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Leaflet mouse position plugin adapted for BNG (EPSG:27700)
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| //Adpated by mtravis from https://github.com/ardhi/Leaflet.MousePosition/ for use with BNG co-ords. Inspired by http://ghost.mixedbredie.net/reprojecting-leaflet-coordinates/ | |
| //You will still need Leaflet.MousePosition/src/L.Control.MousePosition.css from the original repo for this to work | |
| //Also include a link to https://cdnjs.cloudflare.com/ajax/libs/proj4js/2.3.10/proj4.js | |
| //Finally add L.control.mousePosition().addTo(map); to the your script | |
| L.Control.MousePosition = L.Control.extend({ | |
| options: { | |
| position: 'bottomleft', | |
| separator: ' : ', | |
| emptyString: 'Unavailable', | |
| lngFirst: true, | |
| numDigits: 5, | |
| lngFormatter: undefined, | |
| latFormatter: undefined, | |
| prefix: "" | |
| }, | |
| onAdd: function (map) { | |
| this._container = L.DomUtil.create('div', 'leaflet-control-mouseposition'); | |
| L.DomEvent.disableClickPropagation(this._container); | |
| map.on('mousemove', this._onMouseMove, this); | |
| this._container.innerHTML=this.options.emptyString; | |
| return this._container; | |
| }, | |
| onRemove: function (map) { | |
| map.off('mousemove', this._onMouseMove) | |
| }, | |
| _onMouseMove: function (e) { | |
| var bngproj = '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs'; | |
| var bngcoords = proj4(bngproj, [e.latlng.lng, e.latlng.lat]); | |
| east = bngcoords[0].toFixed(0) | |
| north = bngcoords[1].toFixed(0) | |
| var lng = L.Util.formatNum(east, 6) + ' E'; | |
| var lat = L.Util.formatNum(north, 5) + ' N'; | |
| var value = this.options.lngFirst ? lng + this.options.separator + lat : lat + this.options.separator + lng; | |
| var prefixAndValue = this.options.prefix + ' ' + value; | |
| this._container.innerHTML = prefixAndValue; | |
| } | |
| }); | |
| L.Map.mergeOptions({ | |
| positionControl: false | |
| }); | |
| L.Map.addInitHook(function () { | |
| if (this.options.positionControl) { | |
| this.positionControl = new L.Control.MousePosition(); | |
| this.addControl(this.positionControl); | |
| } | |
| }); | |
| L.control.mousePosition = function (options) { | |
| return new L.Control.MousePosition(options); | |
| }; |
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