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3032
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perry
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/* Copyright (c) 2006 MetaCarta, Inc., published under the BSD license.
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* See http://svn.openlayers.org/trunk/openlayers/license.txt for the full
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* text of the license. */
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/**
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* @class
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*/
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OpenLayers.Util = new Object();
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/**
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* @param {String} id
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* @param {OpenLayers.Pixel} px
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* @param {OpenLayers.Size} sz
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* @param {String} position
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* @param {String} border
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* @param {String} overflow
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*/
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OpenLayers.Util.modifyDOMElement = function(element, id, px, sz, position,
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border, overflow) {
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if (id) {
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element.id = id;
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}
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if (px) {
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element.style.left = px.x + "px";
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element.style.top = px.y + "px";
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}
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if (sz) {
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element.style.width = sz.w + "px";
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element.style.height = sz.h + "px";
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}
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if (position) {
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element.style.position = position;
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}
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if (border) {
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element.style.border = border;
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}
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if (overflow) {
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element.style.overflow = overflow;
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}
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};
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/**
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* zIndex is NOT set
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*
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* @param {String} id
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* @param {OpenLayers.Pixel} px
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* @param {OpenLayers.Size} sz
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* @param {String} imgURL
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* @param {String} position
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* @param {String} border
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* @param {String} overflow
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*
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* @returns A DOM Div created with the specified attributes.
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* @type DOMElement
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*/
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OpenLayers.Util.createDiv = function(id, px, sz, imgURL, position,
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border, overflow) {
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var dom = document.createElement('div');
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//set specific properties
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dom.style.padding = "0";
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dom.style.margin = "0";
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if (imgURL) {
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dom.style.backgroundImage = 'url(' + imgURL + ')';
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}
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//set generic properties
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if (!id) {
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id = OpenLayers.Util.createUniqueID("OpenLayersDiv");
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}
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if (!position) {
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position = "absolute";
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}
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OpenLayers.Util.modifyDOMElement(dom, id, px, sz,
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position, border, overflow);
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return dom;
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};
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/**
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* @param {String} id
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* @param {OpenLayers.Pixel} px
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* @param {OpenLayers.Size} sz
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* @param {String} imgURL
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* @param {String} position
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* @param {String} border
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* @param {Boolean} delayDisplay
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*
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* @returns A DOM Image created with the specified attributes.
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* @type DOMElement
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*/
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OpenLayers.Util.createImage = function(id, px, sz, imgURL, position, border,
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delayDisplay) {
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image = document.createElement("img");
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if(delayDisplay) {
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image.style.display = "none";
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Event.observe(image, "load",
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OpenLayers.Util.onImageLoad.bindAsEventListener(image));
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Event.observe(image, "error",
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OpenLayers.Util.onImageLoadError.bindAsEventListener(image));
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}
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//set special properties
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image.style.alt = id;
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image.galleryImg = "no";
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if (imgURL) {
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image.src = imgURL;
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}
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//set generic properties
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if (!id) {
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id = OpenLayers.Util.createUniqueID("OpenLayersDiv");
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}
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if (!position) {
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position = "relative";
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}
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OpenLayers.Util.modifyDOMElement(image, id, px, sz, position, border);
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return image;
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};
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OpenLayers.Util.onImageLoad = function() {
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this.style.backgroundColor = null;
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this.style.display = "";
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};
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OpenLayers.Util.onImageLoadError = function() {
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this.style.backgroundColor = "pink";
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};
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OpenLayers.Util.alphaHack = function() {
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var arVersion = navigator.appVersion.split("MSIE");
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var version = parseFloat(arVersion[1]);
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return ( (document.body.filters) &&
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(version >= 5.5) && (version < 7) );
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}
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/**
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* @param {DOMElement} div Div containing Alpha-adjusted Image
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* @param {String} id
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* @param {OpenLayers.Pixel} px
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* @param {OpenLayers.Size} sz
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* @param {String} imgURL
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* @param {String} position
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* @param {String} border
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* @param {String} sizing 'crop', 'scale', or 'image'. Default is "scale"
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*/
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OpenLayers.Util.modifyAlphaImageDiv = function(div, id, px, sz, imgURL,
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position, border, sizing) {
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OpenLayers.Util.modifyDOMElement(div, id, px, sz);
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var img = div.childNodes[0];
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if (imgURL) {
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img.src = imgURL;
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}
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OpenLayers.Util.modifyDOMElement(img, div.id + "_innerImage", null, sz,
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"relative", border);
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if (OpenLayers.Util.alphaHack()) {
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div.style.display = "inline-block";
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if (sizing == null) {
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sizing = "scale";
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}
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div.style.filter = "progid:DXImageTransform.Microsoft" +
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".AlphaImageLoader(src='" + img.src + "', " +
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"sizingMethod='" + sizing + "')";
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img.style.filter = "progid:DXImageTransform.Microsoft" +
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".Alpha(opacity=0)";
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}
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};
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/**
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* @param {String} id
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* @param {OpenLayers.Pixel} px
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* @param {OpenLayers.Size} sz
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* @param {String} imgURL
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* @param {String} position
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* @param {String} border
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* @param {String} sizing 'crop', 'scale', or 'image'. Default is "scale"
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* @param {Boolean} delayDisplay
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*
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* @returns A DOM Div created with a DOM Image inside it. If the hack is
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* needed for transparency in IE, it is added.
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* @type DOMElement
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*/
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OpenLayers.Util.createAlphaImageDiv = function(id, px, sz, imgURL,
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position, border, sizing, delayDisplay) {
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var div = OpenLayers.Util.createDiv();
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var img = OpenLayers.Util.createImage(null, null, null, null, null, null,
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false);
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div.appendChild(img);
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if (delayDisplay) {
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img.style.display = "none";
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Event.observe(img, "load",
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OpenLayers.Util.onImageLoad.bindAsEventListener(div));
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Event.observe(img, "error",
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OpenLayers.Util.onImageLoadError.bindAsEventListener(div));
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}
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OpenLayers.Util.modifyAlphaImageDiv(div, id, px, sz, imgURL,
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position, border, sizing);
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return div;
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};
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/** Creates a new hashtable and copies over all the keys from the
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* passed-in object, but storing them under an uppercased
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* version of the key at which they were stored.
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*
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* @param {Object} object
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*
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* @returns A new Object with all the same keys but uppercased
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* @type Object
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*/
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OpenLayers.Util.upperCaseObject = function (object) {
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var uObject = new Object();
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for (var key in object) {
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uObject[key.toUpperCase()] = object[key];
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}
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return uObject;
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};
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/** Takes a hashtable and copies any keys that don't exist from
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* another hashtable, by analogy with Object.extend() from
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* Prototype.js.
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*
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* @param {Object} to
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* @param {Object} from
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*/
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OpenLayers.Util.applyDefaults = function (to, from) {
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for (var key in from) {
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if (to[key] == null) {
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to[key] = from[key];
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}
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}
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};
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/**
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* @param {Object} params
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*
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* @returns a concatenation of the properties of an object in
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* http parameter notation.
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* (ex. <i>"key1=value1&key2=value2&key3=value3"</i>)
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* @type String
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*/
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OpenLayers.Util.getParameterString = function(params) {
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paramsArray = new Array();
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for (var key in params) {
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var value = params[key];
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if ((value != null) && (typeof value != 'function')) {
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paramsArray.push(key + "=" + value);
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}
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}
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return paramsArray.join("&");
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};
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/**
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* @returns The fully formatted image location string
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* @type String
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*/
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OpenLayers.Util.getImagesLocation = function() {
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return OpenLayers._getScriptLocation() + "img/";
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};
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/** These could/should be made namespace aware?
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*
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* @param {} p
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* @param {str} tagName
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*
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* @return {Array}
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*/
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OpenLayers.Util.getNodes=function(p, tagName) {
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var nodes = Try.these(
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function () {
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return OpenLayers.Util._getNodes(p.documentElement.childNodes,
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tagName);
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},
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function () {
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return OpenLayers.Util._getNodes(p.childNodes, tagName);
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}
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);
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return nodes;
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};
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/**
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* @param {Array} nodes
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* @param {str} tagName
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*
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* @return {Array}
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*/
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OpenLayers.Util._getNodes=function(nodes, tagName) {
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var retArray = new Array();
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for (var i=0;i<nodes.length;i++) {
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if (nodes[i].nodeName==tagName) {
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retArray.push(nodes[i]);
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}
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}
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return retArray;
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};
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/**
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* @param {} parent
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* @param {str} item
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* @param {int} index
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*
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* @return {str}
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*/
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OpenLayers.Util.getTagText = function (parent, item, index) {
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var result = OpenLayers.Util.getNodes(parent, item);
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if (result && (result.length > 0))
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{
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if (!index) {
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index=0;
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}
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if (result[index].childNodes.length > 1) {
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return result.childNodes[1].nodeValue;
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}
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else if (result[index].childNodes.length == 1) {
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return result[index].firstChild.nodeValue;
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}
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} else {
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return "";
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}
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};
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/**
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* @param {XMLNode} node
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*
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* @returns The text value of the given node, without breaking in firefox or IE
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* @type String
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*/
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OpenLayers.Util.getXmlNodeValue = function(node) {
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var val = null;
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Try.these(
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function() {
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val = node.text;
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if (!val)
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val = node.textContent;
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},
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function() {
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val = node.textContent;
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});
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return val;
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};
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/**
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368 |
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* @param {Event} evt
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* @param {HTMLDivElement} div
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*
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* @return {boolean}
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*/
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OpenLayers.Util.mouseLeft = function (evt, div) {
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// start with the element to which the mouse has moved
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var target = (evt.relatedTarget) ? evt.relatedTarget : evt.toElement;
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// walk up the DOM tree.
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while (target != div && target != null) {
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target = target.parentNode;
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}
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// if the target we stop at isn't the div, then we've left the div.
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return (target != div);
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};
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383 |
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OpenLayers.Util.rad = function(x) {return x*Math.PI/180;};
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385 |
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OpenLayers.Util.distVincenty=function(p1, p2) {
|
386 |
|
|
var a = 6378137, b = 6356752.3142, f = 1/298.257223563;
|
387 |
|
|
var L = OpenLayers.Util.rad(p2.lon - p1.lon);
|
388 |
|
|
var U1 = Math.atan((1-f) * Math.tan(OpenLayers.Util.rad(p1.lat)));
|
389 |
|
|
var U2 = Math.atan((1-f) * Math.tan(OpenLayers.Util.rad(p2.lat)));
|
390 |
|
|
var sinU1 = Math.sin(U1), cosU1 = Math.cos(U1);
|
391 |
|
|
var sinU2 = Math.sin(U2), cosU2 = Math.cos(U2);
|
392 |
|
|
var lambda = L, lambdaP = 2*Math.PI;
|
393 |
|
|
var iterLimit = 20;
|
394 |
|
|
while (Math.abs(lambda-lambdaP) > 1e-12 && --iterLimit>0) {
|
395 |
|
|
var sinLambda = Math.sin(lambda), cosLambda = Math.cos(lambda);
|
396 |
|
|
var sinSigma = Math.sqrt((cosU2*sinLambda) * (cosU2*sinLambda) +
|
397 |
|
|
(cosU1*sinU2-sinU1*cosU2*cosLambda) * (cosU1*sinU2-sinU1*cosU2*cosLambda));
|
398 |
|
|
if (sinSigma==0) return 0; // co-incident points
|
399 |
|
|
var cosSigma = sinU1*sinU2 + cosU1*cosU2*cosLambda;
|
400 |
|
|
var sigma = Math.atan2(sinSigma, cosSigma);
|
401 |
|
|
var alpha = Math.asin(cosU1 * cosU2 * sinLambda / sinSigma);
|
402 |
|
|
var cosSqAlpha = Math.cos(alpha) * Math.cos(alpha);
|
403 |
|
|
var cos2SigmaM = cosSigma - 2*sinU1*sinU2/cosSqAlpha;
|
404 |
|
|
var C = f/16*cosSqAlpha*(4+f*(4-3*cosSqAlpha));
|
405 |
|
|
lambdaP = lambda;
|
406 |
|
|
lambda = L + (1-C) * f * Math.sin(alpha) *
|
407 |
|
|
(sigma + C*sinSigma*(cos2SigmaM+C*cosSigma*(-1+2*cos2SigmaM*cos2SigmaM)));
|
408 |
|
|
}
|
409 |
|
|
if (iterLimit==0) return NaN // formula failed to converge
|
410 |
|
|
var uSq = cosSqAlpha * (a*a - b*b) / (b*b);
|
411 |
|
|
var A = 1 + uSq/16384*(4096+uSq*(-768+uSq*(320-175*uSq)));
|
412 |
|
|
var B = uSq/1024 * (256+uSq*(-128+uSq*(74-47*uSq)));
|
413 |
|
|
var deltaSigma = B*sinSigma*(cos2SigmaM+B/4*(cosSigma*(-1+2*cos2SigmaM*cos2SigmaM)-
|
414 |
|
|
B/6*cos2SigmaM*(-3+4*sinSigma*sinSigma)*(-3+4*cos2SigmaM*cos2SigmaM)));
|
415 |
|
|
var s = b*A*(sigma-deltaSigma);
|
416 |
|
|
var d = s.toFixed(3)/1000; // round to 1mm precision
|
417 |
|
|
return d;
|
418 |
|
|
};
|
419 |
|
|
|
420 |
|
|
OpenLayers.Util.getArgs = function() {
|
421 |
|
|
var args = new Object();
|
422 |
|
|
var query = location.search.substring(1); // Get query string.
|
423 |
|
|
var pairs = query.split("&"); // Break at ampersand. //+pjl
|
424 |
|
|
|
425 |
|
|
for(var i = 0; i < pairs.length; i++) {
|
426 |
|
|
var pos = pairs[i].indexOf('='); // Look for "name=value".
|
427 |
|
|
if (pos == -1) continue; // If not found, skip.
|
428 |
|
|
var argname = pairs[i].substring(0,pos); // Extract the name.
|
429 |
|
|
var value = pairs[i].substring(pos+1); // Extract the value.
|
430 |
|
|
args[argname] = unescape(value); // Store as a property.
|
431 |
|
|
}
|
432 |
|
|
return args; // Return the object.
|
433 |
|
|
};
|
434 |
|
|
|
435 |
|
|
/**
|
436 |
|
|
* @param {String} prefix String to prefix random id. If null, default
|
437 |
|
|
* is "id_"
|
438 |
|
|
*
|
439 |
|
|
* @returns A unique id string, built on the passed in prefix
|
440 |
|
|
* @type String
|
441 |
|
|
*/
|
442 |
|
|
OpenLayers.Util.createUniqueID = function(prefix) {
|
443 |
|
|
if (prefix == null) {
|
444 |
|
|
prefix = "id_";
|
445 |
|
|
}
|
446 |
|
|
return prefix + Math.round(Math.random() * 10000);
|
447 |
|
|
};
|
448 |
|
|
|
449 |
|
|
/** Constant inches per unit
|
450 |
|
|
* -- borrowed from MapServer mapscale.c
|
451 |
|
|
*
|
452 |
|
|
* @type Object */
|
453 |
|
|
OpenLayers.INCHES_PER_UNIT = {
|
454 |
|
|
'inches': 1.0,
|
455 |
|
|
'ft': 12.0,
|
456 |
|
|
'mi': 63360.0,
|
457 |
|
|
'm': 39.3701,
|
458 |
|
|
'km': 39370.1,
|
459 |
|
|
'dd': 4374754
|
460 |
|
|
};
|
461 |
|
|
OpenLayers.INCHES_PER_UNIT["in"]= OpenLayers.INCHES_PER_UNIT.inches;
|
462 |
|
|
OpenLayers.INCHES_PER_UNIT["degrees"] = OpenLayers.INCHES_PER_UNIT.dd;
|
463 |
|
|
|
464 |
|
|
/** A sensible default
|
465 |
|
|
* @type int */
|
466 |
|
|
OpenLayers.DOTS_PER_INCH = 72;
|
467 |
|
|
|
468 |
|
|
/**
|
469 |
|
|
* @param {float} scale
|
470 |
|
|
*
|
471 |
|
|
* @returns A normalized scale value, in 1 / X format.
|
472 |
|
|
* This means that if a value less than one ( already 1/x) is passed
|
473 |
|
|
* in, it just returns scale directly. Otherwise, it returns
|
474 |
|
|
* 1 / scale
|
475 |
|
|
* @type float
|
476 |
|
|
*/
|
477 |
|
|
OpenLayers.Util.normalizeScale = function (scale) {
|
478 |
|
|
var normScale = (scale > 1.0) ? (1.0 / scale)
|
479 |
|
|
: scale;
|
480 |
|
|
return normScale;
|
481 |
|
|
};
|
482 |
|
|
|
483 |
|
|
/**
|
484 |
|
|
* @param {float} scale
|
485 |
|
|
* @param {String} units Index into OpenLayers.INCHES_PER_UNIT hashtable.
|
486 |
|
|
* Default is degrees
|
487 |
|
|
*
|
488 |
|
|
* @returns The corresponding resolution given passed-in scale and unit
|
489 |
|
|
* parameters.
|
490 |
|
|
* @type float
|
491 |
|
|
*/
|
492 |
|
|
OpenLayers.Util.getResolutionFromScale = function (scale, units) {
|
493 |
|
|
|
494 |
|
|
if (units == null) {
|
495 |
|
|
units = "degrees";
|
496 |
|
|
}
|
497 |
|
|
|
498 |
|
|
var normScale = OpenLayers.Util.normalizeScale(scale);
|
499 |
|
|
|
500 |
|
|
var resolution = 1 / (normScale * OpenLayers.INCHES_PER_UNIT[units]
|
501 |
|
|
* OpenLayers.DOTS_PER_INCH);
|
502 |
|
|
return resolution;
|
503 |
|
|
};
|