John Documented InitWindowPosition extensions and added some kbd fn info.

[freeglut] / freeglut-1.3 / freeglut_display.c

diff --git a/freeglut-1.3/freeglut_display.c b/freeglut-1.3/freeglut_display.c
index 91f6b6a..7f7e3c1 100644 (file)
--- a/freeglut-1.3/freeglut_display.c
+++ b/freeglut-1.3/freeglut_display.c
@@ -7,10 +7,6 @@
  * Written by Pawel W. Olszta, <olszta@sourceforge.net>
  * Creation date: Fri Dec 3 1999
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
@@ -80,6 +76,11 @@ void FGAPIENTRY glutSwapBuffers( void )
 
 #if TARGET_HOST_UNIX_X11
     /*
+     * If it's single-buffered, we shouldn't be here.
+     */
+    if ( ! fgStructure.Window->Window.DoubleBuffered ) return ;
+
+    /*
      * Issue the glXSwapBuffers call and be done with it
      */
     glXSwapBuffers( fgDisplay.Display, fgStructure.Window->Window.Handle );