We are concentrating on developing games which utilise polished 2d graphics engines, rather than 3d. I know it sounds crazy but its what we want to do...
With most 2d engines the number of pixels drawn is usually kept to a minimum, unless there is a huge amount of overdraw going on, then its nearly always faster to draw direct to the framebuffer. If we do need to scroll the whole screen, then we would try to alter start of viewport address rather than transferring the entire screen. I'm just concerned that the DGA extension will be removed with no adequete replacement. The main issue with DGA seems to be the way it requires root privs and can write to other parts of memory. Can we not have some sort of "/dev/dga" device or is this not the place to ask ;) is this not feasible? James On Sat, 6 Mar 2004 19:02:00 -0800 (PST) Mark Vojkovich <[EMAIL PROTECTED]> wrote: > I expect it will go away eventually. It's still the case for > most access patterns that rendering in system memory and then > copying the result to the framebuffer is faster than CPU rendering > directly to the framebuffer. Only the most simple game engines (write- > only SW scanline renderers) can benefit from direct framebuffer access. > Why aren't you using OpenGL? > > Mark. > > On Sun, 7 Mar 2004, James Wright wrote: > > > Hello, > > > > Apologies if this is the incorrect list to post to but i couldn't decide > > between the general "forum" > > list or this one. My question concerns the DGA extension in XFree86, whether it > > will be removed from > > future versions, and the alternatives. We are currently in the process of > > developing games for the > > Linux OS. We require direct access to the video framebuffer, the ability to change > > resolution, refresh > > rate, indexed palettes, and the ability to alter the start screen position pointer > > (for hardware > > scrolling). At first we wrote our 2D drawing libs to use SVGALib, but after > > numerous problems with memory > > leaks and bad support for many gfx cards we switched to X11->DGAv2. We are > > reasonably happy with DGA as > > it stands, with the only annoyance being that it requires root privs. I have seen > > it mentioned that > > DGA could be removed in future XFree86 releases, is this true? If so, what are the > > alternatives for us > > to use? It is obvious that there are alot of apps out there that really can't > > justify the use of DGA, > > but I feel that this application (games) really can benefit from using it. Any > > extra layers between > > our drawing and the framebuffer is just extra overhead and latency for us... > > > > Any sugestions or comments appreciated... > > > > > > Thanks, > > James > > > > > > > > _______________________________________________ > > Devel mailing list > > [EMAIL PROTECTED] > > http://XFree86.Org/mailman/listinfo/devel > > > > _______________________________________________ > Devel mailing list > [EMAIL PROTECTED] > http://XFree86.Org/mailman/listinfo/devel > _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
