Map repeats three times at zoom 3 because noWrap is off

• Three copies of China appear at zoom 3 and five at zoom 2
• World width at z3 is 8 x 256 = 2048 px against a 1600 px container, so wrapping kicks in
• Repeated copies show the same tile or 404s because the service covers only China

1. Compute `2^z * tileSize` and compare it with the container width
2. Check the `noWrap` option, which defaults to `false`
3. Check whether `bounds` or `maxBounds` is set
4. Check whether `minZoom` is below the service's real minimum of 3 or 4
5. Reproduce at zoom 2 and 3 and count the repeats

Set `noWrap: true` with `minZoom: 4` and `bounds: [[3.5, 73.0], [53.6, 135.1]]`, and constrain the map with `maxBounds` plus `maxBoundsViscosity: 0.8`; in OpenLayers set `wrapX: false` on the XYZ source.

const worldWidth = Math.pow(2, map.getZoom()) * 256;
console.log(worldWidth, map.getSize().x);
// 2 级: 1024 vs 1600  -> 世界比视口窄，必然重复

L.tileLayer('https://tile.example.com/{z}/{x}/{y}.png', {
  minZoom: 4,
  maxZoom: 18,
  noWrap: true,
  bounds: [[3.5, 73.0], [53.6, 135.1]]   // 中国范围
}).addTo(map);
const map = L.map('map', {
  minZoom: 4,
  maxBounds: [[3.5, 73.0], [53.6, 135.1]],
  maxBoundsViscosity: 0.8
});

• Setting only `noWrap` without raising `minZoom`, so zoom 2 still shows a world narrower than the viewport with broken edges
• Using `maxBounds` alone with a low `minZoom`, which still lets the viewport pull repeated tiles into view