--- ../original/openttd-1.2.3/src/video/cocoa/fullscreen.mm	2012-10-31 19:38:49.000000000 -0200
+++ src/video/cocoa/fullscreen.mm	2012-11-11 14:26:09.000000000 -0200
@@ -153,7 +153,7 @@
 	CFDictionaryRef    cur_mode;           ///< current mode of the display
 	CFDictionaryRef    save_mode;          ///< original mode of the display
 	CGDirectPaletteRef palette;            ///< palette of an 8-bit display
-
+	NSOpenGLContext	  *context;            ///< OpenGL context
 
 	/* Gamma functions to try to hide the flash from a res switch
 	 * Fade the display from normal to black
@@ -249,6 +249,27 @@
 		CSleep((uint32)(adjustment * 1000));
 	}
 
+	NSOpenGLContext* CreateGLContext(int w, int h, int bpp) {
+		NSOpenGLPixelFormatAttribute attrs[] = {
+			NSOpenGLPFAFullScreen,
+			NSOpenGLPFADoubleBuffer,
+			NSOpenGLPFADepthSize, bpp,
+			0
+		};
+		NSOpenGLContext* myContext = nil;
+		NSOpenGLPixelFormat* pixFmt = [ [ NSOpenGLPixelFormat alloc ] initWithAttributes:attrs ];
+		if (pixFmt != nil) {
+			myContext = [ [ NSOpenGLContext alloc ] initWithFormat:pixFmt
+				shareContext:NO];
+		}
+		[ pixFmt release ];
+		return myContext;
+	}
+
+	void DestroyGLContext() {
+		free(this->context);
+		this->context = NULL;
+	}
 
 	bool SetVideoMode(int w, int h, int bpp)
 	{
@@ -314,6 +335,9 @@
 		if (MacOSVersionIsAtLeast(10, 7, 0)) {
 			this->window_buffer = NULL;
 			this->window_pitch  = NULL;
+			this->context = CreateGLContext(w, h, bpp);
+			[ this->context setFullScreen ];
+			[ this->context makeCurrentContext ];
 		} else {
 #if (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7)
 			this->window_buffer = CGDisplayBaseAddress(this->display_id);
@@ -416,6 +440,8 @@
 
 		this->device_width  = CGDisplayPixelsWide(this->display_id);
 		this->device_height = CGDisplayPixelsHigh(this->display_id);
+
+		DestroyGLContext();
 	}
 
 public: