Improve OS detection.

LICENSES.md

@@ -13,15 +13,15 @@ Documentation and video/image assets created for the website should be licensed
 - assets/images/media/
 - assets/images/screenshots/
 
-### GNU LGPL 2.0
+### GNU LGPL 2.1
 - assets/images/home/blue_laser.png
 - assets/images/home/blue_super_bullet.png
 - assets/images/home/guided_missile.png
 - assets/bzflag.svg
 - favicon.ico
 
 ### MIT License
-- assets/js/main.js
+- assets/js/main.js (except for the getOS function)
 - assets/js/screenshots.js
 - _data
 - _datasets
@@ -74,6 +74,7 @@ Documentation and video/image assets created for the website should be licensed
 - Operating system logos are copyright and/or trademark their respective owners.
 - [highlight.js (just the monokai.css file for styling)](https://highlightjs.org/) - BSD 3-Clause "New" or "Revised" License
 	- _sass/vendor/highlightjs/
+- assets/js/main.js - [(the getOS function only)](https://stackoverflow.com/a/38241481) by [Vladyslav Turak](https://stackoverflow.com/users/4815056/vladyslav-turak) - CC BY-SA 3.0 Unported
 
 ---
 

_pages/credits.html.twig

@@ -14,7 +14,7 @@ permalink: /credits/
 
         ## Graphics
 
-        - The BZFlag logo (the red tank icon) and the favicon (the blue tank icon) is copyright Tim Riker and licensed under the GNU LGPL 2.0.
+        - The BZFlag logo, the weapon images, and the favicon (the blue tank icon) are copyright Tim Riker and licensed under the GNU LGPL 2.1.
         - [Megaphone by Creative Stall](https://thenounproject.com/icon/147531/) from the Noun Project - CC-BY 3.0 US License
         - [debug by Lemon Liu](https://thenounproject.com/icon/83827/) from the Noun Project - CC-BY 3.0 US License
         - [Book by Deemak Daksina](https://thenounproject.com/icon/1230262/) from the Noun Project - CC-BY 3.0 US License
@@ -28,6 +28,7 @@ permalink: /credits/
 
         - [PhotoSwipe](http://photoswipe.com/) by Dmitry Semenov - MIT License (with one exception: "Do not create a public WordPress plugin based on it")
         - [Plyr](https://github.com/selz/plyr) - MIT License
+        - [getOS function](https://stackoverflow.com/a/38241481) by [Vladyslav Turak](https://stackoverflow.com/users/4815056/vladyslav-turak) - CC BY-SA 3.0 Unported
 
         ## CSS/SCSS
 

assets/js/main.js

@@ -5,24 +5,29 @@
  *
  * @returns {string}
  */
-function guessOS() {
-    if (navigator.appVersion.indexOf('Win') !== -1) {
-        return 'Windows';
+function getOS() {
+    // Source: https://stackoverflow.com/a/38241481
+    // Author: Vladyslav Turak (https://stackoverflow.com/users/4815056/vladyslav-turak)
+    // License: http://creativecommons.org/licenses/by-sa/3.0/
+    var userAgent = window.navigator.userAgent,
+        platform = window.navigator.platform,
+        macosPlatforms = ['Macintosh', 'MacIntel'],
+        windowsPlatforms = ['Win32', 'Win64', 'Windows'],
+        iosPlatforms = ['iPhone', 'iPad', 'iPod'];
+
+    if (macosPlatforms.indexOf(platform) !== -1) {
+        return 'macos';
+    } else if (iosPlatforms.indexOf(platform) !== -1) {
+        return 'ios';
+    } else if (windowsPlatforms.indexOf(platform) !== -1) {
+        return 'windows';
+    } else if (/Android/.test(userAgent)) {
+        return 'android';
+    } else if (/Linux/.test(platform)) {
+        return 'linux';
     }
 
-    if (navigator.appVersion.indexOf('Mac') !== -1) {
-        return 'macOS';
-    }
-
-    if (navigator.appVersion.indexOf('X11') !== -1) {
-        return 'UNIX';
-    }
-
-    if (navigator.appVersion.indexOf('Linux') !== -1) {
-        return 'Linux';
-    }
-
-    return 'Unknown';
+    return 'unknown';
 }
 
 /**
@@ -40,7 +45,7 @@ function replaceDomClass(find, replace) {
 //   - Detect the OS from CSS
 //   - Detect JS usage from CSS
 
-replaceDomClass('os-unknown', 'os-' + guessOS().toLowerCase());
+replaceDomClass('os-unknown', 'os-' + getOS());
 replaceDomClass('no-js', 'js');
 
 // Mobile menu support