libxrandr XRRGetCrtcInfo() misinterpretation by nouveau or NVIDIA?

Thomas Richter thor at
Fri Jun 19 03:49:51 PDT 2015

Am 19.06.2015 um 12:38 schrieb Chris Wilson:
> Why is it that in the presence of randr1.3 XRRGetCrtcInfo()  returns
> semantically(!) different information
> than XRRGetCrtcInfo() with randr1.2 only? In the former case, it returns
> the entire panning area. In the latter case,
> it returns only the visible monitor size.
> RR1.3 introduced panning. Without panning, the visible area of the CRTC
> is exactly defined by the mode, rotation, transformation and offset.
> Basically nvidia have only implemented half of the extension. They allow
> you to set panning, but don't report it back to the application.
> -Chris
Thank you, now that makes sense! IOW, the panning I have with randr1.2
here on NVIDIA is a proprietary extension
 to randr1.2 that is not officially present and was added "on top"
without implementing the 1.3 interface that actually
communicates panning information.

Ok, so source of the bug identified. NVIDIA. If I only had a chance to
talk to some engineer there and not just the
average "support" people...

Thanks for your patience!


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