--- Felix Kühling <[EMAIL PROTECTED]> wrote: > On Tue, 23 Mar 2004 08:16:49 -0800 (PST) > Alex Deucher <[EMAIL PROTECTED]> wrote: > > > > > --- Felix K_hling <[EMAIL PROTECTED]> wrote: > [snip] > > > Anyway, the reason is that accelerated 3D rendering only works > with > > > tiled memory but the front buffer is linear. > > > > > > Software fallbacks draw to tiled surfaces, which map linear or > tiled > > > memory. If I understand it correctly it shouldn't make any > difference > > > whether the underlying memory is linear or tiled (as long as the > > > tiled > > > surface registers are setup correctly). > > > > That's my understanding as well, but I could be wrong. Also, > tiling > > the front buffer results in lower performance. I'm not sure why. > It > > might have just been due to the way the code was initially > architected. > > your changes to the 3d driver may have fixed that. > > Don't know which changes that would be. The only thing where the > tiling > of the front buffer would make a difference for normal double > buffered > rendering is on buffer swaps. The swapping didn't change. So possibly > blitting to a linear frame buffer is faster than blitting to a tiled > one. Anyway, from Keith's comments about double-buffered visuals > where > the app switches between rendering to front and back buffer, it > sounds > like we really want to have a tiled front buffer.
I'll try and get tiling working again. > > > > > > > > > It seems that the front buffer surface uses a different line > pitch > > > than > > > the back buffer. I don't know why that is. Alex, can this be > changed > > > easily or would it require big changes in the 2D driver? > > > > The pitch is different because of alignment requirements. I think I > > tried changing the front pitch to match the others and it didn't > seem > > to break anything as I recall, so perhaps we can get away with it. > > If it really needs a different pitch it shouldn't be too hard to > adjust > savagespan.c. it should only have a different pitch if you are using linear vs. tiled for the front buffer. With a tiled front buffer the pitch should be the same. > > > Unfortunately, tiling of the front buffer broke when I ported S3's > > changes to Tim's code. I'm not sure what the problem is as the set > up > > is pretty much identical. I never really dug into it too much > since > > linear seemed to work fine for most things. However, back when we > were > > using S3's driver and tiling worked, drawing to the front buffer > was > > still broken (looked the same whether the front buffer was tiled or > > not). > > > > Alex > > > [snip] __________________________________ Do you Yahoo!? Yahoo! Finance Tax Center - File online. File on time. http://taxes.yahoo.com/filing.html ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click -- _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
