iOS/buildlibs/armv7/allegro-4.4.2/addons/allegrogl/src/x.c
/* allegro_gl_x_vsync:
 *  Wait for a vertical retrace. GLX_SGI_video_sync is needed.
 */
Wait for a vertical retrace.
Wait for a vertical retrace .
static void allegro_gl_x_vsync(void)
{
	XLOCK();
	if (allegro_gl_extensions_GLX.SGI_video_sync) {
		unsigned int count;
		glXGetVideoSyncSGI(&count);
		glXWaitVideoSyncSGI(2, (count+1) & 1, &count);
	}
	XUNLOCK();
}
static void allegro_gl_x_vsync ( void ) { XLOCK ( ) ; if ( allegro_gl_extensions_GLX . SGI_video_sync ) { unsigned int count ; glXGetVideoSyncSGI ( & count ) ; glXWaitVideoSyncSGI ( 2 , ( count + 1 ) & 1 , & count ) ; } XUNLOCK ( ) ; }
allegro_gl_x_vsync:
  Wait for a vertical retrace.
allegro_gl_x_vsync : Wait for a vertical retrace .