您好，wmts-china的矩阵集与默认的mapboxgl的层级不对应，推荐使用wmts100接口对接map-china400服务，修改原wmts-china接口方式比较繁琐且需要修改iServer配置文件，不推荐。
以下为通过wmts100接口添加服务至mapboxgl的示例代码。
希望能帮到您。
<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8' />
<meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
<title data-i18n="resources.title_tiledMapLayer"></title>
<script type="text/javascript" src="../js/include-web.js"></script>
<style>
body {
margin: 0;
padding: 0;
}
#map {
position: absolute;
top: 0;
bottom: 0;
width: 100%;
}
</style>
</head>
<body>
<div id='map'></div>
<script type="text/javascript" include="mapbox-gl-enhance" src="../../dist/mapboxgl/include-mapboxgl.js"></script>
<script type="text/javascript">
var host = window.isLocal ? window.server : "https://iserver.supermap.io";
var attribution = "<a href='https://www.mapbox.com/about/maps/' target='_blank'>© Mapbox </a>" +
" with <span>© <a href='https://iclient.supermap.io' target='_blank'>SuperMap iClient</a> | </span>" +
" Map Data <span>© <a href='http://support.supermap.com.cn/product/iServer.aspx' target='_blank'>SuperMap iServer</a></span> ";
var map = new mapboxgl.Map({
container: 'map', // container id
style: {
"version": 8,
"sources": {
"raster-tiles": {
"attribution": attribution,
"type": "raster",
"tiles": ['https://iserver.supermap.io/iserver/services/map-china400/wmts100?layer=China_4490&style=default&tilematrixset=Custom_China_4490&Service=WMTS&Request=GetTile&Version=1.0.0&Format=image/png&TileMatrix={z}&TileCol={x}&TileRow={y}'],
"tileSize": 256
}
},
"layers": [{
"id": "simple-tiles",
"type": "raster",
"source": "raster-tiles",
"minzoom": 0,
"maxzoom": 22
}]
},
center: [0, 0], // starting position
zoom: 0, // starting zoom
crs: 'EPSG:4490',
});
map.addControl(new mapboxgl.NavigationControl(), 'top-left');
</script>
</body>
</html>
