[Openicc] XRandR and nv/nvidia was: [Re: [argyllcms] Re: ArgyllCMS Version 1.0.0 released]

[Kai-Uwe Behrmann]

Am 08.07.08, 11:19 -0700 schrieb Hal V. Engel:
> On Tuesday 08 July 2008 10:24:26 am Kai-Uwe Behrmann wrote:
> > Am 08.07.08, 08:26 -0700 schrieb Hal V. Engel:
> > > On Tuesday 08 July 2008 06:00:48 am Graeme Gill wrote:
> > > > Kai-Uwe Behrmann wrote:
> > > > > nv/nvidia drivers dont supports XRandR and especially 1.2.
> > > > > I pinged already Aaron Plattner on the xorg list about nv and
> > > > > elsewhere about the nvidia driver.
> > > >
> > > > Why are they claiming to then ? The Argyll XRandR 1.2 code only gets
> > > > executed when XRRQueryVersion(mydisplay, &majv, &minv) returns 1.2 or
> > > > greater, otherwise it falls back to the Xinerama code. With the patched
> > > > code, setting the ARGYLL_IGNORE_XRANDR1_2 environment variable has 
> the
> > >
> > > same
> > >
> > > > effect as the XRandR extension not being present, or returning a
> > > > version < 1.2.
> > > >
> > > > Graeme Gill.
> > >
> > > According to nvidia the nv driver only has support for randr 1.2 for NV5 
> > > GPUs (8xxx and 9xxx cards).  Kai-Uwe is this the type of hardware you
> > > were using?
> >
> > It's a 6200 here.
> 
> 
> OK then it should not have XRandR 1.2 support so it appears that the driver is 
> incorrently reporting that it does have XRandR 1.2 support when it does not.  
> Clearly a driver bug.
> 
> 
> Currently the only option for nvidia hardware < NV5 for RandR 1.2 support is 
> the Nouveau driver which at this point is at best Alpha level code.  It 
> appears that NV4 GPUs (6xxx and 7xxx cards) have the most mature support.  But 
> until these progress some more it may be problematic to use these drivers.

Perhaps, I can try Nouveau. Thanks for the pointer.
 
> > > I was told over a year ago by Aaron Plattner that they had an open ticket
> > > to add RandR 1.2 support specifcally to address the per monitor LUT issue
> > > and on the nvnews linux forums, the forum that the nvidia linux
> > > developers use to interact with users, users regularly complain about
> > > this issue.   Kai-Uwe have you raised the issue there?
> >
> > We talked on nvidia at freenode IRC.
> 
> 
> And did he have anything useful to say?
 
Aaron P. agreed that a unified API to set output properties is desireable. 
Nethertheless nvidia people seems to have the pov of having already 
covered most ground with their NV-CONTROL/metamode stuff.

Tomas gave the following link about a previous discussion:
http://lists.freedesktop.org/archives/xorg/2006-November/019923.html

So our desire, to have a clear set of API's without to handle driver 
specific protocols, apears as a side place in the discussion. Well I would 
say, with enough people making requests to support actual XRandR-1.2, 
might help in our direction of reducing the set of required API's.

In Oyranos is some code to handle special driver features. I consider this 
since XRandR-1.2 as hacks and dont like to spend any more development time 
in this direction, even with lately some features being lost in Oyranos.

> > > Are the video LUT RandR 1.2 features fully functional on any video driver
> > > at this point?


kind regards
Kai-Uwe Behrmann
-- 
developing for colour management 
www.behrmann.name + www.oyranos.org