cesium
Version:
CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.
385 lines (349 loc) • 14.4 kB
JavaScript
import Credit from '../Core/Credit.js';
import defaultValue from '../Core/defaultValue.js';
import defined from '../Core/defined.js';
import DeveloperError from '../Core/DeveloperError.js';
import Event from '../Core/Event.js';
import GeographicTilingScheme from '../Core/GeographicTilingScheme.js';
import Rectangle from '../Core/Rectangle.js';
import Resource from '../Core/Resource.js';
import RuntimeError from '../Core/RuntimeError.js';
import TileProviderError from '../Core/TileProviderError.js';
import when from '../ThirdParty/when.js';
import ImageryProvider from './ImageryProvider.js';
/**
* Provides a single, top-level imagery tile. The single image is assumed to use a
* {@link GeographicTilingScheme}.
*
* @alias SingleTileImageryProvider
* @constructor
*
* @param {Object} options Object with the following properties:
* @param {Resource|String} options.url The url for the tile.
* @param {Rectangle} [options.rectangle=Rectangle.MAX_VALUE] The rectangle, in radians, covered by the image.
* @param {Credit|String} [options.credit] A credit for the data source, which is displayed on the canvas.
* @param {Ellipsoid} [options.ellipsoid] The ellipsoid. If not specified, the WGS84 ellipsoid is used.
*
* @see ArcGisMapServerImageryProvider
* @see BingMapsImageryProvider
* @see GoogleEarthEnterpriseMapsProvider
* @see OpenStreetMapImageryProvider
* @see TileMapServiceImageryProvider
* @see WebMapServiceImageryProvider
* @see WebMapTileServiceImageryProvider
* @see UrlTemplateImageryProvider
*/
function SingleTileImageryProvider(options) {
options = defaultValue(options, defaultValue.EMPTY_OBJECT);
//>>includeStart('debug', pragmas.debug);
if (!defined(options.url)) {
throw new DeveloperError('options.url is required.');
}
//>>includeEnd('debug');
var resource = Resource.createIfNeeded(options.url);
var rectangle = defaultValue(options.rectangle, Rectangle.MAX_VALUE);
var tilingScheme = new GeographicTilingScheme({
rectangle : rectangle,
numberOfLevelZeroTilesX : 1,
numberOfLevelZeroTilesY : 1,
ellipsoid : options.ellipsoid
});
this._tilingScheme = tilingScheme;
this._resource = resource;
this._image = undefined;
this._texture = undefined;
this._tileWidth = 0;
this._tileHeight = 0;
this._errorEvent = new Event();
this._ready = false;
this._readyPromise = when.defer();
var credit = options.credit;
if (typeof credit === 'string') {
credit = new Credit(credit);
}
this._credit = credit;
var that = this;
var error;
function success(image) {
that._image = image;
that._tileWidth = image.width;
that._tileHeight = image.height;
that._ready = true;
that._readyPromise.resolve(true);
TileProviderError.handleSuccess(that._errorEvent);
}
function failure(e) {
var message = 'Failed to load image ' + resource.url + '.';
error = TileProviderError.handleError(
error,
that,
that._errorEvent,
message,
0, 0, 0,
doRequest,
e);
that._readyPromise.reject(new RuntimeError(message));
}
function doRequest() {
ImageryProvider
.loadImage(null, resource)
.then(success)
.otherwise(failure);
}
doRequest();
}
Object.defineProperties(SingleTileImageryProvider.prototype, {
/**
* Gets the URL of the single, top-level imagery tile.
* @memberof SingleTileImageryProvider.prototype
* @type {String}
* @readonly
*/
url : {
get : function() {
return this._resource.url;
}
},
/**
* Gets the proxy used by this provider.
* @memberof SingleTileImageryProvider.prototype
* @type {Proxy}
* @readonly
*/
proxy : {
get : function() {
return this._resource.proxy;
}
},
/**
* Gets the width of each tile, in pixels. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Number}
* @readonly
*/
tileWidth : {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('tileWidth must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return this._tileWidth;
}
},
/**
* Gets the height of each tile, in pixels. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Number}
* @readonly
*/
tileHeight: {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('tileHeight must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return this._tileHeight;
}
},
/**
* Gets the maximum level-of-detail that can be requested. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Number}
* @readonly
*/
maximumLevel : {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('maximumLevel must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return 0;
}
},
/**
* Gets the minimum level-of-detail that can be requested. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Number}
* @readonly
*/
minimumLevel : {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('minimumLevel must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return 0;
}
},
/**
* Gets the tiling scheme used by this provider. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {TilingScheme}
* @readonly
*/
tilingScheme : {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('tilingScheme must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return this._tilingScheme;
}
},
/**
* Gets the rectangle, in radians, of the imagery provided by this instance. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Rectangle}
* @readonly
*/
rectangle : {
get : function() {
return this._tilingScheme.rectangle;
}
},
/**
* Gets the tile discard policy. If not undefined, the discard policy is responsible
* for filtering out "missing" tiles via its shouldDiscardImage function. If this function
* returns undefined, no tiles are filtered. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {TileDiscardPolicy}
* @readonly
*/
tileDiscardPolicy : {
get : function() {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('tileDiscardPolicy must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return undefined;
}
},
/**
* Gets an event that is raised when the imagery provider encounters an asynchronous error. By subscribing
* to the event, you will be notified of the error and can potentially recover from it. Event listeners
* are passed an instance of {@link TileProviderError}.
* @memberof SingleTileImageryProvider.prototype
* @type {Event}
* @readonly
*/
errorEvent : {
get : function() {
return this._errorEvent;
}
},
/**
* Gets a value indicating whether or not the provider is ready for use.
* @memberof SingleTileImageryProvider.prototype
* @type {Boolean}
* @readonly
*/
ready : {
get : function() {
return this._ready;
}
},
/**
* Gets a promise that resolves to true when the provider is ready for use.
* @memberof SingleTileImageryProvider.prototype
* @type {Promise.<Boolean>}
* @readonly
*/
readyPromise : {
get : function() {
return this._readyPromise.promise;
}
},
/**
* Gets the credit to display when this imagery provider is active. Typically this is used to credit
* the source of the imagery. This function should not be called before {@link SingleTileImageryProvider#ready} returns true.
* @memberof SingleTileImageryProvider.prototype
* @type {Credit}
* @readonly
*/
credit : {
get : function() {
return this._credit;
}
},
/**
* Gets a value indicating whether or not the images provided by this imagery provider
* include an alpha channel. If this property is false, an alpha channel, if present, will
* be ignored. If this property is true, any images without an alpha channel will be treated
* as if their alpha is 1.0 everywhere. When this property is false, memory usage
* and texture upload time are reduced.
* @memberof SingleTileImageryProvider.prototype
* @type {Boolean}
* @readonly
*/
hasAlphaChannel : {
get : function() {
return true;
}
}
});
/**
* Gets the credits to be displayed when a given tile is displayed.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level;
* @returns {Credit[]} The credits to be displayed when the tile is displayed.
*
* @exception {DeveloperError} <code>getTileCredits</code> must not be called before the imagery provider is ready.
*/
SingleTileImageryProvider.prototype.getTileCredits = function(x, y, level) {
return undefined;
};
/**
* Requests the image for a given tile. This function should
* not be called before {@link SingleTileImageryProvider#ready} returns true.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level.
* @param {Request} [request] The request object. Intended for internal use only.
* @returns {Promise.<Image|Canvas>|undefined} A promise for the image that will resolve when the image is available, or
* undefined if there are too many active requests to the server, and the request
* should be retried later. The resolved image may be either an
* Image or a Canvas DOM object.
*
* @exception {DeveloperError} <code>requestImage</code> must not be called before the imagery provider is ready.
*/
SingleTileImageryProvider.prototype.requestImage = function(x, y, level, request) {
//>>includeStart('debug', pragmas.debug);
if (!this._ready) {
throw new DeveloperError('requestImage must not be called before the imagery provider is ready.');
}
//>>includeEnd('debug');
return this._image;
};
/**
* Picking features is not currently supported by this imagery provider, so this function simply returns
* undefined.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level.
* @param {Number} longitude The longitude at which to pick features.
* @param {Number} latitude The latitude at which to pick features.
* @return {Promise.<ImageryLayerFeatureInfo[]>|undefined} A promise for the picked features that will resolve when the asynchronous
* picking completes. The resolved value is an array of {@link ImageryLayerFeatureInfo}
* instances. The array may be empty if no features are found at the given location.
* It may also be undefined if picking is not supported.
*/
SingleTileImageryProvider.prototype.pickFeatures = function(x, y, level, longitude, latitude) {
return undefined;
};
export default SingleTileImageryProvider;