jn_sis_zhfx/zhfx/Workers/GeometryPipeline-b4816e69.js

/* This file is automatically rebuilt by the Cesium build process. */
define(['exports', './AttributeCompression-4d18cc04', './Matrix2-fc7e9822', './RuntimeError-c581ca93', './defaultValue-94c3e563', './ComponentDatatype-4a60b8d6', './Transforms-a076dbe6', './EncodedCartesian3-d3e254ea', './GeometryAttribute-2ecf73f6', './IndexDatatype-db156785', './IntersectionTests-5deed78b', './Plane-e20fba8c'], (function (exports, AttributeCompression, Matrix2, RuntimeError, defaultValue, ComponentDatatype, Transforms, EncodedCartesian3, GeometryAttribute, IndexDatatype, IntersectionTests, Plane) { 'use strict';

  const scratchCartesian1 = new Matrix2.Cartesian3();
  const scratchCartesian2$1 = new Matrix2.Cartesian3();
  const scratchCartesian3$1 = new Matrix2.Cartesian3();

  /**
   * Computes the barycentric coordinates for a point with respect to a triangle.
   *
   * @function
   *
   * @param {Cartesian2|Cartesian3} point The point to test.
   * @param {Cartesian2|Cartesian3} p0 The first point of the triangle, corresponding to the barycentric x-axis.
   * @param {Cartesian2|Cartesian3} p1 The second point of the triangle, corresponding to the barycentric y-axis.
   * @param {Cartesian2|Cartesian3} p2 The third point of the triangle, corresponding to the barycentric z-axis.
   * @param {Cartesian3} [result] The object onto which to store the result.
   * @returns {Cartesian3|undefined} The modified result parameter or a new Cartesian3 instance if one was not provided. If the triangle is degenerate the function will return undefined.
   *
   * @example
   * // Returns Cartesian3.UNIT_X
   * const p = new Cesium.Cartesian3(-1.0, 0.0, 0.0);
   * const b = Cesium.barycentricCoordinates(p,
   *   new Cesium.Cartesian3(-1.0, 0.0, 0.0),
   *   new Cesium.Cartesian3( 1.0, 0.0, 0.0),
   *   new Cesium.Cartesian3( 0.0, 1.0, 1.0));
   */
  function barycentricCoordinates(point, p0, p1, p2, result) {
    //>>includeStart('debug', pragmas.debug);
    RuntimeError.Check.defined("point", point);
    RuntimeError.Check.defined("p0", p0);
    RuntimeError.Check.defined("p1", p1);
    RuntimeError.Check.defined("p2", p2);
    //>>includeEnd('debug');

    if (!defaultValue.defined(result)) {
      result = new Matrix2.Cartesian3();
    }

    // Implementation based on http://www.blackpawn.com/texts/pointinpoly/default.html.
    let v0;
    let v1;
    let v2;
    let dot00;
    let dot01;
    let dot02;
    let dot11;
    let dot12;

    if (!defaultValue.defined(p0.z)) {
      if (Matrix2.Cartesian2.equalsEpsilon(point, p0, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_X, result);
      }
      if (Matrix2.Cartesian2.equalsEpsilon(point, p1, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_Y, result);
      }
      if (Matrix2.Cartesian2.equalsEpsilon(point, p2, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_Z, result);
      }

      v0 = Matrix2.Cartesian2.subtract(p1, p0, scratchCartesian1);
      v1 = Matrix2.Cartesian2.subtract(p2, p0, scratchCartesian2$1);
      v2 = Matrix2.Cartesian2.subtract(point, p0, scratchCartesian3$1);

      dot00 = Matrix2.Cartesian2.dot(v0, v0);
      dot01 = Matrix2.Cartesian2.dot(v0, v1);
      dot02 = Matrix2.Cartesian2.dot(v0, v2);
      dot11 = Matrix2.Cartesian2.dot(v1, v1);
      dot12 = Matrix2.Cartesian2.dot(v1, v2);
    } else {
      if (Matrix2.Cartesian3.equalsEpsilon(point, p0, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_X, result);
      }
      if (Matrix2.Cartesian3.equalsEpsilon(point, p1, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_Y, result);
      }
      if (Matrix2.Cartesian3.equalsEpsilon(point, p2, ComponentDatatype.CesiumMath.EPSILON14)) {
        return Matrix2.Cartesian3.clone(Matrix2.Cartesian3.UNIT_Z, result);
      }

      v0 = Matrix2.Cartesian3.subtract(p1, p0, scratchCartesian1);
      v1 = Matrix2.Cartesian3.subtract(p2, p0, scratchCartesian2$1);
      v2 = Matrix2.Cartesian3.subtract(point, p0, scratchCartesian3$1);

      dot00 = Matrix2.Cartesian3.dot(v0, v0);
      dot01 = Matrix2.Cartesian3.dot(v0, v1);
      dot02 = Matrix2.Cartesian3.dot(v0, v2);
      dot11 = Matrix2.Cartesian3.dot(v1, v1);
      dot12 = Matrix2.Cartesian3.dot(v1, v2);
    }

    result.y = dot11 * dot02 - dot01 * dot12;
    result.z = dot00 * dot12 - dot01 * dot02;
    const q = dot00 * dot11 - dot01 * dot01;

    // Triangle is degenerate
    if (q === 0) {
      return undefined;
    }

    result.y /= q;
    result.z /= q;
    result.x = 1.0 - result.y - result.z;
    return result;
  }

  /**
   * Encapsulates an algorithm to optimize triangles for the post
   * vertex-shader cache.  This is based on the 2007 SIGGRAPH paper
   * 'Fast Triangle Reordering for Vertex Locality and Reduced Overdraw.'
   * The runtime is linear but several passes are made.
   *
   * @namespace Tipsify
   *
   * @see <a href='http://gfx.cs.princeton.edu/pubs/Sander_2007_%3ETR/tipsy.pdf'>
   * Fast Triangle Reordering for Vertex Locality and Reduced Overdraw</a>
   * by Sander, Nehab, and Barczak
   *
   * @private
   */
  const Tipsify = {};

  /**
   * Calculates the average cache miss ratio (ACMR) for a given set of indices.
   *
   * @param {Object} options Object with the following properties:
   * @param {Number[]} options.indices Lists triads of numbers corresponding to the indices of the vertices
   *                        in the vertex buffer that define the geometry's triangles.
   * @param {Number} [options.maximumIndex] The maximum value of the elements in <code>args.indices</code>.
   *                                     If not supplied, this value will be computed.
   * @param {Number} [options.cacheSize=24] The number of vertices that can be stored in the cache at any one time.
   * @returns {Number} The average cache miss ratio (ACMR).
   *
   * @exception {DeveloperError} indices length must be a multiple of three.
   * @exception {DeveloperError} cacheSize must be greater than two.
   *
   * @example
   * const indices = [0, 1, 2, 3, 4, 5];
   * const maxIndex = 5;
   * const cacheSize = 3;
   * const acmr = Cesium.Tipsify.calculateACMR({indices : indices, maxIndex : maxIndex, cacheSize : cacheSize});
   */
  Tipsify.calculateACMR = function (options) {
    options = defaultValue.defaultValue(options, defaultValue.defaultValue.EMPTY_OBJECT);
    const indices = options.indices;
    let maximumIndex = options.maximumIndex;
    const cacheSize = defaultValue.defaultValue(options.cacheSize, 24);

    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(indices)) {
      throw new RuntimeError.DeveloperError("indices is required.");
    }
    //>>includeEnd('debug');

    const numIndices = indices.length;

    //>>includeStart('debug', pragmas.debug);
    if (numIndices < 3 || numIndices % 3 !== 0) {
      throw new RuntimeError.DeveloperError("indices length must be a multiple of three.");
    }
    if (maximumIndex <= 0) {
      throw new RuntimeError.DeveloperError("maximumIndex must be greater than zero.");
    }
    if (cacheSize < 3) {
      throw new RuntimeError.DeveloperError("cacheSize must be greater than two.");
    }
    //>>includeEnd('debug');

    // Compute the maximumIndex if not given
    if (!defaultValue.defined(maximumIndex)) {
      maximumIndex = 0;
      let currentIndex = 0;
      let intoIndices = indices[currentIndex];
      while (currentIndex < numIndices) {
        if (intoIndices > maximumIndex) {
          maximumIndex = intoIndices;
        }
        ++currentIndex;
        intoIndices = indices[currentIndex];
      }
    }

    // Vertex time stamps
    const vertexTimeStamps = [];
    for (let i = 0; i < maximumIndex + 1; i++) {
      vertexTimeStamps[i] = 0;
    }

    // Cache processing
    let s = cacheSize + 1;
    for (let j = 0; j < numIndices; ++j) {
      if (s - vertexTimeStamps[indices[j]] > cacheSize) {
        vertexTimeStamps[indices[j]] = s;
        ++s;
      }
    }

    return (s - cacheSize + 1) / (numIndices / 3);
  };

  /**
   * Optimizes triangles for the post-vertex shader cache.
   *
   * @param {Object} options Object with the following properties:
   * @param {Number[]} options.indices Lists triads of numbers corresponding to the indices of the vertices
   *                        in the vertex buffer that define the geometry's triangles.
   * @param {Number} [options.maximumIndex] The maximum value of the elements in <code>args.indices</code>.
   *                                     If not supplied, this value will be computed.
   * @param {Number} [options.cacheSize=24] The number of vertices that can be stored in the cache at any one time.
   * @returns {Number[]} A list of the input indices in an optimized order.
   *
   * @exception {DeveloperError} indices length must be a multiple of three.
   * @exception {DeveloperError} cacheSize must be greater than two.
   *
   * @example
   * const indices = [0, 1, 2, 3, 4, 5];
   * const maxIndex = 5;
   * const cacheSize = 3;
   * const reorderedIndices = Cesium.Tipsify.tipsify({indices : indices, maxIndex : maxIndex, cacheSize : cacheSize});
   */
  Tipsify.tipsify = function (options) {
    options = defaultValue.defaultValue(options, defaultValue.defaultValue.EMPTY_OBJECT);
    const indices = options.indices;
    const maximumIndex = options.maximumIndex;
    const cacheSize = defaultValue.defaultValue(options.cacheSize, 24);

    let cursor;

    function skipDeadEnd(vertices, deadEnd, indices, maximumIndexPlusOne) {
      while (deadEnd.length >= 1) {
        // while the stack is not empty
        const d = deadEnd[deadEnd.length - 1]; // top of the stack
        deadEnd.splice(deadEnd.length - 1, 1); // pop the stack

        if (vertices[d].numLiveTriangles > 0) {
          return d;
        }
      }

      while (cursor < maximumIndexPlusOne) {
        if (vertices[cursor].numLiveTriangles > 0) {
          ++cursor;
          return cursor - 1;
        }
        ++cursor;
      }
      return -1;
    }

    function getNextVertex(
      indices,
      cacheSize,
      oneRing,
      vertices,
      s,
      deadEnd,
      maximumIndexPlusOne
    ) {
      let n = -1;
      let p;
      let m = -1;
      let itOneRing = 0;
      while (itOneRing < oneRing.length) {
        const index = oneRing[itOneRing];
        if (vertices[index].numLiveTriangles) {
          p = 0;
          if (
            s -
              vertices[index].timeStamp +
              2 * vertices[index].numLiveTriangles <=
            cacheSize
          ) {
            p = s - vertices[index].timeStamp;
          }
          if (p > m || m === -1) {
            m = p;
            n = index;
          }
        }
        ++itOneRing;
      }
      if (n === -1) {
        return skipDeadEnd(vertices, deadEnd, indices, maximumIndexPlusOne);
      }
      return n;
    }

    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(indices)) {
      throw new RuntimeError.DeveloperError("indices is required.");
    }
    //>>includeEnd('debug');

    const numIndices = indices.length;

    //>>includeStart('debug', pragmas.debug);
    if (numIndices < 3 || numIndices % 3 !== 0) {
      throw new RuntimeError.DeveloperError("indices length must be a multiple of three.");
    }
    if (maximumIndex <= 0) {
      throw new RuntimeError.DeveloperError("maximumIndex must be greater than zero.");
    }
    if (cacheSize < 3) {
      throw new RuntimeError.DeveloperError("cacheSize must be greater than two.");
    }
    //>>includeEnd('debug');

    // Determine maximum index
    let maximumIndexPlusOne = 0;
    let currentIndex = 0;
    let intoIndices = indices[currentIndex];
    const endIndex = numIndices;
    if (defaultValue.defined(maximumIndex)) {
      maximumIndexPlusOne = maximumIndex + 1;
    } else {
      while (currentIndex < endIndex) {
        if (intoIndices > maximumIndexPlusOne) {
          maximumIndexPlusOne = intoIndices;
        }
        ++currentIndex;
        intoIndices = indices[currentIndex];
      }
      if (maximumIndexPlusOne === -1) {
        return 0;
      }
      ++maximumIndexPlusOne;
    }

    // Vertices
    const vertices = [];
    let i;
    for (i = 0; i < maximumIndexPlusOne; i++) {
      vertices[i] = {
        numLiveTriangles: 0,
        timeStamp: 0,
        vertexTriangles: [],
      };
    }
    currentIndex = 0;
    let triangle = 0;
    while (currentIndex < endIndex) {
      vertices[indices[currentIndex]].vertexTriangles.push(triangle);
      ++vertices[indices[currentIndex]].numLiveTriangles;
      vertices[indices[currentIndex + 1]].vertexTriangles.push(triangle);
      ++vertices[indices[currentIndex + 1]].numLiveTriangles;
      vertices[indices[currentIndex + 2]].vertexTriangles.push(triangle);
      ++vertices[indices[currentIndex + 2]].numLiveTriangles;
      ++triangle;
      currentIndex += 3;
    }

    // Starting index
    let f = 0;

    // Time Stamp
    let s = cacheSize + 1;
    cursor = 1;

    // Process
    let oneRing = [];
    const deadEnd = []; //Stack
    let vertex;
    let intoVertices;
    let currentOutputIndex = 0;
    const outputIndices = [];
    const numTriangles = numIndices / 3;
    const triangleEmitted = [];
    for (i = 0; i < numTriangles; i++) {
      triangleEmitted[i] = false;
    }
    let index;
    let limit;
    while (f !== -1) {
      oneRing = [];
      intoVertices = vertices[f];
      limit = intoVertices.vertexTriangles.length;
      for (let k = 0; k < limit; ++k) {
        triangle = intoVertices.vertexTriangles[k];
        if (!triangleEmitted[triangle]) {
          triangleEmitted[triangle] = true;
          currentIndex = triangle + triangle + triangle;
          for (let j = 0; j < 3; ++j) {
            // Set this index as a possible next index
            index = indices[currentIndex];
            oneRing.push(index);
            deadEnd.push(index);

            // Output index
            outputIndices[currentOutputIndex] = index;
            ++currentOutputIndex;

            // Cache processing
            vertex = vertices[index];
            --vertex.numLiveTriangles;
            if (s - vertex.timeStamp > cacheSize) {
              vertex.timeStamp = s;
              ++s;
            }
            ++currentIndex;
          }
        }
      }
      f = getNextVertex(
        indices,
        cacheSize,
        oneRing,
        vertices,
        s,
        deadEnd,
        maximumIndexPlusOne
      );
    }

    return outputIndices;
  };

  /**
   * Content pipeline functions for geometries.
   *
   * @namespace GeometryPipeline
   *
   * @see Geometry
   */
  const GeometryPipeline = {};

  function addTriangle(lines, index, i0, i1, i2) {
    lines[index++] = i0;
    lines[index++] = i1;

    lines[index++] = i1;
    lines[index++] = i2;

    lines[index++] = i2;
    lines[index] = i0;
  }

  function trianglesToLines(triangles) {
    const count = triangles.length;
    const size = (count / 3) * 6;
    const lines = IndexDatatype.IndexDatatype.createTypedArray(count, size);

    let index = 0;
    for (let i = 0; i < count; i += 3, index += 6) {
      addTriangle(lines, index, triangles[i], triangles[i + 1], triangles[i + 2]);
    }

    return lines;
  }

  function triangleStripToLines(triangles) {
    const count = triangles.length;
    if (count >= 3) {
      const size = (count - 2) * 6;
      const lines = IndexDatatype.IndexDatatype.createTypedArray(count, size);

      addTriangle(lines, 0, triangles[0], triangles[1], triangles[2]);
      let index = 6;

      for (let i = 3; i < count; ++i, index += 6) {
        addTriangle(
          lines,
          index,
          triangles[i - 1],
          triangles[i],
          triangles[i - 2]
        );
      }

      return lines;
    }

    return new Uint16Array();
  }

  function triangleFanToLines(triangles) {
    if (triangles.length > 0) {
      const count = triangles.length - 1;
      const size = (count - 1) * 6;
      const lines = IndexDatatype.IndexDatatype.createTypedArray(count, size);

      const base = triangles[0];
      let index = 0;
      for (let i = 1; i < count; ++i, index += 6) {
        addTriangle(lines, index, base, triangles[i], triangles[i + 1]);
      }

      return lines;
    }

    return new Uint16Array();
  }

  /**
   * Converts a geometry's triangle indices to line indices.  If the geometry has an <code>indices</code>
   * and its <code>primitiveType</code> is <code>TRIANGLES</code>, <code>TRIANGLE_STRIP</code>,
   * <code>TRIANGLE_FAN</code>, it is converted to <code>LINES</code>; otherwise, the geometry is not changed.
   * <p>
   * This is commonly used to create a wireframe geometry for visual debugging.
   * </p>
   *
   * @param {Geometry} geometry The geometry to modify.
   * @returns {Geometry} The modified <code>geometry</code> argument, with its triangle indices converted to lines.
   *
   * @exception {DeveloperError} geometry.primitiveType must be TRIANGLES, TRIANGLE_STRIP, or TRIANGLE_FAN.
   *
   * @example
   * geometry = Cesium.GeometryPipeline.toWireframe(geometry);
   */
  GeometryPipeline.toWireframe = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug');

    const indices = geometry.indices;
    if (defaultValue.defined(indices)) {
      switch (geometry.primitiveType) {
        case GeometryAttribute.PrimitiveType.TRIANGLES:
          geometry.indices = trianglesToLines(indices);
          break;
        case GeometryAttribute.PrimitiveType.TRIANGLE_STRIP:
          geometry.indices = triangleStripToLines(indices);
          break;
        case GeometryAttribute.PrimitiveType.TRIANGLE_FAN:
          geometry.indices = triangleFanToLines(indices);
          break;
        //>>includeStart('debug', pragmas.debug);
        default:
          throw new RuntimeError.DeveloperError(
            "geometry.primitiveType must be TRIANGLES, TRIANGLE_STRIP, or TRIANGLE_FAN."
          );
        //>>includeEnd('debug');
      }

      geometry.primitiveType = GeometryAttribute.PrimitiveType.LINES;
    }

    return geometry;
  };

  /**
   * Creates a new {@link Geometry} with <code>LINES</code> representing the provided
   * attribute (<code>attributeName</code>) for the provided geometry.  This is used to
   * visualize vector attributes like normals, tangents, and bitangents.
   *
   * @param {Geometry} geometry The <code>Geometry</code> instance with the attribute.
   * @param {String} [attributeName='normal'] The name of the attribute.
   * @param {Number} [length=10000.0] The length of each line segment in meters.  This can be negative to point the vector in the opposite direction.
   * @returns {Geometry} A new <code>Geometry</code> instance with line segments for the vector.
   *
   * @exception {DeveloperError} geometry.attributes must have an attribute with the same name as the attributeName parameter.
   *
   * @example
   * const geometry = Cesium.GeometryPipeline.createLineSegmentsForVectors(instance.geometry, 'bitangent', 100000.0);
   */
  GeometryPipeline.createLineSegmentsForVectors = function (
    geometry,
    attributeName,
    length
  ) {
    attributeName = defaultValue.defaultValue(attributeName, "normal");

    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    if (!defaultValue.defined(geometry.attributes.position)) {
      throw new RuntimeError.DeveloperError("geometry.attributes.position is required.");
    }
    if (!defaultValue.defined(geometry.attributes[attributeName])) {
      throw new RuntimeError.DeveloperError(
        `geometry.attributes must have an attribute with the same name as the attributeName parameter, ${attributeName}.`
      );
    }
    //>>includeEnd('debug');

    length = defaultValue.defaultValue(length, 10000.0);

    const positions = geometry.attributes.position.values;
    const vectors = geometry.attributes[attributeName].values;
    const positionsLength = positions.length;

    const newPositions = new Float64Array(2 * positionsLength);

    let j = 0;
    for (let i = 0; i < positionsLength; i += 3) {
      newPositions[j++] = positions[i];
      newPositions[j++] = positions[i + 1];
      newPositions[j++] = positions[i + 2];

      newPositions[j++] = positions[i] + vectors[i] * length;
      newPositions[j++] = positions[i + 1] + vectors[i + 1] * length;
      newPositions[j++] = positions[i + 2] + vectors[i + 2] * length;
    }

    let newBoundingSphere;
    const bs = geometry.boundingSphere;
    if (defaultValue.defined(bs)) {
      newBoundingSphere = new Transforms.BoundingSphere(bs.center, bs.radius + length);
    }

    return new GeometryAttribute.Geometry({
      attributes: {
        position: new GeometryAttribute.GeometryAttribute({
          componentDatatype: ComponentDatatype.ComponentDatatype.DOUBLE,
          componentsPerAttribute: 3,
          values: newPositions,
        }),
      },
      primitiveType: GeometryAttribute.PrimitiveType.LINES,
      boundingSphere: newBoundingSphere,
    });
  };

  /**
   * Creates an object that maps attribute names to unique locations (indices)
   * for matching vertex attributes and shader programs.
   *
   * @param {Geometry} geometry The geometry, which is not modified, to create the object for.
   * @returns {Object} An object with attribute name / index pairs.
   *
   * @example
   * const attributeLocations = Cesium.GeometryPipeline.createAttributeLocations(geometry);
   * // Example output
   * // {
   * //   'position' : 0,
   * //   'normal' : 1
   * // }
   */
  GeometryPipeline.createAttributeLocations = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug')

    // There can be a WebGL performance hit when attribute 0 is disabled, so
    // assign attribute locations to well-known attributes.
    const semantics = [
      "position",
      "positionHigh",
      "positionLow",

      // From VertexFormat.position - after 2D projection and high-precision encoding
      "position3DHigh",
      "position3DLow",
      "position2DHigh",
      "position2DLow",

      // From Primitive
      "pickColor",

      // From VertexFormat
      "normal",
      "st",
      "tangent",
      "bitangent",

      // For shadow volumes
      "extrudeDirection",

      // From compressing texture coordinates and normals
      "compressedAttributes",
    ];

    const attributes = geometry.attributes;
    const indices = {};
    let j = 0;
    let i;
    const len = semantics.length;

    // Attribute locations for well-known attributes
    for (i = 0; i < len; ++i) {
      const semantic = semantics[i];

      if (defaultValue.defined(attributes[semantic])) {
        indices[semantic] = j++;
      }
    }

    // Locations for custom attributes
    for (const name in attributes) {
      if (attributes.hasOwnProperty(name) && !defaultValue.defined(indices[name])) {
        indices[name] = j++;
      }
    }

    return indices;
  };

  /**
   * Reorders a geometry's attributes and <code>indices</code> to achieve better performance from the GPU's pre-vertex-shader cache.
   *
   * @param {Geometry} geometry The geometry to modify.
   * @returns {Geometry} The modified <code>geometry</code> argument, with its attributes and indices reordered for the GPU's pre-vertex-shader cache.
   *
   * @exception {DeveloperError} Each attribute array in geometry.attributes must have the same number of attributes.
   *
   *
   * @example
   * geometry = Cesium.GeometryPipeline.reorderForPreVertexCache(geometry);
   *
   * @see GeometryPipeline.reorderForPostVertexCache
   */
  GeometryPipeline.reorderForPreVertexCache = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug');

    const numVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    const indices = geometry.indices;
    if (defaultValue.defined(indices)) {
      const indexCrossReferenceOldToNew = new Int32Array(numVertices);
      for (let i = 0; i < numVertices; i++) {
        indexCrossReferenceOldToNew[i] = -1;
      }

      // Construct cross reference and reorder indices
      const indicesIn = indices;
      const numIndices = indicesIn.length;
      const indicesOut = IndexDatatype.IndexDatatype.createTypedArray(numVertices, numIndices);

      let intoIndicesIn = 0;
      let intoIndicesOut = 0;
      let nextIndex = 0;
      let tempIndex;
      while (intoIndicesIn < numIndices) {
        tempIndex = indexCrossReferenceOldToNew[indicesIn[intoIndicesIn]];
        if (tempIndex !== -1) {
          indicesOut[intoIndicesOut] = tempIndex;
        } else {
          tempIndex = indicesIn[intoIndicesIn];
          indexCrossReferenceOldToNew[tempIndex] = nextIndex;

          indicesOut[intoIndicesOut] = nextIndex;
          ++nextIndex;
        }
        ++intoIndicesIn;
        ++intoIndicesOut;
      }
      geometry.indices = indicesOut;

      // Reorder attributes
      const attributes = geometry.attributes;
      for (const property in attributes) {
        if (
          attributes.hasOwnProperty(property) &&
          defaultValue.defined(attributes[property]) &&
          defaultValue.defined(attributes[property].values)
        ) {
          const attribute = attributes[property];
          const elementsIn = attribute.values;
          let intoElementsIn = 0;
          const numComponents = attribute.componentsPerAttribute;
          const elementsOut = ComponentDatatype.ComponentDatatype.createTypedArray(
            attribute.componentDatatype,
            nextIndex * numComponents
          );
          while (intoElementsIn < numVertices) {
            const temp = indexCrossReferenceOldToNew[intoElementsIn];
            if (temp !== -1) {
              for (let j = 0; j < numComponents; j++) {
                elementsOut[numComponents * temp + j] =
                  elementsIn[numComponents * intoElementsIn + j];
              }
            }
            ++intoElementsIn;
          }
          attribute.values = elementsOut;
        }
      }
    }

    return geometry;
  };

  /**
   * Reorders a geometry's <code>indices</code> to achieve better performance from the GPU's
   * post vertex-shader cache by using the Tipsify algorithm.  If the geometry <code>primitiveType</code>
   * is not <code>TRIANGLES</code> or the geometry does not have an <code>indices</code>, this function has no effect.
   *
   * @param {Geometry} geometry The geometry to modify.
   * @param {Number} [cacheCapacity=24] The number of vertices that can be held in the GPU's vertex cache.
   * @returns {Geometry} The modified <code>geometry</code> argument, with its indices reordered for the post-vertex-shader cache.
   *
   * @exception {DeveloperError} cacheCapacity must be greater than two.
   *
   *
   * @example
   * geometry = Cesium.GeometryPipeline.reorderForPostVertexCache(geometry);
   *
   * @see GeometryPipeline.reorderForPreVertexCache
   * @see {@link http://gfx.cs.princ0eton.edu/pubs/Sander_2007_%3ETR/tipsy.pdf|Fast Triangle Reordering for Vertex Locality and Reduced Overdraw}
   * by Sander, Nehab, and Barczak
   */
  GeometryPipeline.reorderForPostVertexCache = function (
    geometry,
    cacheCapacity
  ) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug');

    const indices = geometry.indices;
    if (geometry.primitiveType === GeometryAttribute.PrimitiveType.TRIANGLES && defaultValue.defined(indices)) {
      const numIndices = indices.length;
      let maximumIndex = 0;
      for (let j = 0; j < numIndices; j++) {
        if (indices[j] > maximumIndex) {
          maximumIndex = indices[j];
        }
      }
      geometry.indices = Tipsify.tipsify({
        indices: indices,
        maximumIndex: maximumIndex,
        cacheSize: cacheCapacity,
      });
    }

    return geometry;
  };

  function copyAttributesDescriptions(attributes) {
    const newAttributes = {};

    for (const attribute in attributes) {
      if (
        attributes.hasOwnProperty(attribute) &&
        defaultValue.defined(attributes[attribute]) &&
        defaultValue.defined(attributes[attribute].values)
      ) {
        const attr = attributes[attribute];
        newAttributes[attribute] = new GeometryAttribute.GeometryAttribute({
          componentDatatype: attr.componentDatatype,
          componentsPerAttribute: attr.componentsPerAttribute,
          normalize: attr.normalize,
          values: [],
        });
      }
    }

    return newAttributes;
  }

  function copyVertex(destinationAttributes, sourceAttributes, index) {
    for (const attribute in sourceAttributes) {
      if (
        sourceAttributes.hasOwnProperty(attribute) &&
        defaultValue.defined(sourceAttributes[attribute]) &&
        defaultValue.defined(sourceAttributes[attribute].values)
      ) {
        const attr = sourceAttributes[attribute];

        for (let k = 0; k < attr.componentsPerAttribute; ++k) {
          destinationAttributes[attribute].values.push(
            attr.values[index * attr.componentsPerAttribute + k]
          );
        }
      }
    }
  }

  /**
   * Splits a geometry into multiple geometries, if necessary, to ensure that indices in the
   * <code>indices</code> fit into unsigned shorts.  This is used to meet the WebGL requirements
   * when unsigned int indices are not supported.
   * <p>
   * If the geometry does not have any <code>indices</code>, this function has no effect.
   * </p>
   *
   * @param {Geometry} geometry The geometry to be split into multiple geometries.
   * @returns {Geometry[]} An array of geometries, each with indices that fit into unsigned shorts.
   *
   * @exception {DeveloperError} geometry.primitiveType must equal to PrimitiveType.TRIANGLES, PrimitiveType.LINES, or PrimitiveType.POINTS
   * @exception {DeveloperError} All geometry attribute lists must have the same number of attributes.
   *
   * @example
   * const geometries = Cesium.GeometryPipeline.fitToUnsignedShortIndices(geometry);
   */
  GeometryPipeline.fitToUnsignedShortIndices = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    if (
      defaultValue.defined(geometry.indices) &&
      geometry.primitiveType !== GeometryAttribute.PrimitiveType.TRIANGLES &&
      geometry.primitiveType !== GeometryAttribute.PrimitiveType.LINES &&
      geometry.primitiveType !== GeometryAttribute.PrimitiveType.POINTS
    ) {
      throw new RuntimeError.DeveloperError(
        "geometry.primitiveType must equal to PrimitiveType.TRIANGLES, PrimitiveType.LINES, or PrimitiveType.POINTS."
      );
    }
    //>>includeEnd('debug');

    const geometries = [];

    // If there's an index list and more than 64K attributes, it is possible that
    // some indices are outside the range of unsigned short [0, 64K - 1]
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);
    if (
      defaultValue.defined(geometry.indices) &&
      numberOfVertices >= ComponentDatatype.CesiumMath.SIXTY_FOUR_KILOBYTES
    ) {
      let oldToNewIndex = [];
      let newIndices = [];
      let currentIndex = 0;
      let newAttributes = copyAttributesDescriptions(geometry.attributes);

      const originalIndices = geometry.indices;
      const numberOfIndices = originalIndices.length;

      let indicesPerPrimitive;

      if (geometry.primitiveType === GeometryAttribute.PrimitiveType.TRIANGLES) {
        indicesPerPrimitive = 3;
      } else if (geometry.primitiveType === GeometryAttribute.PrimitiveType.LINES) {
        indicesPerPrimitive = 2;
      } else if (geometry.primitiveType === GeometryAttribute.PrimitiveType.POINTS) {
        indicesPerPrimitive = 1;
      }

      for (let j = 0; j < numberOfIndices; j += indicesPerPrimitive) {
        for (let k = 0; k < indicesPerPrimitive; ++k) {
          const x = originalIndices[j + k];
          let i = oldToNewIndex[x];
          if (!defaultValue.defined(i)) {
            i = currentIndex++;
            oldToNewIndex[x] = i;
            copyVertex(newAttributes, geometry.attributes, x);
          }
          newIndices.push(i);
        }

        if (
          currentIndex + indicesPerPrimitive >=
          ComponentDatatype.CesiumMath.SIXTY_FOUR_KILOBYTES
        ) {
          geometries.push(
            new GeometryAttribute.Geometry({
              attributes: newAttributes,
              indices: newIndices,
              primitiveType: geometry.primitiveType,
              boundingSphere: geometry.boundingSphere,
              boundingSphereCV: geometry.boundingSphereCV,
            })
          );

          // Reset for next vertex-array
          oldToNewIndex = [];
          newIndices = [];
          currentIndex = 0;
          newAttributes = copyAttributesDescriptions(geometry.attributes);
        }
      }

      if (newIndices.length !== 0) {
        geometries.push(
          new GeometryAttribute.Geometry({
            attributes: newAttributes,
            indices: newIndices,
            primitiveType: geometry.primitiveType,
            boundingSphere: geometry.boundingSphere,
            boundingSphereCV: geometry.boundingSphereCV,
          })
        );
      }
    } else {
      // No need to split into multiple geometries
      geometries.push(geometry);
    }

    return geometries;
  };

  const scratchProjectTo2DCartesian3 = new Matrix2.Cartesian3();
  const scratchProjectTo2DCartographic = new Matrix2.Cartographic();

  /**
   * Projects a geometry's 3D <code>position</code> attribute to 2D, replacing the <code>position</code>
   * attribute with separate <code>position3D</code> and <code>position2D</code> attributes.
   * <p>
   * If the geometry does not have a <code>position</code>, this function has no effect.
   * </p>
   *
   * @param {Geometry} geometry The geometry to modify.
   * @param {String} attributeName The name of the attribute.
   * @param {String} attributeName3D The name of the attribute in 3D.
   * @param {String} attributeName2D The name of the attribute in 2D.
   * @param {Object} [projection=new GeographicProjection()] The projection to use.
   * @returns {Geometry} The modified <code>geometry</code> argument with <code>position3D</code> and <code>position2D</code> attributes.
   *
   * @exception {DeveloperError} geometry must have attribute matching the attributeName argument.
   * @exception {DeveloperError} The attribute componentDatatype must be ComponentDatatype.DOUBLE.
   * @exception {DeveloperError} Could not project a point to 2D.
   *
   * @example
   * geometry = Cesium.GeometryPipeline.projectTo2D(geometry, 'position', 'position3D', 'position2D');
   */
  GeometryPipeline.projectTo2D = function (
    geometry,
    attributeName,
    attributeName3D,
    attributeName2D,
    projection
  ) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    if (!defaultValue.defined(attributeName)) {
      throw new RuntimeError.DeveloperError("attributeName is required.");
    }
    if (!defaultValue.defined(attributeName3D)) {
      throw new RuntimeError.DeveloperError("attributeName3D is required.");
    }
    if (!defaultValue.defined(attributeName2D)) {
      throw new RuntimeError.DeveloperError("attributeName2D is required.");
    }
    if (!defaultValue.defined(geometry.attributes[attributeName])) {
      throw new RuntimeError.DeveloperError(
        `geometry must have attribute matching the attributeName argument: ${attributeName}.`
      );
    }
    if (
      geometry.attributes[attributeName].componentDatatype !==
      ComponentDatatype.ComponentDatatype.DOUBLE
    ) {
      throw new RuntimeError.DeveloperError(
        "The attribute componentDatatype must be ComponentDatatype.DOUBLE."
      );
    }
    //>>includeEnd('debug');

    const attribute = geometry.attributes[attributeName];
    projection = defaultValue.defined(projection) ? projection : new Transforms.GeographicProjection();
    const ellipsoid = projection.ellipsoid;

    // Project original values to 2D.
    const values3D = attribute.values;
    const projectedValues = new Float64Array(values3D.length);
    let index = 0;

    for (let i = 0; i < values3D.length; i += 3) {
      const value = Matrix2.Cartesian3.fromArray(
        values3D,
        i,
        scratchProjectTo2DCartesian3
      );

      const lonLat = ellipsoid.cartesianToCartographic(
        value,
        scratchProjectTo2DCartographic
      );
      //>>includeStart('debug', pragmas.debug);
      if (!defaultValue.defined(lonLat)) {
        throw new RuntimeError.DeveloperError(
          `Could not project point (${value.x}, ${value.y}, ${value.z}) to 2D.`
        );
      }
      //>>includeEnd('debug');

      const projectedLonLat = projection.project(
        lonLat,
        scratchProjectTo2DCartesian3
      );

      projectedValues[index++] = projectedLonLat.x;
      projectedValues[index++] = projectedLonLat.y;
      projectedValues[index++] = projectedLonLat.z;
    }

    // Rename original cartesians to WGS84 cartesians.
    geometry.attributes[attributeName3D] = attribute;

    // Replace original cartesians with 2D projected cartesians
    geometry.attributes[attributeName2D] = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.DOUBLE,
      componentsPerAttribute: 3,
      values: projectedValues,
    });
    delete geometry.attributes[attributeName];

    return geometry;
  };

  const encodedResult = {
    high: 0.0,
    low: 0.0,
  };

  /**
   * Encodes floating-point geometry attribute values as two separate attributes to improve
   * rendering precision.
   * <p>
   * This is commonly used to create high-precision position vertex attributes.
   * </p>
   *
   * @param {Geometry} geometry The geometry to modify.
   * @param {String} attributeName The name of the attribute.
   * @param {String} attributeHighName The name of the attribute for the encoded high bits.
   * @param {String} attributeLowName The name of the attribute for the encoded low bits.
   * @returns {Geometry} The modified <code>geometry</code> argument, with its encoded attribute.
   *
   * @exception {DeveloperError} geometry must have attribute matching the attributeName argument.
   * @exception {DeveloperError} The attribute componentDatatype must be ComponentDatatype.DOUBLE.
   *
   * @example
   * geometry = Cesium.GeometryPipeline.encodeAttribute(geometry, 'position3D', 'position3DHigh', 'position3DLow');
   */
  GeometryPipeline.encodeAttribute = function (
    geometry,
    attributeName,
    attributeHighName,
    attributeLowName
  ) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    if (!defaultValue.defined(attributeName)) {
      throw new RuntimeError.DeveloperError("attributeName is required.");
    }
    if (!defaultValue.defined(attributeHighName)) {
      throw new RuntimeError.DeveloperError("attributeHighName is required.");
    }
    if (!defaultValue.defined(attributeLowName)) {
      throw new RuntimeError.DeveloperError("attributeLowName is required.");
    }
    if (!defaultValue.defined(geometry.attributes[attributeName])) {
      throw new RuntimeError.DeveloperError(
        `geometry must have attribute matching the attributeName argument: ${attributeName}.`
      );
    }
    if (
      geometry.attributes[attributeName].componentDatatype !==
      ComponentDatatype.ComponentDatatype.DOUBLE
    ) {
      throw new RuntimeError.DeveloperError(
        "The attribute componentDatatype must be ComponentDatatype.DOUBLE."
      );
    }
    //>>includeEnd('debug');

    const attribute = geometry.attributes[attributeName];
    const values = attribute.values;
    const length = values.length;
    const highValues = new Float32Array(length);
    const lowValues = new Float32Array(length);

    for (let i = 0; i < length; ++i) {
      EncodedCartesian3.EncodedCartesian3.encode(values[i], encodedResult);
      highValues[i] = encodedResult.high;
      lowValues[i] = encodedResult.low;
    }

    const componentsPerAttribute = attribute.componentsPerAttribute;

    geometry.attributes[attributeHighName] = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: componentsPerAttribute,
      values: highValues,
    });
    geometry.attributes[attributeLowName] = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: componentsPerAttribute,
      values: lowValues,
    });
    delete geometry.attributes[attributeName];

    return geometry;
  };

  let scratchCartesian3 = new Matrix2.Cartesian3();

  function transformPoint(matrix, attribute) {
    if (defaultValue.defined(attribute)) {
      const values = attribute.values;
      const length = values.length;
      for (let i = 0; i < length; i += 3) {
        Matrix2.Cartesian3.unpack(values, i, scratchCartesian3);
        Matrix2.Matrix4.multiplyByPoint(matrix, scratchCartesian3, scratchCartesian3);
        Matrix2.Cartesian3.pack(scratchCartesian3, values, i);
      }
    }
  }

  function transformVector(matrix, attribute) {
    if (defaultValue.defined(attribute)) {
      const values = attribute.values;
      const length = values.length;
      for (let i = 0; i < length; i += 3) {
        Matrix2.Cartesian3.unpack(values, i, scratchCartesian3);
        Matrix2.Matrix3.multiplyByVector(matrix, scratchCartesian3, scratchCartesian3);
        scratchCartesian3 = Matrix2.Cartesian3.normalize(
          scratchCartesian3,
          scratchCartesian3
        );
        Matrix2.Cartesian3.pack(scratchCartesian3, values, i);
      }
    }
  }

  const inverseTranspose = new Matrix2.Matrix4();
  const normalMatrix = new Matrix2.Matrix3();

  /**
   * Transforms a geometry instance to world coordinates.  This changes
   * the instance's <code>modelMatrix</code> to {@link Matrix4.IDENTITY} and transforms the
   * following attributes if they are present: <code>position</code>, <code>normal</code>,
   * <code>tangent</code>, and <code>bitangent</code>.
   *
   * @param {GeometryInstance} instance The geometry instance to modify.
   * @returns {GeometryInstance} The modified <code>instance</code> argument, with its attributes transforms to world coordinates.
   *
   * @example
   * Cesium.GeometryPipeline.transformToWorldCoordinates(instance);
   */
  GeometryPipeline.transformToWorldCoordinates = function (instance) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(instance)) {
      throw new RuntimeError.DeveloperError("instance is required.");
    }
    //>>includeEnd('debug');

    const modelMatrix = instance.modelMatrix;

    if (Matrix2.Matrix4.equals(modelMatrix, Matrix2.Matrix4.IDENTITY)) {
      // Already in world coordinates
      return instance;
    }

    const attributes = instance.geometry.attributes;

    // Transform attributes in known vertex formats
    transformPoint(modelMatrix, attributes.position);
    transformPoint(modelMatrix, attributes.prevPosition);
    transformPoint(modelMatrix, attributes.nextPosition);

    if (
      defaultValue.defined(attributes.normal) ||
      defaultValue.defined(attributes.tangent) ||
      defaultValue.defined(attributes.bitangent)
    ) {
      Matrix2.Matrix4.inverse(modelMatrix, inverseTranspose);
      Matrix2.Matrix4.transpose(inverseTranspose, inverseTranspose);
      Matrix2.Matrix4.getMatrix3(inverseTranspose, normalMatrix);

      transformVector(normalMatrix, attributes.normal);
      transformVector(normalMatrix, attributes.tangent);
      transformVector(normalMatrix, attributes.bitangent);
    }

    const boundingSphere = instance.geometry.boundingSphere;
    if (defaultValue.defined(boundingSphere)) {
      instance.geometry.boundingSphere = Transforms.BoundingSphere.transform(
        boundingSphere,
        modelMatrix,
        boundingSphere
      );
    }

    instance.modelMatrix = Matrix2.Matrix4.clone(Matrix2.Matrix4.IDENTITY);

    return instance;
  };

  function findAttributesInAllGeometries(instances, propertyName) {
    const length = instances.length;

    const attributesInAllGeometries = {};

    const attributes0 = instances[0][propertyName].attributes;
    let name;

    for (name in attributes0) {
      if (
        attributes0.hasOwnProperty(name) &&
        defaultValue.defined(attributes0[name]) &&
        defaultValue.defined(attributes0[name].values)
      ) {
        const attribute = attributes0[name];
        let numberOfComponents = attribute.values.length;
        let inAllGeometries = true;

        // Does this same attribute exist in all geometries?
        for (let i = 1; i < length; ++i) {
          const otherAttribute = instances[i][propertyName].attributes[name];

          if (
            !defaultValue.defined(otherAttribute) ||
            attribute.componentDatatype !== otherAttribute.componentDatatype ||
            attribute.componentsPerAttribute !==
              otherAttribute.componentsPerAttribute ||
            attribute.normalize !== otherAttribute.normalize
          ) {
            inAllGeometries = false;
            break;
          }

          numberOfComponents += otherAttribute.values.length;
        }

        if (inAllGeometries) {
          attributesInAllGeometries[name] = new GeometryAttribute.GeometryAttribute({
            componentDatatype: attribute.componentDatatype,
            componentsPerAttribute: attribute.componentsPerAttribute,
            normalize: attribute.normalize,
            values: ComponentDatatype.ComponentDatatype.createTypedArray(
              attribute.componentDatatype,
              numberOfComponents
            ),
          });
        }
      }
    }

    return attributesInAllGeometries;
  }

  const tempScratch = new Matrix2.Cartesian3();

  function combineGeometries(instances, propertyName) {
    const length = instances.length;

    let name;
    let i;
    let j;
    let k;

    const m = instances[0].modelMatrix;
    const haveIndices = defaultValue.defined(instances[0][propertyName].indices);
    const primitiveType = instances[0][propertyName].primitiveType;

    //>>includeStart('debug', pragmas.debug);
    for (i = 1; i < length; ++i) {
      if (!Matrix2.Matrix4.equals(instances[i].modelMatrix, m)) {
        throw new RuntimeError.DeveloperError("All instances must have the same modelMatrix.");
      }
      if (defaultValue.defined(instances[i][propertyName].indices) !== haveIndices) {
        throw new RuntimeError.DeveloperError(
          "All instance geometries must have an indices or not have one."
        );
      }
      if (instances[i][propertyName].primitiveType !== primitiveType) {
        throw new RuntimeError.DeveloperError(
          "All instance geometries must have the same primitiveType."
        );
      }
    }
    //>>includeEnd('debug');

    // Find subset of attributes in all geometries
    const attributes = findAttributesInAllGeometries(instances, propertyName);
    let values;
    let sourceValues;
    let sourceValuesLength;

    // Combine attributes from each geometry into a single typed array
    for (name in attributes) {
      if (attributes.hasOwnProperty(name)) {
        values = attributes[name].values;

        k = 0;
        for (i = 0; i < length; ++i) {
          sourceValues = instances[i][propertyName].attributes[name].values;
          sourceValuesLength = sourceValues.length;

          for (j = 0; j < sourceValuesLength; ++j) {
            values[k++] = sourceValues[j];
          }
        }
      }
    }

    // Combine index lists
    let indices;

    if (haveIndices) {
      let numberOfIndices = 0;
      for (i = 0; i < length; ++i) {
        numberOfIndices += instances[i][propertyName].indices.length;
      }

      const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(
        new GeometryAttribute.Geometry({
          attributes: attributes,
          primitiveType: GeometryAttribute.PrimitiveType.POINTS,
        })
      );
      const destIndices = IndexDatatype.IndexDatatype.createTypedArray(
        numberOfVertices,
        numberOfIndices
      );

      let destOffset = 0;
      let offset = 0;

      for (i = 0; i < length; ++i) {
        const sourceIndices = instances[i][propertyName].indices;
        const sourceIndicesLen = sourceIndices.length;

        for (k = 0; k < sourceIndicesLen; ++k) {
          destIndices[destOffset++] = offset + sourceIndices[k];
        }

        offset += GeometryAttribute.Geometry.computeNumberOfVertices(instances[i][propertyName]);
      }

      indices = destIndices;
    }

    // Create bounding sphere that includes all instances
    let center = new Matrix2.Cartesian3();
    let radius = 0.0;
    let bs;

    for (i = 0; i < length; ++i) {
      bs = instances[i][propertyName].boundingSphere;
      if (!defaultValue.defined(bs)) {
        // If any geometries have an undefined bounding sphere, then so does the combined geometry
        center = undefined;
        break;
      }

      Matrix2.Cartesian3.add(bs.center, center, center);
    }

    if (defaultValue.defined(center)) {
      Matrix2.Cartesian3.divideByScalar(center, length, center);

      for (i = 0; i < length; ++i) {
        bs = instances[i][propertyName].boundingSphere;
        const tempRadius =
          Matrix2.Cartesian3.magnitude(
            Matrix2.Cartesian3.subtract(bs.center, center, tempScratch)
          ) + bs.radius;

        if (tempRadius > radius) {
          radius = tempRadius;
        }
      }
    }

    return new GeometryAttribute.Geometry({
      attributes: attributes,
      indices: indices,
      primitiveType: primitiveType,
      boundingSphere: defaultValue.defined(center)
        ? new Transforms.BoundingSphere(center, radius)
        : undefined,
    });
  }

  /**
   * Combines geometry from several {@link GeometryInstance} objects into one geometry.
   * This concatenates the attributes, concatenates and adjusts the indices, and creates
   * a bounding sphere encompassing all instances.
   * <p>
   * If the instances do not have the same attributes, a subset of attributes common
   * to all instances is used, and the others are ignored.
   * </p>
   * <p>
   * This is used by {@link Primitive} to efficiently render a large amount of static data.
   * </p>
   *
   * @private
   *
   * @param {GeometryInstance[]} [instances] The array of {@link GeometryInstance} objects whose geometry will be combined.
   * @returns {Geometry} A single geometry created from the provided geometry instances.
   *
   * @exception {DeveloperError} All instances must have the same modelMatrix.
   * @exception {DeveloperError} All instance geometries must have an indices or not have one.
   * @exception {DeveloperError} All instance geometries must have the same primitiveType.
   *
   *
   * @example
   * for (let i = 0; i < instances.length; ++i) {
   *   Cesium.GeometryPipeline.transformToWorldCoordinates(instances[i]);
   * }
   * const geometries = Cesium.GeometryPipeline.combineInstances(instances);
   *
   * @see GeometryPipeline.transformToWorldCoordinates
   */
  GeometryPipeline.combineInstances = function (instances) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(instances) || instances.length < 1) {
      throw new RuntimeError.DeveloperError(
        "instances is required and must have length greater than zero."
      );
    }
    //>>includeEnd('debug');

    const instanceGeometry = [];
    const instanceSplitGeometry = [];
    const length = instances.length;
    for (let i = 0; i < length; ++i) {
      const instance = instances[i];

      if (defaultValue.defined(instance.geometry)) {
        instanceGeometry.push(instance);
      } else if (
        defaultValue.defined(instance.westHemisphereGeometry) &&
        defaultValue.defined(instance.eastHemisphereGeometry)
      ) {
        instanceSplitGeometry.push(instance);
      }
    }

    const geometries = [];
    if (instanceGeometry.length > 0) {
      geometries.push(combineGeometries(instanceGeometry, "geometry"));
    }

    if (instanceSplitGeometry.length > 0) {
      geometries.push(
        combineGeometries(instanceSplitGeometry, "westHemisphereGeometry")
      );
      geometries.push(
        combineGeometries(instanceSplitGeometry, "eastHemisphereGeometry")
      );
    }

    return geometries;
  };

  const normal = new Matrix2.Cartesian3();
  const v0 = new Matrix2.Cartesian3();
  const v1 = new Matrix2.Cartesian3();
  const v2 = new Matrix2.Cartesian3();

  /**
   * Computes per-vertex normals for a geometry containing <code>TRIANGLES</code> by averaging the normals of
   * all triangles incident to the vertex.  The result is a new <code>normal</code> attribute added to the geometry.
   * This assumes a counter-clockwise winding order.
   *
   * @param {Geometry} geometry The geometry to modify.
   * @returns {Geometry} The modified <code>geometry</code> argument with the computed <code>normal</code> attribute.
   *
   * @exception {DeveloperError} geometry.indices length must be greater than 0 and be a multiple of 3.
   * @exception {DeveloperError} geometry.primitiveType must be {@link PrimitiveType.TRIANGLES}.
   *
   * @example
   * Cesium.GeometryPipeline.computeNormal(geometry);
   */
  GeometryPipeline.computeNormal = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    if (
      !defaultValue.defined(geometry.attributes.position) ||
      !defaultValue.defined(geometry.attributes.position.values)
    ) {
      throw new RuntimeError.DeveloperError(
        "geometry.attributes.position.values is required."
      );
    }
    if (!defaultValue.defined(geometry.indices)) {
      throw new RuntimeError.DeveloperError("geometry.indices is required.");
    }
    if (geometry.indices.length < 2 || geometry.indices.length % 3 !== 0) {
      throw new RuntimeError.DeveloperError(
        "geometry.indices length must be greater than 0 and be a multiple of 3."
      );
    }
    if (geometry.primitiveType !== GeometryAttribute.PrimitiveType.TRIANGLES) {
      throw new RuntimeError.DeveloperError(
        "geometry.primitiveType must be PrimitiveType.TRIANGLES."
      );
    }
    //>>includeEnd('debug');

    const indices = geometry.indices;
    const attributes = geometry.attributes;
    const vertices = attributes.position.values;
    const numVertices = attributes.position.values.length / 3;
    const numIndices = indices.length;
    const normalsPerVertex = new Array(numVertices);
    const normalsPerTriangle = new Array(numIndices / 3);
    const normalIndices = new Array(numIndices);
    let i;
    for (i = 0; i < numVertices; i++) {
      normalsPerVertex[i] = {
        indexOffset: 0,
        count: 0,
        currentCount: 0,
      };
    }

    let j = 0;
    for (i = 0; i < numIndices; i += 3) {
      const i0 = indices[i];
      const i1 = indices[i + 1];
      const i2 = indices[i + 2];
      const i03 = i0 * 3;
      const i13 = i1 * 3;
      const i23 = i2 * 3;

      v0.x = vertices[i03];
      v0.y = vertices[i03 + 1];
      v0.z = vertices[i03 + 2];
      v1.x = vertices[i13];
      v1.y = vertices[i13 + 1];
      v1.z = vertices[i13 + 2];
      v2.x = vertices[i23];
      v2.y = vertices[i23 + 1];
      v2.z = vertices[i23 + 2];

      normalsPerVertex[i0].count++;
      normalsPerVertex[i1].count++;
      normalsPerVertex[i2].count++;

      Matrix2.Cartesian3.subtract(v1, v0, v1);
      Matrix2.Cartesian3.subtract(v2, v0, v2);
      normalsPerTriangle[j] = Matrix2.Cartesian3.cross(v1, v2, new Matrix2.Cartesian3());
      j++;
    }

    let indexOffset = 0;
    for (i = 0; i < numVertices; i++) {
      normalsPerVertex[i].indexOffset += indexOffset;
      indexOffset += normalsPerVertex[i].count;
    }

    j = 0;
    let vertexNormalData;
    for (i = 0; i < numIndices; i += 3) {
      vertexNormalData = normalsPerVertex[indices[i]];
      let index = vertexNormalData.indexOffset + vertexNormalData.currentCount;
      normalIndices[index] = j;
      vertexNormalData.currentCount++;

      vertexNormalData = normalsPerVertex[indices[i + 1]];
      index = vertexNormalData.indexOffset + vertexNormalData.currentCount;
      normalIndices[index] = j;
      vertexNormalData.currentCount++;

      vertexNormalData = normalsPerVertex[indices[i + 2]];
      index = vertexNormalData.indexOffset + vertexNormalData.currentCount;
      normalIndices[index] = j;
      vertexNormalData.currentCount++;

      j++;
    }

    const normalValues = new Float32Array(numVertices * 3);
    for (i = 0; i < numVertices; i++) {
      const i3 = i * 3;
      vertexNormalData = normalsPerVertex[i];
      Matrix2.Cartesian3.clone(Matrix2.Cartesian3.ZERO, normal);
      if (vertexNormalData.count > 0) {
        for (j = 0; j < vertexNormalData.count; j++) {
          Matrix2.Cartesian3.add(
            normal,
            normalsPerTriangle[normalIndices[vertexNormalData.indexOffset + j]],
            normal
          );
        }

        // We can run into an issue where a vertex is used with 2 primitives that have opposite winding order.
        if (
          Matrix2.Cartesian3.equalsEpsilon(Matrix2.Cartesian3.ZERO, normal, ComponentDatatype.CesiumMath.EPSILON10)
        ) {
          Matrix2.Cartesian3.clone(
            normalsPerTriangle[normalIndices[vertexNormalData.indexOffset]],
            normal
          );
        }
      }

      // We end up with a zero vector probably because of a degenerate triangle
      if (
        Matrix2.Cartesian3.equalsEpsilon(Matrix2.Cartesian3.ZERO, normal, ComponentDatatype.CesiumMath.EPSILON10)
      ) {
        // Default to (0,0,1)
        normal.z = 1.0;
      }

      Matrix2.Cartesian3.normalize(normal, normal);
      normalValues[i3] = normal.x;
      normalValues[i3 + 1] = normal.y;
      normalValues[i3 + 2] = normal.z;
    }

    geometry.attributes.normal = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: 3,
      values: normalValues,
    });

    return geometry;
  };

  const normalScratch = new Matrix2.Cartesian3();
  const normalScale = new Matrix2.Cartesian3();
  const tScratch = new Matrix2.Cartesian3();

  /**
   * Computes per-vertex tangents and bitangents for a geometry containing <code>TRIANGLES</code>.
   * The result is new <code>tangent</code> and <code>bitangent</code> attributes added to the geometry.
   * This assumes a counter-clockwise winding order.
   * <p>
   * Based on <a href="http://www.terathon.com/code/tangent.html">Computing Tangent Space Basis Vectors
   * for an Arbitrary Mesh</a> by Eric Lengyel.
   * </p>
   *
   * @param {Geometry} geometry The geometry to modify.
   * @returns {Geometry} The modified <code>geometry</code> argument with the computed <code>tangent</code> and <code>bitangent</code> attributes.
   *
   * @exception {DeveloperError} geometry.indices length must be greater than 0 and be a multiple of 3.
   * @exception {DeveloperError} geometry.primitiveType must be {@link PrimitiveType.TRIANGLES}.
   *
   * @example
   * Cesium.GeometryPipeline.computeTangentAndBiTangent(geometry);
   */
  GeometryPipeline.computeTangentAndBitangent = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug');

    const attributes = geometry.attributes;
    const indices = geometry.indices;

    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(attributes.position) || !defaultValue.defined(attributes.position.values)) {
      throw new RuntimeError.DeveloperError(
        "geometry.attributes.position.values is required."
      );
    }
    if (!defaultValue.defined(attributes.normal) || !defaultValue.defined(attributes.normal.values)) {
      throw new RuntimeError.DeveloperError("geometry.attributes.normal.values is required.");
    }
    if (!defaultValue.defined(attributes.st) || !defaultValue.defined(attributes.st.values)) {
      throw new RuntimeError.DeveloperError("geometry.attributes.st.values is required.");
    }
    if (!defaultValue.defined(indices)) {
      throw new RuntimeError.DeveloperError("geometry.indices is required.");
    }
    if (indices.length < 2 || indices.length % 3 !== 0) {
      throw new RuntimeError.DeveloperError(
        "geometry.indices length must be greater than 0 and be a multiple of 3."
      );
    }
    if (geometry.primitiveType !== GeometryAttribute.PrimitiveType.TRIANGLES) {
      throw new RuntimeError.DeveloperError(
        "geometry.primitiveType must be PrimitiveType.TRIANGLES."
      );
    }
    //>>includeEnd('debug');

    const vertices = geometry.attributes.position.values;
    const normals = geometry.attributes.normal.values;
    const st = geometry.attributes.st.values;

    const numVertices = geometry.attributes.position.values.length / 3;
    const numIndices = indices.length;
    const tan1 = new Array(numVertices * 3);

    let i;
    for (i = 0; i < tan1.length; i++) {
      tan1[i] = 0;
    }

    let i03;
    let i13;
    let i23;
    for (i = 0; i < numIndices; i += 3) {
      const i0 = indices[i];
      const i1 = indices[i + 1];
      const i2 = indices[i + 2];
      i03 = i0 * 3;
      i13 = i1 * 3;
      i23 = i2 * 3;
      const i02 = i0 * 2;
      const i12 = i1 * 2;
      const i22 = i2 * 2;

      const ux = vertices[i03];
      const uy = vertices[i03 + 1];
      const uz = vertices[i03 + 2];

      const wx = st[i02];
      const wy = st[i02 + 1];
      const t1 = st[i12 + 1] - wy;
      const t2 = st[i22 + 1] - wy;

      const r = 1.0 / ((st[i12] - wx) * t2 - (st[i22] - wx) * t1);
      const sdirx = (t2 * (vertices[i13] - ux) - t1 * (vertices[i23] - ux)) * r;
      const sdiry =
        (t2 * (vertices[i13 + 1] - uy) - t1 * (vertices[i23 + 1] - uy)) * r;
      const sdirz =
        (t2 * (vertices[i13 + 2] - uz) - t1 * (vertices[i23 + 2] - uz)) * r;

      tan1[i03] += sdirx;
      tan1[i03 + 1] += sdiry;
      tan1[i03 + 2] += sdirz;

      tan1[i13] += sdirx;
      tan1[i13 + 1] += sdiry;
      tan1[i13 + 2] += sdirz;

      tan1[i23] += sdirx;
      tan1[i23 + 1] += sdiry;
      tan1[i23 + 2] += sdirz;
    }

    const tangentValues = new Float32Array(numVertices * 3);
    const bitangentValues = new Float32Array(numVertices * 3);

    for (i = 0; i < numVertices; i++) {
      i03 = i * 3;
      i13 = i03 + 1;
      i23 = i03 + 2;

      const n = Matrix2.Cartesian3.fromArray(normals, i03, normalScratch);
      const t = Matrix2.Cartesian3.fromArray(tan1, i03, tScratch);
      const scalar = Matrix2.Cartesian3.dot(n, t);
      Matrix2.Cartesian3.multiplyByScalar(n, scalar, normalScale);
      Matrix2.Cartesian3.normalize(Matrix2.Cartesian3.subtract(t, normalScale, t), t);

      tangentValues[i03] = t.x;
      tangentValues[i13] = t.y;
      tangentValues[i23] = t.z;

      Matrix2.Cartesian3.normalize(Matrix2.Cartesian3.cross(n, t, t), t);

      bitangentValues[i03] = t.x;
      bitangentValues[i13] = t.y;
      bitangentValues[i23] = t.z;
    }

    geometry.attributes.tangent = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: 3,
      values: tangentValues,
    });

    geometry.attributes.bitangent = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: 3,
      values: bitangentValues,
    });

    return geometry;
  };

  const scratchCartesian2 = new Matrix2.Cartesian2();
  const toEncode1 = new Matrix2.Cartesian3();
  const toEncode2 = new Matrix2.Cartesian3();
  const toEncode3 = new Matrix2.Cartesian3();
  let encodeResult2 = new Matrix2.Cartesian2();
  /**
   * Compresses and packs geometry normal attribute values to save memory.
   *
   * @param {Geometry} geometry The geometry to modify.
   * @returns {Geometry} The modified <code>geometry</code> argument, with its normals compressed and packed.
   *
   * @example
   * geometry = Cesium.GeometryPipeline.compressVertices(geometry);
   */
  GeometryPipeline.compressVertices = function (geometry) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(geometry)) {
      throw new RuntimeError.DeveloperError("geometry is required.");
    }
    //>>includeEnd('debug');

    const extrudeAttribute = geometry.attributes.extrudeDirection;
    let i;
    let numVertices;
    if (defaultValue.defined(extrudeAttribute)) {
      //only shadow volumes use extrudeDirection, and shadow volumes use vertexFormat: POSITION_ONLY so we don't need to check other attributes
      const extrudeDirections = extrudeAttribute.values;
      numVertices = extrudeDirections.length / 3.0;
      const compressedDirections = new Float32Array(numVertices * 2);

      let i2 = 0;
      for (i = 0; i < numVertices; ++i) {
        Matrix2.Cartesian3.fromArray(extrudeDirections, i * 3.0, toEncode1);
        if (Matrix2.Cartesian3.equals(toEncode1, Matrix2.Cartesian3.ZERO)) {
          i2 += 2;
          continue;
        }
        encodeResult2 = AttributeCompression.AttributeCompression.octEncodeInRange(
          toEncode1,
          65535,
          encodeResult2
        );
        compressedDirections[i2++] = encodeResult2.x;
        compressedDirections[i2++] = encodeResult2.y;
      }

      geometry.attributes.compressedAttributes = new GeometryAttribute.GeometryAttribute({
        componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
        componentsPerAttribute: 2,
        values: compressedDirections,
      });
      delete geometry.attributes.extrudeDirection;
      return geometry;
    }

    const normalAttribute = geometry.attributes.normal;
    const stAttribute = geometry.attributes.st;

    const hasNormal = defaultValue.defined(normalAttribute);
    const hasSt = defaultValue.defined(stAttribute);
    if (!hasNormal && !hasSt) {
      return geometry;
    }

    const tangentAttribute = geometry.attributes.tangent;
    const bitangentAttribute = geometry.attributes.bitangent;

    const hasTangent = defaultValue.defined(tangentAttribute);
    const hasBitangent = defaultValue.defined(bitangentAttribute);

    let normals;
    let st;
    let tangents;
    let bitangents;

    if (hasNormal) {
      normals = normalAttribute.values;
    }
    if (hasSt) {
      st = stAttribute.values;
    }
    if (hasTangent) {
      tangents = tangentAttribute.values;
    }
    if (hasBitangent) {
      bitangents = bitangentAttribute.values;
    }

    const length = hasNormal ? normals.length : st.length;
    const numComponents = hasNormal ? 3.0 : 2.0;
    numVertices = length / numComponents;

    let compressedLength = numVertices;
    let numCompressedComponents = hasSt && hasNormal ? 2.0 : 1.0;
    numCompressedComponents += hasTangent || hasBitangent ? 1.0 : 0.0;
    compressedLength *= numCompressedComponents;

    const compressedAttributes = new Float32Array(compressedLength);

    let normalIndex = 0;
    for (i = 0; i < numVertices; ++i) {
      if (hasSt) {
        Matrix2.Cartesian2.fromArray(st, i * 2.0, scratchCartesian2);
        compressedAttributes[
          normalIndex++
        ] = AttributeCompression.AttributeCompression.compressTextureCoordinates(scratchCartesian2);
      }

      const index = i * 3.0;
      if (hasNormal && defaultValue.defined(tangents) && defaultValue.defined(bitangents)) {
        Matrix2.Cartesian3.fromArray(normals, index, toEncode1);
        Matrix2.Cartesian3.fromArray(tangents, index, toEncode2);
        Matrix2.Cartesian3.fromArray(bitangents, index, toEncode3);

        AttributeCompression.AttributeCompression.octPack(
          toEncode1,
          toEncode2,
          toEncode3,
          scratchCartesian2
        );
        compressedAttributes[normalIndex++] = scratchCartesian2.x;
        compressedAttributes[normalIndex++] = scratchCartesian2.y;
      } else {
        if (hasNormal) {
          Matrix2.Cartesian3.fromArray(normals, index, toEncode1);
          compressedAttributes[
            normalIndex++
          ] = AttributeCompression.AttributeCompression.octEncodeFloat(toEncode1);
        }

        if (hasTangent) {
          Matrix2.Cartesian3.fromArray(tangents, index, toEncode1);
          compressedAttributes[
            normalIndex++
          ] = AttributeCompression.AttributeCompression.octEncodeFloat(toEncode1);
        }

        if (hasBitangent) {
          Matrix2.Cartesian3.fromArray(bitangents, index, toEncode1);
          compressedAttributes[
            normalIndex++
          ] = AttributeCompression.AttributeCompression.octEncodeFloat(toEncode1);
        }
      }
    }

    geometry.attributes.compressedAttributes = new GeometryAttribute.GeometryAttribute({
      componentDatatype: ComponentDatatype.ComponentDatatype.FLOAT,
      componentsPerAttribute: numCompressedComponents,
      values: compressedAttributes,
    });

    if (hasNormal) {
      delete geometry.attributes.normal;
    }
    if (hasSt) {
      delete geometry.attributes.st;
    }
    if (hasBitangent) {
      delete geometry.attributes.bitangent;
    }
    if (hasTangent) {
      delete geometry.attributes.tangent;
    }

    return geometry;
  };

  function indexTriangles(geometry) {
    if (defaultValue.defined(geometry.indices)) {
      return geometry;
    }
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 3) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least three.");
    }
    if (numberOfVertices % 3 !== 0) {
      throw new RuntimeError.DeveloperError(
        "The number of vertices must be a multiple of three."
      );
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      numberOfVertices
    );
    for (let i = 0; i < numberOfVertices; ++i) {
      indices[i] = i;
    }

    geometry.indices = indices;
    return geometry;
  }

  function indexTriangleFan(geometry) {
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 3) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least three.");
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      (numberOfVertices - 2) * 3
    );
    indices[0] = 1;
    indices[1] = 0;
    indices[2] = 2;

    let indicesIndex = 3;
    for (let i = 3; i < numberOfVertices; ++i) {
      indices[indicesIndex++] = i - 1;
      indices[indicesIndex++] = 0;
      indices[indicesIndex++] = i;
    }

    geometry.indices = indices;
    geometry.primitiveType = GeometryAttribute.PrimitiveType.TRIANGLES;
    return geometry;
  }

  function indexTriangleStrip(geometry) {
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 3) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least 3.");
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      (numberOfVertices - 2) * 3
    );
    indices[0] = 0;
    indices[1] = 1;
    indices[2] = 2;

    if (numberOfVertices > 3) {
      indices[3] = 0;
      indices[4] = 2;
      indices[5] = 3;
    }

    let indicesIndex = 6;
    for (let i = 3; i < numberOfVertices - 1; i += 2) {
      indices[indicesIndex++] = i;
      indices[indicesIndex++] = i - 1;
      indices[indicesIndex++] = i + 1;

      if (i + 2 < numberOfVertices) {
        indices[indicesIndex++] = i;
        indices[indicesIndex++] = i + 1;
        indices[indicesIndex++] = i + 2;
      }
    }

    geometry.indices = indices;
    geometry.primitiveType = GeometryAttribute.PrimitiveType.TRIANGLES;
    return geometry;
  }

  function indexLines(geometry) {
    if (defaultValue.defined(geometry.indices)) {
      return geometry;
    }
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 2) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least two.");
    }
    if (numberOfVertices % 2 !== 0) {
      throw new RuntimeError.DeveloperError("The number of vertices must be a multiple of 2.");
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      numberOfVertices
    );
    for (let i = 0; i < numberOfVertices; ++i) {
      indices[i] = i;
    }

    geometry.indices = indices;
    return geometry;
  }

  function indexLineStrip(geometry) {
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 2) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least two.");
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      (numberOfVertices - 1) * 2
    );
    indices[0] = 0;
    indices[1] = 1;
    let indicesIndex = 2;
    for (let i = 2; i < numberOfVertices; ++i) {
      indices[indicesIndex++] = i - 1;
      indices[indicesIndex++] = i;
    }

    geometry.indices = indices;
    geometry.primitiveType = GeometryAttribute.PrimitiveType.LINES;
    return geometry;
  }

  function indexLineLoop(geometry) {
    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);

    //>>includeStart('debug', pragmas.debug);
    if (numberOfVertices < 2) {
      throw new RuntimeError.DeveloperError("The number of vertices must be at least two.");
    }
    //>>includeEnd('debug');

    const indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      numberOfVertices * 2
    );

    indices[0] = 0;
    indices[1] = 1;

    let indicesIndex = 2;
    for (let i = 2; i < numberOfVertices; ++i) {
      indices[indicesIndex++] = i - 1;
      indices[indicesIndex++] = i;
    }

    indices[indicesIndex++] = numberOfVertices - 1;
    indices[indicesIndex] = 0;

    geometry.indices = indices;
    geometry.primitiveType = GeometryAttribute.PrimitiveType.LINES;
    return geometry;
  }

  function indexPrimitive(geometry) {
    switch (geometry.primitiveType) {
      case GeometryAttribute.PrimitiveType.TRIANGLE_FAN:
        return indexTriangleFan(geometry);
      case GeometryAttribute.PrimitiveType.TRIANGLE_STRIP:
        return indexTriangleStrip(geometry);
      case GeometryAttribute.PrimitiveType.TRIANGLES:
        return indexTriangles(geometry);
      case GeometryAttribute.PrimitiveType.LINE_STRIP:
        return indexLineStrip(geometry);
      case GeometryAttribute.PrimitiveType.LINE_LOOP:
        return indexLineLoop(geometry);
      case GeometryAttribute.PrimitiveType.LINES:
        return indexLines(geometry);
    }

    return geometry;
  }

  function offsetPointFromXZPlane(p, isBehind) {
    if (Math.abs(p.y) < ComponentDatatype.CesiumMath.EPSILON6) {
      if (isBehind) {
        p.y = -ComponentDatatype.CesiumMath.EPSILON6;
      } else {
        p.y = ComponentDatatype.CesiumMath.EPSILON6;
      }
    }
  }

  function offsetTriangleFromXZPlane(p0, p1, p2) {
    if (p0.y !== 0.0 && p1.y !== 0.0 && p2.y !== 0.0) {
      offsetPointFromXZPlane(p0, p0.y < 0.0);
      offsetPointFromXZPlane(p1, p1.y < 0.0);
      offsetPointFromXZPlane(p2, p2.y < 0.0);
      return;
    }

    const p0y = Math.abs(p0.y);
    const p1y = Math.abs(p1.y);
    const p2y = Math.abs(p2.y);

    let sign;
    if (p0y > p1y) {
      if (p0y > p2y) {
        sign = ComponentDatatype.CesiumMath.sign(p0.y);
      } else {
        sign = ComponentDatatype.CesiumMath.sign(p2.y);
      }
    } else if (p1y > p2y) {
      sign = ComponentDatatype.CesiumMath.sign(p1.y);
    } else {
      sign = ComponentDatatype.CesiumMath.sign(p2.y);
    }

    const isBehind = sign < 0.0;
    offsetPointFromXZPlane(p0, isBehind);
    offsetPointFromXZPlane(p1, isBehind);
    offsetPointFromXZPlane(p2, isBehind);
  }

  const c3 = new Matrix2.Cartesian3();
  function getXZIntersectionOffsetPoints(p, p1, u1, v1) {
    Matrix2.Cartesian3.add(
      p,
      Matrix2.Cartesian3.multiplyByScalar(
        Matrix2.Cartesian3.subtract(p1, p, c3),
        p.y / (p.y - p1.y),
        c3
      ),
      u1
    );
    Matrix2.Cartesian3.clone(u1, v1);
    offsetPointFromXZPlane(u1, true);
    offsetPointFromXZPlane(v1, false);
  }

  const u1 = new Matrix2.Cartesian3();
  const u2 = new Matrix2.Cartesian3();
  const q1 = new Matrix2.Cartesian3();
  const q2 = new Matrix2.Cartesian3();

  const splitTriangleResult = {
    positions: new Array(7),
    indices: new Array(3 * 3),
  };

  function splitTriangle(p0, p1, p2) {
    // In WGS84 coordinates, for a triangle approximately on the
    // ellipsoid to cross the IDL, first it needs to be on the
    // negative side of the plane x = 0.
    if (p0.x >= 0.0 || p1.x >= 0.0 || p2.x >= 0.0) {
      return undefined;
    }

    offsetTriangleFromXZPlane(p0, p1, p2);

    const p0Behind = p0.y < 0.0;
    const p1Behind = p1.y < 0.0;
    const p2Behind = p2.y < 0.0;

    let numBehind = 0;
    numBehind += p0Behind ? 1 : 0;
    numBehind += p1Behind ? 1 : 0;
    numBehind += p2Behind ? 1 : 0;

    const indices = splitTriangleResult.indices;

    if (numBehind === 1) {
      indices[1] = 3;
      indices[2] = 4;
      indices[5] = 6;
      indices[7] = 6;
      indices[8] = 5;

      if (p0Behind) {
        getXZIntersectionOffsetPoints(p0, p1, u1, q1);
        getXZIntersectionOffsetPoints(p0, p2, u2, q2);

        indices[0] = 0;
        indices[3] = 1;
        indices[4] = 2;
        indices[6] = 1;
      } else if (p1Behind) {
        getXZIntersectionOffsetPoints(p1, p2, u1, q1);
        getXZIntersectionOffsetPoints(p1, p0, u2, q2);

        indices[0] = 1;
        indices[3] = 2;
        indices[4] = 0;
        indices[6] = 2;
      } else if (p2Behind) {
        getXZIntersectionOffsetPoints(p2, p0, u1, q1);
        getXZIntersectionOffsetPoints(p2, p1, u2, q2);

        indices[0] = 2;
        indices[3] = 0;
        indices[4] = 1;
        indices[6] = 0;
      }
    } else if (numBehind === 2) {
      indices[2] = 4;
      indices[4] = 4;
      indices[5] = 3;
      indices[7] = 5;
      indices[8] = 6;

      if (!p0Behind) {
        getXZIntersectionOffsetPoints(p0, p1, u1, q1);
        getXZIntersectionOffsetPoints(p0, p2, u2, q2);

        indices[0] = 1;
        indices[1] = 2;
        indices[3] = 1;
        indices[6] = 0;
      } else if (!p1Behind) {
        getXZIntersectionOffsetPoints(p1, p2, u1, q1);
        getXZIntersectionOffsetPoints(p1, p0, u2, q2);

        indices[0] = 2;
        indices[1] = 0;
        indices[3] = 2;
        indices[6] = 1;
      } else if (!p2Behind) {
        getXZIntersectionOffsetPoints(p2, p0, u1, q1);
        getXZIntersectionOffsetPoints(p2, p1, u2, q2);

        indices[0] = 0;
        indices[1] = 1;
        indices[3] = 0;
        indices[6] = 2;
      }
    }

    const positions = splitTriangleResult.positions;
    positions[0] = p0;
    positions[1] = p1;
    positions[2] = p2;
    positions.length = 3;

    if (numBehind === 1 || numBehind === 2) {
      positions[3] = u1;
      positions[4] = u2;
      positions[5] = q1;
      positions[6] = q2;
      positions.length = 7;
    }

    return splitTriangleResult;
  }

  function updateGeometryAfterSplit(geometry, computeBoundingSphere) {
    const attributes = geometry.attributes;

    if (attributes.position.values.length === 0) {
      return undefined;
    }

    for (const property in attributes) {
      if (
        attributes.hasOwnProperty(property) &&
        defaultValue.defined(attributes[property]) &&
        defaultValue.defined(attributes[property].values)
      ) {
        const attribute = attributes[property];
        attribute.values = ComponentDatatype.ComponentDatatype.createTypedArray(
          attribute.componentDatatype,
          attribute.values
        );
      }
    }

    const numberOfVertices = GeometryAttribute.Geometry.computeNumberOfVertices(geometry);
    geometry.indices = IndexDatatype.IndexDatatype.createTypedArray(
      numberOfVertices,
      geometry.indices
    );

    if (computeBoundingSphere) {
      geometry.boundingSphere = Transforms.BoundingSphere.fromVertices(
        attributes.position.values
      );
    }

    return geometry;
  }

  function copyGeometryForSplit(geometry) {
    const attributes = geometry.attributes;
    const copiedAttributes = {};

    for (const property in attributes) {
      if (
        attributes.hasOwnProperty(property) &&
        defaultValue.defined(attributes[property]) &&
        defaultValue.defined(attributes[property].values)
      ) {
        const attribute = attributes[property];
        copiedAttributes[property] = new GeometryAttribute.GeometryAttribute({
          componentDatatype: attribute.componentDatatype,
          componentsPerAttribute: attribute.componentsPerAttribute,
          normalize: attribute.normalize,
          values: [],
        });
      }
    }

    return new GeometryAttribute.Geometry({
      attributes: copiedAttributes,
      indices: [],
      primitiveType: geometry.primitiveType,
    });
  }

  function updateInstanceAfterSplit(instance, westGeometry, eastGeometry) {
    const computeBoundingSphere = defaultValue.defined(instance.geometry.boundingSphere);

    westGeometry = updateGeometryAfterSplit(westGeometry, computeBoundingSphere);
    eastGeometry = updateGeometryAfterSplit(eastGeometry, computeBoundingSphere);

    if (defaultValue.defined(eastGeometry) && !defaultValue.defined(westGeometry)) {
      instance.geometry = eastGeometry;
    } else if (!defaultValue.defined(eastGeometry) && defaultValue.defined(westGeometry)) {
      instance.geometry = westGeometry;
    } else {
      instance.westHemisphereGeometry = westGeometry;
      instance.eastHemisphereGeometry = eastGeometry;
      instance.geometry = undefined;
    }
  }

  function generateBarycentricInterpolateFunction(
    CartesianType,
    numberOfComponents
  ) {
    const v0Scratch = new CartesianType();
    const v1Scratch = new CartesianType();
    const v2Scratch = new CartesianType();

    return function (
      i0,
      i1,
      i2,
      coords,
      sourceValues,
      currentValues,
      insertedIndex,
      normalize
    ) {
      const v0 = CartesianType.fromArray(
        sourceValues,
        i0 * numberOfComponents,
        v0Scratch
      );
      const v1 = CartesianType.fromArray(
        sourceValues,
        i1 * numberOfComponents,
        v1Scratch
      );
      const v2 = CartesianType.fromArray(
        sourceValues,
        i2 * numberOfComponents,
        v2Scratch
      );

      CartesianType.multiplyByScalar(v0, coords.x, v0);
      CartesianType.multiplyByScalar(v1, coords.y, v1);
      CartesianType.multiplyByScalar(v2, coords.z, v2);

      const value = CartesianType.add(v0, v1, v0);
      CartesianType.add(value, v2, value);

      if (normalize) {
        CartesianType.normalize(value, value);
      }

      CartesianType.pack(
        value,
        currentValues,
        insertedIndex * numberOfComponents
      );
    };
  }

  const interpolateAndPackCartesian4 = generateBarycentricInterpolateFunction(
    Matrix2.Cartesian4,
    4
  );
  const interpolateAndPackCartesian3 = generateBarycentricInterpolateFunction(
    Matrix2.Cartesian3,
    3
  );
  const interpolateAndPackCartesian2 = generateBarycentricInterpolateFunction(
    Matrix2.Cartesian2,
    2
  );
  const interpolateAndPackBoolean = function (
    i0,
    i1,
    i2,
    coords,
    sourceValues,
    currentValues,
    insertedIndex
  ) {
    const v1 = sourceValues[i0] * coords.x;
    const v2 = sourceValues[i1] * coords.y;
    const v3 = sourceValues[i2] * coords.z;
    currentValues[insertedIndex] = v1 + v2 + v3 > ComponentDatatype.CesiumMath.EPSILON6 ? 1 : 0;
  };

  const p0Scratch = new Matrix2.Cartesian3();
  const p1Scratch = new Matrix2.Cartesian3();
  const p2Scratch = new Matrix2.Cartesian3();
  const barycentricScratch = new Matrix2.Cartesian3();

  function computeTriangleAttributes(
    i0,
    i1,
    i2,
    point,
    positions,
    normals,
    tangents,
    bitangents,
    texCoords,
    extrudeDirections,
    applyOffset,
    currentAttributes,
    customAttributeNames,
    customAttributesLength,
    allAttributes,
    insertedIndex
  ) {
    if (
      !defaultValue.defined(normals) &&
      !defaultValue.defined(tangents) &&
      !defaultValue.defined(bitangents) &&
      !defaultValue.defined(texCoords) &&
      !defaultValue.defined(extrudeDirections) &&
      customAttributesLength === 0
    ) {
      return;
    }

    const p0 = Matrix2.Cartesian3.fromArray(positions, i0 * 3, p0Scratch);
    const p1 = Matrix2.Cartesian3.fromArray(positions, i1 * 3, p1Scratch);
    const p2 = Matrix2.Cartesian3.fromArray(positions, i2 * 3, p2Scratch);
    const coords = barycentricCoordinates(point, p0, p1, p2, barycentricScratch);
    if (!defaultValue.defined(coords)) {
      return;
    }

    if (defaultValue.defined(normals)) {
      interpolateAndPackCartesian3(
        i0,
        i1,
        i2,
        coords,
        normals,
        currentAttributes.normal.values,
        insertedIndex,
        true
      );
    }

    if (defaultValue.defined(extrudeDirections)) {
      const d0 = Matrix2.Cartesian3.fromArray(extrudeDirections, i0 * 3, p0Scratch);
      const d1 = Matrix2.Cartesian3.fromArray(extrudeDirections, i1 * 3, p1Scratch);
      const d2 = Matrix2.Cartesian3.fromArray(extrudeDirections, i2 * 3, p2Scratch);

      Matrix2.Cartesian3.multiplyByScalar(d0, coords.x, d0);
      Matrix2.Cartesian3.multiplyByScalar(d1, coords.y, d1);
      Matrix2.Cartesian3.multiplyByScalar(d2, coords.z, d2);

      let direction;
      if (
        !Matrix2.Cartesian3.equals(d0, Matrix2.Cartesian3.ZERO) ||
        !Matrix2.Cartesian3.equals(d1, Matrix2.Cartesian3.ZERO) ||
        !Matrix2.Cartesian3.equals(d2, Matrix2.Cartesian3.ZERO)
      ) {
        direction = Matrix2.Cartesian3.add(d0, d1, d0);
        Matrix2.Cartesian3.add(direction, d2, direction);
        Matrix2.Cartesian3.normalize(direction, direction);
      } else {
        direction = p0Scratch;
        direction.x = 0;
        direction.y = 0;
        direction.z = 0;
      }
      Matrix2.Cartesian3.pack(
        direction,
        currentAttributes.extrudeDirection.values,
        insertedIndex * 3
      );
    }

    if (defaultValue.defined(applyOffset)) {
      interpolateAndPackBoolean(
        i0,
        i1,
        i2,
        coords,
        applyOffset,
        currentAttributes.applyOffset.values,
        insertedIndex
      );
    }

    if (defaultValue.defined(tangents)) {
      interpolateAndPackCartesian3(
        i0,
        i1,
        i2,
        coords,
        tangents,
        currentAttributes.tangent.values,
        insertedIndex,
        true
      );
    }

    if (defaultValue.defined(bitangents)) {
      interpolateAndPackCartesian3(
        i0,
        i1,
        i2,
        coords,
        bitangents,
        currentAttributes.bitangent.values,
        insertedIndex,
        true
      );
    }

    if (defaultValue.defined(texCoords)) {
      interpolateAndPackCartesian2(
        i0,
        i1,
        i2,
        coords,
        texCoords,
        currentAttributes.st.values,
        insertedIndex
      );
    }

    if (customAttributesLength > 0) {
      for (let i = 0; i < customAttributesLength; i++) {
        const attributeName = customAttributeNames[i];
        genericInterpolate(
          i0,
          i1,
          i2,
          coords,
          insertedIndex,
          allAttributes[attributeName],
          currentAttributes[attributeName]
        );
      }
    }
  }

  function genericInterpolate(
    i0,
    i1,
    i2,
    coords,
    insertedIndex,
    sourceAttribute,
    currentAttribute
  ) {
    const componentsPerAttribute = sourceAttribute.componentsPerAttribute;
    const sourceValues = sourceAttribute.values;
    const currentValues = currentAttribute.values;
    switch (componentsPerAttribute) {
      case 4:
        interpolateAndPackCartesian4(
          i0,
          i1,
          i2,
          coords,
          sourceValues,
          currentValues,
          insertedIndex,
          false
        );
        break;
      case 3:
        interpolateAndPackCartesian3(
          i0,
          i1,
          i2,
          coords,
          sourceValues,
          currentValues,
          insertedIndex,
          false
        );
        break;
      case 2:
        interpolateAndPackCartesian2(
          i0,
          i1,
          i2,
          coords,
          sourceValues,
          currentValues,
          insertedIndex,
          false
        );
        break;
      default:
        currentValues[insertedIndex] =
          sourceValues[i0] * coords.x +
          sourceValues[i1] * coords.y +
          sourceValues[i2] * coords.z;
    }
  }

  function insertSplitPoint(
    currentAttributes,
    currentIndices,
    currentIndexMap,
    indices,
    currentIndex,
    point
  ) {
    const insertIndex = currentAttributes.position.values.length / 3;

    if (currentIndex !== -1) {
      const prevIndex = indices[currentIndex];
      const newIndex = currentIndexMap[prevIndex];

      if (newIndex === -1) {
        currentIndexMap[prevIndex] = insertIndex;
        currentAttributes.position.values.push(point.x, point.y, point.z);
        currentIndices.push(insertIndex);
        return insertIndex;
      }

      currentIndices.push(newIndex);
      return newIndex;
    }

    currentAttributes.position.values.push(point.x, point.y, point.z);
    currentIndices.push(insertIndex);
    return insertIndex;
  }

  const NAMED_ATTRIBUTES = {
    position: true,
    normal: true,
    bitangent: true,
    tangent: true,
    st: true,
    extrudeDirection: true,
    applyOffset: true,
  };
  function splitLongitudeTriangles(instance) {
    const geometry = instance.geometry;
    const attributes = geometry.attributes;
    const positions = attributes.position.values;
    const normals = defaultValue.defined(attributes.normal)
      ? attributes.normal.values
      : undefined;
    const bitangents = defaultValue.defined(attributes.bitangent)
      ? attributes.bitangent.values
      : undefined;
    const tangents = defaultValue.defined(attributes.tangent)
      ? attributes.tangent.values
      : undefined;
    const texCoords = defaultValue.defined(attributes.st) ? attributes.st.values : undefined;
    const extrudeDirections = defaultValue.defined(attributes.extrudeDirection)
      ? attributes.extrudeDirection.values
      : undefined;
    const applyOffset = defaultValue.defined(attributes.applyOffset)
      ? attributes.applyOffset.values
      : undefined;
    const indices = geometry.indices;

    const customAttributeNames = [];
    for (const attributeName in attributes) {
      if (
        attributes.hasOwnProperty(attributeName) &&
        !NAMED_ATTRIBUTES[attributeName] &&
        defaultValue.defined(attributes[attributeName])
      ) {
        customAttributeNames.push(attributeName);
      }
    }
    const customAttributesLength = customAttributeNames.length;

    const eastGeometry = copyGeometryForSplit(geometry);
    const westGeometry = copyGeometryForSplit(geometry);

    let currentAttributes;
    let currentIndices;
    let currentIndexMap;
    let insertedIndex;
    let i;

    const westGeometryIndexMap = [];
    westGeometryIndexMap.length = positions.length / 3;

    const eastGeometryIndexMap = [];
    eastGeometryIndexMap.length = positions.length / 3;

    for (i = 0; i < westGeometryIndexMap.length; ++i) {
      westGeometryIndexMap[i] = -1;
      eastGeometryIndexMap[i] = -1;
    }

    const len = indices.length;
    for (i = 0; i < len; i += 3) {
      const i0 = indices[i];
      const i1 = indices[i + 1];
      const i2 = indices[i + 2];

      let p0 = Matrix2.Cartesian3.fromArray(positions, i0 * 3);
      let p1 = Matrix2.Cartesian3.fromArray(positions, i1 * 3);
      let p2 = Matrix2.Cartesian3.fromArray(positions, i2 * 3);

      const result = splitTriangle(p0, p1, p2);
      if (defaultValue.defined(result) && result.positions.length > 3) {
        const resultPositions = result.positions;
        const resultIndices = result.indices;
        const resultLength = resultIndices.length;

        for (let j = 0; j < resultLength; ++j) {
          const resultIndex = resultIndices[j];
          const point = resultPositions[resultIndex];

          if (point.y < 0.0) {
            currentAttributes = westGeometry.attributes;
            currentIndices = westGeometry.indices;
            currentIndexMap = westGeometryIndexMap;
          } else {
            currentAttributes = eastGeometry.attributes;
            currentIndices = eastGeometry.indices;
            currentIndexMap = eastGeometryIndexMap;
          }

          insertedIndex = insertSplitPoint(
            currentAttributes,
            currentIndices,
            currentIndexMap,
            indices,
            resultIndex < 3 ? i + resultIndex : -1,
            point
          );
          computeTriangleAttributes(
            i0,
            i1,
            i2,
            point,
            positions,
            normals,
            tangents,
            bitangents,
            texCoords,
            extrudeDirections,
            applyOffset,
            currentAttributes,
            customAttributeNames,
            customAttributesLength,
            attributes,
            insertedIndex
          );
        }
      } else {
        if (defaultValue.defined(result)) {
          p0 = result.positions[0];
          p1 = result.positions[1];
          p2 = result.positions[2];
        }

        if (p0.y < 0.0) {
          currentAttributes = westGeometry.attributes;
          currentIndices = westGeometry.indices;
          currentIndexMap = westGeometryIndexMap;
        } else {
          currentAttributes = eastGeometry.attributes;
          currentIndices = eastGeometry.indices;
          currentIndexMap = eastGeometryIndexMap;
        }

        insertedIndex = insertSplitPoint(
          currentAttributes,
          currentIndices,
          currentIndexMap,
          indices,
          i,
          p0
        );
        computeTriangleAttributes(
          i0,
          i1,
          i2,
          p0,
          positions,
          normals,
          tangents,
          bitangents,
          texCoords,
          extrudeDirections,
          applyOffset,
          currentAttributes,
          customAttributeNames,
          customAttributesLength,
          attributes,
          insertedIndex
        );

        insertedIndex = insertSplitPoint(
          currentAttributes,
          currentIndices,
          currentIndexMap,
          indices,
          i + 1,
          p1
        );
        computeTriangleAttributes(
          i0,
          i1,
          i2,
          p1,
          positions,
          normals,
          tangents,
          bitangents,
          texCoords,
          extrudeDirections,
          applyOffset,
          currentAttributes,
          customAttributeNames,
          customAttributesLength,
          attributes,
          insertedIndex
        );

        insertedIndex = insertSplitPoint(
          currentAttributes,
          currentIndices,
          currentIndexMap,
          indices,
          i + 2,
          p2
        );
        computeTriangleAttributes(
          i0,
          i1,
          i2,
          p2,
          positions,
          normals,
          tangents,
          bitangents,
          texCoords,
          extrudeDirections,
          applyOffset,
          currentAttributes,
          customAttributeNames,
          customAttributesLength,
          attributes,
          insertedIndex
        );
      }
    }

    updateInstanceAfterSplit(instance, westGeometry, eastGeometry);
  }

  const xzPlane = Plane.Plane.fromPointNormal(Matrix2.Cartesian3.ZERO, Matrix2.Cartesian3.UNIT_Y);

  const offsetScratch = new Matrix2.Cartesian3();
  const offsetPointScratch = new Matrix2.Cartesian3();

  function computeLineAttributes(
    i0,
    i1,
    point,
    positions,
    insertIndex,
    currentAttributes,
    applyOffset
  ) {
    if (!defaultValue.defined(applyOffset)) {
      return;
    }

    const p0 = Matrix2.Cartesian3.fromArray(positions, i0 * 3, p0Scratch);
    if (Matrix2.Cartesian3.equalsEpsilon(p0, point, ComponentDatatype.CesiumMath.EPSILON10)) {
      currentAttributes.applyOffset.values[insertIndex] = applyOffset[i0];
    } else {
      currentAttributes.applyOffset.values[insertIndex] = applyOffset[i1];
    }
  }

  function splitLongitudeLines(instance) {
    const geometry = instance.geometry;
    const attributes = geometry.attributes;
    const positions = attributes.position.values;
    const applyOffset = defaultValue.defined(attributes.applyOffset)
      ? attributes.applyOffset.values
      : undefined;
    const indices = geometry.indices;

    const eastGeometry = copyGeometryForSplit(geometry);
    const westGeometry = copyGeometryForSplit(geometry);

    let i;
    const length = indices.length;

    const westGeometryIndexMap = [];
    westGeometryIndexMap.length = positions.length / 3;

    const eastGeometryIndexMap = [];
    eastGeometryIndexMap.length = positions.length / 3;

    for (i = 0; i < westGeometryIndexMap.length; ++i) {
      westGeometryIndexMap[i] = -1;
      eastGeometryIndexMap[i] = -1;
    }

    for (i = 0; i < length; i += 2) {
      const i0 = indices[i];
      const i1 = indices[i + 1];

      const p0 = Matrix2.Cartesian3.fromArray(positions, i0 * 3, p0Scratch);
      const p1 = Matrix2.Cartesian3.fromArray(positions, i1 * 3, p1Scratch);
      let insertIndex;

      if (Math.abs(p0.y) < ComponentDatatype.CesiumMath.EPSILON6) {
        if (p0.y < 0.0) {
          p0.y = -ComponentDatatype.CesiumMath.EPSILON6;
        } else {
          p0.y = ComponentDatatype.CesiumMath.EPSILON6;
        }
      }

      if (Math.abs(p1.y) < ComponentDatatype.CesiumMath.EPSILON6) {
        if (p1.y < 0.0) {
          p1.y = -ComponentDatatype.CesiumMath.EPSILON6;
        } else {
          p1.y = ComponentDatatype.CesiumMath.EPSILON6;
        }
      }

      let p0Attributes = eastGeometry.attributes;
      let p0Indices = eastGeometry.indices;
      let p0IndexMap = eastGeometryIndexMap;
      let p1Attributes = westGeometry.attributes;
      let p1Indices = westGeometry.indices;
      let p1IndexMap = westGeometryIndexMap;

      const intersection = IntersectionTests.IntersectionTests.lineSegmentPlane(
        p0,
        p1,
        xzPlane,
        p2Scratch
      );
      if (defaultValue.defined(intersection)) {
        // move point on the xz-plane slightly away from the plane
        const offset = Matrix2.Cartesian3.multiplyByScalar(
          Matrix2.Cartesian3.UNIT_Y,
          5.0 * ComponentDatatype.CesiumMath.EPSILON9,
          offsetScratch
        );
        if (p0.y < 0.0) {
          Matrix2.Cartesian3.negate(offset, offset);

          p0Attributes = westGeometry.attributes;
          p0Indices = westGeometry.indices;
          p0IndexMap = westGeometryIndexMap;
          p1Attributes = eastGeometry.attributes;
          p1Indices = eastGeometry.indices;
          p1IndexMap = eastGeometryIndexMap;
        }

        const offsetPoint = Matrix2.Cartesian3.add(
          intersection,
          offset,
          offsetPointScratch
        );

        insertIndex = insertSplitPoint(
          p0Attributes,
          p0Indices,
          p0IndexMap,
          indices,
          i,
          p0
        );
        computeLineAttributes(
          i0,
          i1,
          p0,
          positions,
          insertIndex,
          p0Attributes,
          applyOffset
        );

        insertIndex = insertSplitPoint(
          p0Attributes,
          p0Indices,
          p0IndexMap,
          indices,
          -1,
          offsetPoint
        );
        computeLineAttributes(
          i0,
          i1,
          offsetPoint,
          positions,
          insertIndex,
          p0Attributes,
          applyOffset
        );

        Matrix2.Cartesian3.negate(offset, offset);
        Matrix2.Cartesian3.add(intersection, offset, offsetPoint);
        insertIndex = insertSplitPoint(
          p1Attributes,
          p1Indices,
          p1IndexMap,
          indices,
          -1,
          offsetPoint
        );
        computeLineAttributes(
          i0,
          i1,
          offsetPoint,
          positions,
          insertIndex,
          p1Attributes,
          applyOffset
        );

        insertIndex = insertSplitPoint(
          p1Attributes,
          p1Indices,
          p1IndexMap,
          indices,
          i + 1,
          p1
        );
        computeLineAttributes(
          i0,
          i1,
          p1,
          positions,
          insertIndex,
          p1Attributes,
          applyOffset
        );
      } else {
        let currentAttributes;
        let currentIndices;
        let currentIndexMap;

        if (p0.y < 0.0) {
          currentAttributes = westGeometry.attributes;
          currentIndices = westGeometry.indices;
          currentIndexMap = westGeometryIndexMap;
        } else {
          currentAttributes = eastGeometry.attributes;
          currentIndices = eastGeometry.indices;
          currentIndexMap = eastGeometryIndexMap;
        }

        insertIndex = insertSplitPoint(
          currentAttributes,
          currentIndices,
          currentIndexMap,
          indices,
          i,
          p0
        );
        computeLineAttributes(
          i0,
          i1,
          p0,
          positions,
          insertIndex,
          currentAttributes,
          applyOffset
        );

        insertIndex = insertSplitPoint(
          currentAttributes,
          currentIndices,
          currentIndexMap,
          indices,
          i + 1,
          p1
        );
        computeLineAttributes(
          i0,
          i1,
          p1,
          positions,
          insertIndex,
          currentAttributes,
          applyOffset
        );
      }
    }

    updateInstanceAfterSplit(instance, westGeometry, eastGeometry);
  }

  const cartesian2Scratch0 = new Matrix2.Cartesian2();
  const cartesian2Scratch1 = new Matrix2.Cartesian2();

  const cartesian3Scratch0 = new Matrix2.Cartesian3();
  const cartesian3Scratch2 = new Matrix2.Cartesian3();
  const cartesian3Scratch3 = new Matrix2.Cartesian3();
  const cartesian3Scratch4 = new Matrix2.Cartesian3();
  const cartesian3Scratch5 = new Matrix2.Cartesian3();
  const cartesian3Scratch6 = new Matrix2.Cartesian3();

  const cartesian4Scratch0 = new Matrix2.Cartesian4();

  function updateAdjacencyAfterSplit(geometry) {
    const attributes = geometry.attributes;
    const positions = attributes.position.values;
    const prevPositions = attributes.prevPosition.values;
    const nextPositions = attributes.nextPosition.values;

    const length = positions.length;
    for (let j = 0; j < length; j += 3) {
      const position = Matrix2.Cartesian3.unpack(positions, j, cartesian3Scratch0);
      if (position.x > 0.0) {
        continue;
      }

      const prevPosition = Matrix2.Cartesian3.unpack(
        prevPositions,
        j,
        cartesian3Scratch2
      );
      if (
        (position.y < 0.0 && prevPosition.y > 0.0) ||
        (position.y > 0.0 && prevPosition.y < 0.0)
      ) {
        if (j - 3 > 0) {
          prevPositions[j] = positions[j - 3];
          prevPositions[j + 1] = positions[j - 2];
          prevPositions[j + 2] = positions[j - 1];
        } else {
          Matrix2.Cartesian3.pack(position, prevPositions, j);
        }
      }

      const nextPosition = Matrix2.Cartesian3.unpack(
        nextPositions,
        j,
        cartesian3Scratch3
      );
      if (
        (position.y < 0.0 && nextPosition.y > 0.0) ||
        (position.y > 0.0 && nextPosition.y < 0.0)
      ) {
        if (j + 3 < length) {
          nextPositions[j] = positions[j + 3];
          nextPositions[j + 1] = positions[j + 4];
          nextPositions[j + 2] = positions[j + 5];
        } else {
          Matrix2.Cartesian3.pack(position, nextPositions, j);
        }
      }
    }
  }

  const offsetScalar = 5.0 * ComponentDatatype.CesiumMath.EPSILON9;
  const coplanarOffset = ComponentDatatype.CesiumMath.EPSILON6;

  function splitLongitudePolyline(instance) {
    const geometry = instance.geometry;
    const attributes = geometry.attributes;
    const positions = attributes.position.values;
    const prevPositions = attributes.prevPosition.values;
    const nextPositions = attributes.nextPosition.values;
    const expandAndWidths = attributes.expandAndWidth.values;

    const texCoords = defaultValue.defined(attributes.st) ? attributes.st.values : undefined;
    const colors = defaultValue.defined(attributes.color)
      ? attributes.color.values
      : undefined;

    const eastGeometry = copyGeometryForSplit(geometry);
    const westGeometry = copyGeometryForSplit(geometry);

    let i;
    let j;
    let index;

    let intersectionFound = false;

    const length = positions.length / 3;
    for (i = 0; i < length; i += 4) {
      const i0 = i;
      const i2 = i + 2;

      const p0 = Matrix2.Cartesian3.fromArray(positions, i0 * 3, cartesian3Scratch0);
      const p2 = Matrix2.Cartesian3.fromArray(positions, i2 * 3, cartesian3Scratch2);

      // Offset points that are close to the 180 longitude and change the previous/next point
      // to be the same offset point so it can be projected to 2D. There is special handling in the
      // shader for when position == prevPosition || position == nextPosition.
      if (Math.abs(p0.y) < coplanarOffset) {
        p0.y = coplanarOffset * (p2.y < 0.0 ? -1.0 : 1.0);
        positions[i * 3 + 1] = p0.y;
        positions[(i + 1) * 3 + 1] = p0.y;

        for (j = i0 * 3; j < i0 * 3 + 4 * 3; j += 3) {
          prevPositions[j] = positions[i * 3];
          prevPositions[j + 1] = positions[i * 3 + 1];
          prevPositions[j + 2] = positions[i * 3 + 2];
        }
      }

      // Do the same but for when the line crosses 180 longitude in the opposite direction.
      if (Math.abs(p2.y) < coplanarOffset) {
        p2.y = coplanarOffset * (p0.y < 0.0 ? -1.0 : 1.0);
        positions[(i + 2) * 3 + 1] = p2.y;
        positions[(i + 3) * 3 + 1] = p2.y;

        for (j = i0 * 3; j < i0 * 3 + 4 * 3; j += 3) {
          nextPositions[j] = positions[(i + 2) * 3];
          nextPositions[j + 1] = positions[(i + 2) * 3 + 1];
          nextPositions[j + 2] = positions[(i + 2) * 3 + 2];
        }
      }

      let p0Attributes = eastGeometry.attributes;
      let p0Indices = eastGeometry.indices;
      let p2Attributes = westGeometry.attributes;
      let p2Indices = westGeometry.indices;

      const intersection = IntersectionTests.IntersectionTests.lineSegmentPlane(
        p0,
        p2,
        xzPlane,
        cartesian3Scratch4
      );
      if (defaultValue.defined(intersection)) {
        intersectionFound = true;

        // move point on the xz-plane slightly away from the plane
        const offset = Matrix2.Cartesian3.multiplyByScalar(
          Matrix2.Cartesian3.UNIT_Y,
          offsetScalar,
          cartesian3Scratch5
        );
        if (p0.y < 0.0) {
          Matrix2.Cartesian3.negate(offset, offset);
          p0Attributes = westGeometry.attributes;
          p0Indices = westGeometry.indices;
          p2Attributes = eastGeometry.attributes;
          p2Indices = eastGeometry.indices;
        }

        const offsetPoint = Matrix2.Cartesian3.add(
          intersection,
          offset,
          cartesian3Scratch6
        );
        p0Attributes.position.values.push(p0.x, p0.y, p0.z, p0.x, p0.y, p0.z);
        p0Attributes.position.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p0Attributes.position.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );

        p0Attributes.prevPosition.values.push(
          prevPositions[i0 * 3],
          prevPositions[i0 * 3 + 1],
          prevPositions[i0 * 3 + 2]
        );
        p0Attributes.prevPosition.values.push(
          prevPositions[i0 * 3 + 3],
          prevPositions[i0 * 3 + 4],
          prevPositions[i0 * 3 + 5]
        );
        p0Attributes.prevPosition.values.push(p0.x, p0.y, p0.z, p0.x, p0.y, p0.z);

        p0Attributes.nextPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p0Attributes.nextPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p0Attributes.nextPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p0Attributes.nextPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );

        Matrix2.Cartesian3.negate(offset, offset);
        Matrix2.Cartesian3.add(intersection, offset, offsetPoint);
        p2Attributes.position.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p2Attributes.position.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p2Attributes.position.values.push(p2.x, p2.y, p2.z, p2.x, p2.y, p2.z);

        p2Attributes.prevPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p2Attributes.prevPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p2Attributes.prevPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );
        p2Attributes.prevPosition.values.push(
          offsetPoint.x,
          offsetPoint.y,
          offsetPoint.z
        );

        p2Attributes.nextPosition.values.push(p2.x, p2.y, p2.z, p2.x, p2.y, p2.z);
        p2Attributes.nextPosition.values.push(
          nextPositions[i2 * 3],
          nextPositions[i2 * 3 + 1],
          nextPositions[i2 * 3 + 2]
        );
        p2Attributes.nextPosition.values.push(
          nextPositions[i2 * 3 + 3],
          nextPositions[i2 * 3 + 4],
          nextPositions[i2 * 3 + 5]
        );

        const ew0 = Matrix2.Cartesian2.fromArray(
          expandAndWidths,
          i0 * 2,
          cartesian2Scratch0
        );
        const width = Math.abs(ew0.y);

        p0Attributes.expandAndWidth.values.push(-1, width, 1, width);
        p0Attributes.expandAndWidth.values.push(-1, -width, 1, -width);
        p2Attributes.expandAndWidth.values.push(-1, width, 1, width);
        p2Attributes.expandAndWidth.values.push(-1, -width, 1, -width);

        let t = Matrix2.Cartesian3.magnitudeSquared(
          Matrix2.Cartesian3.subtract(intersection, p0, cartesian3Scratch3)
        );
        t /= Matrix2.Cartesian3.magnitudeSquared(
          Matrix2.Cartesian3.subtract(p2, p0, cartesian3Scratch3)
        );

        if (defaultValue.defined(colors)) {
          const c0 = Matrix2.Cartesian4.fromArray(colors, i0 * 4, cartesian4Scratch0);
          const c2 = Matrix2.Cartesian4.fromArray(colors, i2 * 4, cartesian4Scratch0);

          const r = ComponentDatatype.CesiumMath.lerp(c0.x, c2.x, t);
          const g = ComponentDatatype.CesiumMath.lerp(c0.y, c2.y, t);
          const b = ComponentDatatype.CesiumMath.lerp(c0.z, c2.z, t);
          const a = ComponentDatatype.CesiumMath.lerp(c0.w, c2.w, t);

          for (j = i0 * 4; j < i0 * 4 + 2 * 4; ++j) {
            p0Attributes.color.values.push(colors[j]);
          }
          p0Attributes.color.values.push(r, g, b, a);
          p0Attributes.color.values.push(r, g, b, a);
          p2Attributes.color.values.push(r, g, b, a);
          p2Attributes.color.values.push(r, g, b, a);
          for (j = i2 * 4; j < i2 * 4 + 2 * 4; ++j) {
            p2Attributes.color.values.push(colors[j]);
          }
        }

        if (defaultValue.defined(texCoords)) {
          const s0 = Matrix2.Cartesian2.fromArray(texCoords, i0 * 2, cartesian2Scratch0);
          const s3 = Matrix2.Cartesian2.fromArray(
            texCoords,
            (i + 3) * 2,
            cartesian2Scratch1
          );

          const sx = ComponentDatatype.CesiumMath.lerp(s0.x, s3.x, t);

          for (j = i0 * 2; j < i0 * 2 + 2 * 2; ++j) {
            p0Attributes.st.values.push(texCoords[j]);
          }
          p0Attributes.st.values.push(sx, s0.y);
          p0Attributes.st.values.push(sx, s3.y);
          p2Attributes.st.values.push(sx, s0.y);
          p2Attributes.st.values.push(sx, s3.y);
          for (j = i2 * 2; j < i2 * 2 + 2 * 2; ++j) {
            p2Attributes.st.values.push(texCoords[j]);
          }
        }

        index = p0Attributes.position.values.length / 3 - 4;
        p0Indices.push(index, index + 2, index + 1);
        p0Indices.push(index + 1, index + 2, index + 3);

        index = p2Attributes.position.values.length / 3 - 4;
        p2Indices.push(index, index + 2, index + 1);
        p2Indices.push(index + 1, index + 2, index + 3);
      } else {
        let currentAttributes;
        let currentIndices;

        if (p0.y < 0.0) {
          currentAttributes = westGeometry.attributes;
          currentIndices = westGeometry.indices;
        } else {
          currentAttributes = eastGeometry.attributes;
          currentIndices = eastGeometry.indices;
        }

        currentAttributes.position.values.push(p0.x, p0.y, p0.z);
        currentAttributes.position.values.push(p0.x, p0.y, p0.z);
        currentAttributes.position.values.push(p2.x, p2.y, p2.z);
        currentAttributes.position.values.push(p2.x, p2.y, p2.z);

        for (j = i * 3; j < i * 3 + 4 * 3; ++j) {
          currentAttributes.prevPosition.values.push(prevPositions[j]);
          currentAttributes.nextPosition.values.push(nextPositions[j]);
        }

        for (j = i * 2; j < i * 2 + 4 * 2; ++j) {
          currentAttributes.expandAndWidth.values.push(expandAndWidths[j]);
          if (defaultValue.defined(texCoords)) {
            currentAttributes.st.values.push(texCoords[j]);
          }
        }

        if (defaultValue.defined(colors)) {
          for (j = i * 4; j < i * 4 + 4 * 4; ++j) {
            currentAttributes.color.values.push(colors[j]);
          }
        }

        index = currentAttributes.position.values.length / 3 - 4;
        currentIndices.push(index, index + 2, index + 1);
        currentIndices.push(index + 1, index + 2, index + 3);
      }
    }

    if (intersectionFound) {
      updateAdjacencyAfterSplit(westGeometry);
      updateAdjacencyAfterSplit(eastGeometry);
    }

    updateInstanceAfterSplit(instance, westGeometry, eastGeometry);
  }

  /**
   * Splits the instances's geometry, by introducing new vertices and indices,that
   * intersect the International Date Line and Prime Meridian so that no primitives cross longitude
   * -180/180 degrees.  This is not required for 3D drawing, but is required for
   * correcting drawing in 2D and Columbus view.
   *
   * @private
   *
   * @param {GeometryInstance} instance The instance to modify.
   * @returns {GeometryInstance} The modified <code>instance</code> argument, with it's geometry split at the International Date Line.
   *
   * @example
   * instance = Cesium.GeometryPipeline.splitLongitude(instance);
   */
  GeometryPipeline.splitLongitude = function (instance) {
    //>>includeStart('debug', pragmas.debug);
    if (!defaultValue.defined(instance)) {
      throw new RuntimeError.DeveloperError("instance is required.");
    }
    //>>includeEnd('debug');

    const geometry = instance.geometry;
    const boundingSphere = geometry.boundingSphere;
    if (defaultValue.defined(boundingSphere)) {
      const minX = boundingSphere.center.x - boundingSphere.radius;
      if (
        minX > 0 ||
        Transforms.BoundingSphere.intersectPlane(boundingSphere, Plane.Plane.ORIGIN_ZX_PLANE) !==
          Transforms.Intersect.INTERSECTING
      ) {
        return instance;
      }
    }

    if (geometry.geometryType !== GeometryAttribute.GeometryType.NONE) {
      switch (geometry.geometryType) {
        case GeometryAttribute.GeometryType.POLYLINES:
          splitLongitudePolyline(instance);
          break;
        case GeometryAttribute.GeometryType.TRIANGLES:
          splitLongitudeTriangles(instance);
          break;
        case GeometryAttribute.GeometryType.LINES:
          splitLongitudeLines(instance);
          break;
      }
    } else {
      indexPrimitive(geometry);
      if (geometry.primitiveType === GeometryAttribute.PrimitiveType.TRIANGLES) {
        splitLongitudeTriangles(instance);
      } else if (geometry.primitiveType === GeometryAttribute.PrimitiveType.LINES) {
        splitLongitudeLines(instance);
      }
    }

    return instance;
  };

  exports.GeometryPipeline = GeometryPipeline;

}));