Math/SphericalCoords.js

  1. /** A class representing spherical coordinates. */
  2. Lore.SphericalCoords = class SphericalCoords {
  3.     /**
  4.      * Creates an instance of SphericalCoords.
  5.      * @param {Number} radius The radius.
  6.      * @param {Number} phi Phi in radians.
  7.      * @param {Number} theta Theta in radians.
  8.      */
  9.     constructor(radius, phi, theta) {
  10.         this.components = new Float32Array(3);
  11.         this.radius = (radius !== undefined) ? radius : 1.0;
  12.         this.phi = phi ? phi : 0.0;
  13.         this.theta = theta ? theta : 0.0;
  14.     }
  16.     /**
  17.      * Set the spherical coordinates from the radius, the phi angle and the theta angle.
  18.      * 
  19.      * @param {Number} radius 
  20.      * @param {Number} phi 
  21.      * @param {Number} theta 
  22.      * @returns {SphericalCoords} Returns itself.
  23.      */
  24.     set(radius, phi, theta) {
  25.         this.components[0] = radius;
  26.         this.components[1] = phi;
  27.         this.components[2] = theta;
  29.         return this;
  30.     }
  32.     /**
  33.      * Avoid overflows.
  34.      * 
  35.      * @returns {SphericalCoords} Returns itself.
  36.      */
  37.     secure() {
  38.         this.components[1] = Math.max(0.000001, Math.min(Math.PI - 0.000001, this.components[1]));
  40.         return this;
  41.     }
  43.     /**
  44.      * Set the spherical coordaintes from a vector.
  45.      * 
  46.      * @param {Vector3f} v A vector.
  47.      * @returns {SphericalCoords} Returns itself.
  48.      */
  49.     setFromVector(v) {
  50.         this.components[0] = v.length();
  52.         if (this.components[0] === 0.0) {
  53.             this.components[1] = 0.0;
  54.             this.components[2] = 0.0;
  55.         } else {
  56.             this.components[1] = Math.acos(Math.max(-1.0, Math.min(1.0, v.components[1] /
  57.                 this.components[0])));
  58.             this.components[2] = Math.atan2(v.components[0], v.components[2]);
  59.         }
  61.         return this;
  62.     }
  64.     /**
  65.      * Limit the rotation by setting maxima and minima for phi and theta.
  66.      * 
  67.      * @param {Number} phiMin The minimum for phi.
  68.      * @param {Number} phiMax The maximum for phi.
  69.      * @param {Number} thetaMin The minimum for theta.
  70.      * @param {Number} thetaMax The maximum for theta.
  71.      * @returns {SphericalCoords} Returns itself.
  72.      */
  73.     limit(phiMin, phiMax, thetaMin, thetaMax) {
  74.         // Limits for orbital controls
  75.         this.components[1] = Math.max(phiMin, Math.min(phiMax, this.components[1]));
  76.         this.components[2] = Math.max(thetaMin, Math.min(thetaMax, this.components[2]));
  77.         
  78.         return this;
  79.     }
  81.     /**
  82.      * Clone this spherical coordinates object.
  83.      * 
  84.      * @returns {SphericalCoords} A clone of the spherical coordinates object.
  85.      */
  86.     clone() {
  87.         return new Lore.SphericalCoords(this.radius, this.phi, this.theta);
  88.     }
  90.     /**
  91.      * Returns a string representation of these spherical coordinates.
  92.      * 
  93.      * @returns {String} A string representing spherical coordinates.
  94.      */
  95.     toString() {
  96.         return '(' + this.components[0] + ', ' +
  97.             this.components[1] + ', ' + this.components[2] + ')';
  98.     }
  99. }