canvas/粒子.html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>粒子</title>
  <style>
    /* html, body {
      margin: 0;
      background: black;
      overflow: hidden;
      width: 100%;
      height: 100%;
    } */
    #canvas {
      background: #000;
    }
  </style>
</head>
<body>
  <canvas id="canvas"></canvas>

  <script>
    const canvas = document.querySelector('#canvas')
    const cvsCtx = canvas.getContext('2d')
    console.log(cvsCtx)

    // 设置宽高
    canvas.width = 500
    canvas.height = 500

    // 绘制整圆
    // cvsCtx.beginPath(); // 开始路径
    // cvsCtx.arc(100, 100, 10, 0, Math.PI * 2, true);
    // cvsCtx.closePath() // 结束路径 
    // cvsCtx.fillStyle = '#fff';
    // cvsCtx.fill();

    // 绘制弧线
    // cvsCtx.beginPath();
    // cvsCtx.arc(100, 100, 50, 0, Math.PI * 1, false);
    // cvsCtx.strokeStyle = '#fff';
    // cvsCtx.stroke();
    // cvsCtx.closePath();

    // 绘制直线
    cvsCtx.beginPath();
    cvsCtx.moveTo(100, 100);
    cvsCtx.lineTo(150, 200);
    cvsCtx.lineWidth = 5;
    cvsCtx.lineCap = 'round';
    cvsCtx.strokeStyle = "#fff";
    cvsCtx.stroke();
  </script>
</body>
</html>