diff options
Diffstat (limited to 'misc/openlayers/lib/OpenLayers/Tile')
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Tile/Image.js | 510 | ||||
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Tile/Image/IFrame.js | 233 | ||||
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Tile/UTFGrid.js | 252 |
3 files changed, 0 insertions, 995 deletions
diff --git a/misc/openlayers/lib/OpenLayers/Tile/Image.js b/misc/openlayers/lib/OpenLayers/Tile/Image.js deleted file mode 100644 index 2fdffb3..0000000 --- a/misc/openlayers/lib/OpenLayers/Tile/Image.js +++ /dev/null @@ -1,510 +0,0 @@ -/* 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/Tile.js - * @requires OpenLayers/Animation.js - * @requires OpenLayers/Util.js - */ - -/** - * Class: OpenLayers.Tile.Image - * Instances of OpenLayers.Tile.Image are used to manage the image tiles - * used by various layers. Create a new image tile with the - * <OpenLayers.Tile.Image> constructor. - * - * Inherits from: - * - <OpenLayers.Tile> - */ -OpenLayers.Tile.Image = OpenLayers.Class(OpenLayers.Tile, { - - /** - * APIProperty: events - * {<OpenLayers.Events>} An events object that handles all - * events on the tile. - * - * Register a listener for a particular event with the following syntax: - * (code) - * tile.events.register(type, obj, listener); - * (end) - * - * Supported event types (in addition to the <OpenLayers.Tile> events): - * beforeload - Triggered before an image is prepared for loading, when the - * url for the image is known already. Listeners may call <setImage> on - * the tile instance. If they do so, that image will be used and no new - * one will be created. - */ - - /** - * APIProperty: url - * {String} The URL of the image being requested. No default. Filled in by - * layer.getURL() function. May be modified by loadstart listeners. - */ - url: null, - - /** - * Property: imgDiv - * {HTMLImageElement} The image for this tile. - */ - imgDiv: null, - - /** - * Property: frame - * {DOMElement} The image element is appended to the frame. Any gutter on - * the image will be hidden behind the frame. If no gutter is set, - * this will be null. - */ - frame: null, - - /** - * Property: imageReloadAttempts - * {Integer} Attempts to load the image. - */ - imageReloadAttempts: null, - - /** - * Property: layerAlphaHack - * {Boolean} True if the png alpha hack needs to be applied on the layer's div. - */ - layerAlphaHack: null, - - /** - * Property: asyncRequestId - * {Integer} ID of an request to see if request is still valid. This is a - * number which increments by 1 for each asynchronous request. - */ - asyncRequestId: null, - - /** - * APIProperty: maxGetUrlLength - * {Number} If set, requests that would result in GET urls with more - * characters than the number provided will be made using form-encoded - * HTTP POST. It is good practice to avoid urls that are longer than 2048 - * characters. - * - * Caution: - * Older versions of Gecko based browsers (e.g. Firefox < 3.5) and most - * Opera versions do not fully support this option. On all browsers, - * transition effects are not supported if POST requests are used. - */ - maxGetUrlLength: null, - - /** - * Property: canvasContext - * {CanvasRenderingContext2D} A canvas context associated with - * the tile image. - */ - canvasContext: null, - - /** - * APIProperty: crossOriginKeyword - * The value of the crossorigin keyword to use when loading images. This is - * only relevant when using <getCanvasContext> for tiles from remote - * origins and should be set to either 'anonymous' or 'use-credentials' - * for servers that send Access-Control-Allow-Origin headers with their - * tiles. - */ - crossOriginKeyword: null, - - /** TBD 3.0 - reorder the parameters to the init function to remove - * URL. the getUrl() function on the layer gets called on - * each draw(), so no need to specify it here. - */ - - /** - * Constructor: OpenLayers.Tile.Image - * Constructor for a new <OpenLayers.Tile.Image> instance. - * - * Parameters: - * layer - {<OpenLayers.Layer>} layer that the tile will go in. - * position - {<OpenLayers.Pixel>} - * bounds - {<OpenLayers.Bounds>} - * url - {<String>} Deprecated. Remove me in 3.0. - * size - {<OpenLayers.Size>} - * options - {Object} - */ - initialize: function(layer, position, bounds, url, size, options) { - OpenLayers.Tile.prototype.initialize.apply(this, arguments); - - this.url = url; //deprecated remove me - - this.layerAlphaHack = this.layer.alpha && OpenLayers.Util.alphaHack(); - - if (this.maxGetUrlLength != null || this.layer.gutter || this.layerAlphaHack) { - // only create frame if it's needed - this.frame = document.createElement("div"); - this.frame.style.position = "absolute"; - this.frame.style.overflow = "hidden"; - } - if (this.maxGetUrlLength != null) { - OpenLayers.Util.extend(this, OpenLayers.Tile.Image.IFrame); - } - }, - - /** - * APIMethod: destroy - * nullify references to prevent circular references and memory leaks - */ - destroy: function() { - if (this.imgDiv) { - this.clear(); - this.imgDiv = null; - this.frame = null; - } - // don't handle async requests any more - this.asyncRequestId = null; - OpenLayers.Tile.prototype.destroy.apply(this, arguments); - }, - - /** - * Method: draw - * Check that a tile should be drawn, and draw it. - * - * Returns: - * {Boolean} Was a tile drawn? Or null if a beforedraw listener returned - * false. - */ - draw: function() { - var shouldDraw = OpenLayers.Tile.prototype.draw.apply(this, arguments); - if (shouldDraw) { - // The layer's reproject option is deprecated. - if (this.layer != this.layer.map.baseLayer && this.layer.reproject) { - // getBoundsFromBaseLayer is defined in deprecated.js. - this.bounds = this.getBoundsFromBaseLayer(this.position); - } - if (this.isLoading) { - //if we're already loading, send 'reload' instead of 'loadstart'. - this._loadEvent = "reload"; - } else { - this.isLoading = true; - this._loadEvent = "loadstart"; - } - this.renderTile(); - this.positionTile(); - } else if (shouldDraw === false) { - this.unload(); - } - return shouldDraw; - }, - - /** - * Method: renderTile - * Internal function to actually initialize the image tile, - * position it correctly, and set its url. - */ - renderTile: function() { - if (this.layer.async) { - // Asynchronous image requests call the asynchronous getURL method - // on the layer to fetch an image that covers 'this.bounds'. - var id = this.asyncRequestId = (this.asyncRequestId || 0) + 1; - this.layer.getURLasync(this.bounds, function(url) { - if (id == this.asyncRequestId) { - this.url = url; - this.initImage(); - } - }, this); - } else { - // synchronous image requests get the url immediately. - this.url = this.layer.getURL(this.bounds); - this.initImage(); - } - }, - - /** - * Method: positionTile - * Using the properties currenty set on the layer, position the tile correctly. - * This method is used both by the async and non-async versions of the Tile.Image - * code. - */ - positionTile: function() { - var style = this.getTile().style, - size = this.frame ? this.size : - this.layer.getImageSize(this.bounds), - ratio = 1; - if (this.layer instanceof OpenLayers.Layer.Grid) { - ratio = this.layer.getServerResolution() / this.layer.map.getResolution(); - } - style.left = this.position.x + "px"; - style.top = this.position.y + "px"; - style.width = Math.round(ratio * size.w) + "px"; - style.height = Math.round(ratio * size.h) + "px"; - }, - - /** - * Method: clear - * Remove the tile from the DOM, clear it of any image related data so that - * it can be reused in a new location. - */ - clear: function() { - OpenLayers.Tile.prototype.clear.apply(this, arguments); - var img = this.imgDiv; - if (img) { - var tile = this.getTile(); - if (tile.parentNode === this.layer.div) { - this.layer.div.removeChild(tile); - } - this.setImgSrc(); - if (this.layerAlphaHack === true) { - img.style.filter = ""; - } - OpenLayers.Element.removeClass(img, "olImageLoadError"); - } - this.canvasContext = null; - }, - - /** - * Method: getImage - * Returns or creates and returns the tile image. - */ - getImage: function() { - if (!this.imgDiv) { - this.imgDiv = OpenLayers.Tile.Image.IMAGE.cloneNode(false); - - var style = this.imgDiv.style; - if (this.frame) { - var left = 0, top = 0; - if (this.layer.gutter) { - left = this.layer.gutter / this.layer.tileSize.w * 100; - top = this.layer.gutter / this.layer.tileSize.h * 100; - } - style.left = -left + "%"; - style.top = -top + "%"; - style.width = (2 * left + 100) + "%"; - style.height = (2 * top + 100) + "%"; - } - style.visibility = "hidden"; - style.opacity = 0; - if (this.layer.opacity < 1) { - style.filter = 'alpha(opacity=' + - (this.layer.opacity * 100) + - ')'; - } - style.position = "absolute"; - if (this.layerAlphaHack) { - // move the image out of sight - style.paddingTop = style.height; - style.height = "0"; - style.width = "100%"; - } - if (this.frame) { - this.frame.appendChild(this.imgDiv); - } - } - - return this.imgDiv; - }, - - /** - * APIMethod: setImage - * Sets the image element for this tile. This method should only be called - * from beforeload listeners. - * - * Parameters - * img - {HTMLImageElement} The image to use for this tile. - */ - setImage: function(img) { - this.imgDiv = img; - }, - - /** - * Method: initImage - * Creates the content for the frame on the tile. - */ - initImage: function() { - if (!this.url && !this.imgDiv) { - // fast path out - if there is no tile url and no previous image - this.isLoading = false; - return; - } - this.events.triggerEvent('beforeload'); - this.layer.div.appendChild(this.getTile()); - this.events.triggerEvent(this._loadEvent); - var img = this.getImage(); - var src = img.getAttribute('src') || ''; - if (this.url && OpenLayers.Util.isEquivalentUrl(src, this.url)) { - this._loadTimeout = window.setTimeout( - OpenLayers.Function.bind(this.onImageLoad, this), 0 - ); - } else { - this.stopLoading(); - if (this.crossOriginKeyword) { - img.removeAttribute("crossorigin"); - } - OpenLayers.Event.observe(img, "load", - OpenLayers.Function.bind(this.onImageLoad, this) - ); - OpenLayers.Event.observe(img, "error", - OpenLayers.Function.bind(this.onImageError, this) - ); - this.imageReloadAttempts = 0; - this.setImgSrc(this.url); - } - }, - - /** - * Method: setImgSrc - * Sets the source for the tile image - * - * Parameters: - * url - {String} or undefined to hide the image - */ - setImgSrc: function(url) { - var img = this.imgDiv; - if (url) { - img.style.visibility = 'hidden'; - img.style.opacity = 0; - // don't set crossOrigin if the url is a data URL - if (this.crossOriginKeyword) { - if (url.substr(0, 5) !== 'data:') { - img.setAttribute("crossorigin", this.crossOriginKeyword); - } else { - img.removeAttribute("crossorigin"); - } - } - img.src = url; - } else { - // Remove reference to the image, and leave it to the browser's - // caching and garbage collection. - this.stopLoading(); - this.imgDiv = null; - if (img.parentNode) { - img.parentNode.removeChild(img); - } - } - }, - - /** - * Method: getTile - * Get the tile's markup. - * - * Returns: - * {DOMElement} The tile's markup - */ - getTile: function() { - return this.frame ? this.frame : this.getImage(); - }, - - /** - * Method: createBackBuffer - * Create a backbuffer for this tile. A backbuffer isn't exactly a clone - * of the tile's markup, because we want to avoid the reloading of the - * image. So we clone the frame, and steal the image from the tile. - * - * Returns: - * {DOMElement} The markup, or undefined if the tile has no image - * or if it's currently loading. - */ - createBackBuffer: function() { - if (!this.imgDiv || this.isLoading) { - return; - } - var backBuffer; - if (this.frame) { - backBuffer = this.frame.cloneNode(false); - backBuffer.appendChild(this.imgDiv); - } else { - backBuffer = this.imgDiv; - } - this.imgDiv = null; - return backBuffer; - }, - - /** - * Method: onImageLoad - * Handler for the image onload event - */ - onImageLoad: function() { - var img = this.imgDiv; - this.stopLoading(); - img.style.visibility = 'inherit'; - img.style.opacity = this.layer.opacity; - this.isLoading = false; - this.canvasContext = null; - this.events.triggerEvent("loadend"); - - if (this.layerAlphaHack === true) { - img.style.filter = - "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + - img.src + "', sizingMethod='scale')"; - } - }, - - /** - * Method: onImageError - * Handler for the image onerror event - */ - onImageError: function() { - var img = this.imgDiv; - if (img.src != null) { - this.imageReloadAttempts++; - if (this.imageReloadAttempts <= OpenLayers.IMAGE_RELOAD_ATTEMPTS) { - this.setImgSrc(this.layer.getURL(this.bounds)); - } else { - OpenLayers.Element.addClass(img, "olImageLoadError"); - this.events.triggerEvent("loaderror"); - this.onImageLoad(); - } - } - }, - - /** - * Method: stopLoading - * Stops a loading sequence so <onImageLoad> won't be executed. - */ - stopLoading: function() { - OpenLayers.Event.stopObservingElement(this.imgDiv); - window.clearTimeout(this._loadTimeout); - delete this._loadTimeout; - }, - - /** - * APIMethod: getCanvasContext - * Returns a canvas context associated with the tile image (with - * the image drawn on it). - * Returns undefined if the browser does not support canvas, if - * the tile has no image or if it's currently loading. - * - * The function returns a canvas context instance but the - * underlying canvas is still available in the 'canvas' property: - * (code) - * var context = tile.getCanvasContext(); - * if (context) { - * var data = context.canvas.toDataURL('image/jpeg'); - * } - * (end) - * - * Returns: - * {Boolean} - */ - getCanvasContext: function() { - if (OpenLayers.CANVAS_SUPPORTED && this.imgDiv && !this.isLoading) { - if (!this.canvasContext) { - var canvas = document.createElement("canvas"); - canvas.width = this.size.w; - canvas.height = this.size.h; - this.canvasContext = canvas.getContext("2d"); - this.canvasContext.drawImage(this.imgDiv, 0, 0); - } - return this.canvasContext; - } - }, - - CLASS_NAME: "OpenLayers.Tile.Image" - -}); - -/** - * Constant: OpenLayers.Tile.Image.IMAGE - * {HTMLImageElement} The image for a tile. - */ -OpenLayers.Tile.Image.IMAGE = (function() { - var img = new Image(); - img.className = "olTileImage"; - // avoid image gallery menu in IE6 - img.galleryImg = "no"; - return img; -}()); - diff --git a/misc/openlayers/lib/OpenLayers/Tile/Image/IFrame.js b/misc/openlayers/lib/OpenLayers/Tile/Image/IFrame.js deleted file mode 100644 index 9e33acc..0000000 --- a/misc/openlayers/lib/OpenLayers/Tile/Image/IFrame.js +++ /dev/null @@ -1,233 +0,0 @@ -/* 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/Tile/Image.js - */ - -/** - * Constant: OpenLayers.Tile.Image.IFrame - * Mixin for tiles that use form-encoded POST requests to get images from - * remote services. Images will be loaded using HTTP-POST into an IFrame. - * - * This mixin will be applied to <OpenLayers.Tile.Image> instances - * configured with <OpenLayers.Tile.Image.maxGetUrlLength> set. - */ -OpenLayers.Tile.Image.IFrame = { - - /** - * Property: useIFrame - * {Boolean} true if we are currently using an IFrame to render POST - * responses, false if we are using an img element to render GET responses. - */ - useIFrame: null, - - /** - * Property: blankImageUrl - * {String} Using a data scheme url is not supported by all browsers, but - * we don't care because we either set it as css backgroundImage, or the - * image's display style is set to "none" when we use it. - */ - blankImageUrl: "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAQAIBRAA7", - - /** - * Method: draw - * Set useIFrame in the instance, and operate the image/iframe switch. - * Then call Tile.Image.draw. - * - * Returns: - * {Boolean} - */ - draw: function() { - var draw = OpenLayers.Tile.Image.prototype.shouldDraw.call(this); - if(draw) { - - // this.url isn't set to the currect value yet, so we call getURL - // on the layer and store the result in a local variable - var url = this.layer.getURL(this.bounds); - - var usedIFrame = this.useIFrame; - this.useIFrame = this.maxGetUrlLength !== null && - !this.layer.async && - url.length > this.maxGetUrlLength; - - var fromIFrame = usedIFrame && !this.useIFrame; - var toIFrame = !usedIFrame && this.useIFrame; - - if(fromIFrame || toIFrame) { - - // Switching between GET (image) and POST (iframe). - - // We remove the imgDiv (really either an image or an iframe) - // from the frame and set it to null to make sure initImage - // will call getImage. - - if(this.imgDiv && this.imgDiv.parentNode === this.frame) { - this.frame.removeChild(this.imgDiv); - } - this.imgDiv = null; - - // And if we had an iframe we also remove the event pane. - - if(fromIFrame) { - this.frame.removeChild(this.frame.firstChild); - } - } - } - return OpenLayers.Tile.Image.prototype.draw.apply(this, arguments); - }, - - /** - * Method: getImage - * Creates the content for the frame on the tile. - */ - getImage: function() { - if (this.useIFrame === true) { - if (!this.frame.childNodes.length) { - var eventPane = document.createElement("div"), - style = eventPane.style; - style.position = "absolute"; - style.width = "100%"; - style.height = "100%"; - style.zIndex = 1; - style.backgroundImage = "url(" + this.blankImageUrl + ")"; - this.frame.appendChild(eventPane); - } - - var id = this.id + '_iFrame', iframe; - if (parseFloat(navigator.appVersion.split("MSIE")[1]) < 9) { - // Older IE versions do not set the name attribute of an iFrame - // properly via DOM manipulation, so we need to do it on our own with - // this hack. - iframe = document.createElement('<iframe name="'+id+'">'); - - // IFrames in older IE versions are not transparent, if you set - // the backgroundColor transparent. This is a workaround to get - // transparent iframes. - iframe.style.backgroundColor = '#FFFFFF'; - iframe.style.filter = 'chroma(color=#FFFFFF)'; - } - else { - iframe = document.createElement('iframe'); - iframe.style.backgroundColor = 'transparent'; - - // iframe.name needs to be an unique id, otherwise it - // could happen that other iframes are overwritten. - iframe.name = id; - } - - // some special properties to avoid scaling the images and scrollbars - // in the iframe - iframe.scrolling = 'no'; - iframe.marginWidth = '0px'; - iframe.marginHeight = '0px'; - iframe.frameBorder = '0'; - - iframe.style.position = "absolute"; - iframe.style.width = "100%"; - iframe.style.height = "100%"; - - if (this.layer.opacity < 1) { - OpenLayers.Util.modifyDOMElement(iframe, null, null, null, - null, null, null, this.layer.opacity); - } - this.frame.appendChild(iframe); - this.imgDiv = iframe; - return iframe; - } else { - return OpenLayers.Tile.Image.prototype.getImage.apply(this, arguments); - } - }, - - /** - * Method: createRequestForm - * Create the html <form> element with width, height, bbox and all - * parameters specified in the layer params. - * - * Returns: - * {DOMElement} The form element which sends the HTTP-POST request to the - * WMS. - */ - createRequestForm: function() { - // creation of the form element - var form = document.createElement('form'); - form.method = 'POST'; - var cacheId = this.layer.params["_OLSALT"]; - cacheId = (cacheId ? cacheId + "_" : "") + this.bounds.toBBOX(); - form.action = OpenLayers.Util.urlAppend(this.layer.url, cacheId); - form.target = this.id + '_iFrame'; - - // adding all parameters in layer params as hidden fields to the html - // form element - var imageSize = this.layer.getImageSize(), - params = OpenLayers.Util.getParameters(this.url), - field; - - for(var par in params) { - field = document.createElement('input'); - field.type = 'hidden'; - field.name = par; - field.value = params[par]; - form.appendChild(field); - } - - return form; - }, - - /** - * Method: setImgSrc - * Sets the source for the tile image - * - * Parameters: - * url - {String} - */ - setImgSrc: function(url) { - if (this.useIFrame === true) { - if (url) { - var form = this.createRequestForm(); - this.frame.appendChild(form); - form.submit(); - this.frame.removeChild(form); - } else if (this.imgDiv.parentNode === this.frame) { - // we don't reuse iframes to avoid caching issues - this.frame.removeChild(this.imgDiv); - this.imgDiv = null; - } - } else { - OpenLayers.Tile.Image.prototype.setImgSrc.apply(this, arguments); - } - }, - - /** - * Method: onImageLoad - * Handler for the image onload event - */ - onImageLoad: function() { - //TODO de-uglify opacity handling - OpenLayers.Tile.Image.prototype.onImageLoad.apply(this, arguments); - if (this.useIFrame === true) { - this.imgDiv.style.opacity = 1; - this.frame.style.opacity = this.layer.opacity; - } - }, - - /** - * Method: createBackBuffer - * Override createBackBuffer to do nothing when we use an iframe. Moving an - * iframe from one element to another makes it necessary to reload the iframe - * because its content is lost. So we just give up. - * - * Returns: - * {DOMElement} - */ - createBackBuffer: function() { - var backBuffer; - if(this.useIFrame === false) { - backBuffer = OpenLayers.Tile.Image.prototype.createBackBuffer.call(this); - } - return backBuffer; - } -}; diff --git a/misc/openlayers/lib/OpenLayers/Tile/UTFGrid.js b/misc/openlayers/lib/OpenLayers/Tile/UTFGrid.js deleted file mode 100644 index 2836ee0..0000000 --- a/misc/openlayers/lib/OpenLayers/Tile/UTFGrid.js +++ /dev/null @@ -1,252 +0,0 @@ -/* 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/Tile.js - * @requires OpenLayers/Format/JSON.js - * @requires OpenLayers/Request.js - */ - -/** - * Class: OpenLayers.Tile.UTFGrid - * Instances of OpenLayers.Tile.UTFGrid are used to manage - * UTFGrids. This is an unusual tile type in that it doesn't have a - * rendered image; only a 'hit grid' that can be used to - * look up feature attributes. - * - * See the <OpenLayers.Tile.UTFGrid> constructor for details on constructing a - * new instance. - * - * Inherits from: - * - <OpenLayers.Tile> - */ -OpenLayers.Tile.UTFGrid = OpenLayers.Class(OpenLayers.Tile, { - - /** - * Property: url - * {String} - * The URL of the UTFGrid file being requested. Provided by the <getURL> - * method. - */ - url: null, - - /** - * Property: utfgridResolution - * {Number} - * Ratio of the pixel width to the width of a UTFGrid data point. If an - * entry in the grid represents a 4x4 block of pixels, the - * utfgridResolution would be 4. Default is 2. - */ - utfgridResolution: 2, - - /** - * Property: json - * {Object} - * Stores the parsed JSON tile data structure. - */ - json: null, - - /** - * Property: format - * {OpenLayers.Format.JSON} - * Parser instance used to parse JSON for cross browser support. The native - * JSON.parse method will be used where available (all except IE<8). - */ - format: null, - - /** - * Constructor: OpenLayers.Tile.UTFGrid - * Constructor for a new <OpenLayers.Tile.UTFGrid> instance. - * - * Parameters: - * layer - {<OpenLayers.Layer>} layer that the tile will go in. - * position - {<OpenLayers.Pixel>} - * bounds - {<OpenLayers.Bounds>} - * url - {<String>} Deprecated. Remove me in 3.0. - * size - {<OpenLayers.Size>} - * options - {Object} - */ - - /** - * APIMethod: destroy - * Clean up. - */ - destroy: function() { - this.clear(); - OpenLayers.Tile.prototype.destroy.apply(this, arguments); - }, - - /** - * Method: draw - * Check that a tile should be drawn, and draw it. - * In the case of UTFGrids, "drawing" it means fetching and - * parsing the json. - * - * Returns: - * {Boolean} Was a tile drawn? - */ - draw: function() { - var drawn = OpenLayers.Tile.prototype.draw.apply(this, arguments); - if (drawn) { - if (this.isLoading) { - this.abortLoading(); - //if we're already loading, send 'reload' instead of 'loadstart'. - this.events.triggerEvent("reload"); - } else { - this.isLoading = true; - this.events.triggerEvent("loadstart"); - } - this.url = this.layer.getURL(this.bounds); - - if (this.layer.useJSONP) { - // Use JSONP method to avoid xbrowser policy - var ols = new OpenLayers.Protocol.Script({ - url: this.url, - callback: function(response) { - this.isLoading = false; - this.events.triggerEvent("loadend"); - this.json = response.data; - }, - scope: this - }); - ols.read(); - this.request = ols; - } else { - // Use standard XHR - this.request = OpenLayers.Request.GET({ - url: this.url, - callback: function(response) { - this.isLoading = false; - this.events.triggerEvent("loadend"); - if (response.status === 200) { - this.parseData(response.responseText); - } - }, - scope: this - }); - } - } else { - this.unload(); - } - return drawn; - }, - - /** - * Method: abortLoading - * Cancel a pending request. - */ - abortLoading: function() { - if (this.request) { - this.request.abort(); - delete this.request; - } - this.isLoading = false; - }, - - /** - * Method: getFeatureInfo - * Get feature information associated with a pixel offset. If the pixel - * offset corresponds to a feature, the returned object will have id - * and data properties. Otherwise, null will be returned. - * - * - * Parameters: - * i - {Number} X-axis pixel offset (from top left of tile) - * j - {Number} Y-axis pixel offset (from top left of tile) - * - * Returns: - * {Object} Object with feature id and data properties corresponding to the - * given pixel offset. - */ - getFeatureInfo: function(i, j) { - var info = null; - if (this.json) { - var id = this.getFeatureId(i, j); - if (id !== null) { - info = {id: id, data: this.json.data[id]}; - } - } - return info; - }, - - /** - * Method: getFeatureId - * Get the identifier for the feature associated with a pixel offset. - * - * Parameters: - * i - {Number} X-axis pixel offset (from top left of tile) - * j - {Number} Y-axis pixel offset (from top left of tile) - * - * Returns: - * {Object} The feature identifier corresponding to the given pixel offset. - * Returns null if pixel doesn't correspond to a feature. - */ - getFeatureId: function(i, j) { - var id = null; - if (this.json) { - var resolution = this.utfgridResolution; - var row = Math.floor(j / resolution); - var col = Math.floor(i / resolution); - var charCode = this.json.grid[row].charCodeAt(col); - var index = this.indexFromCharCode(charCode); - var keys = this.json.keys; - if (!isNaN(index) && (index in keys)) { - id = keys[index]; - } - } - return id; - }, - - /** - * Method: indexFromCharCode - * Given a character code for one of the UTFGrid "grid" characters, - * resolve the integer index for the feature id in the UTFGrid "keys" - * array. - * - * Parameters: - * charCode - {Integer} - * - * Returns: - * {Integer} Index for the feature id from the keys array. - */ - indexFromCharCode: function(charCode) { - if (charCode >= 93) { - charCode--; - } - if (charCode >= 35) { - charCode --; - } - return charCode - 32; - }, - - /** - * Method: parseData - * Parse the JSON from a request - * - * Parameters: - * str - {String} UTFGrid as a JSON string. - * - * Returns: - * {Object} parsed javascript data - */ - parseData: function(str) { - if (!this.format) { - this.format = new OpenLayers.Format.JSON(); - } - this.json = this.format.read(str); - }, - - /** - * Method: clear - * Delete data stored with this tile. - */ - clear: function() { - this.json = null; - }, - - CLASS_NAME: "OpenLayers.Tile.UTFGrid" - -}); |