text: /**
   * @license
   * Copyright The Closure Library Authors.
   * SPDX-License-Identifier: Apache-2.0
   */
  
  /**
   * @fileoverview A utility class for representing three-dimensional points.
   *
   * Based heavily on coordinate.js by:
   */
  
  goog.provide('goog.math.Coordinate3');
  
  
  
  /**
   * Class for representing coordinates and positions in 3 dimensions.
   *
   * @param {number=} opt_x X coordinate, defaults to 0.
   * @param {number=} opt_y Y coordinate, defaults to 0.
   * @param {number=} opt_z Z coordinate, defaults to 0.
   * @struct
   * @constructor
   */
  goog.math.Coordinate3 = function(opt_x, opt_y, opt_z) {
    /**
     * X-value
     * @type {number}
     */
    this.x = (opt_x !== undefined) ? opt_x : 0;
  
    /**
     * Y-value
     * @type {number}
     */
    this.y = (opt_y !== undefined) ? opt_y : 0;
  
    /**
     * Z-value
     * @type {number}
     */
    this.z = (opt_z !== undefined) ? opt_z : 0;
  };
  
  
  /**
   * Returns a new copy of the coordinate.
   *
   * @return {!goog.math.Coordinate3} A clone of this coordinate.
   */
  goog.math.Coordinate3.prototype.clone = function() {
    return new goog.math.Coordinate3(this.x, this.y, this.z);
  };
  
  
  if (goog.DEBUG) {
    /**
     * Returns a nice string representing the coordinate.
     *
     * @return {string} In the form (50, 73, 31).
     * @override
     */
    goog.math.Coordinate3.prototype.toString = function() {
      return '(' + this.x + ', ' + this.y + ', ' + this.z + ')';
    };
  }
  
  
  /**
   * Compares coordinates for equality.
   *
   * @param {goog.math.Coordinate3} a A Coordinate3.
   * @param {goog.math.Coordinate3} b A Coordinate3.
   * @return {boolean} True iff the coordinates are equal, or if both are null.
   */
  goog.math.Coordinate3.equals = function(a, b) {
    if (a == b) {
      return true;
    }
    if (!a || !b) {
      return false;
    }
    return a.x == b.x && a.y == b.y && a.z == b.z;
  };
  
  
  /**
   * Returns the distance between two coordinates.
   *
   * @param {goog.math.Coordinate3} a A Coordinate3.
   * @param {goog.math.Coordinate3} b A Coordinate3.
   * @return {number} The distance between `a` and `b`.
   */
  goog.math.Coordinate3.distance = function(a, b) {
    const dx = a.x - b.x;
    const dy = a.y - b.y;
    const dz = a.z - b.z;
    return Math.sqrt(dx * dx + dy * dy + dz * dz);
  };
  
  
  /**
   * Returns the squared distance between two coordinates. Squared distances can
   * be used for comparisons when the actual value is not required.
   *
   * Performance note: eliminating the square root is an optimization often used
   * in lower-level languages, but the speed difference is not nearly as
   * pronounced in JavaScript (only a few percent.)
   *
   * @param {goog.math.Coordinate3} a A Coordinate3.
   * @param {goog.math.Coordinate3} b A Coordinate3.
   * @return {number} The squared distance between `a` and `b`.
   */
  goog.math.Coordinate3.squaredDistance = function(a, b) {
    const dx = a.x - b.x;
    const dy = a.y - b.y;
    const dz = a.z - b.z;
    return dx * dx + dy * dy + dz * dz;
  };
  
  
  /**
   * Returns the difference between two coordinates as a new
   * goog.math.Coordinate3.
   *
   * @param {goog.math.Coordinate3} a A Coordinate3.
   * @param {goog.math.Coordinate3} b A Coordinate3.
   * @return {!goog.math.Coordinate3} A Coordinate3 representing the difference
   *     between `a` and `b`.
   */
  goog.math.Coordinate3.difference = function(a, b) {
    return new goog.math.Coordinate3(a.x - b.x, a.y - b.y, a.z - b.z);
  };
  
  
  /**
   * Returns the contents of this coordinate as a 3 value Array.
   *
   * @return {!Array<number>} A new array.
   */
  goog.math.Coordinate3.prototype.toArray = function() {
    return [this.x, this.y, this.z];
  };
  
  
  /**
   * Converts a three element array into a Coordinate3 object.  If the value
   * passed in is not an array, not array-like, or not of the right length, an
   * error is thrown.
   *
   * @param {Array<number>} a Array of numbers to become a coordinate.
   * @return {!goog.math.Coordinate3} A new coordinate from the array values.
   * @throws {Error} When the oject passed in is not valid.
   */
  goog.math.Coordinate3.fromArray = function(a) {
    if (a.length <= 3) {
      return new goog.math.Coordinate3(a[0], a[1], a[2]);
    }
  
    throw new Error('Conversion from an array requires an array of length 3');
  };
  