jtBaseApp/node_modules/@cesium/engine/Source/DataSources/CheckerboardMaterialProperty.js

import Cartesian2 from "../Core/Cartesian2.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 createPropertyDescriptor from "./createPropertyDescriptor.js";
import Property from "./Property.js";

const defaultEvenColor = Color.WHITE;
const defaultOddColor = Color.BLACK;
const defaultRepeat = new Cartesian2(2.0, 2.0);

/**
 * A {@link MaterialProperty} that maps to checkerboard {@link Material} uniforms.
 * @alias CheckerboardMaterialProperty
 * @constructor
 *
 * @param {object} [options] Object with the following properties:
 * @param {Property|Color} [options.evenColor=Color.WHITE] A Property specifying the first {@link Color}.
 * @param {Property|Color} [options.oddColor=Color.BLACK] A Property specifying the second {@link Color}.
 * @param {Property|Cartesian2} [options.repeat=new Cartesian2(2.0, 2.0)] A {@link Cartesian2} Property specifying how many times the tiles repeat in each direction.
 */
function CheckerboardMaterialProperty(options) {
  options = defaultValue(options, defaultValue.EMPTY_OBJECT);

  this._definitionChanged = new Event();
  this._evenColor = undefined;
  this._evenColorSubscription = undefined;
  this._oddColor = undefined;
  this._oddColorSubscription = undefined;
  this._repeat = undefined;
  this._repeatSubscription = undefined;

  this.evenColor = options.evenColor;
  this.oddColor = options.oddColor;
  this.repeat = options.repeat;
}

Object.defineProperties(CheckerboardMaterialProperty.prototype, {
  /**
   * Gets a value indicating if this property is constant.  A property is considered
   * constant if getValue always returns the same result for the current definition.
   * @memberof CheckerboardMaterialProperty.prototype
   *
   * @type {boolean}
   * @readonly
   */
  isConstant: {
    get: function () {
      return (
        Property.isConstant(this._evenColor) && //
        Property.isConstant(this._oddColor) && //
        Property.isConstant(this._repeat)
      );
    },
  },

  /**
   * Gets the event that is raised whenever the definition of this property changes.
   * The definition is considered to have changed if a call to getValue would return
   * a different result for the same time.
   * @memberof CheckerboardMaterialProperty.prototype
   *
   * @type {Event}
   * @readonly
   */
  definitionChanged: {
    get: function () {
      return this._definitionChanged;
    },
  },

  /**
   * Gets or sets the Property specifying the first {@link Color}.
   * @memberof CheckerboardMaterialProperty.prototype
   * @type {Property|undefined}
   * @default Color.WHITE
   */
  evenColor: createPropertyDescriptor("evenColor"),

  /**
   * Gets or sets the Property specifying the second {@link Color}.
   * @memberof CheckerboardMaterialProperty.prototype
   * @type {Property|undefined}
   * @default Color.BLACK
   */
  oddColor: createPropertyDescriptor("oddColor"),

  /**
   * Gets or sets the {@link Cartesian2} Property specifying how many times the tiles repeat in each direction.
   * @memberof CheckerboardMaterialProperty.prototype
   * @type {Property|undefined}
   * @default new Cartesian2(2.0, 2.0)
   */
  repeat: createPropertyDescriptor("repeat"),
});

/**
 * Gets the {@link Material} type at the provided time.
 *
 * @param {JulianDate} time The time for which to retrieve the type.
 * @returns {string} The type of material.
 */
CheckerboardMaterialProperty.prototype.getType = function (time) {
  return "Checkerboard";
};

/**
 * Gets the value of the property at the provided time.
 *
 * @param {JulianDate} time The time for which to retrieve the value.
 * @param {object} [result] The object to store the value into, if omitted, a new instance is created and returned.
 * @returns {object} The modified result parameter or a new instance if the result parameter was not supplied.
 */
CheckerboardMaterialProperty.prototype.getValue = function (time, result) {
  if (!defined(result)) {
    result = {};
  }
  result.lightColor = Property.getValueOrClonedDefault(
    this._evenColor,
    time,
    defaultEvenColor,
    result.lightColor
  );
  result.darkColor = Property.getValueOrClonedDefault(
    this._oddColor,
    time,
    defaultOddColor,
    result.darkColor
  );
  result.repeat = Property.getValueOrDefault(this._repeat, time, defaultRepeat);
  return result;
};

/**
 * Compares this property to the provided property and returns
 * <code>true</code> if they are equal, <code>false</code> otherwise.
 *
 * @param {Property} [other] The other property.
 * @returns {boolean} <code>true</code> if left and right are equal, <code>false</code> otherwise.
 */
CheckerboardMaterialProperty.prototype.equals = function (other) {
  return (
    this === other || //
    (other instanceof CheckerboardMaterialProperty && //
      Property.equals(this._evenColor, other._evenColor) && //
      Property.equals(this._oddColor, other._oddColor) && //
      Property.equals(this._repeat, other._repeat))
  );
};
export default CheckerboardMaterialProperty;