forked from expo/troggle
35 lines
822 B
JavaScript
35 lines
822 B
JavaScript
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function BGSTileURL ( x, y, z ) {
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var earthRadius = 6378137; // in meters
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var tileCount = Math.pow( 2, z );
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var tileSize = earthRadius * 2 * Math.PI / tileCount;
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var x1, x2, y1, y2;
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x = x - tileCount / 2;
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y = tileCount / 2 - y;
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x1 = x * tileSize;
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y1 = y * tileSize;
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x2 = x1 + tileSize;
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y2 = y1 + tileSize;
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var url = 'https://map.bgs.ac.uk/arcgis/services/BGS_Detailed_Geology/MapServer/WMSServer?REQUEST=GetMap&VERSION=1.3.0&LAYERS=BGS.50k.Bedrock&STYLES=default&FORMAT=image/png&CRS=EPSG:3857&WIDTH=450&HEIGHT=450';
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var bbox = '&BBOX=' + x1 + ',' + y1 + ',' + x2 + ',' + y2;
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console.log( 'BGS: ', bbox );
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// var img = document.createElement( 'img' );
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// img.src = url + bbox;
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// img.crossOrigin = '';
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// document.body.appendChild( img );
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return url + bbox;
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}
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