Files
openlayers/src/ol/source/tilejsonsource.js
2013-08-30 16:50:36 +02:00

136 lines
3.0 KiB
JavaScript

// FIXME add some error checking
// FIXME check order of async callbacks
/**
* @see http://mapbox.com/developers/api/
*/
goog.provide('ol.source.TileJSON');
goog.provide('ol.tilejson');
goog.require('goog.asserts');
goog.require('goog.net.jsloader');
goog.require('ol.Attribution');
goog.require('ol.TileRange');
goog.require('ol.TileUrlFunction');
goog.require('ol.extent');
goog.require('ol.proj');
goog.require('ol.source.ImageTileSource');
goog.require('ol.tilegrid.XYZ');
/**
* @private
* @type {Array.<TileJSON>}
*/
ol.tilejson.grids_ = [];
/**
* @param {TileJSON} tileJSON Tile JSON.
*/
var grid = function(tileJSON) {
ol.tilejson.grids_.push(tileJSON);
};
goog.exportSymbol('grid', grid);
/**
* @constructor
* @extends {ol.source.ImageTileSource}
* @param {ol.source.TileJSONOptions} options TileJSON options.
*/
ol.source.TileJSON = function(options) {
goog.base(this, {
crossOrigin: options.crossOrigin,
projection: ol.proj.get('EPSG:3857')
});
/**
* @private
* @type {boolean}
*/
this.ready_ = false;
/**
* @private
* @type {!goog.async.Deferred}
*/
this.deferred_ = goog.net.jsloader.load(options.url, {cleanupWhenDone: true});
this.deferred_.addCallback(this.handleTileJSONResponse, this);
};
goog.inherits(ol.source.TileJSON, ol.source.ImageTileSource);
/**
* @protected
*/
ol.source.TileJSON.prototype.handleTileJSONResponse = function() {
var tileJSON = ol.tilejson.grids_.pop();
var epsg4326Projection = ol.proj.get('EPSG:4326');
var extent;
if (goog.isDef(tileJSON.bounds)) {
var bounds = tileJSON.bounds;
var epsg4326Extent = [bounds[0], bounds[2], bounds[1], bounds[3]];
var transform = ol.proj.getTransformFromProjections(
epsg4326Projection, this.getProjection());
extent = ol.extent.transform(epsg4326Extent, transform);
this.setExtent(extent);
}
if (goog.isDef(tileJSON.scheme)) {
goog.asserts.assert(tileJSON.scheme == 'xyz');
}
var minZoom = tileJSON.minzoom || 0;
var maxZoom = tileJSON.maxzoom || 22;
var tileGrid = new ol.tilegrid.XYZ({
maxZoom: maxZoom,
minZoom: minZoom
});
this.tileGrid = tileGrid;
this.tileUrlFunction = ol.TileUrlFunction.withTileCoordTransform(
tileGrid.createTileCoordTransform({
extent: extent
}),
ol.TileUrlFunction.createFromTemplates(tileJSON.tiles));
if (goog.isDef(tileJSON.attribution)) {
var attributionExtent = goog.isDef(extent) ?
extent : epsg4326Projection.getExtent();
/** @type {Object.<string, Array.<ol.TileRange>>} */
var tileRanges = {};
var z, zKey;
for (z = minZoom; z <= maxZoom; ++z) {
zKey = z.toString();
tileRanges[zKey] =
[tileGrid.getTileRangeForExtentAndZ(attributionExtent, z)];
}
this.setAttributions([
new ol.Attribution({
html: tileJSON.attribution,
tileRanges: tileRanges
})
]);
}
this.ready_ = true;
this.dispatchLoadEvent();
};
/**
* @inheritDoc
*/
ol.source.TileJSON.prototype.isReady = function() {
return this.ready_;
};