| // Copyright 2008 The Closure Library Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS-IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| /** |
| * @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 = goog.isDef(opt_x) ? opt_x : 0; |
| |
| /** |
| * Y-value |
| * @type {number} |
| */ |
| this.y = goog.isDef(opt_y) ? opt_y : 0; |
| |
| /** |
| * Z-value |
| * @type {number} |
| */ |
| this.z = goog.isDef(opt_z) ? 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 {@code a} and {@code b}. |
| */ |
| goog.math.Coordinate3.distance = function(a, b) { |
| var dx = a.x - b.x; |
| var dy = a.y - b.y; |
| var 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 {@code a} and {@code b}. |
| */ |
| goog.math.Coordinate3.squaredDistance = function(a, b) { |
| var dx = a.x - b.x; |
| var dy = a.y - b.y; |
| var 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 {@code a} and {@code 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 Error('Conversion from an array requires an array of length 3'); |
| }; |