text: define([
          '../Core/ApproximateTerrainHeights',
          '../Core/Cartesian3',
          '../Core/Cartographic',
          '../Core/Check',
          '../Core/Color',
          '../Core/ColorGeometryInstanceAttribute',
          '../Core/defined',
          '../Core/DeveloperError',
          '../Core/DistanceDisplayConditionGeometryInstanceAttribute',
          '../Core/Ellipsoid',
          '../Core/GeometryInstance',
          '../Core/GeometryOffsetAttribute',
          '../Core/Iso8601',
          '../Core/OffsetGeometryInstanceAttribute',
          '../Core/Rectangle',
          '../Core/RectangleGeometry',
          '../Core/RectangleOutlineGeometry',
          '../Core/ShowGeometryInstanceAttribute',
          '../Scene/GroundPrimitive',
          '../Scene/HeightReference',
          '../Scene/MaterialAppearance',
          '../Scene/PerInstanceColorAppearance',
          './ColorMaterialProperty',
          './DynamicGeometryUpdater',
          './GeometryUpdater',
          './GroundGeometryUpdater',
          './Property'
      ], function(
          ApproximateTerrainHeights,
          Cartesian3,
          Cartographic,
          Check,
          Color,
          ColorGeometryInstanceAttribute,
          defined,
          DeveloperError,
          DistanceDisplayConditionGeometryInstanceAttribute,
          Ellipsoid,
          GeometryInstance,
          GeometryOffsetAttribute,
          Iso8601,
          OffsetGeometryInstanceAttribute,
          Rectangle,
          RectangleGeometry,
          RectangleOutlineGeometry,
          ShowGeometryInstanceAttribute,
          GroundPrimitive,
          HeightReference,
          MaterialAppearance,
          PerInstanceColorAppearance,
          ColorMaterialProperty,
          DynamicGeometryUpdater,
          GeometryUpdater,
          GroundGeometryUpdater,
          Property) {
      'use strict';
  
      var scratchColor = new Color();
      var defaultOffset = Cartesian3.ZERO;
      var offsetScratch = new Cartesian3();
      var scratchRectangle = new Rectangle();
      var scratchCenterRect = new Rectangle();
      var scratchCarto = new Cartographic();
  
      function RectangleGeometryOptions(entity) {
          this.id = entity;
          this.vertexFormat = undefined;
          this.rectangle = undefined;
          this.height = undefined;
          this.extrudedHeight = undefined;
          this.granularity = undefined;
          this.stRotation = undefined;
          this.rotation = undefined;
          this.offsetAttribute = undefined;
      }
  
      /**
       * A {@link GeometryUpdater} for rectangles.
       * Clients do not normally create this class directly, but instead rely on {@link DataSourceDisplay}.
       * @alias RectangleGeometryUpdater
       * @constructor
       *
       * @param {Entity} entity The entity containing the geometry to be visualized.
       * @param {Scene} scene The scene where visualization is taking place.
       */
      function RectangleGeometryUpdater(entity, scene) {
          GroundGeometryUpdater.call(this, {
              entity : entity,
              scene : scene,
              geometryOptions : new RectangleGeometryOptions(entity),
              geometryPropertyName : 'rectangle',
              observedPropertyNames : ['availability', 'rectangle']
          });
  
          this._onEntityPropertyChanged(entity, 'rectangle', entity.rectangle, undefined);
      }
  
      if (defined(Object.create)) {
          RectangleGeometryUpdater.prototype = Object.create(GroundGeometryUpdater.prototype);
          RectangleGeometryUpdater.prototype.constructor = RectangleGeometryUpdater;
      }
  
      /**
       * Creates the geometry instance which represents the fill of the geometry.
       *
       * @param {JulianDate} time The time to use when retrieving initial attribute values.
       * @returns {GeometryInstance} The geometry instance representing the filled portion of the geometry.
       *
       * @exception {DeveloperError} This instance does not represent a filled geometry.
       */
      RectangleGeometryUpdater.prototype.createFillGeometryInstance = function(time) {
          //>>includeStart('debug', pragmas.debug);
          Check.defined('time', time);
  
          if (!this._fillEnabled) {
              throw new DeveloperError('This instance does not represent a filled geometry.');
          }
          //>>includeEnd('debug');
  
          var entity = this._entity;
          var isAvailable = entity.isAvailable(time);
  
          var attributes = {
              show : new ShowGeometryInstanceAttribute(isAvailable && entity.isShowing && this._showProperty.getValue(time) && this._fillProperty.getValue(time)),
              distanceDisplayCondition : DistanceDisplayConditionGeometryInstanceAttribute.fromDistanceDisplayCondition(this._distanceDisplayConditionProperty.getValue(time)),
              offset : undefined,
              color : undefined
          };
  
          if (this._materialProperty instanceof ColorMaterialProperty) {
              var currentColor;
              if (defined(this._materialProperty.color) && (this._materialProperty.color.isConstant || isAvailable)) {
                  currentColor = this._materialProperty.color.getValue(time, scratchColor);
              }
              if (!defined(currentColor)) {
                  currentColor = Color.WHITE;
              }
              attributes.color = ColorGeometryInstanceAttribute.fromColor(currentColor);
          }
          if (defined(this._options.offsetAttribute)) {
              attributes.offset = OffsetGeometryInstanceAttribute.fromCartesian3(Property.getValueOrDefault(this._terrainOffsetProperty, time, defaultOffset, offsetScratch));
          }
  
          return new GeometryInstance({
              id : entity,
              geometry : new RectangleGeometry(this._options),
              attributes : attributes
          });
      };
  
      /**
       * Creates the geometry instance which represents the outline of the geometry.
       *
       * @param {JulianDate} time The time to use when retrieving initial attribute values.
       * @returns {GeometryInstance} The geometry instance representing the outline portion of the geometry.
       *
       * @exception {DeveloperError} This instance does not represent an outlined geometry.
       */
      RectangleGeometryUpdater.prototype.createOutlineGeometryInstance = function(time) {
          //>>includeStart('debug', pragmas.debug);
          Check.defined('time', time);
  
          if (!this._outlineEnabled) {
              throw new DeveloperError('This instance does not represent an outlined geometry.');
          }
          //>>includeEnd('debug');
  
          var entity = this._entity;
          var isAvailable = entity.isAvailable(time);
          var outlineColor = Property.getValueOrDefault(this._outlineColorProperty, time, Color.BLACK, scratchColor);
          var distanceDisplayCondition = this._distanceDisplayConditionProperty.getValue(time);
  
          var attributes = {
              show : new ShowGeometryInstanceAttribute(isAvailable && entity.isShowing && this._showProperty.getValue(time) && this._showOutlineProperty.getValue(time)),
              color : ColorGeometryInstanceAttribute.fromColor(outlineColor),
              distanceDisplayCondition : DistanceDisplayConditionGeometryInstanceAttribute.fromDistanceDisplayCondition(distanceDisplayCondition),
              offset : undefined
          };
  
          if (defined(this._options.offsetAttribute)) {
              attributes.offset = OffsetGeometryInstanceAttribute.fromCartesian3(Property.getValueOrDefault(this._terrainOffsetProperty, time, defaultOffset, offsetScratch));
          }
  
          return new GeometryInstance({
              id : entity,
              geometry : new RectangleOutlineGeometry(this._options),
              attributes : attributes
          });
      };
  
      RectangleGeometryUpdater.prototype._computeCenter = function(time, result) {
          var rect = Property.getValueOrUndefined(this._entity.rectangle.coordinates, time, scratchCenterRect);
          if (!defined(rect)) {
              return;
          }
          var center = Rectangle.center(rect, scratchCarto);
          return Cartographic.toCartesian(center, Ellipsoid.WGS84, result);
      };
  
      RectangleGeometryUpdater.prototype._isHidden = function(entity, rectangle) {
          return !defined(rectangle.coordinates) || GeometryUpdater.prototype._isHidden.call(this, entity, rectangle);
      };
  
      RectangleGeometryUpdater.prototype._isDynamic = function(entity, rectangle) {
          return !rectangle.coordinates.isConstant || //
                 !Property.isConstant(rectangle.height) || //
                 !Property.isConstant(rectangle.extrudedHeight) || //
                 !Property.isConstant(rectangle.granularity) || //
                 !Property.isConstant(rectangle.stRotation) || //
                 !Property.isConstant(rectangle.rotation) || //
                 !Property.isConstant(rectangle.outlineWidth) || //
                 !Property.isConstant(rectangle.zIndex) || //
                 (this._onTerrain && !Property.isConstant(this._materialProperty));
      };
  
      RectangleGeometryUpdater.prototype._setStaticOptions = function(entity, rectangle) {
          var isColorMaterial = this._materialProperty instanceof ColorMaterialProperty;
  
          var heightValue = Property.getValueOrUndefined(rectangle.height, Iso8601.MINIMUM_VALUE);
          var heightReferenceValue = Property.getValueOrDefault(rectangle.heightReference, Iso8601.MINIMUM_VALUE, HeightReference.NONE);
          var extrudedHeightValue = Property.getValueOrUndefined(rectangle.extrudedHeight, Iso8601.MINIMUM_VALUE);
          var extrudedHeightReferenceValue = Property.getValueOrDefault(rectangle.extrudedHeightReference, Iso8601.MINIMUM_VALUE, HeightReference.NONE);
          if (defined(extrudedHeightValue) && !defined(heightValue)) {
              heightValue = 0;
          }
  
          var options = this._options;
          options.vertexFormat = isColorMaterial ? PerInstanceColorAppearance.VERTEX_FORMAT : MaterialAppearance.MaterialSupport.TEXTURED.vertexFormat;
          options.rectangle = rectangle.coordinates.getValue(Iso8601.MINIMUM_VALUE, options.rectangle);
          options.granularity = Property.getValueOrUndefined(rectangle.granularity, Iso8601.MINIMUM_VALUE);
          options.stRotation = Property.getValueOrUndefined(rectangle.stRotation, Iso8601.MINIMUM_VALUE);
          options.rotation = Property.getValueOrUndefined(rectangle.rotation, Iso8601.MINIMUM_VALUE);
          options.offsetAttribute = GroundGeometryUpdater.computeGeometryOffsetAttribute(heightValue, heightReferenceValue, extrudedHeightValue, extrudedHeightReferenceValue);
          options.height = GroundGeometryUpdater.getGeometryHeight(heightValue, heightReferenceValue);
  
          extrudedHeightValue = GroundGeometryUpdater.getGeometryExtrudedHeight(extrudedHeightValue, extrudedHeightReferenceValue);
          if (extrudedHeightValue === GroundGeometryUpdater.CLAMP_TO_GROUND) {
              extrudedHeightValue = ApproximateTerrainHeights.getMinimumMaximumHeights(RectangleGeometry.computeRectangle(options, scratchRectangle)).minimumTerrainHeight;
          }
  
          options.extrudedHeight = extrudedHeightValue;
      };
  
      RectangleGeometryUpdater.DynamicGeometryUpdater = DynamicRectangleGeometryUpdater;
  
      /**
       * @private
       */
      function DynamicRectangleGeometryUpdater(geometryUpdater, primitives, groundPrimitives) {
          DynamicGeometryUpdater.call(this, geometryUpdater, primitives, groundPrimitives);
      }
  
      if (defined(Object.create)) {
          DynamicRectangleGeometryUpdater.prototype = Object.create(DynamicGeometryUpdater.prototype);
          DynamicRectangleGeometryUpdater.prototype.constructor = DynamicRectangleGeometryUpdater;
      }
  
      DynamicRectangleGeometryUpdater.prototype._isHidden = function(entity, rectangle, time) {
          return  !defined(this._options.rectangle) || DynamicGeometryUpdater.prototype._isHidden.call(this, entity, rectangle, time);
      };
  
      DynamicRectangleGeometryUpdater.prototype._setOptions = function(entity, rectangle, time) {
          var options = this._options;
          var heightValue = Property.getValueOrUndefined(rectangle.height, time);
          var heightReferenceValue = Property.getValueOrDefault(rectangle.heightReference, time, HeightReference.NONE);
          var extrudedHeightValue = Property.getValueOrUndefined(rectangle.extrudedHeight, time);
          var extrudedHeightReferenceValue = Property.getValueOrDefault(rectangle.extrudedHeightReference, time, HeightReference.NONE);
          if (defined(extrudedHeightValue) && !defined(heightValue)) {
              heightValue = 0;
          }
  
          options.rectangle = Property.getValueOrUndefined(rectangle.coordinates, time, options.rectangle);
          options.granularity = Property.getValueOrUndefined(rectangle.granularity, time);
          options.stRotation = Property.getValueOrUndefined(rectangle.stRotation, time);
          options.rotation = Property.getValueOrUndefined(rectangle.rotation, time);
          options.offsetAttribute = GroundGeometryUpdater.computeGeometryOffsetAttribute(heightValue, heightReferenceValue, extrudedHeightValue, extrudedHeightReferenceValue);
          options.height = GroundGeometryUpdater.getGeometryHeight(heightValue, heightReferenceValue);
  
          extrudedHeightValue = GroundGeometryUpdater.getGeometryExtrudedHeight(extrudedHeightValue, extrudedHeightReferenceValue);
          if (extrudedHeightValue === GroundGeometryUpdater.CLAMP_TO_GROUND) {
              extrudedHeightValue = ApproximateTerrainHeights.getMinimumMaximumHeights(RectangleGeometry.computeRectangle(options, scratchRectangle)).minimumTerrainHeight;
          }
  
          options.extrudedHeight = extrudedHeightValue;
      };
  
      return RectangleGeometryUpdater;
  });
  