512-pixel tiles laid out as 256: blurry basemap and shifted features

• A tile's `naturalWidth` is 512 while its DOM `clientWidth` is 256
• Roads and vector points are offset by about 200 px, growing away from the center
• The same zoom level looks blurrier than the previous 256-pixel service

1. Check the intrinsic size of a tile in the network panel
2. Read the width style on `.leaflet-tile` in the DOM
3. Measure the offset at a tile boundary; half a tile width indicates the mismatch
4. Check whether `detectRetina` is also enabled
5. Confirm the service's real tile size from its documentation

Set `tileSize: 512` together with `zoomOffset: -1` and `detectRetina: false`; in OpenLayers pass `tileSize: 512` to the source and `createXYZ({ tileSize: 512, maxZoom: 19 })` to the tile grid.

const img = document.querySelector('.leaflet-tile');
console.log(img.naturalWidth, img.clientWidth);   // 512 256  <- 尺寸不匹配

L.tileLayer('https://tile.example.com/{z}/{x}/{y}.png', {
  tileSize: 512,
  zoomOffset: -1,
  minZoom: 1,
  maxZoom: 19,
  detectRetina: false        // 已经用 512 了，不要再开
}).addTo(map);

• Keeping `tileSize: 256` for 512-pixel tiles, which downscales the image and halves its coverage
• Combining `detectRetina: true` with 512 tiles and `zoomOffset: -1`, where the two compensations cancel and levels skip