5 * Called as the user scrolls/zooms around to aniplate hrefs of the
6 * view tab and various other links
8 function updatelinks(lon,lat,zoom,layers,minlon,minlat,maxlon,maxlat,objtype,objid) {
9 var decimals = Math.pow(10, Math.floor(zoom/3));
12 lat = Math.round(lat * decimals) / decimals;
13 lon = Math.round(lon * decimals) / decimals;
16 minlon = Math.round(minlon * decimals) / decimals;
17 minlat = Math.round(minlat * decimals) / decimals;
18 maxlon = Math.round(maxlon * decimals) / decimals;
19 maxlat = Math.round(maxlat * decimals) / decimals;
22 $(".geolink").each(function (index, link) {
23 var args = getArgs(link.href);
25 if ($(link).hasClass("llz")) {
29 } else if (minlon && $(link).hasClass("bbox")) {
30 args.bbox = minlon + "," + minlat + "," + maxlon + "," + maxlat;
33 if (layers && $(link).hasClass("layers")) {
37 if (objtype && $(link).hasClass("object")) {
38 args[objtype] = objid;
41 var classes = $(link).attr("class").split(" ");
43 $(classes).each(function (index, classname) {
44 if (match = classname.match(/^minzoom([0-9]+)$/)) {
45 var minzoom = match[1];
46 var name = link.id.replace(/anchor$/, "");
48 if (zoom >= minzoom) {
50 $(link).attr("title", i18n("javascripts.site." + name + "_tooltip"));
51 $(link).removeClass("disabled");
53 $(link).click(function () { alert(i18n("javascripts.site." + name + "_zoom_alert")); return false; });
54 $(link).attr("title", i18n("javascripts.site." + name + "_disabled_tooltip"));
55 $(link).addClass("disabled");
60 link.href = setArgs(link.href, args);
63 $("#shortlinkanchor").each(function () {
64 var args = getArgs(this.href);
65 var code = makeShortCode(lat, lon, zoom);
66 var prefix = shortlinkPrefix();
68 // Add ?{node,way,relation}=id to the arguments
69 if (objtype && objid) {
70 args[objtype] = objid;
73 // This is a hack to omit the default mapnik layer from the shortlink.
74 if (layers && layers != "M") {
81 // Here we're assuming that all parameters but ?layers= and
82 // ?{node,way,relation}= can be safely omitted from the shortlink
83 // which encodes lat/lon/zoom. If new URL parameters are added to
84 // the main slippy map this needs to be changed.
85 if (args.layers || args[objtype]) {
86 this.href = setArgs(prefix + "/go/" + code, args);
88 this.href = prefix + "/go/" + code;
94 * Get the URL prefix to use for a short link
96 function shortlinkPrefix() {
97 if (window.location.hostname.match(/^www\.openstreetmap\.org/i)) {
98 return "http://osm.org";
105 * Called to get the arguments from a URL as a hash.
107 function getArgs(url) {
109 var querystart = url.indexOf("?");
111 if (querystart >= 0) {
112 var querystring = url.substring(querystart + 1);
113 var queryitems = querystring.split("&");
115 for (var i = 0; i < queryitems.length; i++) {
116 if (match = queryitems[i].match(/^(.*)=(.*)$/)) {
117 args[unescape(match[1])] = unescape(match[2]);
119 args[unescape(queryitems[i])] = null;
128 * Called to set the arguments on a URL from the given hash.
130 function setArgs(url, args) {
134 if (args[arg] == null) {
135 queryitems.push(escape(arg));
137 queryitems.push(escape(arg) + "=" + escape(args[arg]));
141 return url.replace(/\?.*$/, "") + "?" + queryitems.join("&");
145 * Called to get a CSS property for an element.
147 function getStyle(el, property) {
150 if (el.currentStyle) {
151 style = el.currentStyle[property];
152 } else if( window.getComputedStyle ) {
153 style = document.defaultView.getComputedStyle(el,null).getPropertyValue(property);
155 style = el.style[property];
162 * Called to interpolate JavaScript variables in strings using a
163 * similar syntax to rails I18n string interpolation - the only
164 * difference is that [[foo]] is the placeholder syntax instead
165 * of {{foo}} which allows the same string to be processed by both
166 * rails and then later by javascript.
168 function i18n(string, keys) {
169 string = i18n_strings[string] || string;
171 for (var key in keys) {
172 var re_key = '\\[\\[' + key + '\\]\\]';
173 var re = new RegExp(re_key, "g");
175 string = string.replace(re, keys[key]);
182 * Called to interlace the bits in x and y, making a Morton code.
184 function interlace(x, y) {
185 x = (x | (x << 8)) & 0x00ff00ff;
186 x = (x | (x << 4)) & 0x0f0f0f0f;
187 x = (x | (x << 2)) & 0x33333333;
188 x = (x | (x << 1)) & 0x55555555;
190 y = (y | (y << 8)) & 0x00ff00ff;
191 y = (y | (y << 4)) & 0x0f0f0f0f;
192 y = (y | (y << 2)) & 0x33333333;
193 y = (y | (y << 1)) & 0x55555555;
199 * Called to create a short code for the short link.
201 function makeShortCode(lat, lon, zoom) {
202 char_array = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_~";
203 var x = Math.round((lon + 180.0) * ((1 << 30) / 90.0));
204 var y = Math.round((lat + 90.0) * ((1 << 30) / 45.0));
205 // JavaScript only has to keep 32 bits of bitwise operators, so this has to be
206 // done in two parts. each of the parts c1/c2 has 30 bits of the total in it
207 // and drops the last 4 bits of the full 64 bit Morton code.
209 var c1 = interlace(x >>> 17, y >>> 17), c2 = interlace((x >>> 2) & 0x7fff, (y >>> 2) & 0x7fff);
210 for (var i = 0; i < Math.ceil((zoom + 8) / 3.0) && i < 5; ++i) {
211 digit = (c1 >> (24 - 6 * i)) & 0x3f;
212 str += char_array.charAt(digit);
214 for (var i = 5; i < Math.ceil((zoom + 8) / 3.0); ++i) {
215 digit = (c2 >> (24 - 6 * (i - 5))) & 0x3f;
216 str += char_array.charAt(digit);
218 for (var i = 0; i < ((zoom + 8) % 3); ++i) {