Center

<!--
  说明：把要素固定在指定像素位置的中文示例，数据在页面内生成，可独立运行。
  核心逻辑：getCoordinateFromPixel + 分辨率换算，让几何落在固定像素
  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>把要素固定在指定像素位置</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}
  .bar{flex:0 0 auto;padding:8px 12px;background:#f6f7f9;border-bottom:1px solid #e3e6ea;
       display:flex;gap:10px;align-items:center;flex-wrap:wrap;font-size:12px;color:#58606e}
  .bar label{display:flex;gap:5px;align-items:center;cursor:pointer}
  .bar button{font:inherit;padding:3px 9px;border:1px solid #c9ced6;background:#fff;
       border-radius:5px;cursor:pointer;color:#333}
  .bar button:hover{background:#eef2f8}
  .bar input[type=range]{width:110px;vertical-align:middle}
  .bar input[type=text]{font:inherit;padding:2px 6px;border:1px solid #c9ced6;border-radius:4px}
  #map{flex:1 1 auto;min-height:0;background:#eef0f3;position:relative}
  .panel{flex:0 0 auto;max-height:34%;overflow:auto;padding:8px 12px;font-size:12px;
       background:#fff;border-top:1px solid #e3e6ea;color:#3d4451}
  .panel pre{margin:0;font-family:Consolas,"Courier New",monospace;font-size:11px;
       white-space:pre-wrap;word-break:break-all;line-height:1.5}
  .ol-attribution{font-size:11px}

</style>
</head>
<body>
<div class="bar">
<label>对准 <select id="target">
  <option value="0">天安门</option>
  <option value="1">外滩</option>
  <option value="2">乌鲁木齐</option>
</select></label>
<button id="again" type="button">对准</button>
<span id="info">—</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 (typeof ol === 'undefined') {
    var errBox = document.getElementById('map');
    if (errBox) {
      errBox.innerHTML = '<div style="padding:20px;color:#b42318">OpenLayers 加载失败，请检查能否访问 cdn.jsdelivr.net</div>';
    }
    return;
  }

  var fromLonLat = ol.proj.fromLonLat;
  var targets = [
    [116.391263, 39.907359, '天安门'],
    [121.490300, 31.239700, '外滩'],
    [87.616800, 43.825600, '乌鲁木齐']
  ];
  var pixel = [140, 110];

  var view = new ol.View({center: fromLonLat([116.391263, 39.907359]), zoom: 12});
  var source = new ol.source.Vector();
  targets.forEach(function (t, i) {
    source.addFeature(new ol.Feature({
      geometry: new ol.geom.Point(fromLonLat([t[0], t[1]])),
      name: t[2],
      idx: i
    }));
  });

  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.Vector({
        source: source,
        style: new ol.style.Style({
          image: new ol.style.Circle({
            radius: 5,
            fill: new ol.style.Fill({color: '#d13b2f'}),
            stroke: new ol.style.Stroke({color: '#ffffff', width: 2})
          }),
          text: new ol.style.Text({
            text: '',
            offsetY: -16,
            font: '500 12px sans-serif',
            fill: new ol.style.Fill({color: '#16181d'}),
            stroke: new ol.style.Stroke({color: '#ffffff', width: 3})
          })
        })
      })
    ],
    view: view,
    controls: ol.control.defaults.defaults({attribution: false, zoom: true, rotate: false})
  });

  /* 十字圈固定在地图的 (140, 110) 像素处 */
  var cross = document.createElement('div');
  cross.style.cssText = 'position:absolute;left:' + pixel[0] + 'px;top:' + pixel[1] + 'px;' +
    'width:22px;height:22px;margin:-11px 0 0 -11px;border:2px solid #1f5fd0;border-radius:50%;' +
    'background:rgba(31,95,208,0.08);box-shadow:0 0 0 2px rgba(255,255,255,0.85);pointer-events:none';
  document.getElementById('map').appendChild(cross);

  var info = document.getElementById('info');
  var sel = document.getElementById('target');

  function align() {
    var t = targets[+sel.value];
    var coord = fromLonLat([t[0], t[1]]);
    var size = map.getSize();
    if (!size) { return; }
    var res = view.getResolution();
    view.setCenter([
      coord[0] - (pixel[0] - size[0] / 2) * res,
      coord[1] + (pixel[1] - size[1] / 2) * res
    ]);
    info.textContent = t[2] + ' 钉在 (' + pixel[0] + ', ' + pixel[1] + ') px · 经纬度 ' +
      t[0].toFixed(3) + ', ' + t[1].toFixed(3);
  }

  map.once('postrender', align);
  sel.addEventListener('change', align);
  document.getElementById('again').addEventListener('click', align);
  map.on('moveend', function () {
    if (!map.getSize()) { return; }
    var t = targets[+sel.value];
    var px = map.getPixelFromCoordinate(fromLonLat([t[0], t[1]]));
    info.textContent = '目标当前位于 (' + px[0].toFixed(0) + ', ' + px[1].toFixed(0) + ') px，点击「对准」复位';
  });
})();
</script>
</body>
</html>