mapbox加载postgis矢量切片

基于postgis函数计算矢量切片并通过mapbox和arcgis js 3.x加载：https://www.pianshen.com/article/90461612366/

https://github.com/xiaopaoge/postgis-stMvt

原理：

1. 首先在前端依赖js类库算法将当前的地图范围（extent）和缩放级别（extent）自动计算出列号（x）、行号（y）、级别（z）。会计算出多个瓦片坐标（z，x,y）。

2.将这些瓦片坐标当做实参（{z}、{x}、{y}）依次循环传入到后台的服务（后台对应着三个形参）

3.将瓦片坐标转换为经纬度，因为只有这样才能依靠经纬度（4326）或平面坐标（3857）范围查询对应数据库的数据。

4.将查询出的数据转换为mvt格式（实际是一个二进制流格式数据）。

SELECT ST_AsMVT(tile,'lines',4096,'geom') tile
FROM(SELECT fs_name,ST_AsMVTGeom(geom,ST_Transform(ST_MakeEnvelope(%s,%s,%s,%s, 4326),3857),4096, 256, true) AS geom
FROM  public.pipesectionmpa_4326_3857 ) AS  tile;

5. 依次返回给前端，前端将数据绘制到地图上。另外，可以根据match对某个字段值进行分值设色。

参考：https://blog.csdn.net/xlp789/article/details/103503348

但是并不能。。

源码1：

<!DOCTYPE html>
<html>
<head>
   <meta charset='utf-8' />
   <title>Display a map</title>
   <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
   <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.41.0/mapbox-gl.js'></script>;
   <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.41.0/mapbox-gl.css' rel='stylesheet' />
   <style>
       body { margin:0; padding:0; }
       #map { position:absolute; top:0; bottom:0; width:100%; }
   </style>
</head>
<body>
<div id='map'></div>
<script>
   //使用注册Mapbox时候后台自动生成的token
   mapboxgl.accessToken = ‘yourToken’;
   var map = new mapboxgl.Map({
       container: 'map', // 放置的div的id
       style: 'mapbox://styles/mapbox/streets-v9',
       center: [116.466, 40.035],// 地图显示中心点位置
       zoom: 8,// 开始的缩放级别
       maxZoom: 16
   });
   map.on('load', function() {
       //访问本地的服务器
       var bjroad_tile_source = {
           type: 'vector',
           tiles: [
               'http://localhost:8000/tiles-bjroad3857-vector/{z}/{x}/{y}.pbf'
           ],
           maxzoom: 14
       };
       var usa_tile_source = {
           type: 'vector',
           tiles: [
               'http://localhost:8000/tile-usa4326-vector/{z}/{x}/{y}.pbf'
           ],
           maxzoom: 14
       };
//注意:这里的'source-layer'要与mbtiles数据集中所使用的图层名称(id)保持一致!
       var bjroad_polygon_layer = {
           'id': 'bjroad_polygon_id',
           'type': 'fill',
           'source': 'bjroad_tile_source',
           'source-layer': 'BJ_LN_3857',  
           'paint': {
               "fill-color": "#00ffff",
               "fill-opacity": 1,
               "fill-outline-color": "#ff0000"
           }
       };
       var bjroad_normal_line_layer = {
           'id': 'bjroad_normal_line_id',
           'type': 'line',
           'source': 'bjroad_tile_source',
           'source-layer': 'BJ_LN_3857',
           'layout': {
               'line-join': 'round',
               'line-cap': 'round'
           },
           'paint': {
               "line-color": "#0000ff",
               "line-width": 1
           }
       };
       var usa_polygon_layer = {
           'id': 'usa_polygon_id',
           'type': 'fill',
           'source': 'usa_tile_source',
           'source-layer': 'usa4326',  
           'paint': {
               "fill-color": "#00ffff",
               "fill-opacity": 1,
               "fill-outline-color": "#ff0000"
           }
       };
       var usa_normal_line_layer = {
           'id': 'usa_normal_line_id',
           'type': 'line',
           'source': 'usa_tile_source',
           'source-layer': 'usa4326',
           'layout': {
               'line-join': 'round',
               'line-cap': 'round'
           },
           'paint': {
               "line-color": "#0000ff",
               "line-width": 1
           }
       };
      
       map.addSource('bjroad_tile_source', bjroad_tile_source);
       map.addSource('usa_tile_source', usa_tile_source);
       //map.addLayer(bjroad_polygon_layer);
       map.addLayer(bjroad_normal_line_layer);
       map.addLayer(usa_normal_line_layer);
   });
</script>
</body>
</html>

https://blog.csdn.net/luochanxiong6435/article/details/79744415

<!DOCTYPE html>
<html>
 
<head>
    <meta charset='utf-8' />
    <title>Add a third party vector tile source</title>
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='mapbox-gl.js'></script>
    <link href='mapbox-gl.css' rel='stylesheet' />
    <style>
        body {
            margin: 0;
            padding: 0;
        }
        
        #map {
            position: absolute;
            top: 0;
            bottom: 0;
            width: 100%;
        }
    </style>
</head>
 
<body>
 
    <div id='map'></div>
    <script>
        mapboxgl.accessToken = undenfined;
        var tileset = 'mapbox.streets';
        var map = new mapboxgl.Map({
            container: 'map',
            zoom: 12,
            center: [109.898625809072612, 19.106708155556731],
            style: 'mapbox://styles/mapbox/light-v9',
            hash: false
        });
 
        map.on('load', function loaded() {
            map.addSource('custom-go-vector-tile-source', {
                type: 'vector',
                tiles: ['http://localhost:8081/tiles/{z}/{x}/{y}']
            });
            map.addLayer({
                id: 'background',
                type: 'background',
                paint: {
                    'background-color': 'white'
                }
            });
            map.addLayer({
                "id": "custom-go-vector-tile-layer",
                "type": "circle",
                "source": "custom-go-vector-tile-source",
                "source-layer": "points",
                paint: {
                    'circle-radius': {
                        stops: [
                            [8, 0.1],
                            [11, 0.5],
                            [15, 3],
                            [20, 20]
                        ]
                    },
                    'circle-color': '#e74c3c',
                    'circle-opacity': 1
                }
            });
        });
    </script>
 
</body>
 
</html>

参考：Node+JavaScript：https://blog.csdn.net/aicuo0508/article/details/102330219 Go+JavaScript：https://github.com/vicapow/go-vtile-example

（小贴士:sql中‘points’的字符串与渲染中mapbox里的source-layer一致）

SELECT ST_AsMVT(tile,'points') tile  FROM(
SELECT ST_AsMVTGeom(geom,ST_MakeEnvelope(100,10,125,22, 4326),4096, 0, true)    
 AS geom FROM grid20180322 ) 
AS  tile where  tile.geom is not null

>>基于PostGIS动态矢量切片实践：https://zhuanlan.zhihu.com/p/349849542 https://blog.crunchydata.com/blog/dynamic-vector-tiles-from-postgis

posted on 2021-07-28 11:55 XiaoNiuFeiTian 阅读(1285) 评论(0) 编辑收藏举报

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