Index: supertux/src/gameconfig.hpp
===================================================================
--- supertux/src/gameconfig.hpp	(revision 4539)
+++ supertux/src/gameconfig.hpp	(working copy)
@@ -36,6 +36,8 @@
    */
   int screenwidth;
   int screenheight;
+  int aspectwidth;
+  int aspectheight;
 
   bool use_fullscreen;
   bool show_fps;
Index: supertux/src/main.hpp
===================================================================
--- supertux/src/main.hpp	(revision 4539)
+++ supertux/src/main.hpp	(working copy)
@@ -24,9 +24,9 @@
 void wait_for_event(float min_delay, float max_delay);
 
 /// The width of the display (this is a logical value, not the physical value)
-static const float SCREEN_WIDTH = 800;
+extern int SCREEN_WIDTH;
 /// The height of the display (this is a logical value, not the physical value)
-static const float SCREEN_HEIGHT = 600;
+extern int SCREEN_HEIGHT;
 
 // global variables
 class JoystickKeyboardController;
Index: supertux/src/textscroller.cpp
===================================================================
--- supertux/src/textscroller.cpp	(revision 4539)
+++ supertux/src/textscroller.cpp	(working copy)
@@ -118,7 +118,9 @@
 void
 TextScroller::draw(DrawingContext& context)
 {
-  context.draw_surface(background.get(), Vector(0,0), 0);
+  context.draw_filled_rect(Vector(0, 0), Vector(SCREEN_WIDTH, SCREEN_HEIGHT),
+      Color(0.6f, 0.7f, 0.8f, 0.5f), 0);
+  context.draw_surface(background.get(), Vector(SCREEN_WIDTH/2 - background->get_width()/2 , SCREEN_HEIGHT/2 - background->get_height()/2), 0);
 
   float y = SCREEN_HEIGHT - scroll;
   for(size_t i = 0; i < lines.size(); i++) {
@@ -164,8 +166,8 @@
 void
 InfoBox::draw(DrawingContext& context)
 {
-  float x1 = 200;
-  float y1 = 100;
+  float x1 = SCREEN_WIDTH/2-200;
+  float y1 = SCREEN_HEIGHT/2-200;
   float width = 400;
   float height = 200;
 
Index: supertux/src/gameconfig.cpp
===================================================================
--- supertux/src/gameconfig.cpp	(revision 4539)
+++ supertux/src/gameconfig.cpp	(working copy)
@@ -44,6 +44,8 @@
 
   screenwidth = 800;
   screenheight = 600;
+  aspectwidth = 4;
+  aspectheight = 3;
 
   enable_script_debugger = false;
 }
@@ -70,6 +72,8 @@
     config_video_lisp->get("fullscreen", use_fullscreen);
     config_video_lisp->get("width", screenwidth);
     config_video_lisp->get("height", screenheight);
+    config_video_lisp->get("aspectwidth", aspectwidth);
+    config_video_lisp->get("aspectheight", aspectheight);
   }
 
   const lisp::Lisp* config_audio_lisp = config_lisp->get_lisp("audio");
@@ -98,6 +102,8 @@
   writer.write_bool("fullscreen", use_fullscreen);
   writer.write_int("width", screenwidth);
   writer.write_int("height", screenheight);
+  writer.write_int("aspectwidth", aspectwidth);
+  writer.write_int("aspectheight", aspectheight);
   writer.end_list("video");
 
   writer.start_list("audio");
Index: supertux/src/main.cpp
===================================================================
--- supertux/src/main.cpp	(revision 4539)
+++ supertux/src/main.cpp	(working copy)
@@ -61,6 +61,9 @@
 JoystickKeyboardController* main_controller = 0;
 TinyGetText::DictionaryManager dictionary_manager;
 
+int SCREEN_WIDTH;
+int SCREEN_HEIGHT;
+
 static void init_config()
 {
   config = new Config();
@@ -210,6 +213,7 @@
             "  -f, --fullscreen             Run in fullscreen mode\n"
             "  -w, --window                 Run in window mode\n"
             "  -g, --geometry WIDTHxHEIGHT  Run SuperTux in given resolution\n"
+            "  -a, --aspect WIDTH:HEIGHT    Run SuperTux with given aspect ratio\n"
             "  --disable-sfx                Disable sound effects\n"
             "  --disable-music              Disable music\n"
             "  --help                       Show this help message\n"
@@ -265,6 +269,16 @@
         print_usage(argv[0]);
         throw std::runtime_error("Invalid geometry spec, should be WIDTHxHEIGHT");
       }
+    } else if(arg == "--aspect" || arg == "-a") {
+      if(i+1 >= argc) {
+        print_usage(argv[0]);
+        throw std::runtime_error("Need to specify a parameter for aspect switch");
+      }
+      if(sscanf(argv[++i], "%d:%d", &config->aspectwidth, &config->aspectheight)
+         != 2) {
+        print_usage(argv[0]);
+        throw std::runtime_error("Invalid aspect spec, should be WIDTH:HEIGHT");
+      }
     } else if(arg == "--show-fps") {
       config->show_fps = true;
     } else if(arg == "--no-show-fps") {
@@ -371,6 +385,16 @@
   }
 #endif
 
+  // use aspect ratio to calculate logical resolution
+  if (config->aspectwidth > config->aspectheight) {
+  	SCREEN_HEIGHT=600;
+	SCREEN_WIDTH=600*config->aspectwidth/config->aspectheight;
+  }
+  else {
+  	SCREEN_WIDTH=600;
+	SCREEN_HEIGHT=600*config->aspectheight/config->aspectwidth;
+  }
+
   // setup opengl state and transform
   glDisable(GL_DEPTH_TEST);
   glDisable(GL_CULL_FACE);
@@ -382,7 +406,7 @@
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   // logical resolution here not real monitor resolution
-  glOrtho(0, 800, 600, 0, -1.0, 1.0);
+  glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
   glTranslatef(0, 0, 0);