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

[Kai-Uwe Behrmann]

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.
 
> Nvidia's support of the video card LUTs has not been good for a long time.  
> WIth the nvidia driver you can not access the gamma tables for the individual 
> monitors if you are using "TwinView" to handle multi monitor setups.  But you 
> can if you are using Xinerama.  But you can not use any of the composing 
> setups if you are using Xinerama.  So you can have either composting or 
> correctly setup LUTs but not both.  

The compiz project targets at resetting the card LUT to linear and 
integrate a vcgt tag into the CLUT. Still, it should be fixed for people 
who want this feature.

> 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.
 
> 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