--- a/labs/openlayers/lib/OpenLayers/Layer/WMS.js +++ b/labs/openlayers/lib/OpenLayers/Layer/WMS.js @@ -1,1 +1,269 @@ - +/* 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.WMS + * Instances of OpenLayers.Layer.WMS are used to display data from OGC Web + * Mapping Services. Create a new WMS layer with the <OpenLayers.Layer.WMS> + * constructor. + * + * Inherits from: + * - <OpenLayers.Layer.Grid> + */ +OpenLayers.Layer.WMS = OpenLayers.Class(OpenLayers.Layer.Grid, { + + /** + * Constant: DEFAULT_PARAMS + * {Object} Hashtable of default parameter key/value pairs + */ + DEFAULT_PARAMS: { service: "WMS", + version: "1.1.1", + request: "GetMap", + styles: "", + exceptions: "application/vnd.ogc.se_inimage", + format: "image/jpeg" + }, + + /** + * Property: reproject + * *Deprecated*. See http://trac.openlayers.org/wiki/SphericalMercator + * for information on the replacement for this functionality. + * {Boolean} Try to reproject this layer if its coordinate reference system + * is different than that of the base layer. Default is true. + * Set this in the layer options. Should be set to false in + * most cases. + */ + reproject: false, + + /** + * APIProperty: isBaseLayer + * {Boolean} Default is true for WMS layer + */ + isBaseLayer: true, + + /** + * APIProperty: encodeBBOX + * {Boolean} Should the BBOX commas be encoded? The WMS spec says 'no', + * but some services want it that way. Default false. + */ + encodeBBOX: false, + + /** + * APIProperty: noMagic + * {Boolean} If true, the image format will not be automagicaly switched + * from image/jpeg to image/png or image/gif when using + * TRANSPARENT=TRUE. Also isBaseLayer will not changed by the + * constructor. Default false. + */ + noMagic: false, + + /** + * Property: yx + * {Object} Keys in this object are EPSG codes for which the axis order + * is to be reversed (yx instead of xy, LatLon instead of LonLat), with + * true as value. This is only relevant for WMS versions >= 1.3.0. + */ + yx: {'EPSG:4326': true}, + + /** + * Constructor: OpenLayers.Layer.WMS + * Create a new WMS layer object + * + * Example: + * (code) + * var wms = new OpenLayers.Layer.WMS("NASA Global Mosaic", + * "http://wms.jpl.nasa.gov/wms.cgi", + * {layers: "modis,global_mosaic"}); + * (end) + * + * Parameters: + * name - {String} A name for the layer + * url - {String} Base url for the WMS + * (e.g. http://wms.jpl.nasa.gov/wms.cgi) + * params - {Object} An object with key/value pairs representing the + * GetMap query string parameters and parameter values. + * options - {Ojbect} Hashtable of extra options to tag onto the layer + */ + initialize: function(name, url, params, options) { + var newArguments = []; + //uppercase params + params = OpenLayers.Util.upperCaseObject(params); + if (parseFloat(params.VERSION) >= 1.3 && !params.EXCEPTIONS) { + params.EXCEPTIONS = "INIMAGE"; + } + newArguments.push(name, url, params, options); + OpenLayers.Layer.Grid.prototype.initialize.apply(this, newArguments); + OpenLayers.Util.applyDefaults( + this.params, + OpenLayers.Util.upperCaseObject(this.DEFAULT_PARAMS) + ); + + + //layer is transparent + if (!this.noMagic && this.params.TRANSPARENT && + this.params.TRANSPARENT.toString().toLowerCase() == "true") { + + // unless explicitly set in options, make layer an overlay + if ( (options == null) || (!options.isBaseLayer) ) { + this.isBaseLayer = false; + } + + // jpegs can never be transparent, so intelligently switch the + // format, depending on teh browser's capabilities + if (this.params.FORMAT == "image/jpeg") { + this.params.FORMAT = OpenLayers.Util.alphaHack() ? "image/gif" + : "image/png"; + } + } + + }, + + /** + * Method: destroy + * Destroy this layer + */ + destroy: function() { + // for now, nothing special to do here. + OpenLayers.Layer.Grid.prototype.destroy.apply(this, arguments); + }, + + + /** + * Method: clone + * Create a clone of this layer + * + * Returns: + * {<OpenLayers.Layer.WMS>} An exact clone of this layer + */ + clone: function (obj) { + + if (obj == null) { + obj = new OpenLayers.Layer.WMS(this.name, + this.url, + this.params, + 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; + }, + + /** + * APIMethod: reverseAxisOrder + * Returns true if the axis order is reversed for the WMS version and + * projection of the layer. + * + * Returns: + * {Boolean} true if the axis order is reversed, false otherwise. + */ + reverseAxisOrder: function() { + return (parseFloat(this.params.VERSION) >= 1.3 && + !!this.yx[this.map.getProjectionObject().getCode()]); + }, + + /** + * Method: getURL + * Return a GetMap query string for this layer + * + * Parameters: + * bounds - {<OpenLayers.Bounds>} A bounds representing the bbox for the + * request. + * + * 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 imageSize = this.getImageSize(); + var newParams = {}; + // WMS 1.3 introduced axis order + var reverseAxisOrder = this.reverseAxisOrder(); + newParams.BBOX = this.encodeBBOX ? + bounds.toBBOX(null, reverseAxisOrder) : + bounds.toArray(reverseAxisOrder); + newParams.WIDTH = imageSize.w; + newParams.HEIGHT = imageSize.h; + var requestString = this.getFullRequestString(newParams); + return requestString; + }, + + /** + * 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: mergeNewParams + * Catch changeParams and uppercase the new params to be merged in + * before calling changeParams on the super class. + * + * Once params have been changed, the tiles will be reloaded with + * the new parameters. + * + * Parameters: + * newParams - {Object} Hashtable of new params to use + */ + mergeNewParams:function(newParams) { + var upperParams = OpenLayers.Util.upperCaseObject(newParams); + var newArguments = [upperParams]; + return OpenLayers.Layer.Grid.prototype.mergeNewParams.apply(this, + newArguments); + }, + + /** + * APIMethod: getFullRequestString + * Combine the layer's url with its params and these newParams. + * + * Add the SRS parameter from projection -- this is probably + * more eloquently done via a setProjection() method, but this + * works for now and always. + * + * Parameters: + * newParams - {Object} + * altUrl - {String} Use this as the url instead of the layer's url + * + * Returns: + * {String} + */ + getFullRequestString:function(newParams, altUrl) { + var projectionCode = this.map.getProjection(); + var value = (projectionCode == "none") ? null : projectionCode + if (parseFloat(this.params.VERSION) >= 1.3) { + this.params.CRS = value; + } else { + this.params.SRS = value; + } + + return OpenLayers.Layer.Grid.prototype.getFullRequestString.apply( + this, arguments); + }, + + CLASS_NAME: "OpenLayers.Layer.WMS" +}); +