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openlayersopenlayers-5

Openlayers - shifted map


I get data like in example in this post How to fix EPSG:4326 with WMTS incorrect map overlay ,which even has the same source I just need. However, the map is shifted.

private createLayer() {
this.service
  .getTypesLayersFilter()
  .subscribe((resp: TypesLayersFilters) => {
    const filter = first(resp.WMTS);
    const parser = new WMTSCapabilities();
    const layer = 'ORTOFOTOMAPA';
    const matrixSet = 'EPSG:4326';

    this.wmtsService.getData().subscribe(text => {
      const result = parser.read(text);
      const options = optionsFromCapabilities(result, {
        layer,
        matrixSet,
        crossOrigin: true
      });

      const layerNew = new TileLayer({
        source: new WMTS(options),
        opacity: 0.7,
        name: 'WMTS',
      });

    });
  });
}

Source: https://mapy.geoportal.gov.pl/wss/service/WMTS/guest/wmts/ORTO?SERVICE=WMTS&REQUEST=GetCapabilities

getData() {
const url =
  'https://mapy.geoportal.gov.pl/wss/service/WMTS/guest/wmts/ORTO';
const data = {
  SERVICE: 'WMTS',
  REQUEST: 'GetCapabilities'
};
const options: any = { params: data, responseType: 'text' };

return this.http.get(url, {
  ...options,
  params: this.toHttpParams(options.params)
});
}

map screenshot

What can cause this shift, am I doing something wrong? Maybe the solution would be to move the map, if possible and that's how it should be done ?


Solution

  • I have added some opacity to the example and can see that the tilegrid defined by the GetCapabilities isn't exactly positioned in EPSG:4326. The service also supports EPSG:2180 which seems to fit much better. Using that projection will need proj4 and you will need to include +axis=neu in the projection definition as the service use a northing-easting coordinate order.

    proj4.defs('EPSG:2180', '+proj=tmerc +lat_0=0 +lon_0=19 +k=0.9993 +x_0=500000 +y_0=-5300000 +ellps=GRS80 +units=m +axis=neu +no_defs ');
    
    ol.proj.proj4.register(proj4);
    
    var parser = new ol.format.WMTSCapabilities();
    var url = 'https://mapy.geoportal.gov.pl/wss/service/WMTS/guest/wmts/ORTO?SERVICE=WMTS&REQUEST=GetCapabilities';
    
    fetch(url).then(function(response) {
      return response.text();
    }).then(function(text) {
      var result = parser.read(text);
      var options = ol.source.WMTS.optionsFromCapabilities(result, {
        layer: 'ORTOFOTOMAPA',
        matrixSet: 'EPSG:2180',
        crossOrigin: true,
      });
      //console.log(options);
    
      this.map = new ol.Map({
        layers: [
          new ol.layer.Tile({
            source: new ol.source.OSM()
          }),
          new ol.layer.Tile({
            source: new ol.source.WMTS(options),
            opacity: 0.5
          })
        ],
        target: "map",
        view: new ol.View({
          center: ol.proj.fromLonLat([19.4569911, 51.7687323]),
          zoom: 4
        })
      });
    
    });
    html, body, .map {
        margin: 0;
        padding: 0;
        width: 100%;
        height: 100%;
    }
    <link href="https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.3.0/css/ol.css" rel="stylesheet" />
    <script src="https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.3.0/build/ol.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/proj4js/2.5.0/proj4.js"></script>
    <div id="map" class="map"></div>