Bing Maps

<!--
  示例：Bing Maps 瓦片与 quadkey 寻址
  要点：quadkey 由 z/x/y 逐位拼出，切换影像集时清缓存并刷新数据源
  依赖：OpenLayers 10.3.1 · jsDelivr CDN
-->
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta name="robots" content="noindex,follow">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Bing Maps 瓦片与 quadkey 寻址</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@10.3.1/ol.css">
<style>
  html,body{height:100%;margin:0}
  body{display:flex;flex-direction:column;overflow:hidden;
       font:13px/1.6 -apple-system,"Segoe UI","PingFang SC",sans-serif;color:#16181d}
  .bar{flex:0 0 auto;padding:8px 12px;background:#f6f7f9;border-bottom:1px solid #e3e6ea;
       display:flex;gap:12px;align-items:center;font-size:12px;color:#58606e;flex-wrap:wrap}
  .bar label{display:flex;gap:5px;align-items:center;cursor:pointer}
  .bar b{color:#16181d;font-weight:600}
  #map{flex:1 1 auto;min-height:0;background:#eef0f3}
</style>
</head>
<body>
<div class="bar">
  <label><input type="radio" name="set" value="road" checked> 道路</label>
  <label><input type="radio" name="set" value="aerial"> 影像</label>
  <span>中心瓦片 quadkey：<b id="quad">—</b></span>
</div>
<div id="map"></div>
<script src="https://cdn.jsdelivr.net/npm/ol@10.3.1/dist/ol.js"></script>
<script>
(function () {
  'use strict';
  if (!window.ol) {
    document.getElementById('map').textContent = 'OpenLayers 加载失败，请检查 cdn.jsdelivr.net 是否可访问';
    return;
  }

  var palette = {
    road:   { bg: '#f2efe9', line: '#e0d9cc', text: '#5b5647' },
    aerial: { bg: '#20301f', line: '#2f4630', text: '#cfd8c6' }
  };
  var imagerySet = 'road';
  var cache = {};

  /* Bing 用 quadkey 定位瓦片：从最高位开始，按 x、y 的二进制位拼出 0~3 的字符 */
  function quadkey(z, x, y) {
    var key = '';
    for (var i = z - 1; i >= 0; i--) {
      var digit = ((y >> i) & 1) * 2 + ((x >> i) & 1);
      key += digit;
    }
    return key || '0';
  }

  function tileURL(z, x, y) {
    var key = imagerySet + '/' + z + '/' + x + '/' + y;
    if (cache[key]) return cache[key];

    var p = palette[imagerySet];
    var c = document.createElement('canvas');
    c.width = c.height = 256;
    var ctx = c.getContext('2d');

    ctx.fillStyle = p.bg;
    ctx.fillRect(0, 0, 256, 256);

    /* 用 quadkey 数值做伪随机，让相邻瓦片纹理连续可辨 */
    var seed = 0;
    var q = quadkey(z, x, y);
    for (var i = 0; i < q.length; i++) seed = (seed * 31 + q.charCodeAt(i)) % 1000;

    ctx.fillStyle = p.line;
    for (var k = 0; k < 6; k++) {
      var pos = ((seed + k * 137) % 220) + 18;
      ctx.fillRect(0, pos, 256, 3);
      ctx.fillRect(pos, 0, 3, 256);
    }

    ctx.fillStyle = p.text;
    ctx.font = '600 11px monospace';
    ctx.fillText(q, 8, 20);

    cache[key] = c.toDataURL('image/png');
    return cache[key];
  }

  var source = new ol.source.XYZ({
    maxZoom: 19,
    tileSize: 256,
    attributions: '自造瓦片 · quadkey 寻址对齐 Bing Maps',
    tileUrlFunction: function (tileCoord) {
      return tileURL(tileCoord[0], tileCoord[1], tileCoord[2]);
    }
  });

  var map = new ol.Map({
    target: 'map',
    layers: [new ol.layer.Tile({ source: new ol.source.XYZ({url: 'https://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer/tile/{z}/{y}/{x}', attributions: 'Tiles © Esri'}) }),
             new ol.layer.Tile({ source: source, opacity: 0.92 })],
    view: new ol.View({
      center: ol.proj.fromLonLat([116.391263, 39.907359]),
      zoom: 10,
      maxZoom: 19
    }),
    controls: ol.control.defaults.defaults({ rotate: false })
  });

  function reportQuad() {
    var z = Math.round(map.getView().getZoom());
    var tc = source.getTileGrid().getTileCoordForCoordAndZ(map.getView().getCenter(), z);
    document.getElementById('quad').textContent = tc ? quadkey(tc[0], tc[1], tc[2]) : '—';
  }

  document.querySelectorAll('input[name=set]').forEach(function (el) {
    el.addEventListener('change', function () {
      imagerySet = this.value;
      source.refresh();          /* 影像集变了，已缓存的瓦片全部作废 */
      reportQuad();
    });
  });

  map.on('moveend', reportQuad);
  reportQuad();
})();
</script>
</body>
</html>