text: /*global define*/
  define([
          './BoundingSphere',
          './Cartesian2',
          './Cartesian3',
          './Cartographic',
          './ComponentDatatype',
          './defaultValue',
          './defined',
          './DeveloperError',
          './EllipseGeometryLibrary',
          './Ellipsoid',
          './GeographicProjection',
          './Geometry',
          './GeometryAttribute',
          './GeometryAttributes',
          './GeometryInstance',
          './GeometryPipeline',
          './IndexDatatype',
          './Math',
          './Matrix3',
          './PrimitiveType',
          './Quaternion',
          './VertexFormat'
      ], function(
          BoundingSphere,
          Cartesian2,
          Cartesian3,
          Cartographic,
          ComponentDatatype,
          defaultValue,
          defined,
          DeveloperError,
          EllipseGeometryLibrary,
          Ellipsoid,
          GeographicProjection,
          Geometry,
          GeometryAttribute,
          GeometryAttributes,
          GeometryInstance,
          GeometryPipeline,
          IndexDatatype,
          CesiumMath,
          Matrix3,
          PrimitiveType,
          Quaternion,
          VertexFormat) {
      "use strict";
  
      var scratchCartesian1 = new Cartesian3();
      var scratchCartesian2 = new Cartesian3();
      var scratchCartesian3 = new Cartesian3();
      var scratchCartesian4 = new Cartesian3();
      var texCoordScratch = new Cartesian2();
      var textureMatrixScratch = new Matrix3();
      var quaternionScratch = new Quaternion();
  
      var scratchNormal = new Cartesian3();
      var scratchTangent = new Cartesian3();
      var scratchBinormal = new Cartesian3();
  
      var scratchCartographic = new Cartographic();
      var projectedCenterScratch = new Cartesian3();
  
      function computeTopBottomAttributes(positions, options, extrude) {
          var vertexFormat = options.vertexFormat;
          var center = options.center;
          var semiMajorAxis = options.semiMajorAxis;
          var ellipsoid = options.ellipsoid;
          var stRotation = options.stRotation;
          var size = (extrude) ? positions.length / 3 * 2 : positions.length / 3;
  
          var textureCoordinates = (vertexFormat.st) ? new Float32Array(size * 2) : undefined;
          var normals = (vertexFormat.normal) ? new Float32Array(size * 3) : undefined;
          var tangents = (vertexFormat.tangent) ? new Float32Array(size * 3) : undefined;
          var binormals = (vertexFormat.binormal) ? new Float32Array(size * 3) : undefined;
  
          var textureCoordIndex = 0;
  
          // Raise positions to a height above the ellipsoid and compute the
          // texture coordinates, normals, tangents, and binormals.
          var normal = scratchNormal;
          var tangent = scratchTangent;
          var binormal = scratchBinormal;
  
          var projection = new GeographicProjection(ellipsoid);
          var projectedCenter = projection.project(ellipsoid.cartesianToCartographic(center, scratchCartographic), projectedCenterScratch);
  
          var geodeticNormal = ellipsoid.scaleToGeodeticSurface(center, scratchCartesian1);
          ellipsoid.geodeticSurfaceNormal(geodeticNormal, geodeticNormal);
          var rotation = Quaternion.fromAxisAngle(geodeticNormal, stRotation, quaternionScratch);
          var textureMatrix = Matrix3.fromQuaternion(rotation, textureMatrixScratch);
  
          var length = positions.length;
          var bottomOffset = (extrude) ? length : 0;
          var stOffset = bottomOffset / 3 * 2;
          for ( var i = 0; i < length; i += 3) {
              var i1 = i + 1;
              var i2 = i + 2;
              var position = Cartesian3.fromArray(positions, i, scratchCartesian1);
  
              if (vertexFormat.st) {
                  var rotatedPoint = Matrix3.multiplyByVector(textureMatrix, position, scratchCartesian2);
                  var projectedPoint = projection.project(ellipsoid.cartesianToCartographic(rotatedPoint, scratchCartographic), scratchCartesian3);
                  Cartesian3.subtract(projectedPoint, projectedCenter, projectedPoint);
  
                  texCoordScratch.x = (projectedPoint.x + semiMajorAxis) / (2.0 * semiMajorAxis);
                  texCoordScratch.y = (projectedPoint.y + semiMajorAxis) / (2.0 * semiMajorAxis);
  
                  if (extrude) {
                      textureCoordinates[textureCoordIndex + stOffset] = texCoordScratch.x;
                      textureCoordinates[textureCoordIndex + 1 + stOffset] = texCoordScratch.y;
                  }
  
                  textureCoordinates[textureCoordIndex++] = texCoordScratch.x;
                  textureCoordinates[textureCoordIndex++] = texCoordScratch.y;
              }
  
              normal = ellipsoid.geodeticSurfaceNormal(position, normal);
  
              if (vertexFormat.normal || vertexFormat.tangent || vertexFormat.binormal) {
                  if (vertexFormat.tangent || vertexFormat.binormal) {
                      tangent = Cartesian3.cross(Cartesian3.UNIT_Z, normal, tangent);
                      Matrix3.multiplyByVector(textureMatrix, tangent, tangent);
                  }
                  if (vertexFormat.normal) {
                      normals[i] = normal.x;
                      normals[i1] = normal.y;
                      normals[i2] = normal.z;
                      if (extrude) {
                          normals[i + bottomOffset] = -normal.x;
                          normals[i1 + bottomOffset] = -normal.y;
                          normals[i2 + bottomOffset] = -normal.z;
                      }
                  }
  
                  if (vertexFormat.tangent) {
                      tangents[i] = tangent.x;
                      tangents[i1] = tangent.y;
                      tangents[i2] = tangent.z;
                      if (extrude) {
                          tangents[i + bottomOffset] = -tangent.x;
                          tangents[i1 + bottomOffset] = -tangent.y;
                          tangents[i2 + bottomOffset] = -tangent.z;
                      }
                  }
  
                  if (vertexFormat.binormal) {
                      binormal = Cartesian3.cross(normal, tangent, binormal);
                      binormals[i] = binormal.x;
                      binormals[i1] = binormal.y;
                      binormals[i2] = binormal.z;
                      if (extrude) {
                          binormals[i + bottomOffset] = binormal.x;
                          binormals[i1 + bottomOffset] = binormal.y;
                          binormals[i2 + bottomOffset] = binormal.z;
                      }
                  }
              }
          }
  
          var attributes = new GeometryAttributes();
  
          if (vertexFormat.position) {
              var finalPositions = EllipseGeometryLibrary.raisePositionsToHeight(positions, options, extrude);
              attributes.position = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.DOUBLE,
                  componentsPerAttribute : 3,
                  values : finalPositions
              });
          }
  
          if (vertexFormat.st) {
              attributes.st = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 2,
                  values : textureCoordinates
              });
          }
  
          if (vertexFormat.normal) {
              attributes.normal = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : normals
              });
          }
  
          if (vertexFormat.tangent) {
              attributes.tangent = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : tangents
              });
          }
  
          if (vertexFormat.binormal) {
              attributes.binormal = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : binormals
              });
          }
          return attributes;
      }
  
  
      function topIndices(numPts) {
          // The number of triangles in the ellipse on the positive x half-space and for
          // the column of triangles in the middle is:
          //
          // numTriangles = 4 + 8 + 12 + ... = 4 + (4 + 4) + (4 + 4 + 4) + ... = 4 * (1 + 2 + 3 + ...)
          //              = 4 * ((n * ( n + 1)) / 2)
          // numColumnTriangles = 2 * 2 * n
          // total = 2 * numTrangles + numcolumnTriangles
          //
          // Substitute (numPts - 1.0) for n above
          var indices = new Array(2 * numPts * (numPts + 1));
          var indicesIndex = 0;
          var prevIndex;
          var numInterior;
          var positionIndex;
          var i;
          var j;
          // Indices triangles to the 'left' of the north vector
          for (i = 1; i < numPts; ++i) {
              positionIndex = i * (i + 1);
              prevIndex = (i - 1) * i;
  
              indices[indicesIndex++] = positionIndex++;
              indices[indicesIndex++] = prevIndex;
              indices[indicesIndex++] = positionIndex;
  
              numInterior = 2 * i;
              for (j = 0; j < numInterior - 1; ++j) {
  
                  indices[indicesIndex++] = positionIndex;
                  indices[indicesIndex++] = prevIndex++;
                  indices[indicesIndex++] = prevIndex;
  
                  indices[indicesIndex++] = positionIndex++;
                  indices[indicesIndex++] = prevIndex;
                  indices[indicesIndex++] = positionIndex;
              }
  
              indices[indicesIndex++] = positionIndex++;
              indices[indicesIndex++] = prevIndex;
              indices[indicesIndex++] = positionIndex;
          }
  
          // Indices for central column of triangles
          numInterior = numPts * 2;
          ++positionIndex;
          ++prevIndex;
          for (i = 0; i < numInterior - 1; ++i) {
              indices[indicesIndex++] = positionIndex;
              indices[indicesIndex++] = prevIndex++;
              indices[indicesIndex++] = prevIndex;
  
              indices[indicesIndex++] = positionIndex++;
              indices[indicesIndex++] = prevIndex;
              indices[indicesIndex++] = positionIndex;
          }
  
          // Reverse the process creating indices to the 'right' of the north vector
          ++prevIndex;
          ++positionIndex;
          for (i = numPts - 1; i > 0; --i) {
              indices[indicesIndex++] = prevIndex++;
              indices[indicesIndex++] = prevIndex;
              indices[indicesIndex++] = positionIndex;
  
              numInterior = 2 * i;
              for (j = 0; j < numInterior - 1; ++j) {
                  indices[indicesIndex++] = positionIndex;
                  indices[indicesIndex++] = prevIndex++;
                  indices[indicesIndex++] = prevIndex;
  
                  indices[indicesIndex++] = positionIndex++;
                  indices[indicesIndex++] = prevIndex;
                  indices[indicesIndex++] = positionIndex;
              }
  
              indices[indicesIndex++] = prevIndex++;
              indices[indicesIndex++] = prevIndex++;
              indices[indicesIndex++] = positionIndex++;
          }
          return indices;
      }
  
      var boundingSphereCenter = new Cartesian3();
      function computeEllipse(options) {
          var center = options.center;
          boundingSphereCenter = Cartesian3.multiplyByScalar(options.ellipsoid.geodeticSurfaceNormal(center, boundingSphereCenter), options.height, boundingSphereCenter);
          boundingSphereCenter = Cartesian3.add(center, boundingSphereCenter, boundingSphereCenter);
          var boundingSphere = new BoundingSphere(boundingSphereCenter, options.semiMajorAxis);
          var cep = EllipseGeometryLibrary.computeEllipsePositions(options, true, false);
          var positions = cep.positions;
          var numPts = cep.numPts;
          var attributes = computeTopBottomAttributes(positions, options, false);
          var indices = topIndices(numPts);
          indices = IndexDatatype.createTypedArray(positions.length / 3, indices);
          return {
              boundingSphere : boundingSphere,
              attributes : attributes,
              indices : indices
          };
      }
  
      function computeWallAttributes(positions, options) {
          var vertexFormat = options.vertexFormat;
          var center = options.center;
          var semiMajorAxis = options.semiMajorAxis;
          var ellipsoid = options.ellipsoid;
          var height = options.height;
          var extrudedHeight = options.extrudedHeight;
          var stRotation = options.stRotation;
          var size = positions.length / 3 * 2;
  
          var finalPositions = new Float64Array(size * 3);
          var textureCoordinates = (vertexFormat.st) ? new Float32Array(size * 2) : undefined;
          var normals = (vertexFormat.normal) ? new Float32Array(size * 3) : undefined;
          var tangents = (vertexFormat.tangent) ? new Float32Array(size * 3) : undefined;
          var binormals = (vertexFormat.binormal) ? new Float32Array(size * 3) : undefined;
  
          var textureCoordIndex = 0;
  
          // Raise positions to a height above the ellipsoid and compute the
          // texture coordinates, normals, tangents, and binormals.
          var normal = scratchNormal;
          var tangent = scratchTangent;
          var binormal = scratchBinormal;
  
          var projection = new GeographicProjection(ellipsoid);
          var projectedCenter = projection.project(ellipsoid.cartesianToCartographic(center, scratchCartographic), projectedCenterScratch);
  
          var geodeticNormal = ellipsoid.scaleToGeodeticSurface(center, scratchCartesian1);
          ellipsoid.geodeticSurfaceNormal(geodeticNormal, geodeticNormal);
          var rotation = Quaternion.fromAxisAngle(geodeticNormal, stRotation, quaternionScratch);
          var textureMatrix = Matrix3.fromQuaternion(rotation, textureMatrixScratch);
  
          var length = positions.length;
          var stOffset = length / 3 * 2;
          for ( var i = 0; i < length; i += 3) {
              var i1 = i + 1;
              var i2 = i + 2;
              var position = Cartesian3.fromArray(positions, i, scratchCartesian1);
              var extrudedPosition;
  
              if (vertexFormat.st) {
                  var rotatedPoint = Matrix3.multiplyByVector(textureMatrix, position, scratchCartesian2);
                  var projectedPoint = projection.project(ellipsoid.cartesianToCartographic(rotatedPoint, scratchCartographic), scratchCartesian3);
                  Cartesian3.subtract(projectedPoint, projectedCenter, projectedPoint);
  
                  texCoordScratch.x = (projectedPoint.x + semiMajorAxis) / (2.0 * semiMajorAxis);
                  texCoordScratch.y = (projectedPoint.y + semiMajorAxis) / (2.0 * semiMajorAxis);
  
                  textureCoordinates[textureCoordIndex + stOffset] = texCoordScratch.x;
                  textureCoordinates[textureCoordIndex + 1 + stOffset] = texCoordScratch.y;
  
                  textureCoordinates[textureCoordIndex++] = texCoordScratch.x;
                  textureCoordinates[textureCoordIndex++] = texCoordScratch.y;
              }
  
              position = ellipsoid.scaleToGeodeticSurface(position, position);
              extrudedPosition = Cartesian3.clone(position, scratchCartesian2);
              normal = ellipsoid.geodeticSurfaceNormal(position, normal);
              var scaledNormal = Cartesian3.multiplyByScalar(normal, height, scratchCartesian4);
              position = Cartesian3.add(position, scaledNormal, position);
              scaledNormal = Cartesian3.multiplyByScalar(normal, extrudedHeight, scaledNormal);
              extrudedPosition = Cartesian3.add(extrudedPosition, scaledNormal, extrudedPosition);
  
              if (vertexFormat.position) {
                  finalPositions[i + length] = extrudedPosition.x;
                  finalPositions[i1 + length] = extrudedPosition.y;
                  finalPositions[i2 + length] = extrudedPosition.z;
  
                  finalPositions[i] = position.x;
                  finalPositions[i1] = position.y;
                  finalPositions[i2] = position.z;
              }
  
              if (vertexFormat.normal || vertexFormat.tangent || vertexFormat.binormal) {
  
                  binormal = Cartesian3.clone(normal, binormal);
                  var next = Cartesian3.fromArray(positions, (i + 3) % length, scratchCartesian4);
                  Cartesian3.subtract(next, position, next);
                  var bottom = Cartesian3.subtract(extrudedPosition, position, scratchCartesian3);
  
                  normal = Cartesian3.normalize(Cartesian3.cross(bottom, next, normal), normal);
  
                  if (vertexFormat.normal) {
                      normals[i] = normal.x;
                      normals[i1] = normal.y;
                      normals[i2] = normal.z;
  
                      normals[i + length] = normal.x;
                      normals[i1 + length] = normal.y;
                      normals[i2 + length] = normal.z;
                  }
  
                  if (vertexFormat.tangent) {
                      tangent = Cartesian3.normalize(Cartesian3.cross(binormal, normal, tangent), tangent);
                      tangents[i] = tangent.x;
                      tangents[i1] = tangent.y;
                      tangents[i2] = tangent.z;
  
                      tangents[i + length] = tangent.x;
                      tangents[i + 1 + length] = tangent.y;
                      tangents[i + 2 + length] = tangent.z;
                  }
  
                  if (vertexFormat.binormal) {
                      binormals[i] = binormal.x;
                      binormals[i1] = binormal.y;
                      binormals[i2] = binormal.z;
  
                      binormals[i + length] = binormal.x;
                      binormals[i1 + length] = binormal.y;
                      binormals[i2 + length] = binormal.z;
                  }
              }
          }
  
          var attributes = new GeometryAttributes();
  
          if (vertexFormat.position) {
              attributes.position = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.DOUBLE,
                  componentsPerAttribute : 3,
                  values : finalPositions
              });
          }
  
          if (vertexFormat.st) {
              attributes.st = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 2,
                  values : textureCoordinates
              });
          }
  
          if (vertexFormat.normal) {
              attributes.normal = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : normals
              });
          }
  
          if (vertexFormat.tangent) {
              attributes.tangent = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : tangents
              });
          }
  
          if (vertexFormat.binormal) {
              attributes.binormal = new GeometryAttribute({
                  componentDatatype : ComponentDatatype.FLOAT,
                  componentsPerAttribute : 3,
                  values : binormals
              });
          }
          return attributes;
      }
  
      function computeWallIndices(positions) {
          var length = positions.length / 3;
          var indices = IndexDatatype.createTypedArray(length, length * 6);
          var index = 0;
          for (var i = 0; i < length; i++) {
              var UL = i;
              var LL = i + length;
              var UR = (UL + 1) % length;
              var LR = UR + length;
              indices[index++] = UL;
              indices[index++] = LL;
              indices[index++] = UR;
              indices[index++] = UR;
              indices[index++] = LL;
              indices[index++] = LR;
          }
  
          return indices;
      }
  
      var topBoundingSphere = new BoundingSphere();
      var bottomBoundingSphere = new BoundingSphere();
      function computeExtrudedEllipse(options) {
          var center = options.center;
          var ellipsoid = options.ellipsoid;
          var semiMajorAxis = options.semiMajorAxis;
          var scaledNormal = Cartesian3.multiplyByScalar(ellipsoid.geodeticSurfaceNormal(center, scratchCartesian1), options.height, scratchCartesian1);
          topBoundingSphere.center = Cartesian3.add(center, scaledNormal, topBoundingSphere.center);
          topBoundingSphere.radius = semiMajorAxis;
  
          scaledNormal = Cartesian3.multiplyByScalar(ellipsoid.geodeticSurfaceNormal(center, scaledNormal), options.extrudedHeight, scaledNormal);
          bottomBoundingSphere.center = Cartesian3.add(center, scaledNormal, bottomBoundingSphere.center);
          bottomBoundingSphere.radius = semiMajorAxis;
  
          var cep = EllipseGeometryLibrary.computeEllipsePositions(options, true, true);
          var positions = cep.positions;
          var numPts = cep.numPts;
          var outerPositions = cep.outerPositions;
          var boundingSphere = BoundingSphere.union(topBoundingSphere, bottomBoundingSphere);
          var topBottomAttributes = computeTopBottomAttributes(positions, options, true);
          var indices = topIndices(numPts);
          var length = indices.length;
          indices.length = length * 2;
          var posLength = positions.length / 3;
          for ( var i = 0; i < length; i += 3) {
              indices[i + length] = indices[i + 2] + posLength;
              indices[i + 1 + length] = indices[i + 1] + posLength;
              indices[i + 2 + length] = indices[i] + posLength;
          }
  
          var topBottomIndices = IndexDatatype.createTypedArray(posLength * 2 / 3, indices);
  
          var topBottomGeo = new Geometry({
              attributes : topBottomAttributes,
              indices : topBottomIndices,
              primitiveType : PrimitiveType.TRIANGLES
          });
  
          var wallAttributes = computeWallAttributes(outerPositions, options);
          indices = computeWallIndices(outerPositions);
          var wallIndices = IndexDatatype.createTypedArray(outerPositions.length * 2 / 3, indices);
  
          var wallGeo = new Geometry({
              attributes : wallAttributes,
              indices : wallIndices,
              primitiveType : PrimitiveType.TRIANGLES
          });
  
          var geo = GeometryPipeline.combineInstances([
              new GeometryInstance({
                  geometry : topBottomGeo
              }),
              new GeometryInstance({
                  geometry : wallGeo
              })
          ]);
  
          return {
              boundingSphere : boundingSphere,
              attributes : geo[0].attributes,
              indices : geo[0].indices
          };
      }
  
      /**
       * A description of an ellipse on an ellipsoid.
       *
       * @alias EllipseGeometry
       * @constructor
       *
       * @param {Object} options Object with the following properties:
       * @param {Cartesian3} options.center The ellipse's center point in the fixed frame.
       * @param {Number} options.semiMajorAxis The length of the ellipse's semi-major axis in meters.
       * @param {Number} options.semiMinorAxis The length of the ellipse's semi-minor axis in meters.
       * @param {Ellipsoid} [options.ellipsoid=Ellipsoid.WGS84] The ellipsoid the ellipse will be on.
       * @param {Number} [options.height=0.0] The height above the ellipsoid.
       * @param {Number} [options.extrudedHeight] The height of the extrusion.
       * @param {Number} [options.rotation=0.0] The angle from north (clockwise) in radians.
       * @param {Number} [options.stRotation=0.0] The rotation of the texture coordinates, in radians. A positive rotation is counter-clockwise.
       * @param {Number} [options.granularity=CesiumMath.RADIANS_PER_DEGREE] The angular distance between points on the ellipse in radians.
       * @param {VertexFormat} [options.vertexFormat=VertexFormat.DEFAULT] The vertex attributes to be computed.
       *
       * @exception {DeveloperError} semiMajorAxis and semiMinorAxis must be greater than zero.
       * @exception {DeveloperError} semiMajorAxis must be larger than the semiMinorAxis.
       * @exception {DeveloperError} granularity must be greater than zero.
       *
       * @see EllipseGeometry.createGeometry
       *
       * @demo {@link http://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Ellipse.html|Cesium Sandcastle Ellipse Demo}
       *
       * @example
       * // Create an ellipse.
       * var ellipse = new Cesium.EllipseGeometry({
       *   center : Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883),
       *   semiMajorAxis : 500000.0,
       *   semiMinorAxis : 300000.0,
       *   rotation : Cesium.Math.toRadians(60.0)
       * });
       * var geometry = Cesium.EllipseGeometry.createGeometry(ellipse);
       */
      var EllipseGeometry = function(options) {
          options = defaultValue(options, defaultValue.EMPTY_OBJECT);
  
          var center = options.center;
          var ellipsoid = defaultValue(options.ellipsoid, Ellipsoid.WGS84);
          var semiMajorAxis = options.semiMajorAxis;
          var semiMinorAxis = options.semiMinorAxis;
          var granularity = defaultValue(options.granularity, CesiumMath.RADIANS_PER_DEGREE);
          var height = defaultValue(options.height, 0.0);
          var extrudedHeight = options.extrudedHeight;
          var extrude = (defined(extrudedHeight) && Math.abs(height - extrudedHeight) > 1.0);
          var vertexFormat = defaultValue(options.vertexFormat, VertexFormat.DEFAULT);
  
          //>>includeStart('debug', pragmas.debug);
          if (!defined(center)) {
              throw new DeveloperError('center is required.');
          }
          if (!defined(semiMajorAxis)) {
              throw new DeveloperError('semiMajorAxis is required.');
          }
          if (!defined(semiMinorAxis)) {
              throw new DeveloperError('semiMinorAxis is required.');
          }
          if (semiMajorAxis <= 0.0 || semiMinorAxis <= 0.0) {
              throw new DeveloperError('Semi-major and semi-minor axes must be greater than zero.');
          }
          if (semiMajorAxis < semiMinorAxis) {
              throw new DeveloperError('semiMajorAxis must be larger than the semiMinorAxis.');
          }
          if (granularity <= 0.0) {
              throw new DeveloperError('granularity must be greater than zero.');
          }
          //>>includeEnd('debug');
  
          this._center = Cartesian3.clone(center);
          this._semiMajorAxis = semiMajorAxis;
          this._semiMinorAxis = semiMinorAxis;
          this._ellipsoid = Ellipsoid.clone(ellipsoid);
          this._rotation = defaultValue(options.rotation, 0.0);
          this._stRotation = defaultValue(options.stRotation, 0.0);
          this._height = height;
          this._granularity = granularity;
          this._vertexFormat = VertexFormat.clone(vertexFormat);
          this._extrudedHeight = defaultValue(extrudedHeight, height);
          this._extrude = extrude;
          this._workerName = 'createEllipseGeometry';
      };
  
      /**
       * The number of elements used to pack the object into an array.
       * @type {Number}
       */
      EllipseGeometry.packedLength = Cartesian3.packedLength + Ellipsoid.packedLength + VertexFormat.packedLength + 8;
  
      /**
       * Stores the provided instance into the provided array.
       * @function
       *
       * @param {Object} value The value to pack.
       * @param {Number[]} array The array to pack into.
       * @param {Number} [startingIndex=0] The index into the array at which to start packing the elements.
       */
      EllipseGeometry.pack = function(value, array, startingIndex) {
          //>>includeStart('debug', pragmas.debug);
          if (!defined(value)) {
              throw new DeveloperError('value is required');
          }
          if (!defined(array)) {
              throw new DeveloperError('array is required');
          }
          //>>includeEnd('debug');
  
          startingIndex = defaultValue(startingIndex, 0);
  
          Cartesian3.pack(value._center, array, startingIndex);
          startingIndex += Cartesian3.packedLength;
  
          Ellipsoid.pack(value._ellipsoid, array, startingIndex);
          startingIndex += Ellipsoid.packedLength;
  
          VertexFormat.pack(value._vertexFormat, array, startingIndex);
          startingIndex += VertexFormat.packedLength;
  
          array[startingIndex++] = value._semiMajorAxis;
          array[startingIndex++] = value._semiMinorAxis;
          array[startingIndex++] = value._rotation;
          array[startingIndex++] = value._stRotation;
          array[startingIndex++] = value._height;
          array[startingIndex++] = value._granularity;
          array[startingIndex++] = value._extrudedHeight;
          array[startingIndex]   = value._extrude ? 1.0 : 0.0;
      };
  
      var scratchCenter = new Cartesian3();
      var scratchEllipsoid = new Ellipsoid();
      var scratchVertexFormat = new VertexFormat();
      var scratchOptions = {
          center : scratchCenter,
          ellipsoid : scratchEllipsoid,
          vertexFormat : scratchVertexFormat,
          semiMajorAxis : undefined,
          semiMinorAxis : undefined,
          rotation : undefined,
          stRotation : undefined,
          height : undefined,
          granularity : undefined,
          extrudedHeight : undefined
      };
  
      /**
       * Retrieves an instance from a packed array.
       *
       * @param {Number[]} array The packed array.
       * @param {Number} [startingIndex=0] The starting index of the element to be unpacked.
       * @param {EllipseGeometry} [result] The object into which to store the result.
       */
      EllipseGeometry.unpack = function(array, startingIndex, result) {
          //>>includeStart('debug', pragmas.debug);
          if (!defined(array)) {
              throw new DeveloperError('array is required');
          }
          //>>includeEnd('debug');
  
          startingIndex = defaultValue(startingIndex, 0);
  
          var center = Cartesian3.unpack(array, startingIndex, scratchCenter);
          startingIndex += Cartesian3.packedLength;
  
          var ellipsoid = Ellipsoid.unpack(array, startingIndex, scratchEllipsoid);
          startingIndex += Ellipsoid.packedLength;
  
          var vertexFormat = VertexFormat.unpack(array, startingIndex, scratchVertexFormat);
          startingIndex += VertexFormat.packedLength;
  
          var semiMajorAxis = array[startingIndex++];
          var semiMinorAxis = array[startingIndex++];
          var rotation = array[startingIndex++];
          var stRotation = array[startingIndex++];
          var height = array[startingIndex++];
          var granularity = array[startingIndex++];
          var extrudedHeight = array[startingIndex++];
          var extrude = array[startingIndex] === 1.0;
  
          if (!defined(result)) {
              scratchOptions.height = height;
              scratchOptions.extrudedHeight = extrudedHeight;
              scratchOptions.granularity = granularity;
              scratchOptions.stRotation = stRotation;
              scratchOptions.rotation = rotation;
              scratchOptions.semiMajorAxis = semiMajorAxis;
              scratchOptions.semiMinorAxis = semiMinorAxis;
              return new EllipseGeometry(scratchOptions);
          }
  
          result._center = Cartesian3.clone(center, result._center);
          result._ellipsoid = Ellipsoid.clone(ellipsoid, result._ellipsoid);
          result._vertexFormat = VertexFormat.clone(vertexFormat, result._vertexFormat);
          result._semiMajorAxis = semiMajorAxis;
          result._semiMinorAxis = semiMinorAxis;
          result._rotation = rotation;
          result._stRotation = stRotation;
          result._height = height;
          result._granularity = granularity;
          result._extrudedHeight = extrudedHeight;
          result._extrude = extrude;
  
          return result;
      };
  
      /**
       * Computes the geometric representation of a ellipse on an ellipsoid, including its vertices, indices, and a bounding sphere.
       *
       * @param {EllipseGeometry} ellipseGeometry A description of the ellipse.
       * @returns {Geometry} The computed vertices and indices.
       */
      EllipseGeometry.createGeometry = function(ellipseGeometry) {
          ellipseGeometry._center = ellipseGeometry._ellipsoid.scaleToGeodeticSurface(ellipseGeometry._center, ellipseGeometry._center);
          var options = {
              center : ellipseGeometry._center,
              semiMajorAxis : ellipseGeometry._semiMajorAxis,
              semiMinorAxis : ellipseGeometry._semiMinorAxis,
              ellipsoid : ellipseGeometry._ellipsoid,
              rotation : ellipseGeometry._rotation,
              height : ellipseGeometry._height,
              extrudedHeight : ellipseGeometry._extrudedHeight,
              granularity : ellipseGeometry._granularity,
              vertexFormat : ellipseGeometry._vertexFormat,
              stRotation : ellipseGeometry._stRotation
          };
          var geometry;
          if (ellipseGeometry._extrude) {
              options.extrudedHeight = Math.min(ellipseGeometry._extrudedHeight, ellipseGeometry._height);
              options.height = Math.max(ellipseGeometry._extrudedHeight, ellipseGeometry._height);
              geometry = computeExtrudedEllipse(options);
          } else {
              geometry = computeEllipse(options);
          }
  
          return new Geometry({
              attributes : geometry.attributes,
              indices : geometry.indices,
              primitiveType : PrimitiveType.TRIANGLES,
              boundingSphere : geometry.boundingSphere
          });
      };
  
      return EllipseGeometry;
  });
  