FLTK logo

Synchro to video blank on Windows.

FLTK matrix user chat room
(using Element browser app)   FLTK gitter user chat room   GitHub FLTK Project   FLTK News RSS Feed  
  FLTK Apps      FLTK Library      Forums      Links     Login 
 All Forums  |  Back to fltk.opengl  ]
Previous Message ]New Message | Reply ]Next Message ]

Synchro to video blank on Windows. Richard Lemieux Apr 17, 2013  
Hi everyone,

I am developing an application showing running sonograms on an FLTK panel and I am having a hard time understanding how tho have VBlank synchro work on Windows.  The same app is running without a glitch on Linux.

I have made tests on 1) an ASUS based Intel PC with NVIDIA video running Windows8 and 2) on a TabletPC with Intel video running Windows7.

I am not sure the TabletPC handles VBlank, but my tests show that it behaves differently depending on whether I use,

  wglSwapIntervalEXT1(1) or wglSwapIntervalEXT1(0)

in the OpenGL context of the panel (the ::draw() function).

The NVIDIA based PC definitely supports VBlank but the display still looks choppy in full screen mode although it is not too bad otherwise.

The program is usable but I would much prefer to solve this issue since most users would run the Windows version.

I welcome any clue on how to setup VBlank on a FLTK app on Windows.  Of course I already played with the NVIDIA setting utilities and tried all related settings there.  I have checked the timings and I can check that the painting of the video buffer occurs just before the VBlank is due (if I understand correctly).  The same timing approach works well on Linux.
Direct Link to Message ]
Previous Message ]New Message | Reply ]Next Message ]

Comments are owned by the poster. All other content is copyright 1998-2024 by Bill Spitzak and others. This project is hosted by The FLTK Team. Please report site problems to 'erco@seriss.com'.