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Diffstat (limited to 'misc/openlayers/lib/OpenLayers/Layer/XYZ.js')
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Layer/XYZ.js | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/misc/openlayers/lib/OpenLayers/Layer/XYZ.js b/misc/openlayers/lib/OpenLayers/Layer/XYZ.js new file mode 100644 index 0000000..5af5ce3 --- /dev/null +++ b/misc/openlayers/lib/OpenLayers/Layer/XYZ.js @@ -0,0 +1,172 @@ +/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for + * full list of contributors). Published under the 2-clause BSD license. + * See license.txt in the OpenLayers distribution or repository for the + * full text of the license. */ + +/** + * @requires OpenLayers/Layer/Grid.js + */ + +/** + * Class: OpenLayers.Layer.XYZ + * The XYZ class is designed to make it easier for people who have tiles + * arranged by a standard XYZ grid. + * + * Inherits from: + * - <OpenLayers.Layer.Grid> + */ +OpenLayers.Layer.XYZ = OpenLayers.Class(OpenLayers.Layer.Grid, { + + /** + * APIProperty: isBaseLayer + * Default is true, as this is designed to be a base tile source. + */ + isBaseLayer: true, + + /** + * APIProperty: sphericalMercator + * Whether the tile extents should be set to the defaults for + * spherical mercator. Useful for things like OpenStreetMap. + * Default is false, except for the OSM subclass. + */ + sphericalMercator: false, + + /** + * APIProperty: zoomOffset + * {Number} If your cache has more zoom levels than you want to provide + * access to with this layer, supply a zoomOffset. This zoom offset + * is added to the current map zoom level to determine the level + * for a requested tile. For example, if you supply a zoomOffset + * of 3, when the map is at the zoom 0, tiles will be requested from + * level 3 of your cache. Default is 0 (assumes cache level and map + * zoom are equivalent). Using <zoomOffset> is an alternative to + * setting <serverResolutions> if you only want to expose a subset + * of the server resolutions. + */ + zoomOffset: 0, + + /** + * APIProperty: serverResolutions + * {Array} A list of all resolutions available on the server. Only set this + * property if the map resolutions differ from the server. This + * property serves two purposes. (a) <serverResolutions> can include + * resolutions that the server supports and that you don't want to + * provide with this layer; you can also look at <zoomOffset>, which is + * an alternative to <serverResolutions> for that specific purpose. + * (b) The map can work with resolutions that aren't supported by + * the server, i.e. that aren't in <serverResolutions>. When the + * map is displayed in such a resolution data for the closest + * server-supported resolution is loaded and the layer div is + * stretched as necessary. + */ + serverResolutions: null, + + /** + * Constructor: OpenLayers.Layer.XYZ + * + * Parameters: + * name - {String} + * url - {String} + * options - {Object} Hashtable of extra options to tag onto the layer + */ + initialize: function(name, url, options) { + if (options && options.sphericalMercator || this.sphericalMercator) { + options = OpenLayers.Util.extend({ + projection: "EPSG:900913", + numZoomLevels: 19 + }, options); + } + OpenLayers.Layer.Grid.prototype.initialize.apply(this, [ + name || this.name, url || this.url, {}, options + ]); + }, + + /** + * APIMethod: clone + * Create a clone of this layer + * + * Parameters: + * obj - {Object} Is this ever used? + * + * Returns: + * {<OpenLayers.Layer.XYZ>} An exact clone of this OpenLayers.Layer.XYZ + */ + clone: function (obj) { + + if (obj == null) { + obj = new OpenLayers.Layer.XYZ(this.name, + this.url, + this.getOptions()); + } + + //get all additions from superclasses + obj = OpenLayers.Layer.Grid.prototype.clone.apply(this, [obj]); + + return obj; + }, + + /** + * Method: getURL + * + * Parameters: + * bounds - {<OpenLayers.Bounds>} + * + * Returns: + * {String} A string with the layer's url and parameters and also the + * passed-in bounds and appropriate tile size specified as + * parameters + */ + getURL: function (bounds) { + var xyz = this.getXYZ(bounds); + var url = this.url; + if (OpenLayers.Util.isArray(url)) { + var s = '' + xyz.x + xyz.y + xyz.z; + url = this.selectUrl(s, url); + } + + return OpenLayers.String.format(url, xyz); + }, + + /** + * Method: getXYZ + * Calculates x, y and z for the given bounds. + * + * Parameters: + * bounds - {<OpenLayers.Bounds>} + * + * Returns: + * {Object} - an object with x, y and z properties. + */ + getXYZ: function(bounds) { + var res = this.getServerResolution(); + var x = Math.round((bounds.left - this.maxExtent.left) / + (res * this.tileSize.w)); + var y = Math.round((this.maxExtent.top - bounds.top) / + (res * this.tileSize.h)); + var z = this.getServerZoom(); + + if (this.wrapDateLine) { + var limit = Math.pow(2, z); + x = ((x % limit) + limit) % limit; + } + + return {'x': x, 'y': y, 'z': z}; + }, + + /* APIMethod: setMap + * When the layer is added to a map, then we can fetch our origin + * (if we don't have one.) + * + * Parameters: + * map - {<OpenLayers.Map>} + */ + setMap: function(map) { + OpenLayers.Layer.Grid.prototype.setMap.apply(this, arguments); + if (!this.tileOrigin) { + this.tileOrigin = new OpenLayers.LonLat(this.maxExtent.left, + this.maxExtent.bottom); + } + }, + + CLASS_NAME: "OpenLayers.Layer.XYZ" +}); |