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HTML

              
                <html lang="en">
<head>
  <meta charset="UTF-8">
  <title>test</title>
  <style>
    body {
      display: flex;
      flex-flow: column wrap;
      justify-content: center;
      align-items: center;
    }

    #c {
      margin-top: 20px;      
    }
  
    input[type=range]::before {content: attr(min);  color: #000; padding-right: 5px;}
    input[type=range]::after { content: attr(max); color: #000; padding-left: 5px;}
  </style>
</head>
<body>
  <canvas id="c">当前浏览器不支持canvas 请升级!</canvas>
  <input type="range" name="range" min="0" max="100" step="1">
</body>

<script>
canvas = document.getElementById("c");
ctx  = canvas.getContext("2d");
oRange = document.getElementsByName("range")[0];

M = Math;
Sin = M.sin;
Cos = M.cos;
Sqrt = M.sqrt;
Pow = M.pow;
PI = M.PI;
Round = M.round;

oW = canvas.width = 300;
oH = canvas.height = 300;

// 线宽
lineWidth = 2

// 大半径
r = (oW / 2);
cR = r - 8*lineWidth;

ctx.beginPath();

ctx.lineWidth = lineWidth;

// 水波动画初始参数
axisLength = 2*r - 16*lineWidth;  // Sin 图形长度
unit = axisLength / 8; // 波浪宽
range = .2 // 浪幅
nowrange = range;  
xoffset = 8*lineWidth; // x 轴偏移量
data = ~~(oRange.value) / 100;   // 数据量
sp = 0; // 周期偏移量
nowdata = 0;
waveupsp = 0.002; // 水波上涨速度

// 圆动画初始参数
arcStack = [];  // 圆栈
bR = r-8*lineWidth;
soffset = -(PI/2); // 圆动画起始位置
circleLock = true; // 起始动画锁

// 获取圆动画轨迹点集
for(var i = soffset; i< soffset + 2*PI; i+=1/(8*PI)) {
  arcStack.push([
    r + bR * Cos(i),
    r + bR * Sin(i)
  ])
}

cStartPoint = arcStack.shift();  // 圆起始点

ctx.strokeStyle = "#1c86d1";
ctx.moveTo(cStartPoint[0],cStartPoint[1])

render();  // 开始渲染

function drawSine () {
  ctx.beginPath();
  ctx.save();
  var Stack = []; // 记录起始点和终点坐标
  for (var i = xoffset; i<=xoffset + axisLength; i+=20/axisLength) {
    var x = sp + (xoffset + i) / unit;
    var y = Sin(x) * nowrange;

    var dx = i;

    var dy = 2*cR*(1-nowdata) + (r - cR) - (unit * y);
    
    ctx.lineTo(dx, dy);
    Stack.push([dx,dy])
  }

  // 获取初始点和结束点
  var startP = Stack[0]
  var endP = Stack[Stack.length - 1]

  ctx.lineTo(xoffset + axisLength,oW);
  ctx.lineTo(xoffset,oW);
  ctx.lineTo(startP[0], startP[1])
  ctx.fillStyle = "#1c86d1";
  ctx.fill()
  ctx.restore();
}

function drawText () {
  ctx.globalCompositeOperation = 'source-over';

  var size = 0.4*cR;
  ctx.font = 'bold ' + size + 'px Microsoft Yahei';

  txt = (nowdata.toFixed(2)*100).toFixed(0) + '%';

  var fonty = r + size/2;
  var fontx = r - size * 0.8;
  ctx.fillStyle = "rgba(06, 85, 128, 0.8)";
  ctx.fillText(txt, fontx, fonty)
}

function render () {
  ctx.clearRect(0,0,oW,oH);

  if (circleLock) {
    if (arcStack.length) {
      var temp = arcStack.shift();
      ctx.lineTo(temp[0],temp[1])
      ctx.stroke();
    } else {
      circleLock = false;
      ctx.lineTo(cStartPoint[0],cStartPoint[1])
      ctx.stroke();
      arcStack = null;

      ctx.globalCompositeOperation = 'destination-over';
      ctx.beginPath();
      ctx.lineWidth = lineWidth;
      ctx.arc(r,r, bR, 0, 2*PI, 1);

      ctx.beginPath();  
      ctx.save();
      ctx.arc(r,r, r-16*lineWidth, 0, 2*PI, 1);
      ctx.restore()
      ctx.clip();

      ctx.fillStyle = "#1c86d1";

      // 初始拖拽控件
      oRange.addEventListener("change", function () {
        data = ~~(oRange.value) / 100;
        console.log("data="+data)
      },0);
    }
  } else {
    // 开始水波动画
    // 控制波幅
    if (data >= 0.85) {
      if (nowrange > range/4) {
        var t = range * 0.01;
        nowrange -= t;   
      }
    } else if (data <= 0.1) {
      if (nowrange < range*1.5) {
        var t = range * 0.01;
        nowrange += t;   
      }
    } else {
      if (nowrange <= range) {
        var t = range * 0.01;
        nowrange += t;   
      }      

      if (nowrange >= range) {
        var t = range * 0.01;
        nowrange -= t;
      }
    }

    if((data - nowdata) > 0) {
      nowdata += waveupsp;      
    }

    if((data - nowdata) < 0){
      nowdata -= waveupsp
    }

    sp += 0.07;
    drawSine();
    drawText();  
  }
  requestAnimationFrame(render)
}
</script>
              
            
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