Add a javascript file to provide OSM layers for OpenStreetMap.

This commit is contained in:
Tom Hughes 2007-11-28 18:59:05 +00:00
parent 2ba147e7fa
commit 29645d2d29

View file

@ -0,0 +1,144 @@
/**
* Namespace: Util.OSM
*/
OpenLayers.Util.OSM = {};
/**
* Constant: MISSING_TILE_URL
* {String} URL of image to display for missing tiles
*/
OpenLayers.Util.OSM.MISSING_TILE_URL = "http://openstreetmap.org/openlayers/img/404.png";
/**
* Property: originalOnImageLoadError
* {Function} Original onImageLoadError function.
*/
OpenLayers.Util.OSM.originalOnImageLoadError = OpenLayers.Util.onImageLoadError;
/**
* Function: onImageLoadError
*/
OpenLayers.Util.onImageLoadError = function() {
if (this.src.match(/^http:\/\/[abc]\.[a-z]+\.openstreetmap\.org/)) {
this.src = OpenLayers.Util.OSM.MISSING_TILE_URL;
} else {
OpenLayers.Util.OSM.originalOnImageLoadError;
}
};
/**
* @requires OpenLayers/Layer/TMS.js
*
* Class: OpenLayers.Layer.OSM
*
* Inherits from:
* - <OpenLayers.Layer.TMS>
*/
OpenLayers.Layer.OSM = OpenLayers.Class(OpenLayers.Layer.TMS, {
/**
* Constructor: OpenLayers.Layer.OSM
*
* Parameters:
* name - {String}
* url - {String}
* options - {Object} Hashtable of extra options to tag onto the layer
*/
initialize: function(name, url, options) {
options = OpenLayers.Util.extend(options, { attribution: "Powered by <a href='http://openstreetmap.org/'>OpenStreetMap</a>" });
OpenLayers.Layer.TMS.prototype.initialize.apply(this, arguments);
},
/**
* 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) {
var res = this.map.getResolution();
var x = Math.round((bounds.left - this.maxExtent.left) / (res * this.tileSize.w));
var y = Math.round((this.maxExtent.top - bounds.top) / (res * this.tileSize.h));
var z = this.map.getZoom();
var limit = Math.pow(2, z);
if (y < 0 || y >= limit)
{
return OpenLayers.Util.OSM.MISSING_TILE_URL;
}
else
{
x = ((x % limit) + limit) % limit;
var url = this.url;
var path = z + "/" + x + "/" + y + ".png";
if (url instanceof Array)
{
url = this.selectUrl(path, url);
}
return url + path;
}
},
CLASS_NAME: "OpenLayers.Layer.OSM"
});
/**
* Class: OpenLayers.Layer.OSM.Mapnik
*
* Inherits from:
* - <OpenLayers.Layer.OSM>
*/
OpenLayers.Layer.OSM.Mapnik = OpenLayers.Class(OpenLayers.Layer.OSM, {
/**
* Constructor: OpenLayers.Layer.OSM.Mapnik
*
* Parameters:
* name - {String}
* options - {Object} Hashtable of extra options to tag onto the layer
*/
initialize: function(name, options) {
var url = [
"http://a.tile.openstreetmap.org/",
"http://b.tile.openstreetmap.org/",
"http://c.tile.openstreetmap.org/"
];
var newArguments = [name, url, options];
OpenLayers.Layer.OSM.prototype.initialize.apply(this, newArguments);
},
CLASS_NAME: "OpenLayers.Layer.OSM.Mapnik"
});
/**
* Class: OpenLayers.Layer.OSM.Osmarender
*
* Inherits from:
* - <OpenLayers.Layer.OSM>
*/
OpenLayers.Layer.OSM.Osmarender = OpenLayers.Class(OpenLayers.Layer.OSM, {
/**
* Constructor: OpenLayers.Layer.OSM.Osmarender
*
* Parameters:
* name - {String}
* options - {Object} Hashtable of extra options to tag onto the layer
*/
initialize: function(name, options) {
var url = [
"http://a.tah.openstreetmap.org/Tiles/tile.php/",
"http://b.tah.openstreetmap.org/Tiles/tile.php/",
"http://c.tah.openstreetmap.org/Tiles/tile.php/"
];
var newArguments = [name, url, options];
OpenLayers.Layer.OSM.prototype.initialize.apply(this, newArguments);
},
CLASS_NAME: "OpenLayers.Layer.OSM.Osmarender"
});