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casic-smartcity-well-front / static / Cesium / Core / BoxGeometry.js
[wangxitong] on 8 Jul 2021 23 KB mars3d总览
import arrayFill from "./arrayFill.js";
import BoundingSphere from "./BoundingSphere.js";
import Cartesian3 from "./Cartesian3.js";
import Check from "./Check.js";
import ComponentDatatype from "./ComponentDatatype.js";
import defaultValue from "./defaultValue.js";
import defined from "./defined.js";
import DeveloperError from "./DeveloperError.js";
import Geometry from "./Geometry.js";
import GeometryAttribute from "./GeometryAttribute.js";
import GeometryAttributes from "./GeometryAttributes.js";
import GeometryOffsetAttribute from "./GeometryOffsetAttribute.js";
import PrimitiveType from "./PrimitiveType.js";
import VertexFormat from "./VertexFormat.js";

var diffScratch = new Cartesian3();

/**
 * Describes a cube centered at the origin.
 *
 * @alias BoxGeometry
 * @constructor
 *
 * @param {Object} options Object with the following properties:
 * @param {Cartesian3} options.minimum The minimum x, y, and z coordinates of the box.
 * @param {Cartesian3} options.maximum The maximum x, y, and z coordinates of the box.
 * @param {VertexFormat} [options.vertexFormat=VertexFormat.DEFAULT] The vertex attributes to be computed.
 *
 * @see BoxGeometry.fromDimensions
 * @see BoxGeometry.createGeometry
 * @see Packable
 *
 * @demo {@link https://sandcastle.cesium.com/index.html?src=Box.html|Cesium Sandcastle Box Demo}
 *
 * @example
 * var box = new Cesium.BoxGeometry({
 *   vertexFormat : Cesium.VertexFormat.POSITION_ONLY,
 *   maximum : new Cesium.Cartesian3(250000.0, 250000.0, 250000.0),
 *   minimum : new Cesium.Cartesian3(-250000.0, -250000.0, -250000.0)
 * });
 * var geometry = Cesium.BoxGeometry.createGeometry(box);
 */
function BoxGeometry(options) {
  options = defaultValue(options, defaultValue.EMPTY_OBJECT);

  var min = options.minimum;
  var max = options.maximum;

  //>>includeStart('debug', pragmas.debug);
  Check.typeOf.object("min", min);
  Check.typeOf.object("max", max);
  if (
    defined(options.offsetAttribute) &&
    options.offsetAttribute === GeometryOffsetAttribute.TOP
  ) {
    throw new DeveloperError(
      "GeometryOffsetAttribute.TOP is not a supported options.offsetAttribute for this geometry."
    );
  }
  //>>includeEnd('debug');

  var vertexFormat = defaultValue(options.vertexFormat, VertexFormat.DEFAULT);

  this._minimum = Cartesian3.clone(min);
  this._maximum = Cartesian3.clone(max);
  this._vertexFormat = vertexFormat;
  this._offsetAttribute = options.offsetAttribute;
  this._workerName = "createBoxGeometry";
}

/**
 * Creates a cube centered at the origin given its dimensions.
 *
 * @param {Object} options Object with the following properties:
 * @param {Cartesian3} options.dimensions The width, depth, and height of the box stored in the x, y, and z coordinates of the <code>Cartesian3</code>, respectively.
 * @param {VertexFormat} [options.vertexFormat=VertexFormat.DEFAULT] The vertex attributes to be computed.
 * @returns {BoxGeometry}
 *
 * @exception {DeveloperError} All dimensions components must be greater than or equal to zero.
 *
 *
 * @example
 * var box = Cesium.BoxGeometry.fromDimensions({
 *   vertexFormat : Cesium.VertexFormat.POSITION_ONLY,
 *   dimensions : new Cesium.Cartesian3(500000.0, 500000.0, 500000.0)
 * });
 * var geometry = Cesium.BoxGeometry.createGeometry(box);
 *
 * @see BoxGeometry.createGeometry
 */
BoxGeometry.fromDimensions = function (options) {
  options = defaultValue(options, defaultValue.EMPTY_OBJECT);
  var dimensions = options.dimensions;

  //>>includeStart('debug', pragmas.debug);
  Check.typeOf.object("dimensions", dimensions);
  Check.typeOf.number.greaterThanOrEquals("dimensions.x", dimensions.x, 0);
  Check.typeOf.number.greaterThanOrEquals("dimensions.y", dimensions.y, 0);
  Check.typeOf.number.greaterThanOrEquals("dimensions.z", dimensions.z, 0);
  //>>includeEnd('debug');

  var corner = Cartesian3.multiplyByScalar(dimensions, 0.5, new Cartesian3());

  return new BoxGeometry({
    minimum: Cartesian3.negate(corner, new Cartesian3()),
    maximum: corner,
    vertexFormat: options.vertexFormat,
    offsetAttribute: options.offsetAttribute,
  });
};

/**
 * Creates a cube from the dimensions of an AxisAlignedBoundingBox.
 *
 * @param {AxisAlignedBoundingBox} boundingBox A description of the AxisAlignedBoundingBox.
 * @returns {BoxGeometry}
 *
 *
 *
 * @example
 * var aabb = Cesium.AxisAlignedBoundingBox.fromPoints(Cesium.Cartesian3.fromDegreesArray([
 *      -72.0, 40.0,
 *      -70.0, 35.0,
 *      -75.0, 30.0,
 *      -70.0, 30.0,
 *      -68.0, 40.0
 * ]));
 * var box = Cesium.BoxGeometry.fromAxisAlignedBoundingBox(aabb);
 *
 * @see BoxGeometry.createGeometry
 */
BoxGeometry.fromAxisAlignedBoundingBox = function (boundingBox) {
  //>>includeStart('debug', pragmas.debug);
  Check.typeOf.object("boundingBox", boundingBox);
  //>>includeEnd('debug');

  return new BoxGeometry({
    minimum: boundingBox.minimum,
    maximum: boundingBox.maximum,
  });
};

/**
 * The number of elements used to pack the object into an array.
 * @type {Number}
 */
BoxGeometry.packedLength =
  2 * Cartesian3.packedLength + VertexFormat.packedLength + 1;

/**
 * Stores the provided instance into the provided array.
 *
 * @param {BoxGeometry} value The value to pack.
 * @param {Number[]} array The array to pack into.
 * @param {Number} [startingIndex=0] The index into the array at which to start packing the elements.
 *
 * @returns {Number[]} The array that was packed into
 */
BoxGeometry.pack = function (value, array, startingIndex) {
  //>>includeStart('debug', pragmas.debug);
  Check.typeOf.object("value", value);
  Check.defined("array", array);
  //>>includeEnd('debug');

  startingIndex = defaultValue(startingIndex, 0);

  Cartesian3.pack(value._minimum, array, startingIndex);
  Cartesian3.pack(
    value._maximum,
    array,
    startingIndex + Cartesian3.packedLength
  );
  VertexFormat.pack(
    value._vertexFormat,
    array,
    startingIndex + 2 * Cartesian3.packedLength
  );
  array[
    startingIndex + 2 * Cartesian3.packedLength + VertexFormat.packedLength
  ] = defaultValue(value._offsetAttribute, -1);

  return array;
};

var scratchMin = new Cartesian3();
var scratchMax = new Cartesian3();
var scratchVertexFormat = new VertexFormat();
var scratchOptions = {
  minimum: scratchMin,
  maximum: scratchMax,
  vertexFormat: scratchVertexFormat,
  offsetAttribute: undefined,
};

/**
 * Retrieves an instance from a packed array.
 *
 * @param {Number[]} array The packed array.
 * @param {Number} [startingIndex=0] The starting index of the element to be unpacked.
 * @param {BoxGeometry} [result] The object into which to store the result.
 * @returns {BoxGeometry} The modified result parameter or a new BoxGeometry instance if one was not provided.
 */
BoxGeometry.unpack = function (array, startingIndex, result) {
  //>>includeStart('debug', pragmas.debug);
  Check.defined("array", array);
  //>>includeEnd('debug');

  startingIndex = defaultValue(startingIndex, 0);

  var min = Cartesian3.unpack(array, startingIndex, scratchMin);
  var max = Cartesian3.unpack(
    array,
    startingIndex + Cartesian3.packedLength,
    scratchMax
  );
  var vertexFormat = VertexFormat.unpack(
    array,
    startingIndex + 2 * Cartesian3.packedLength,
    scratchVertexFormat
  );
  var offsetAttribute =
    array[
      startingIndex + 2 * Cartesian3.packedLength + VertexFormat.packedLength
    ];

  if (!defined(result)) {
    scratchOptions.offsetAttribute =
      offsetAttribute === -1 ? undefined : offsetAttribute;
    return new BoxGeometry(scratchOptions);
  }

  result._minimum = Cartesian3.clone(min, result._minimum);
  result._maximum = Cartesian3.clone(max, result._maximum);
  result._vertexFormat = VertexFormat.clone(vertexFormat, result._vertexFormat);
  result._offsetAttribute =
    offsetAttribute === -1 ? undefined : offsetAttribute;

  return result;
};

/**
 * Computes the geometric representation of a box, including its vertices, indices, and a bounding sphere.
 *
 * @param {BoxGeometry} boxGeometry A description of the box.
 * @returns {Geometry|undefined} The computed vertices and indices.
 */
BoxGeometry.createGeometry = function (boxGeometry) {
  var min = boxGeometry._minimum;
  var max = boxGeometry._maximum;
  var vertexFormat = boxGeometry._vertexFormat;

  if (Cartesian3.equals(min, max)) {
    return;
  }

  var attributes = new GeometryAttributes();
  var indices;
  var positions;

  if (
    vertexFormat.position &&
    (vertexFormat.st ||
      vertexFormat.normal ||
      vertexFormat.tangent ||
      vertexFormat.bitangent)
  ) {
    if (vertexFormat.position) {
      // 8 corner points.  Duplicated 3 times each for each incident edge/face.
      positions = new Float64Array(6 * 4 * 3);

      // +z face
      positions[0] = min.x;
      positions[1] = min.y;
      positions[2] = max.z;
      positions[3] = max.x;
      positions[4] = min.y;
      positions[5] = max.z;
      positions[6] = max.x;
      positions[7] = max.y;
      positions[8] = max.z;
      positions[9] = min.x;
      positions[10] = max.y;
      positions[11] = max.z;

      // -z face
      positions[12] = min.x;
      positions[13] = min.y;
      positions[14] = min.z;
      positions[15] = max.x;
      positions[16] = min.y;
      positions[17] = min.z;
      positions[18] = max.x;
      positions[19] = max.y;
      positions[20] = min.z;
      positions[21] = min.x;
      positions[22] = max.y;
      positions[23] = min.z;

      // +x face
      positions[24] = max.x;
      positions[25] = min.y;
      positions[26] = min.z;
      positions[27] = max.x;
      positions[28] = max.y;
      positions[29] = min.z;
      positions[30] = max.x;
      positions[31] = max.y;
      positions[32] = max.z;
      positions[33] = max.x;
      positions[34] = min.y;
      positions[35] = max.z;

      // -x face
      positions[36] = min.x;
      positions[37] = min.y;
      positions[38] = min.z;
      positions[39] = min.x;
      positions[40] = max.y;
      positions[41] = min.z;
      positions[42] = min.x;
      positions[43] = max.y;
      positions[44] = max.z;
      positions[45] = min.x;
      positions[46] = min.y;
      positions[47] = max.z;

      // +y face
      positions[48] = min.x;
      positions[49] = max.y;
      positions[50] = min.z;
      positions[51] = max.x;
      positions[52] = max.y;
      positions[53] = min.z;
      positions[54] = max.x;
      positions[55] = max.y;
      positions[56] = max.z;
      positions[57] = min.x;
      positions[58] = max.y;
      positions[59] = max.z;

      // -y face
      positions[60] = min.x;
      positions[61] = min.y;
      positions[62] = min.z;
      positions[63] = max.x;
      positions[64] = min.y;
      positions[65] = min.z;
      positions[66] = max.x;
      positions[67] = min.y;
      positions[68] = max.z;
      positions[69] = min.x;
      positions[70] = min.y;
      positions[71] = max.z;

      attributes.position = new GeometryAttribute({
        componentDatatype: ComponentDatatype.DOUBLE,
        componentsPerAttribute: 3,
        values: positions,
      });
    }

    if (vertexFormat.normal) {
      var normals = new Float32Array(6 * 4 * 3);

      // +z face
      normals[0] = 0.0;
      normals[1] = 0.0;
      normals[2] = 1.0;
      normals[3] = 0.0;
      normals[4] = 0.0;
      normals[5] = 1.0;
      normals[6] = 0.0;
      normals[7] = 0.0;
      normals[8] = 1.0;
      normals[9] = 0.0;
      normals[10] = 0.0;
      normals[11] = 1.0;

      // -z face
      normals[12] = 0.0;
      normals[13] = 0.0;
      normals[14] = -1.0;
      normals[15] = 0.0;
      normals[16] = 0.0;
      normals[17] = -1.0;
      normals[18] = 0.0;
      normals[19] = 0.0;
      normals[20] = -1.0;
      normals[21] = 0.0;
      normals[22] = 0.0;
      normals[23] = -1.0;

      // +x face
      normals[24] = 1.0;
      normals[25] = 0.0;
      normals[26] = 0.0;
      normals[27] = 1.0;
      normals[28] = 0.0;
      normals[29] = 0.0;
      normals[30] = 1.0;
      normals[31] = 0.0;
      normals[32] = 0.0;
      normals[33] = 1.0;
      normals[34] = 0.0;
      normals[35] = 0.0;

      // -x face
      normals[36] = -1.0;
      normals[37] = 0.0;
      normals[38] = 0.0;
      normals[39] = -1.0;
      normals[40] = 0.0;
      normals[41] = 0.0;
      normals[42] = -1.0;
      normals[43] = 0.0;
      normals[44] = 0.0;
      normals[45] = -1.0;
      normals[46] = 0.0;
      normals[47] = 0.0;

      // +y face
      normals[48] = 0.0;
      normals[49] = 1.0;
      normals[50] = 0.0;
      normals[51] = 0.0;
      normals[52] = 1.0;
      normals[53] = 0.0;
      normals[54] = 0.0;
      normals[55] = 1.0;
      normals[56] = 0.0;
      normals[57] = 0.0;
      normals[58] = 1.0;
      normals[59] = 0.0;

      // -y face
      normals[60] = 0.0;
      normals[61] = -1.0;
      normals[62] = 0.0;
      normals[63] = 0.0;
      normals[64] = -1.0;
      normals[65] = 0.0;
      normals[66] = 0.0;
      normals[67] = -1.0;
      normals[68] = 0.0;
      normals[69] = 0.0;
      normals[70] = -1.0;
      normals[71] = 0.0;

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

    if (vertexFormat.st) {
      var texCoords = new Float32Array(6 * 4 * 2);

      // +z face
      texCoords[0] = 0.0;
      texCoords[1] = 0.0;
      texCoords[2] = 1.0;
      texCoords[3] = 0.0;
      texCoords[4] = 1.0;
      texCoords[5] = 1.0;
      texCoords[6] = 0.0;
      texCoords[7] = 1.0;

      // -z face
      texCoords[8] = 1.0;
      texCoords[9] = 0.0;
      texCoords[10] = 0.0;
      texCoords[11] = 0.0;
      texCoords[12] = 0.0;
      texCoords[13] = 1.0;
      texCoords[14] = 1.0;
      texCoords[15] = 1.0;

      //+x face
      texCoords[16] = 0.0;
      texCoords[17] = 0.0;
      texCoords[18] = 1.0;
      texCoords[19] = 0.0;
      texCoords[20] = 1.0;
      texCoords[21] = 1.0;
      texCoords[22] = 0.0;
      texCoords[23] = 1.0;

      // -x face
      texCoords[24] = 1.0;
      texCoords[25] = 0.0;
      texCoords[26] = 0.0;
      texCoords[27] = 0.0;
      texCoords[28] = 0.0;
      texCoords[29] = 1.0;
      texCoords[30] = 1.0;
      texCoords[31] = 1.0;

      // +y face
      texCoords[32] = 1.0;
      texCoords[33] = 0.0;
      texCoords[34] = 0.0;
      texCoords[35] = 0.0;
      texCoords[36] = 0.0;
      texCoords[37] = 1.0;
      texCoords[38] = 1.0;
      texCoords[39] = 1.0;

      // -y face
      texCoords[40] = 0.0;
      texCoords[41] = 0.0;
      texCoords[42] = 1.0;
      texCoords[43] = 0.0;
      texCoords[44] = 1.0;
      texCoords[45] = 1.0;
      texCoords[46] = 0.0;
      texCoords[47] = 1.0;

      attributes.st = new GeometryAttribute({
        componentDatatype: ComponentDatatype.FLOAT,
        componentsPerAttribute: 2,
        values: texCoords,
      });
    }

    if (vertexFormat.tangent) {
      var tangents = new Float32Array(6 * 4 * 3);

      // +z face
      tangents[0] = 1.0;
      tangents[1] = 0.0;
      tangents[2] = 0.0;
      tangents[3] = 1.0;
      tangents[4] = 0.0;
      tangents[5] = 0.0;
      tangents[6] = 1.0;
      tangents[7] = 0.0;
      tangents[8] = 0.0;
      tangents[9] = 1.0;
      tangents[10] = 0.0;
      tangents[11] = 0.0;

      // -z face
      tangents[12] = -1.0;
      tangents[13] = 0.0;
      tangents[14] = 0.0;
      tangents[15] = -1.0;
      tangents[16] = 0.0;
      tangents[17] = 0.0;
      tangents[18] = -1.0;
      tangents[19] = 0.0;
      tangents[20] = 0.0;
      tangents[21] = -1.0;
      tangents[22] = 0.0;
      tangents[23] = 0.0;

      // +x face
      tangents[24] = 0.0;
      tangents[25] = 1.0;
      tangents[26] = 0.0;
      tangents[27] = 0.0;
      tangents[28] = 1.0;
      tangents[29] = 0.0;
      tangents[30] = 0.0;
      tangents[31] = 1.0;
      tangents[32] = 0.0;
      tangents[33] = 0.0;
      tangents[34] = 1.0;
      tangents[35] = 0.0;

      // -x face
      tangents[36] = 0.0;
      tangents[37] = -1.0;
      tangents[38] = 0.0;
      tangents[39] = 0.0;
      tangents[40] = -1.0;
      tangents[41] = 0.0;
      tangents[42] = 0.0;
      tangents[43] = -1.0;
      tangents[44] = 0.0;
      tangents[45] = 0.0;
      tangents[46] = -1.0;
      tangents[47] = 0.0;

      // +y face
      tangents[48] = -1.0;
      tangents[49] = 0.0;
      tangents[50] = 0.0;
      tangents[51] = -1.0;
      tangents[52] = 0.0;
      tangents[53] = 0.0;
      tangents[54] = -1.0;
      tangents[55] = 0.0;
      tangents[56] = 0.0;
      tangents[57] = -1.0;
      tangents[58] = 0.0;
      tangents[59] = 0.0;

      // -y face
      tangents[60] = 1.0;
      tangents[61] = 0.0;
      tangents[62] = 0.0;
      tangents[63] = 1.0;
      tangents[64] = 0.0;
      tangents[65] = 0.0;
      tangents[66] = 1.0;
      tangents[67] = 0.0;
      tangents[68] = 0.0;
      tangents[69] = 1.0;
      tangents[70] = 0.0;
      tangents[71] = 0.0;

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

    if (vertexFormat.bitangent) {
      var bitangents = new Float32Array(6 * 4 * 3);

      // +z face
      bitangents[0] = 0.0;
      bitangents[1] = 1.0;
      bitangents[2] = 0.0;
      bitangents[3] = 0.0;
      bitangents[4] = 1.0;
      bitangents[5] = 0.0;
      bitangents[6] = 0.0;
      bitangents[7] = 1.0;
      bitangents[8] = 0.0;
      bitangents[9] = 0.0;
      bitangents[10] = 1.0;
      bitangents[11] = 0.0;

      // -z face
      bitangents[12] = 0.0;
      bitangents[13] = 1.0;
      bitangents[14] = 0.0;
      bitangents[15] = 0.0;
      bitangents[16] = 1.0;
      bitangents[17] = 0.0;
      bitangents[18] = 0.0;
      bitangents[19] = 1.0;
      bitangents[20] = 0.0;
      bitangents[21] = 0.0;
      bitangents[22] = 1.0;
      bitangents[23] = 0.0;

      // +x face
      bitangents[24] = 0.0;
      bitangents[25] = 0.0;
      bitangents[26] = 1.0;
      bitangents[27] = 0.0;
      bitangents[28] = 0.0;
      bitangents[29] = 1.0;
      bitangents[30] = 0.0;
      bitangents[31] = 0.0;
      bitangents[32] = 1.0;
      bitangents[33] = 0.0;
      bitangents[34] = 0.0;
      bitangents[35] = 1.0;

      // -x face
      bitangents[36] = 0.0;
      bitangents[37] = 0.0;
      bitangents[38] = 1.0;
      bitangents[39] = 0.0;
      bitangents[40] = 0.0;
      bitangents[41] = 1.0;
      bitangents[42] = 0.0;
      bitangents[43] = 0.0;
      bitangents[44] = 1.0;
      bitangents[45] = 0.0;
      bitangents[46] = 0.0;
      bitangents[47] = 1.0;

      // +y face
      bitangents[48] = 0.0;
      bitangents[49] = 0.0;
      bitangents[50] = 1.0;
      bitangents[51] = 0.0;
      bitangents[52] = 0.0;
      bitangents[53] = 1.0;
      bitangents[54] = 0.0;
      bitangents[55] = 0.0;
      bitangents[56] = 1.0;
      bitangents[57] = 0.0;
      bitangents[58] = 0.0;
      bitangents[59] = 1.0;

      // -y face
      bitangents[60] = 0.0;
      bitangents[61] = 0.0;
      bitangents[62] = 1.0;
      bitangents[63] = 0.0;
      bitangents[64] = 0.0;
      bitangents[65] = 1.0;
      bitangents[66] = 0.0;
      bitangents[67] = 0.0;
      bitangents[68] = 1.0;
      bitangents[69] = 0.0;
      bitangents[70] = 0.0;
      bitangents[71] = 1.0;

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

    // 12 triangles:  6 faces, 2 triangles each.
    indices = new Uint16Array(6 * 2 * 3);

    // +z face
    indices[0] = 0;
    indices[1] = 1;
    indices[2] = 2;
    indices[3] = 0;
    indices[4] = 2;
    indices[5] = 3;

    // -z face
    indices[6] = 4 + 2;
    indices[7] = 4 + 1;
    indices[8] = 4 + 0;
    indices[9] = 4 + 3;
    indices[10] = 4 + 2;
    indices[11] = 4 + 0;

    // +x face
    indices[12] = 8 + 0;
    indices[13] = 8 + 1;
    indices[14] = 8 + 2;
    indices[15] = 8 + 0;
    indices[16] = 8 + 2;
    indices[17] = 8 + 3;

    // -x face
    indices[18] = 12 + 2;
    indices[19] = 12 + 1;
    indices[20] = 12 + 0;
    indices[21] = 12 + 3;
    indices[22] = 12 + 2;
    indices[23] = 12 + 0;

    // +y face
    indices[24] = 16 + 2;
    indices[25] = 16 + 1;
    indices[26] = 16 + 0;
    indices[27] = 16 + 3;
    indices[28] = 16 + 2;
    indices[29] = 16 + 0;

    // -y face
    indices[30] = 20 + 0;
    indices[31] = 20 + 1;
    indices[32] = 20 + 2;
    indices[33] = 20 + 0;
    indices[34] = 20 + 2;
    indices[35] = 20 + 3;
  } else {
    // Positions only - no need to duplicate corner points
    positions = new Float64Array(8 * 3);

    positions[0] = min.x;
    positions[1] = min.y;
    positions[2] = min.z;
    positions[3] = max.x;
    positions[4] = min.y;
    positions[5] = min.z;
    positions[6] = max.x;
    positions[7] = max.y;
    positions[8] = min.z;
    positions[9] = min.x;
    positions[10] = max.y;
    positions[11] = min.z;
    positions[12] = min.x;
    positions[13] = min.y;
    positions[14] = max.z;
    positions[15] = max.x;
    positions[16] = min.y;
    positions[17] = max.z;
    positions[18] = max.x;
    positions[19] = max.y;
    positions[20] = max.z;
    positions[21] = min.x;
    positions[22] = max.y;
    positions[23] = max.z;

    attributes.position = new GeometryAttribute({
      componentDatatype: ComponentDatatype.DOUBLE,
      componentsPerAttribute: 3,
      values: positions,
    });

    // 12 triangles:  6 faces, 2 triangles each.
    indices = new Uint16Array(6 * 2 * 3);

    // plane z = corner.Z
    indices[0] = 4;
    indices[1] = 5;
    indices[2] = 6;
    indices[3] = 4;
    indices[4] = 6;
    indices[5] = 7;

    // plane z = -corner.Z
    indices[6] = 1;
    indices[7] = 0;
    indices[8] = 3;
    indices[9] = 1;
    indices[10] = 3;
    indices[11] = 2;

    // plane x = corner.X
    indices[12] = 1;
    indices[13] = 6;
    indices[14] = 5;
    indices[15] = 1;
    indices[16] = 2;
    indices[17] = 6;

    // plane y = corner.Y
    indices[18] = 2;
    indices[19] = 3;
    indices[20] = 7;
    indices[21] = 2;
    indices[22] = 7;
    indices[23] = 6;

    // plane x = -corner.X
    indices[24] = 3;
    indices[25] = 0;
    indices[26] = 4;
    indices[27] = 3;
    indices[28] = 4;
    indices[29] = 7;

    // plane y = -corner.Y
    indices[30] = 0;
    indices[31] = 1;
    indices[32] = 5;
    indices[33] = 0;
    indices[34] = 5;
    indices[35] = 4;
  }

  var diff = Cartesian3.subtract(max, min, diffScratch);
  var radius = Cartesian3.magnitude(diff) * 0.5;

  if (defined(boxGeometry._offsetAttribute)) {
    var length = positions.length;
    var applyOffset = new Uint8Array(length / 3);
    var offsetValue =
      boxGeometry._offsetAttribute === GeometryOffsetAttribute.NONE ? 0 : 1;
    arrayFill(applyOffset, offsetValue);
    attributes.applyOffset = new GeometryAttribute({
      componentDatatype: ComponentDatatype.UNSIGNED_BYTE,
      componentsPerAttribute: 1,
      values: applyOffset,
    });
  }

  return new Geometry({
    attributes: attributes,
    indices: indices,
    primitiveType: PrimitiveType.TRIANGLES,
    boundingSphere: new BoundingSphere(Cartesian3.ZERO, radius),
    offsetAttribute: boxGeometry._offsetAttribute,
  });
};

var unitBoxGeometry;

/**
 * Returns the geometric representation of a unit box, including its vertices, indices, and a bounding sphere.
 * @returns {Geometry} The computed vertices and indices.
 *
 * @private
 */
BoxGeometry.getUnitBox = function () {
  if (!defined(unitBoxGeometry)) {
    unitBoxGeometry = BoxGeometry.createGeometry(
      BoxGeometry.fromDimensions({
        dimensions: new Cartesian3(1.0, 1.0, 1.0),
        vertexFormat: VertexFormat.POSITION_ONLY,
      })
    );
  }
  return unitBoxGeometry;
};
export default BoxGeometry;