Platform: ability to pass command-line args to Emscripten browser apps.

doc/changelog.dox

@@ -260,6 +260,9 @@ namespace Magnum {
 -   Added @ref Platform::Sdl2Application::KeyEvent::keyName() "Platform::*Application::KeyEvent::keyName()"
 -   It's now possible to iterate main loop manually using
     @ref Platform::Sdl2Application::mainLoopIteration()
+-   Ability to pass command-line arguments to Emscripten browser apps, see
+    @ref Platform::Sdl2Application and @ref Platform::WindowlessEglApplication
+    for more information
 
 ### Primitives library
 

src/Magnum/Platform/EmscriptenApplication.js

@@ -2,6 +2,8 @@ var Module = {
     preRun: [],
     postRun: [],
 
+    arguments: [],
+
     printErr: function(message) {
         console.error(Array.prototype.slice.call(arguments).join(' '));
     },
@@ -37,6 +39,20 @@ var Module = {
     }
 };
 
+/* Parse arguments, e.g. /app/?foo=bar&fizz&buzz=3 goes to the app as
+   ['--foo', 'bar', '--fizz', '--buzz', '3'] */
+var args = decodeURIComponent(window.location.search.substr(1)).trim().split('&');
+for(var i = 0; i != args.length; ++i) {
+    var j = args[i].indexOf('=');
+    /* Key + value */
+    if(j != -1) {
+        Module.arguments.push('--' + args[i].substring(0, j));
+        Module.arguments.push(args[i].substring(j + 1));
+
+    /* Just key */
+    } else Module.arguments.push('--' + args[i]);
+}
+
 Module.setStatus('Downloading...');
 
 Module.canvas.addEventListener('contextmenu', function(event) {

src/Magnum/Platform/Sdl2Application.h

@@ -229,7 +229,9 @@ The CSS file contains rudimentary style to avoid eye bleeding.
 
 The application redirects all output (thus also @ref Corrade::Utility::Debug "Debug",
 @ref Corrade::Utility::Warning "Warning" and @ref Corrade::Utility::Error "Error")
-to JavaScript console.
+to JavaScript console. It's possible to pass command-line arguments to `main()`
+using GET URL parameters. For example, `/app/?foo=bar&fizz&buzz=3` will go to
+the app as `['--foo', 'bar', '--fizz', '--buzz', '3']`.
 
 ## Usage with iOS
 

src/Magnum/Platform/WindowlessEglApplication.h

@@ -298,7 +298,9 @@ The CSS file contains rudimentary style to avoid eye bleeding.
 
 The application prints all output (thus also @ref Corrade::Utility::Debug "Debug",
 @ref Corrade::Utility::Warning "Warning" and @ref Corrade::Utility::Error "Error")
-to the `<pre>` on the page.
+to the `<pre>` on the page. It's possible to pass command-line arguments
+to `main()` using GET URL parameters. For example, `/app/?foo=bar&fizz&buzz=3`
+will go to the app as `['--foo', 'bar', '--fizz', '--buzz', '3']`.
 */
 class WindowlessEglApplication {
     public:

src/Magnum/Platform/WindowlessEmscriptenApplication.js

@@ -2,6 +2,8 @@ var Module = {
     preRun: [],
     postRun: [],
 
+    arguments: [],
+
     printErr: function(message) {
         var log = document.getElementById('log');
         log.innerHTML += Array.prototype.slice.call(arguments).join(' ') + '\n';
@@ -39,6 +41,20 @@ var Module = {
     }
 };
 
+/* Parse arguments, e.g. /app/?foo=bar&fizz&buzz=3 goes to the app as
+   ['--foo', 'bar', '--fizz', '--buzz', '3'] */
+var args = decodeURIComponent(window.location.search.substr(1)).trim().split('&');
+for(var i = 0; i != args.length; ++i) {
+    var j = args[i].indexOf('=');
+    /* Key + value */
+    if(j != -1) {
+        Module.arguments.push('--' + args[i].substring(0, j));
+        Module.arguments.push(args[i].substring(j + 1));
+
+    /* Just key */
+    } else Module.arguments.push('--' + args[i]);
+}
+
 Module.setStatus('Downloading...');
 
 Module.canvas.addEventListener('contextmenu', function(event) {