set position of the window for multiple monitors

apps/openmw/engine.cpp

@@ -369,6 +369,7 @@ void OMW::Engine::prepareEngine (Settings::Manager & settings)
     windowSettings.fullscreen = settings.getBool("fullscreen", "Video");
     windowSettings.window_x = settings.getInt("resolution x", "Video");
     windowSettings.window_y = settings.getInt("resolution y", "Video");
+    windowSettings.screen = settings.getInt("screen", "Video");
     windowSettings.vsync = settings.getBool("vsync", "Video");
     windowSettings.icon = "openmw.png";
     std::string aa = settings.getString("antialiasing", "Video");

libs/openengine/ogre/renderer.cpp

@@ -266,11 +266,15 @@ void OgreRenderer::createWindow(const std::string &title, const WindowSettings&
     params.insert(std::make_pair("FSAA", settings.fsaa));
     params.insert(std::make_pair("vsync", settings.vsync ? "true" : "false"));
 
+    SDL_Rect display_bounds;
+    if(SDL_GetDisplayBounds(settings.screen, &display_bounds) != 0)
+        throw std::runtime_error("Couldn't get display bounds!");
+
     // Create an application window with the following settings:
     mSDLWindow = SDL_CreateWindow(
       "OpenMW",                  //    window title
-      SDL_WINDOWPOS_UNDEFINED,           //    initial x position
-      SDL_WINDOWPOS_UNDEFINED,           //    initial y position
+      display_bounds.x,           //    initial x position
+      display_bounds.y,           //    initial y position
       settings.window_x,                               //    width, in pixels
       settings.window_y,                               //    height, in pixels
       SDL_WINDOW_SHOWN

libs/openengine/ogre/renderer.hpp

@@ -56,6 +56,7 @@ namespace OEngine
             bool vsync;
             bool fullscreen;
             int window_x, window_y;
+            int screen;
             std::string fsaa;
             std::string icon;
         };