黑客帝国代码雨

news2024/12/23 19:04:32

黑客帝国代码雨奉上,之前一直想写,但一直没抽出时间来,今天把他写了,也算了了装心事

效果图如下
在这里插入图片描述
原理就不讲了,代码写的很清楚而且不长
有不懂的评论区问我就好

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>canvas代码雨</title>
  <style>
    * {
      padding: 0;
      margin: 0;
    }

    canvas {
      display: block;
      width: 100vw;
      height: 100vh;
      background-color: black;
    }
  </style>
</head>

<body>
  <canvas></canvas>
  <script>
    const canvas = document.querySelector('canvas');
    const ctx = canvas.getContext('2d');
    function init() {
      canvas.width = window.innerWidth * devicePixelRatio
      canvas.height = window.innerHeight * devicePixelRatio
    }
    init()
    const fontSize = 10 * devicePixelRatio
    ctx.font = fontSize + 'px Microsoft YaHei'
    const column = Math.floor(canvas.width / fontSize)
    const charIndex = new Array(column).fill(0)
    function draw() {
      ctx.fillStyle = 'rgba(0,0,0,0.1)'
      ctx.fillRect(0, 0, canvas.width, canvas.height)
      ctx.fillStyle = '#0f0'
      ctx.textBaseline = 'top'
      for (let i = 0; i < column; i++) {
        const text = getRandomChat()
        const x = i * fontSize
        const y = charIndex[i] * fontSize
        ctx.fillText(text, x, y)
        if (y > canvas.height && Math.random() > 0.99) {
          charIndex[i] = 0
        } else {
          charIndex[i]++
        }
      }
    }
    function getRandomChat() {
      const str = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
      return str.charAt(Math.floor(Math.random() * str.length))
    }
    draw()
    setInterval(draw, 30)

  </script>
</body>

</html>