.sin(t/100)*0.2)
      for (var i=0; i<20; i++){
        var s = Math.sin(t/1000+i*0.8)
        var cs = Math.cos(t/1000+i*0.8)
        c.rotate(Math.sin(t/100)*0.2)
        var y = 100 - 20*s
        c.beginPath()
        var lw = (5-Math.abs(i-5)+1)
        c.lineWidth = lw
        x = 100+cs*20-0.75*(5-Math.abs(i-5)+1)
        c.moveTo(x+lw*0.5,y)
        c.lineTo(x+lw*0.5, y+8*(5-Math.abs(i-5)+1))
        c.stroke()
      }
    }
    function noCrash() {
      var w = document.body.clientWidth
      var h = document.body.clientHeight
      var t = new Date().getTime() / 2
      Foo.ctx.save()
      Foo.ctx.clearRect(0,0,500,500)
      Foo.ctx.translate(250,200)
      Foo.ctx.save()
        Foo.ctx.rotate(Math.PI/4)
        drawOtherStuff(Foo.ctx,t)
      Foo.ctx.restore()
      Foo.ctx.save()
        Foo.ctx.scale(-1,1)
        Foo.ctx.rotate(Math.PI/4)
        drawOtherStuff(Foo.ctx,t)
      Foo.ctx.restore()
      Foo.ctx.restore()
/*      for(var i=0; i<5; i++)
        drawStuff(c,Math.random()*2,100,100)*/
    }
    function clear() {
      Foo.ctx.clearRect(0,0,100,100)
    }
    var e = document.getElementById("foo")
    Foo = e
    Foo.ctx = e.getContext("2d")
    Foo.ctx.strokeStyle = "#AAB2B8"
    e.style.left = document.body.clientWidth/2-250
    e.style.top = document.body.clientHeight/2-250
    e.addEventListener("click",clear,false)
    setInterval(noCrash, 30)
    window.onresize = function(ev){
      e.style.left = document.body.clientWidth/2-250
      e.style.top = document.body.clientHeight/2-250
      noCrash()
    }
  </script>

</body>

</html>