139 lines
3.9 KiB
JavaScript

L.BingLayer = L.TileLayer.extend({
options: {
subdomains: [0, 1, 2, 3],
type: 'Aerial',
attribution: 'Bing',
culture: ''
},
initialize: function(key, options) {
L.Util.setOptions(this, options);
this._key = key;
this._url = null;
this.meta = {};
this.loadMetadata();
},
tile2quad: function(x, y, z) {
var quad = '';
for (var i = z; i > 0; i--) {
var digit = 0;
var mask = 1 << (i - 1);
if ((x & mask) != 0) digit += 1;
if ((y & mask) != 0) digit += 2;
quad = quad + digit;
}
return quad;
},
getTileUrl: function(p, z) {
var z = this._getZoomForUrl();
var subdomains = this.options.subdomains,
s = this.options.subdomains[Math.abs((p.x + p.y) % subdomains.length)];
return this._url.replace('{subdomain}', s)
.replace('{quadkey}', this.tile2quad(p.x, p.y, z))
.replace('http:', document.location.protocol)
.replace('{culture}', this.options.culture);
},
loadMetadata: function() {
//MODIFIED: use browser sessionStorage, if available, to cache the metadata
var _this = this;
var cbid = '_bing_metadata_' + L.Util.stamp(this);
var cachedMetadataKey = '_Leaflet_Bing_metadata_'+this.options.type;
try {
if (sessionStorage[cachedMetadataKey]) {
this.meta = JSON.parse(sessionStorage[cachedMetadataKey]);
this.initMetadata();
return;
}
} catch(e) {}
window[cbid] = function (meta) {
_this.meta = meta;
window[cbid] = undefined;
var e = document.getElementById(cbid);
e.parentNode.removeChild(e);
if (meta.errorDetails) {
if (window.console) console.log("Leaflet Bing Plugin Error - Got metadata: " + meta.errorDetails);
return;
}
try {
sessionStorage[cachedMetadataKey] = JSON.stringify(meta);
} catch(e) {}
_this.initMetadata();
};
var url = document.location.protocol + "//dev.virtualearth.net/REST/v1/Imagery/Metadata/" + this.options.type + "?include=ImageryProviders&jsonp=" + cbid + "&key=" + this._key;
var script = document.createElement("script");
script.type = "text/javascript";
script.src = url;
script.id = cbid;
document.getElementsByTagName("head")[0].appendChild(script);
},
initMetadata: function() {
var r = this.meta.resourceSets[0].resources[0];
this.options.subdomains = r.imageUrlSubdomains;
this._url = r.imageUrl;
this._providers = [];
if (r.imageryProviders) {
for (var i = 0; i < r.imageryProviders.length; i++) {
var p = r.imageryProviders[i];
for (var j = 0; j < p.coverageAreas.length; j++) {
var c = p.coverageAreas[j];
var coverage = {zoomMin: c.zoomMin, zoomMax: c.zoomMax, active: false};
var bounds = new L.LatLngBounds(
new L.LatLng(c.bbox[0]+0.01, c.bbox[1]+0.01),
new L.LatLng(c.bbox[2]-0.01, c.bbox[3]-0.01)
);
coverage.bounds = bounds;
coverage.attrib = p.attribution;
this._providers.push(coverage);
}
}
}
this._update();
},
_update: function() {
if (this._url == null || !this._map) return;
this._update_attribution();
L.TileLayer.prototype._update.apply(this, []);
},
_update_attribution: function() {
var bounds = this._map.getBounds();
var zoom = this._map.getZoom();
for (var i = 0; i < this._providers.length; i++) {
var p = this._providers[i];
if ((zoom <= p.zoomMax && zoom >= p.zoomMin) &&
bounds.intersects(p.bounds)) {
if (!p.active && this._map.attributionControl)
this._map.attributionControl.addAttribution(p.attrib);
p.active = true;
} else {
if (p.active && this._map.attributionControl)
this._map.attributionControl.removeAttribution(p.attrib);
p.active = false;
}
}
},
onRemove: function(map) {
for (var i = 0; i < this._providers.length; i++) {
var p = this._providers[i];
if (p.active && this._map.attributionControl) {
this._map.attributionControl.removeAttribution(p.attrib);
p.active = false;
}
}
L.TileLayer.prototype.onRemove.apply(this, [map]);
}
});
L.bingLayer = function (key, options) {
return new L.BingLayer(key, options);
};