diff --git a/Engine.cc b/Engine.cc
index 9fb6744..bd9daef 100644
--- a/Engine.cc
+++ b/Engine.cc
@@ -496,6 +496,12 @@ int Engine::renderText(const char * text, int mode, Uint8 r, Uint8 g, Uint8 b,
     return 0;
 }
 
+void Engine::getScreenSize(int * width, int * height)
+{
+    *width = m_video.getWidth();
+    *height = m_video.getHeight();
+}
+
 /* called by SDL when the update timer expires */
 Uint32 Engine::updateCallback(Uint32 interval, void * param)
 {
diff --git a/Engine.h b/Engine.h
index 170db2d..85dfee6 100644
--- a/Engine.h
+++ b/Engine.h
@@ -137,6 +137,7 @@ class Engine
         void debug_hook(lua_Debug * debug);
         int renderText(const char * text, int mode, Uint8 r, Uint8 g, Uint8 b,
                 Uint8 br = 0, Uint8 bg = 0, Uint8 bb = 0);
+        void getScreenSize(int * width, int * height);
 
         /* lua services */
         int setCamera(lua_State * L);
diff --git a/Video.cc b/Video.cc
index 138880d..bd7be07 100644
--- a/Video.cc
+++ b/Video.cc
@@ -29,6 +29,8 @@ Video::Video()
 
     m_surface = NULL;
     m_inputGrabbed = false;
+    m_width = 0;
+    m_height = 0;
 }
 
 void Video::start(int width, int height, bool fullscreen, bool grab_input,
@@ -58,6 +60,8 @@ void Video::start(int width, int height, bool fullscreen, bool grab_input,
         }
         m_inputGrabbed = grab_input;
         m_fullscreen = fullscreen;
+        m_width = width;
+        m_height = height;
 
         glEnable(GL_DEPTH_TEST);
         glEnable(GL_LIGHTING);
diff --git a/Video.h b/Video.h
index db33b07..3ed6b01 100644
--- a/Video.h
+++ b/Video.h
@@ -15,10 +15,14 @@ class Video
         int getDefaultWidth() { return m_defaultWidth; }
         int getDefaultHeight() { return m_defaultHeight; }
         void toggleFullScreen() { SDL_WM_ToggleFullScreen(m_surface); }
+        int getWidth() { return m_width; }
+        int getHeight() { return m_height; }
 
     protected:
         int m_defaultWidth;
         int m_defaultHeight;
+        int m_width;
+        int m_height;
         SDL_Surface * m_surface;
         bool m_fullscreen;
         bool m_inputGrabbed;
diff --git a/ag.cc b/ag.cc
index 92d9a77..3451804 100644
--- a/ag.cc
+++ b/ag.cc
@@ -43,6 +43,7 @@ namespace ag
             { "exit", exit },
             { "import", import },
             { "loadTexture", loadTexture },
+            { "getScreenSize", getScreenSize },
 
             { "createBox", createBox},
             { "createStaticBox", createStaticBox},
@@ -337,6 +338,15 @@ namespace ag
         return 1;
     }
 
+    int getScreenSize(lua_State * L)
+    {
+        int width, height;
+        g_engine->getScreenSize(&width, &height);
+        lua_pushinteger(L, width);
+        lua_pushinteger(L, height);
+        return 2;
+    }
+
     static void addManagedObject(lua_State * L, bool is_static,
             OdeWorld::GeomType geom_type, refptr< vector<float> > args)
     {
diff --git a/ag.h b/ag.h
index debf7ac..0a0a633 100644
--- a/ag.h
+++ b/ag.h
@@ -29,6 +29,7 @@ namespace ag
     int exit(lua_State * L);
     int import(lua_State * L);
     int loadTexture(lua_State * L);
+    int getScreenSize(lua_State * L);
 
     int createBox(lua_State * L);
     int createStaticBox(lua_State * L);