TileCoordinatesImageryProvider.js

import Color from "../Core/Color.js";
import defaultValue from "../Core/defaultValue.js";
import defined from "../Core/defined.js";
import Event from "../Core/Event.js";
import GeographicTilingScheme from "../Core/GeographicTilingScheme.js";
import when from "../ThirdParty/when.js";

/**
 * An {@link ImageryProvider} that draws a box around every rendered tile in the tiling scheme, and draws
 * a label inside it indicating the X, Y, Level coordinates of the tile.  This is mostly useful for
 * debugging terrain and imagery rendering problems.
 *
 * @alias TileCoordinatesImageryProvider
 * @constructor
 *
 * @param {Object} [options] Object with the following properties:
 * @param {TilingScheme} [options.tilingScheme=new GeographicTilingScheme()] The tiling scheme for which to draw tiles.
 * @param {Ellipsoid} [options.ellipsoid] The ellipsoid.  If the tilingScheme is specified,
 *                    this parameter is ignored and the tiling scheme's ellipsoid is used instead. If neither
 *                    parameter is specified, the WGS84 ellipsoid is used.
 * @param {Color} [options.color=Color.YELLOW] The color to draw the tile box and label.
 * @param {Number} [options.tileWidth=256] The width of the tile for level-of-detail selection purposes.
 * @param {Number} [options.tileHeight=256] The height of the tile for level-of-detail selection purposes.
 */
function TileCoordinatesImageryProvider(options) {
  options = defaultValue(options, defaultValue.EMPTY_OBJECT);

  this._tilingScheme = defined(options.tilingScheme)
    ? options.tilingScheme
    : new GeographicTilingScheme({ ellipsoid: options.ellipsoid });
  this._color = defaultValue(options.color, Color.YELLOW);
  this._errorEvent = new Event();
  this._tileWidth = defaultValue(options.tileWidth, 256);
  this._tileHeight = defaultValue(options.tileHeight, 256);
  this._readyPromise = when.resolve(true);
}

Object.defineProperties(TileCoordinatesImageryProvider.prototype, {
  /**
   * Gets the proxy used by this provider.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Proxy}
   * @readonly
   */
  proxy: {
    get: function () {
      return undefined;
    },
  },

  /**
   * Gets the width of each tile, in pixels. This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Number}
   * @readonly
   */
  tileWidth: {
    get: function () {
      return this._tileWidth;
    },
  },

  /**
   * Gets the height of each tile, in pixels.  This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Number}
   * @readonly
   */
  tileHeight: {
    get: function () {
      return this._tileHeight;
    },
  },

  /**
   * Gets the maximum level-of-detail that can be requested.  This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Number}
   * @readonly
   */
  maximumLevel: {
    get: function () {
      return undefined;
    },
  },

  /**
   * Gets the minimum level-of-detail that can be requested.  This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Number}
   * @readonly
   */
  minimumLevel: {
    get: function () {
      return undefined;
    },
  },

  /**
   * Gets the tiling scheme used by this provider.  This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {TilingScheme}
   * @readonly
   */
  tilingScheme: {
    get: function () {
      return this._tilingScheme;
    },
  },

  /**
   * Gets the rectangle, in radians, of the imagery provided by this instance.  This function should
   * not be called before {@link TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.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 TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {TileDiscardPolicy}
   * @readonly
   */
  tileDiscardPolicy: {
    get: function () {
      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 TileCoordinatesImageryProvider.prototype
   * @type {Event}
   * @readonly
   */
  errorEvent: {
    get: function () {
      return this._errorEvent;
    },
  },

  /**
   * Gets a value indicating whether or not the provider is ready for use.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Boolean}
   * @readonly
   */
  ready: {
    get: function () {
      return true;
    },
  },

  /**
   * Gets a promise that resolves to true when the provider is ready for use.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Promise.<Boolean>}
   * @readonly
   */
  readyPromise: {
    get: function () {
      return this._readyPromise;
    },
  },

  /**
   * 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 TileCoordinatesImageryProvider#ready} returns true.
   * @memberof TileCoordinatesImageryProvider.prototype
   * @type {Credit}
   * @readonly
   */
  credit: {
    get: function () {
      return undefined;
    },
  },

  /**
   * 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.  Setting this property to false reduces memory usage
   * and texture upload time.
   * @memberof TileCoordinatesImageryProvider.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.
 */
TileCoordinatesImageryProvider.prototype.getTileCredits = function (
  x,
  y,
  level
) {
  return undefined;
};

/**
 * Requests the image for a given tile.  This function should
 * not be called before {@link TileCoordinatesImageryProvider#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.
 */
TileCoordinatesImageryProvider.prototype.requestImage = function (
  x,
  y,
  level,
  request
) {
  var canvas = document.createElement("canvas");
  canvas.width = 256;
  canvas.height = 256;
  var context = canvas.getContext("2d");

  var cssColor = this._color.toCssColorString();

  context.strokeStyle = cssColor;
  context.lineWidth = 2;
  context.strokeRect(1, 1, 255, 255);

  context.font = "bold 25px Arial";
  context.textAlign = "center";
  context.fillStyle = cssColor;
  context.fillText("L: " + level, 124, 86);
  context.fillText("X: " + x, 124, 136);
  context.fillText("Y: " + y, 124, 186);

  return canvas;
};

/**
 * 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.
 */
TileCoordinatesImageryProvider.prototype.pickFeatures = function (
  x,
  y,
  level,
  longitude,
  latitude
) {
  return undefined;
};
export default TileCoordinatesImageryProvider;