Hi! I was presenting two possibilities:
1) If the application needs to use the three displays "as one" - in a real xinerama mode for example, where the user can drag objects from one screen to another, then I think that it will be difficult to coordinate the seperate DFB processes closely enough to get the timings on the graphics just right. And there are many other problems to deal with in this case - each screen would have its own cursor and inputs, how to deal with that, etc... I think this would be really hard. 2) On the other hand, if the application is using the screens independantly, there may not be any need to coordinate DFB at the level of the graphics. For example, consider an Application with one "user input screen" and two large "display terminals". In this case, each DFB process is a seperately running application, doing its own job on its own screen. Whenever the user enters new data on the input screen, the data is stored (filesystem, database), and a message is sent to the other DFB processes. These processes react to the message by loading the data, and displaying it on their screens, something like that. In order to send the message from one process to the others, there are many options: You could develop your own protocol, using a pipe or network socket. You could use an area of shared memory and implement a shared queue. Or you could use higher-level solutions for interprocess communication, like CORBA. The point is that in this example, there is no real need to coordinate DFB at the level of graphics timings, so the problem is really reduced to the normal problem of interprocess communication. Regards, Richard > -----Ursprüngliche Nachricht----- > Von: Pandit Panburana [mailto:[EMAIL PROTECTED] > Gesendet: Donnerstag, 23. November 2006 12:18 > An: Unger Richard; Gerd Alber; [email protected] > Betreff: Re: [directfb-dev] Access more than one FrameBuffer > device in oneprocess > > Hello Richard, > > Could you please elaborate in more how to use shared > memory and pipes etc. to coordinate multiple DFB processes? > > Thank you, > -Pandit > > > ----- Original Message ---- > From: Unger Richard <[EMAIL PROTECTED]> > To: Gerd Alber <[EMAIL PROTECTED]>; [email protected] > Sent: Thursday, November 23, 2006 4:26:53 AM > Subject: Re: [directfb-dev] Access more than one FrameBuffer > device in oneprocess > > > Hi! > > Currently, DFB only handles one Framebuffer device. > > The best way to solve your problem depends a bit on what you > are trying to do. > > If you use the three FrameBuffers largely independantly of > each other, you may be able to use multiple DFB processes, > and coordinate their activities using standard techniques > (shared memory, pipes, etc). > > If the three Framebuffers are to be used in a coordinated > way, I think the problem will be quite difficult. The three > framebuffers will each have their VRAM and timings which > would need to be used in a synchronized way to achieve, for > example, smooth motion from one display to another. :-/ > > Richard Unger > > > > -----Ursprüngliche Nachricht----- > > Von: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] Im Auftrag von Gerd Alber > > Gesendet: Mittwoch, 22. November 2006 19:12 > > An: [email protected] > > Betreff: [directfb-dev] Access more than one FrameBuffer device in > > oneprocess > > > > Hi! > > > > I try to access 3 FrameBuffer in one process (application). > > On my powerpc I have three FrameBuffer devices (dev/fb0 > > dev/fb1 dev/fb2). Over these I can paint on three LCD > displays. Every > > FrameBuffer has on screen and one layer. > > The architecture of DirectFB seems to can handle only with one > > FrameBuffer device per process (only one IDirectFB). > > What is the best way to solve my problem? > > > > - Write a gfxdriver like matrox to access over layers the 3 > > FrameBuffer? > > - Try to manage more than one IDirectFB (when it is possible). > > > > Or exist a tool like Xinemara with can do that? > > > > In my final system, I'll be able to develop application > with wxWidgets > > (www.wxWidgets.og) which can handle more than one screen over the > > dfb-port. > > > > Sorry for my bad English and > > Thanks for your help > > > > Gerd Alber > > > > > > _______________________________________________ > > directfb-dev mailing list > > [email protected] > > http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev > > > > _______________________________________________ > directfb-dev mailing list > [email protected] > http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev > > > > ________________________________ > > Everyone is raving about the all-new Yahoo! Mail beta. > <http://us.rd.yahoo.com/evt=45083/*http://advision.webevents.y > ahoo.com/mailbeta> > _______________________________________________ directfb-dev mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev
