SingleTileImageryProvider.js 22 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674
  1. import Check from "../Core/Check.js";
  2. import Credit from "../Core/Credit.js";
  3. import defaultValue from "../Core/defaultValue.js";
  4. import defined from "../Core/defined.js";
  5. import deprecationWarning from "../Core/deprecationWarning.js";
  6. import Event from "../Core/Event.js";
  7. import GeographicTilingScheme from "../Core/GeographicTilingScheme.js";
  8. import Rectangle from "../Core/Rectangle.js";
  9. import Resource from "../Core/Resource.js";
  10. import RuntimeError from "../Core/RuntimeError.js";
  11. import TileProviderError from "../Core/TileProviderError.js";
  12. import ImageryProvider from "./ImageryProvider.js";
  13. /**
  14. * @typedef {object} SingleTileImageryProvider.ConstructorOptions
  15. *
  16. * Initialization options for the SingleTileImageryProvider constructor
  17. *
  18. * @property {Resource|string} url The url for the tile.
  19. * @property {number} [tileWidth] The width of the tile, in pixels.
  20. * @property {number} [tileHeight] The height of the tile, in pixels.
  21. * @property {Rectangle} [rectangle=Rectangle.MAX_VALUE] The rectangle, in radians, covered by the image.
  22. * @property {Credit|string} [credit] A credit for the data source, which is displayed on the canvas.
  23. * @property {Ellipsoid} [ellipsoid] The ellipsoid. If not specified, the WGS84 ellipsoid is used.
  24. */
  25. /**
  26. * Provides a single, top-level imagery tile. The single image is assumed to use a
  27. * {@link GeographicTilingScheme}.
  28. *
  29. * @alias SingleTileImageryProvider
  30. * @constructor
  31. *
  32. * @param {SingleTileImageryProvider.ConstructorOptions} options Object describing initialization options
  33. *
  34. * @see ArcGisMapServerImageryProvider
  35. * @see BingMapsImageryProvider
  36. * @see GoogleEarthEnterpriseMapsProvider
  37. * @see OpenStreetMapImageryProvider
  38. * @see TileMapServiceImageryProvider
  39. * @see WebMapServiceImageryProvider
  40. * @see WebMapTileServiceImageryProvider
  41. * @see UrlTemplateImageryProvider
  42. */
  43. function SingleTileImageryProvider(options) {
  44. options = defaultValue(options, defaultValue.EMPTY_OBJECT);
  45. this._defaultAlpha = undefined;
  46. this._defaultNightAlpha = undefined;
  47. this._defaultDayAlpha = undefined;
  48. this._defaultBrightness = undefined;
  49. this._defaultContrast = undefined;
  50. this._defaultHue = undefined;
  51. this._defaultSaturation = undefined;
  52. this._defaultGamma = undefined;
  53. this._defaultMinificationFilter = undefined;
  54. this._defaultMagnificationFilter = undefined;
  55. const rectangle = defaultValue(options.rectangle, Rectangle.MAX_VALUE);
  56. const tilingScheme = new GeographicTilingScheme({
  57. rectangle: rectangle,
  58. numberOfLevelZeroTilesX: 1,
  59. numberOfLevelZeroTilesY: 1,
  60. ellipsoid: options.ellipsoid,
  61. });
  62. this._tilingScheme = tilingScheme;
  63. this._image = undefined;
  64. this._texture = undefined;
  65. this._hasError = false;
  66. this._errorEvent = new Event();
  67. this._ready = false;
  68. let credit = options.credit;
  69. if (typeof credit === "string") {
  70. credit = new Credit(credit);
  71. }
  72. this._credit = credit;
  73. //>>includeStart('debug', pragmas.debug);
  74. Check.defined("options.url", options.url);
  75. //>>includeEnd('debug');
  76. const resource = Resource.createIfNeeded(options.url);
  77. this._resource = resource;
  78. // After ready promise and the deprecation warning for these properties are removed,
  79. // the if check is not needed, and this can become a top-level block
  80. if (defined(options.tileWidth) || defined(options.tileHeight)) {
  81. //>>includeStart('debug', pragmas.debug);
  82. Check.typeOf.number("options.tileWidth", options.tileWidth);
  83. Check.typeOf.number("options.tileHeight", options.tileHeight);
  84. //>>includeEnd('debug');
  85. this._tileWidth = options.tileWidth;
  86. this._tileHeight = options.tileHeight;
  87. this._ready = true;
  88. this._readyPromise = Promise.resolve(true);
  89. return;
  90. }
  91. deprecationWarning(
  92. "SingleTileImageryProvider options",
  93. "options.tileHeight and options.tileWidth became required in CesiumJS 1.104. Omitting these properties will result in an error in 1.107. Provide options.tileHeight and options.tileWidth, or use SingleTileImageryProvider.fromUrl instead."
  94. );
  95. this._tileWidth = 0;
  96. this._tileHeight = 0;
  97. this._readyPromise = doRequest(resource, this).then((image) => {
  98. TileProviderError.reportSuccess(this._errorEvent);
  99. this._image = image;
  100. this._tileWidth = image.width;
  101. this._tileHeight = image.height;
  102. this._ready = true;
  103. return true;
  104. });
  105. }
  106. Object.defineProperties(SingleTileImageryProvider.prototype, {
  107. /**
  108. * Gets the URL of the single, top-level imagery tile.
  109. * @memberof SingleTileImageryProvider.prototype
  110. * @type {string}
  111. * @readonly
  112. */
  113. url: {
  114. get: function () {
  115. return this._resource.url;
  116. },
  117. },
  118. /**
  119. * Gets the proxy used by this provider.
  120. * @memberof SingleTileImageryProvider.prototype
  121. * @type {Proxy}
  122. * @readonly
  123. */
  124. proxy: {
  125. get: function () {
  126. return this._resource.proxy;
  127. },
  128. },
  129. /**
  130. * Gets the width of each tile, in pixels.
  131. * @memberof SingleTileImageryProvider.prototype
  132. * @type {number}
  133. * @readonly
  134. */
  135. tileWidth: {
  136. get: function () {
  137. return this._tileWidth;
  138. },
  139. },
  140. /**
  141. * Gets the height of each tile, in pixels.
  142. * @memberof SingleTileImageryProvider.prototype
  143. * @type {number}
  144. * @readonly
  145. */
  146. tileHeight: {
  147. get: function () {
  148. return this._tileHeight;
  149. },
  150. },
  151. /**
  152. * Gets the maximum level-of-detail that can be requested.
  153. * @memberof SingleTileImageryProvider.prototype
  154. * @type {number|undefined}
  155. * @readonly
  156. */
  157. maximumLevel: {
  158. get: function () {
  159. return 0;
  160. },
  161. },
  162. /**
  163. * Gets the minimum level-of-detail that can be requested.
  164. * @memberof SingleTileImageryProvider.prototype
  165. * @type {number}
  166. * @readonly
  167. */
  168. minimumLevel: {
  169. get: function () {
  170. return 0;
  171. },
  172. },
  173. /**
  174. * Gets the tiling scheme used by this provider.
  175. * @memberof SingleTileImageryProvider.prototype
  176. * @type {TilingScheme}
  177. * @readonly
  178. */
  179. tilingScheme: {
  180. get: function () {
  181. return this._tilingScheme;
  182. },
  183. },
  184. /**
  185. * Gets the rectangle, in radians, of the imagery provided by this instance.
  186. * @memberof SingleTileImageryProvider.prototype
  187. * @type {Rectangle}
  188. * @readonly
  189. */
  190. rectangle: {
  191. get: function () {
  192. return this._tilingScheme.rectangle;
  193. },
  194. },
  195. /**
  196. * Gets the tile discard policy. If not undefined, the discard policy is responsible
  197. * for filtering out "missing" tiles via its shouldDiscardImage function. If this function
  198. * returns undefined, no tiles are filtered.
  199. * @memberof SingleTileImageryProvider.prototype
  200. * @type {TileDiscardPolicy}
  201. * @readonly
  202. */
  203. tileDiscardPolicy: {
  204. get: function () {
  205. return undefined;
  206. },
  207. },
  208. /**
  209. * Gets an event that is raised when the imagery provider encounters an asynchronous error. By subscribing
  210. * to the event, you will be notified of the error and can potentially recover from it. Event listeners
  211. * are passed an instance of {@link TileProviderError}.
  212. * @memberof SingleTileImageryProvider.prototype
  213. * @type {Event}
  214. * @readonly
  215. */
  216. errorEvent: {
  217. get: function () {
  218. return this._errorEvent;
  219. },
  220. },
  221. /**
  222. * Gets a value indicating whether or not the provider is ready for use.
  223. * @memberof SingleTileImageryProvider.prototype
  224. * @type {boolean}
  225. * @readonly
  226. * @deprecated
  227. */
  228. ready: {
  229. get: function () {
  230. deprecationWarning(
  231. "SingleTileImageryProvider.ready",
  232. "SingleTileImageryProvider.ready was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use SingleTileImageryProvider.fromUrl instead."
  233. );
  234. return this._ready;
  235. },
  236. },
  237. /**
  238. * Gets a promise that resolves to true when the provider is ready for use.
  239. * @memberof SingleTileImageryProvider.prototype
  240. * @type {Promise<boolean>}
  241. * @readonly
  242. * @deprecated
  243. */
  244. readyPromise: {
  245. get: function () {
  246. deprecationWarning(
  247. "SingleTileImageryProvider.readyPromise",
  248. "SingleTileImageryProvider.readyPromise was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use SingleTileImageryProvider.fromUrl instead."
  249. );
  250. return this._readyPromise;
  251. },
  252. },
  253. /**
  254. * Gets the credit to display when this imagery provider is active. Typically this is used to credit
  255. * the source of the imagery.
  256. * @memberof SingleTileImageryProvider.prototype
  257. * @type {Credit}
  258. * @readonly
  259. */
  260. credit: {
  261. get: function () {
  262. return this._credit;
  263. },
  264. },
  265. /**
  266. * Gets a value indicating whether or not the images provided by this imagery provider
  267. * include an alpha channel. If this property is false, an alpha channel, if present, will
  268. * be ignored. If this property is true, any images without an alpha channel will be treated
  269. * as if their alpha is 1.0 everywhere. When this property is false, memory usage
  270. * and texture upload time are reduced.
  271. * @memberof SingleTileImageryProvider.prototype
  272. * @type {boolean}
  273. * @readonly
  274. */
  275. hasAlphaChannel: {
  276. get: function () {
  277. return true;
  278. },
  279. },
  280. /**
  281. * The default alpha blending value of this provider, with 0.0 representing fully transparent and
  282. * 1.0 representing fully opaque.
  283. * @memberof SingleTileImageryProvider.prototype
  284. * @type {Number|undefined}
  285. * @deprecated
  286. */
  287. defaultAlpha: {
  288. get: function () {
  289. deprecationWarning(
  290. "SingleTileImageryProvider.defaultAlpha",
  291. "SingleTileImageryProvider.defaultAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.alpha instead."
  292. );
  293. return this._defaultAlpha;
  294. },
  295. set: function (value) {
  296. deprecationWarning(
  297. "SingleTileImageryProvider.defaultAlpha",
  298. "SingleTileImageryProvider.defaultAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.alpha instead."
  299. );
  300. this._defaultAlpha = value;
  301. },
  302. },
  303. /**
  304. * The default alpha blending value on the night side of the globe of this provider, with 0.0 representing fully transparent and
  305. * 1.0 representing fully opaque.
  306. * @memberof SingleTileImageryProvider.prototype
  307. * @type {Number|undefined}
  308. * @deprecated
  309. */
  310. defaultNightAlpha: {
  311. get: function () {
  312. deprecationWarning(
  313. "SingleTileImageryProvider.defaultNightAlpha",
  314. "SingleTileImageryProvider.defaultNightAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.nightAlpha instead."
  315. );
  316. return this._defaultNightAlpha;
  317. },
  318. set: function (value) {
  319. deprecationWarning(
  320. "SingleTileImageryProvider.defaultNightAlpha",
  321. "SingleTileImageryProvider.defaultNightAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.nightAlpha instead."
  322. );
  323. this._defaultNightAlpha = value;
  324. },
  325. },
  326. /**
  327. * The default alpha blending value on the day side of the globe of this provider, with 0.0 representing fully transparent and
  328. * 1.0 representing fully opaque.
  329. * @memberof SingleTileImageryProvider.prototype
  330. * @type {Number|undefined}
  331. * @deprecated
  332. */
  333. defaultDayAlpha: {
  334. get: function () {
  335. deprecationWarning(
  336. "SingleTileImageryProvider.defaultDayAlpha",
  337. "SingleTileImageryProvider.defaultDayAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.dayAlpha instead."
  338. );
  339. return this._defaultDayAlpha;
  340. },
  341. set: function (value) {
  342. deprecationWarning(
  343. "SingleTileImageryProvider.defaultDayAlpha",
  344. "SingleTileImageryProvider.defaultDayAlpha was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.dayAlpha instead."
  345. );
  346. this._defaultDayAlpha = value;
  347. },
  348. },
  349. /**
  350. * The default brightness of this provider. 1.0 uses the unmodified imagery color. Less than 1.0
  351. * makes the imagery darker while greater than 1.0 makes it brighter.
  352. * @memberof SingleTileImageryProvider.prototype
  353. * @type {Number|undefined}
  354. * @deprecated
  355. */
  356. defaultBrightness: {
  357. get: function () {
  358. deprecationWarning(
  359. "SingleTileImageryProvider.defaultBrightness",
  360. "SingleTileImageryProvider.defaultBrightness was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.brightness instead."
  361. );
  362. return this._defaultBrightness;
  363. },
  364. set: function (value) {
  365. deprecationWarning(
  366. "SingleTileImageryProvider.defaultBrightness",
  367. "SingleTileImageryProvider.defaultBrightness was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.brightness instead."
  368. );
  369. this._defaultBrightness = value;
  370. },
  371. },
  372. /**
  373. * The default contrast of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 reduces
  374. * the contrast while greater than 1.0 increases it.
  375. * @memberof SingleTileImageryProvider.prototype
  376. * @type {Number|undefined}
  377. * @deprecated
  378. */
  379. defaultContrast: {
  380. get: function () {
  381. deprecationWarning(
  382. "SingleTileImageryProvider.defaultContrast",
  383. "SingleTileImageryProvider.defaultContrast was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.contrast instead."
  384. );
  385. return this._defaultContrast;
  386. },
  387. set: function (value) {
  388. deprecationWarning(
  389. "SingleTileImageryProvider.defaultContrast",
  390. "SingleTileImageryProvider.defaultContrast was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.contrast instead."
  391. );
  392. this._defaultContrast = value;
  393. },
  394. },
  395. /**
  396. * The default hue of this provider in radians. 0.0 uses the unmodified imagery color.
  397. * @memberof SingleTileImageryProvider.prototype
  398. * @type {Number|undefined}
  399. * @deprecated
  400. */
  401. defaultHue: {
  402. get: function () {
  403. deprecationWarning(
  404. "SingleTileImageryProvider.defaultHue",
  405. "SingleTileImageryProvider.defaultHue was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.hue instead."
  406. );
  407. return this._defaultHue;
  408. },
  409. set: function (value) {
  410. deprecationWarning(
  411. "SingleTileImageryProvider.defaultHue",
  412. "SingleTileImageryProvider.defaultHue was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.hue instead."
  413. );
  414. this._defaultHue = value;
  415. },
  416. },
  417. /**
  418. * The default saturation of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 reduces the
  419. * saturation while greater than 1.0 increases it.
  420. * @memberof SingleTileImageryProvider.prototype
  421. * @type {Number|undefined}
  422. * @deprecated
  423. */
  424. defaultSaturation: {
  425. get: function () {
  426. deprecationWarning(
  427. "SingleTileImageryProvider.defaultSaturation",
  428. "SingleTileImageryProvider.defaultSaturation was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.saturation instead."
  429. );
  430. return this._defaultSaturation;
  431. },
  432. set: function (value) {
  433. deprecationWarning(
  434. "SingleTileImageryProvider.defaultSaturation",
  435. "SingleTileImageryProvider.defaultSaturation was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.saturation instead."
  436. );
  437. this._defaultSaturation = value;
  438. },
  439. },
  440. /**
  441. * The default gamma correction to apply to this provider. 1.0 uses the unmodified imagery color.
  442. * @memberof SingleTileImageryProvider.prototype
  443. * @type {Number|undefined}
  444. * @deprecated
  445. */
  446. defaultGamma: {
  447. get: function () {
  448. deprecationWarning(
  449. "SingleTileImageryProvider.defaultGamma",
  450. "SingleTileImageryProvider.defaultGamma was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.gamma instead."
  451. );
  452. return this._defaultGamma;
  453. },
  454. set: function (value) {
  455. deprecationWarning(
  456. "SingleTileImageryProvider.defaultGamma",
  457. "SingleTileImageryProvider.defaultGamma was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.gamma instead."
  458. );
  459. this._defaultGamma = value;
  460. },
  461. },
  462. /**
  463. * The default texture minification filter to apply to this provider.
  464. * @memberof SingleTileImageryProvider.prototype
  465. * @type {TextureMinificationFilter}
  466. * @deprecated
  467. */
  468. defaultMinificationFilter: {
  469. get: function () {
  470. deprecationWarning(
  471. "SingleTileImageryProvider.defaultMinificationFilter",
  472. "SingleTileImageryProvider.defaultMinificationFilter was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.minificationFilter instead."
  473. );
  474. return this._defaultMinificationFilter;
  475. },
  476. set: function (value) {
  477. deprecationWarning(
  478. "SingleTileImageryProvider.defaultMinificationFilter",
  479. "SingleTileImageryProvider.defaultMinificationFilter was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.minificationFilter instead."
  480. );
  481. this._defaultMinificationFilter = value;
  482. },
  483. },
  484. /**
  485. * The default texture magnification filter to apply to this provider.
  486. * @memberof SingleTileImageryProvider.prototype
  487. * @type {TextureMagnificationFilter}
  488. * @deprecated
  489. */
  490. defaultMagnificationFilter: {
  491. get: function () {
  492. deprecationWarning(
  493. "SingleTileImageryProvider.defaultMagnificationFilter",
  494. "SingleTileImageryProvider.defaultMagnificationFilter was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.magnificationFilter instead."
  495. );
  496. return this._defaultMagnificationFilter;
  497. },
  498. set: function (value) {
  499. deprecationWarning(
  500. "SingleTileImageryProvider.defaultMagnificationFilter",
  501. "SingleTileImageryProvider.defaultMagnificationFilter was deprecated in CesiumJS 1.104. It will be in CesiumJS 1.107. Use ImageryLayer.magnificationFilter instead."
  502. );
  503. this._defaultMagnificationFilter = value;
  504. },
  505. },
  506. });
  507. function failure(resource, error, provider, previousError) {
  508. let message = `Failed to load image ${resource.url}`;
  509. if (defined(error) && defined(error.message)) {
  510. message += `: ${error.message}`;
  511. }
  512. const reportedError = TileProviderError.reportError(
  513. previousError,
  514. provider,
  515. defined(provider) ? provider._errorEvent : undefined,
  516. message,
  517. 0,
  518. 0,
  519. 0,
  520. error
  521. );
  522. if (reportedError.retry) {
  523. return doRequest(resource, provider, reportedError);
  524. }
  525. if (defined(provider)) {
  526. provider._hasError = true;
  527. }
  528. throw new RuntimeError(message);
  529. }
  530. async function doRequest(resource, provider, previousError) {
  531. try {
  532. const image = await ImageryProvider.loadImage(null, resource);
  533. return image;
  534. } catch (error) {
  535. return failure(resource, error, provider, previousError);
  536. }
  537. }
  538. /**
  539. * @typedef {Object} SingleTileImageryProvider.fromUrlOptions
  540. *
  541. * Initialization options for the SingleTileImageryProvider constructor when using SingleTileImageryProvider.fromUrl
  542. *
  543. * @property {Rectangle} [rectangle=Rectangle.MAX_VALUE] The rectangle, in radians, covered by the image.
  544. * @property {Credit|String} [credit] A credit for the data source, which is displayed on the canvas.
  545. * @property {Ellipsoid} [ellipsoid] The ellipsoid. If not specified, the WGS84 ellipsoid is used.
  546. */
  547. /**
  548. * Creates a provider for a single, top-level imagery tile. The single image is assumed to use a
  549. * @param {Resource|String} url The url for the tile
  550. * @param {SingleTileImageryProvider.fromUrlOptions} [options] Object describing initialization options.
  551. *
  552. * @example
  553. * const provider = await SingleTileImageryProvider.fromUrl("https://yoururl.com/image.png");
  554. */
  555. SingleTileImageryProvider.fromUrl = async function (url, options) {
  556. //>>includeStart('debug', pragmas.debug);
  557. Check.defined("url", url);
  558. //>>includeEnd('debug');
  559. const resource = Resource.createIfNeeded(url);
  560. const image = await doRequest(resource);
  561. options = defaultValue(options, defaultValue.EMPTY_OBJECT);
  562. const provider = new SingleTileImageryProvider({
  563. ...options,
  564. url: url,
  565. tileWidth: image.width,
  566. tileHeight: image.height,
  567. });
  568. provider._image = image;
  569. return provider;
  570. };
  571. /**
  572. * Gets the credits to be displayed when a given tile is displayed.
  573. *
  574. * @param {number} x The tile X coordinate.
  575. * @param {number} y The tile Y coordinate.
  576. * @param {number} level The tile level;
  577. * @returns {Credit[]} The credits to be displayed when the tile is displayed.
  578. */
  579. SingleTileImageryProvider.prototype.getTileCredits = function (x, y, level) {
  580. return undefined;
  581. };
  582. /**
  583. * Requests the image for a given tile.
  584. *
  585. * @param {number} x The tile X coordinate.
  586. * @param {number} y The tile Y coordinate.
  587. * @param {number} level The tile level.
  588. * @param {Request} [request] The request object. Intended for internal use only.
  589. * @returns {Promise.<ImageryTypes>|undefined} The resolved image
  590. */
  591. SingleTileImageryProvider.prototype.requestImage = async function (
  592. x,
  593. y,
  594. level,
  595. request
  596. ) {
  597. if (!this._hasError && !defined(this._image)) {
  598. const image = await doRequest(this._resource, this);
  599. this._image = image;
  600. TileProviderError.reportSuccess(this._errorEvent);
  601. return image;
  602. }
  603. return this._image;
  604. };
  605. /**
  606. * Picking features is not currently supported by this imagery provider, so this function simply returns
  607. * undefined.
  608. *
  609. * @param {number} x The tile X coordinate.
  610. * @param {number} y The tile Y coordinate.
  611. * @param {number} level The tile level.
  612. * @param {number} longitude The longitude at which to pick features.
  613. * @param {number} latitude The latitude at which to pick features.
  614. * @return {undefined} Undefined since picking is not supported.
  615. */
  616. SingleTileImageryProvider.prototype.pickFeatures = function (
  617. x,
  618. y,
  619. level,
  620. longitude,
  621. latitude
  622. ) {
  623. return undefined;
  624. };
  625. export default SingleTileImageryProvider;