text: import Cartesian3 from '../Core/Cartesian3.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 ReferenceFrame from '../Core/ReferenceFrame.js';
  import PositionProperty from './PositionProperty.js';
  
      /**
       * A {@link PositionProperty} whose value does not change in respect to the
       * {@link ReferenceFrame} in which is it defined.
       *
       * @alias ConstantPositionProperty
       * @constructor
       *
       * @param {Cartesian3} [value] The property value.
       * @param {ReferenceFrame} [referenceFrame=ReferenceFrame.FIXED] The reference frame in which the position is defined.
       */
      function ConstantPositionProperty(value, referenceFrame) {
          this._definitionChanged = new Event();
          this._value = Cartesian3.clone(value);
          this._referenceFrame = defaultValue(referenceFrame, ReferenceFrame.FIXED);
      }
  
      Object.defineProperties(ConstantPositionProperty.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 ConstantPositionProperty.prototype
           *
           * @type {Boolean}
           * @readonly
           */
          isConstant : {
              get : function() {
                  return !defined(this._value) || this._referenceFrame === ReferenceFrame.FIXED;
              }
          },
          /**
           * 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 ConstantPositionProperty.prototype
           *
           * @type {Event}
           * @readonly
           */
          definitionChanged : {
              get : function() {
                  return this._definitionChanged;
              }
          },
          /**
           * Gets the reference frame in which the position is defined.
           * @memberof ConstantPositionProperty.prototype
           * @type {ReferenceFrame}
           * @default ReferenceFrame.FIXED;
           */
          referenceFrame : {
              get : function() {
                  return this._referenceFrame;
              }
          }
      });
  
      /**
       * Gets the value of the property at the provided time in the fixed frame.
       *
       * @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.
       */
      ConstantPositionProperty.prototype.getValue = function(time, result) {
          return this.getValueInReferenceFrame(time, ReferenceFrame.FIXED, result);
      };
  
      /**
       * Sets the value of the property.
       *
       * @param {Cartesian3} value The property value.
       * @param {ReferenceFrame} [referenceFrame=this.referenceFrame] The reference frame in which the position is defined.
       */
      ConstantPositionProperty.prototype.setValue = function(value, referenceFrame) {
          var definitionChanged = false;
          if (!Cartesian3.equals(this._value, value)) {
              definitionChanged = true;
              this._value = Cartesian3.clone(value);
          }
          if (defined(referenceFrame) && this._referenceFrame !== referenceFrame) {
              definitionChanged = true;
              this._referenceFrame = referenceFrame;
          }
          if (definitionChanged) {
              this._definitionChanged.raiseEvent(this);
          }
      };
  
      /**
       * Gets the value of the property at the provided time and in the provided reference frame.
       *
       * @param {JulianDate} time The time for which to retrieve the value.
       * @param {ReferenceFrame} referenceFrame The desired referenceFrame of the result.
       * @param {Cartesian3} [result] The object to store the value into, if omitted, a new instance is created and returned.
       * @returns {Cartesian3} The modified result parameter or a new instance if the result parameter was not supplied.
       */
      ConstantPositionProperty.prototype.getValueInReferenceFrame = function(time, referenceFrame, result) {
          //>>includeStart('debug', pragmas.debug);
          if (!defined(time)) {
              throw new DeveloperError('time is required.');
          }
          if (!defined(referenceFrame)) {
              throw new DeveloperError('referenceFrame is required.');
          }
          //>>includeEnd('debug');
  
          return PositionProperty.convertToReferenceFrame(time, this._value, this._referenceFrame, referenceFrame, 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.
       */
      ConstantPositionProperty.prototype.equals = function(other) {
          return this === other ||
                 (other instanceof ConstantPositionProperty &&
                  Cartesian3.equals(this._value, other._value) &&
                  this._referenceFrame === other._referenceFrame);
      };
  export default ConstantPositionProperty;
  