On 19 Jul 2004 19:34:19 +0200, Juliusz Chroboczek <jch@...> wrote:
> Dear all,
> Many thanks to all of those involved in getting the DRI working on the
> I just installed yesterday the 20040718 snapshot on a laptop with a
> Twister-K running an up-to-date Debian Testing. The installation went
> without a hitch once I realised there's an automated installation
> script (I'll read the README next time).
> A nice side-effect of the installation is decent XVideo support (the
> stock XFree86 server does nearest-neighbour scaling).
There was a hw vertical interpolated scaling enable bit that the stock
driver forgot to set. I found it when merging S3 and Tim's driver.
The new code also uses the BCI on integrated chips like the twister
for mastered image transfer and colorspace conversion. I also have a
patch for some obsure colorkey bug that was sent to me, but alas, it
has slipped my mind for a while and I haven't had a chance to test and
> There are just two minor issues. I've managed to get it to lockup
> twice (X server frozen with 100% cpu, the system can be rebooted
> remotely), but haven't been able to reproduce the problem since.
> The other issue is more annoying: there is visual noise whenever there
> is significant OpenGL activity in a full-screen window (rendered at
> 640x400, scaled to 1024x768); this happens both with amoeba and
> MPlayer. There is no such problem with 640x400 windows.
hmmm...what exactly does it look like? Felix may know more about that.
> Oh, a few questions if any of you have got time. Without any
> customisation, the server reports that it found an AGP 4x chipset, but
> runs in AGP 1x. Setting the server to AGP 4x in the XF86Config
> appears to work. Could anyone explain what's going on? (Oh, and what
> is it supposed to speed up? Texture upload?)
The server defaults to 1x like (all?) other 3d drivers as some older
chipsets had problems with higher agp speeds. Theoretically it should
speed up AGP transfers (just textures at the moment), but in the real
world rarely seems to affect performance.
> The server complains it cannot open /dev/agp_bios (I'm running devfs),
> but doesn't seem to mind. What's that?
I've never heard of that.
> Finally, does anyone know what scaling algorithm is used by the XVideo
> implementation? It looks like nearest-neighbour when downscaling,
> bilinear when upscaling by a reasonable amount, and linear in the Y
> direction when upscaling a lot.
I don't remember off hand. As I recall it varies somewhat depending
on what factor you are scaling it by. Check the source
> Juliusz Chroboczek
> P.S. I'll try to check the list archives, but please be so kind as to
> CC me with any replies.