openseadragon/src/osmtilesource.js

154 lines
5.2 KiB
JavaScript

/*
* OpenSeadragon - OsmTileSource
*
* Copyright (C) 2009 CodePlex Foundation
* Copyright (C) 2010-2024 OpenSeadragon contributors
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of CodePlex Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Derived from the OSM tile source in Rainer Simon's seajax-utils project
* <http://github.com/rsimon/seajax-utils>. Rainer Simon has contributed
* the included code to the OpenSeadragon project under the New BSD license;
* see <https://github.com/openseadragon/openseadragon/issues/58>.
*/
(function( $ ){
/**
* @class OsmTileSource
* @classdesc A tilesource implementation for OpenStreetMap.<br><br>
*
* Note 1. Zoomlevels. Deep Zoom and OSM define zoom levels differently. In Deep
* Zoom, level 0 equals an image of 1x1 pixels. In OSM, level 0 equals an image of
* 256x256 levels (see http://gasi.ch/blog/inside-deep-zoom-2). I.e. there is a
* difference of log2(256)=8 levels.<br><br>
*
* Note 2. Image dimension. According to the OSM Wiki
* (http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Zoom_levels)
* the highest Mapnik zoom level has 256.144x256.144 tiles, with a 256x256
* pixel size. I.e. the Deep Zoom image dimension is 65.572.864x65.572.864
* pixels.
*
* @memberof OpenSeadragon
* @extends OpenSeadragon.TileSource
* @param {Number|Object} width - the pixel width of the image or the idiomatic
* options object which is used instead of positional arguments.
* @param {Number} height
* @param {Number} tileSize
* @param {Number} tileOverlap
* @param {String} tilesUrl
*/
$.OsmTileSource = function( width, height, tileSize, tileOverlap, tilesUrl ) {
var options;
if( $.isPlainObject( width ) ){
options = width;
}else{
options = {
width: arguments[0],
height: arguments[1],
tileSize: arguments[2],
tileOverlap: arguments[3],
tilesUrl: arguments[4]
};
}
//apply default setting for standard public OpenStreatMaps service
//but allow them to be specified so fliks can host there own instance
//or apply against other services supportting the same standard
if( !options.width || !options.height ){
options.width = 65572864;
options.height = 65572864;
}
if( !options.tileSize ){
options.tileSize = 256;
options.tileOverlap = 0;
}
if( !options.tilesUrl ){
options.tilesUrl = "http://tile.openstreetmap.org/";
}
options.minLevel = 8;
$.TileSource.apply( this, [ options ] );
};
$.extend( $.OsmTileSource.prototype, $.TileSource.prototype, /** @lends OpenSeadragon.OsmTileSource.prototype */{
/**
* Determine if the data and/or url imply the image service is supported by
* this tile source.
* @function
* @param {Object|Array} data
* @param {String} optional - url
*/
supports: function( data, url ){
return (
data.type &&
"openstreetmaps" === data.type
);
},
/**
*
* @function
* @param {Object} data - the raw configuration
* @param {String} url - the url the data was retrieved from if any.
* @param {String} postData - HTTP POST data in k=v&k2=v2... form or null
* @returns {Object} options - A dictionary of keyword arguments sufficient
* to configure this tile sources constructor.
*/
configure: function( data, url, postData ){
return data;
},
/**
* @function
* @param {Number} level
* @param {Number} x
* @param {Number} y
*/
getTileUrl: function( level, x, y ) {
return this.tilesUrl + (level - 8) + "/" + x + "/" + y + ".png";
},
/**
* Equality comparator
*/
equals: function(otherSource) {
return this.tilesUrl === otherSource.tilesUrl;
}
});
}( OpenSeadragon ));