In article <[EMAIL PROTECTED]>, Kezhong Zhou <[EMAIL PROTECTED]> wrote:
> I use FLTK in my program, with a Fl_Menu_Window contains a Fl_Gl_Window. > > Every things goes well untill I extend my desktop to my second monitor. > The action of draw become very slow, I could see the scanline goes up from > the bottom to the top. You didn't mention your operating system, however these kind of performance issues with GL are generally due to driver issues. FLTK does not known if the GL window is being extended to another monitor. > When I use Single Monitor mode, every thing goes well again. The draw > procedure is fast enough to treat my eyes. > > Does anyone know something about this? This is a common GL problem, not related to FLTK. Your card or driver may handle the second monitor in a different way. Ensure that the visual modes for both monitors are the same, otherwise the driver might resort to software-only when dragging a window from one monitor to the other. Your card/driver might also not support context sharing across monitors: if your window spans two monitors there will be a huge performance drop. This is typical with most ATi cards, or with NVidia quadro chips, when using the two distinct video outputs; for example. Please use the "fltk-opengl" mailing list for replies. If you can post some details about your OS/video card maybe someone can help. _______________________________________________ fltk-opengl mailing list [email protected] http://lists.easysw.com/mailman/listinfo/fltk-opengl
