4

I have an OpenLayers map with EPSG:3857 projection. I would like to add WMTS layer http://mapy.geoportal.gov.pl/wss/service/WMTS/guest/wmts/ORTO which support only matrix for EPSG:2180 and 4326.

Is any way to reproject this WMTS layer?

I was trying with this code but the layer is shown in wrong place.

    var WMTS2 = new ol.layer.Tile({
                    opacity: 0.5,
                    extent: projectionExtent,
                    source: new ol.source.WMTS({
                        url: 'http://mapy.geoportal.gov.pl/wss/service/WMTS/guest/wmts/ORTO',
                        layer: 'ORTOFOTOMAPA',
                        matrixSet: '2180',
                        format: 'image/jpeg',
                        projection: 'EPSG:2180',
                        tileGrid: new ol.tilegrid.WMTS({
                            origin: ol.extent.getTopLeft(projectionExtent),
                            resolutions: resolutions,
                            matrixIds: matrixIds
                        }),
                        extent: projectionExtent,
                        style: 'default'
                    })
                });     
  • You might have a go looking here Openlayers site – cm1 Aug 22 '18 at 15:48
  • I used this metod above, but I don't know how Matrix reproject. The layers is placed in a wrong place on map. – Lukasz Aug 23 '18 at 9:51
2

I tried setting that up using ol.source.WMTS.optionsFromCapabilities but it didn't work because the GetCapabilities lists the TopLeftCorner as 850000.0 100000.0 which is somewhere in Ukraine. However I suspected the x and y were reversed and used the matrixIds, resolutions and tileSize returned by optionsFromCapabilities but changed the origin: [850000, 100000] to [100000, 850000] and it worked:

              tileGrid: new ol.tilegrid.WMTS({
                  origin: [100000, 850000],
                  matrixIds: ["EPSG:2180:0",
                              "EPSG:2180:1",
                              "EPSG:2180:2",
                              "EPSG:2180:3",
                              "EPSG:2180:4",
                              "EPSG:2180:5",
                              "EPSG:2180:6",
                              "EPSG:2180:7",
                              "EPSG:2180:8",
                              "EPSG:2180:9",
                              "EPSG:2180:10",
                              "EPSG:2180:11",
                              "EPSG:2180:12",
                              "EPSG:2180:13"],
                 resolutions: [2116.6709,
                               1058.33545,
                                529.167725,
                                264.5838625,
                                132.29193125,
                                 66.145965625,
                                 26.458386249999997,
                                 13.229193124999998,
                                  6.614596562499999,
                                  2.645838625,
                                  1.3229193125,
                                  0.529167725,
                                  0.2645838625,
                                  0.13229193125],
                 tileSize: 512
              })

enter image description here

  • The service works fine for me in QGIS using either EPSG:2180 or EPSG:4326, so it doesn't look like coordinates are flipped. For EPSG:2180 x axis is Northing (epsg-registry.org/export.htm?wkt=urn:ogc:def:crs:EPSG::2180) and for EPSG:4326 x axis is latitiude (epsg-registry.org/export.htm?wkt=urn:ogc:def:crs:EPSG::4326) – nmtoken Dec 6 '18 at 9:28
  • Those definitions won't work with OpenLayers. In OpenLayers EPSG:4326 is predefined as LonLat, all other projections except EPSG:3857 require proj4 and are x, y unless the proj4 definition specifies "+axis=neu", which it doesn't epsg.io/2180. Depending on your opinion either OpenLayers, the proj4 definition, or the WMTS service are incompatible. There are similar issues with EPSG:31254. – Mike Dec 6 '18 at 10:40
  • OpenLayers has it wrong then. OpenLayers can't define the axes order for EPSG projections, only EPSG can do that. – nmtoken Dec 6 '18 at 12:10
  • epsg.io is not the official registry of EPSG codes, you can't use it as the definitive source of axes order, you have to go to epsg-registry.org – nmtoken Dec 6 '18 at 12:14
  • 1
    Now I have seen the correct WKT for 2180 it's clear the WMTS service isn't incorrect, but it inconsistent with OpenLayers. Somewhere in the code will be a proj4 definition string which defaults to enu so OL does honour the correct axes order which it has been given, so neither is OpenLayers incorrect there. Either the proj4 definition needs to be updated, or the matrix origin needs to be specified in the x, y format. In this case option 2 was easier.. – Mike Dec 6 '18 at 14:04

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