/* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for
* full list of contributors). Published under the Clear BSD license.
* See http://svn.openlayers.org/trunk/openlayers/license.txt for the
* full text of the license. */
/**
* @requires OpenLayers/Layer/Grid.js
* @requires OpenLayers/Tile/Image.js
*/
/**
* Class: OpenLayers.Layer.TMS
*
* Inherits from:
* - <OpenLayers.Layer.Grid>
*/
OpenLayers.Layer.TMS = OpenLayers.Class(OpenLayers.Layer.Grid, {
/**
* APIProperty: serviceVersion
* {String}
*/
serviceVersion: "1.0.0",
/**
* APIProperty: isBaseLayer
* {Boolean}
*/
isBaseLayer: true,
/**
* APIProperty: tileOrigin
* {<OpenLayers.Pixel>}
*/
tileOrigin: null,
/**
* APIProperty: serverResolutions
* {Array} A list of all resolutions available on the server. Only set this
* property if the map resolutions differs from the server.
*/
serverResolutions: null,
/**
* 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,
/**
* Constructor: OpenLayers.Layer.TMS
*
* Parameters:
* name - {String}
* url - {String}
* options - {Object} Hashtable of extra options to tag onto the layer
*/
initialize: function(name, url, options) {
var newArguments = [];
newArguments.push(name, url, {}, options);
OpenLayers.Layer.Grid.prototype.initialize.apply(this, newArguments);
},
/**
* APIMethod:destroy
*/
destroy: function() {
// for now, nothing special to do here.
OpenLayers.Layer.Grid.prototype.destroy.apply(this, arguments);
},
/**
* APIMethod: clone
*
* Parameters:
* obj - {Object}
*
* Returns:
* {<OpenLayers.Layer.TMS>} An exact clone of this <OpenLayers.Layer.TMS>
*/
clone: function (obj) {
if (obj == null) {
obj = new OpenLayers.Layer.TMS(this.name,
this.url,
this.getOptions());
}
//get all additions from superclasses
obj = OpenLayers.Layer.Grid.prototype.clone.apply(this, [obj]);
// copy/set any non-init, non-simple values here
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) {
bounds = this.adjustBounds(bounds);
var res = this.map.getResolution();
var x = Math.round((bounds.left - this.tileOrigin.lon) / (res * this.tileSize.w));
var y = Math.round((bounds.bottom - this.tileOrigin.lat) / (res * this.tileSize.h));
var z = this.serverResolutions != null ?
OpenLayers.Util.indexOf(this.serverResolutions, res) :
this.map.getZoom() + this.zoomOffset;
var path = this.serviceVersion + "/" + this.layername + "/" + z + "/" + x + "/" + y + "." + this.type;
var url = this.url;
if (url instanceof Array) {
url = this.selectUrl(path, url);
}
return url + path;
},
/**
* Method: addTile
* addTile creates a tile, initializes it, and adds it to the layer div.
*
* Parameters:
* bounds - {<OpenLayers.Bounds>}
* position - {<OpenLayers.Pixel>}
*
* Returns:
* {<OpenLayers.Tile.Image>} The added OpenLayers.Tile.Image
*/
addTile:function(bounds,position) {
return new OpenLayers.Tile.Image(this, position, bounds,
null, this.tileSize);
},
/**
* 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.map.maxExtent.left,
this.map.maxExtent.bottom);
}
},
CLASS_NAME: "OpenLayers.Layer.TMS"
});