Proj4Leaflet orign on custom projection



我使用神话般的Proj4Leaflet插件设置了一个传单地图。在我的地图中,我使用的是自定义参考系(EPSG:28533)。将获取和呈现地图切片(WMTSCapability)。但是我遇到过瓷砖被转换到错误的位置。偏移量约为+9°纬度+7°液化天然气。我希望,我在参考系统(小提琴)的定义中设置了错误的origin

var rs25832 = new L.Proj.CRS(
    'EPSG:25832',
    '+proj=utm +zone=32 +ellps=GRS80 +units=m +no_defs', {
        origin: [
            // I suppose the error is here!
            265948.8191,
            7288831.7014
        ],
        resolutions: [
            // TileMatrixScaleDenominator * OGC_PixelWidth
            17471320.7509   * 0.00028,
            8735660.37545   * 0.00028,
            4367830.18772   * 0.00028,
            2183915.09386   * 0.00028,
            1091957.54693   * 0.00028,
            545978.773466   * 0.00028,
            272989.386733   * 0.00028,
            136494.693366   * 0.00028,
            68247.3466832   * 0.00028,
            34123.6733416   * 0.00028,
            17061.8366708   * 0.00028,
            8530.9183354    * 0.00028,
            4265.4591677    * 0.00028,
            2132.72958385   * 0.00028
        ]
    }
);
var url = 'http://sg.geodatenzentrum.de/wmts_webatlasde/tile/1.0.0/webatlasde/default/DE_EPSG_25832_ADV/{z}/{y}/{x}.png';      
var layer = L.tileLayer(url, {
        maxZoom: rs25832.options.resolutions.length,
        continuousWorld: true
    }
);
var map = L.map('map', {
    crs: rs25832,
    center: [ 50.5881112, 7.2676084 ],
    zoom: 0,
    maxZoom: rs25832.options.resolutions.length,
    layers: [ layer ]
});
map.on('click', function(e) {
    alert('lat: ' + e.latlng.lat + ' lng: ' + e.latlng.lng)
});

据我所知,origin设置定义了引用系统投影边界的左上角。根据 spatialreference.org 定义,这个特定参考系统的边界是:

265948.8191, 6421521.2254, 677786.3629, 7288831.7014

我是否使用了错误的方法来确定CRS origin

我已经解决了这个问题!问题正如预期的那样,origin属性的磨皮方法。我以为参考系的origin应该等于参考系投影边界的左上角。但我错了。正确的方法是使用图层BBox的左上角。基于服务器的WMTSCapability,我能够使用proj4js计算预计origin。这是我更新的代码(小提琴):

// Proj4js EPSG:25832 definition
var proj4rs25832def = '+proj=utm +zone=32 +ellps=GRS80 +units=m +no_defs';
// Calc origin
var orign = proj4(
    proj4rs25832def,
    // Upper left corner of the tile orign based on the WMTSCapabilities layer BBox
    [ 0.105946948013, 56.8478734515 ]
);
// Set resolutions
var resolutions = [ 17471320.7509, 8735660.37545, 4367830.18772, 2183915.09386, 1091957.54693, 545978.773466, 272989.386733, 136494.693366, 68247.3466832, 34123.6733416, 17061.8366708, 8530.9183354, 4265.4591677, 2132.72958385 ];
// Define CRS
var rs25832 = new L.Proj.CRS(
    'EPSG:25832',
    proj4rs25832def, 
    {
        origin: [ orign[0], orign[1] ],
        resolutions: resolutions.map(function (value) {
            return value * 0.00028;
        })
    }
);
// Create layer
var url = 'http://sg.geodatenzentrum.de/wmts_webatlasde/tile/1.0.0/webatlasde/default/DE_EPSG_25832_ADV/{z}/{y}/{x}.png';      
var layer = L.tileLayer(
    url, 
    {
        continuousWorld: true,
        bounds: [[ 45.2375, 0.1059 ],[ 56.8478, 20.4488 ]],
        maxZoom: resolutions.length
    }
);
// Setup map
var map = L.map('map', {
    crs: rs25832,
    center: [ 50.8805, 7.3389 ],
    zoom: 0,
    maxZoom: resolutions.length,
    layers: [ layer ]
});
// Setup click hander
map.on('click', function(e) {
  alert('lat: ' + e.latlng.lat + ' lng: ' + e.latlng.lng);
  console.log(e.latlng);
});

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