[mythtv-users] Aspect ratio wrong

Greg Stark gsstark at mit.edu
Thu Apr 6 03:59:40 UTC 2006

"Michael T. Dean" <mtdean at thirdcontact.com> writes:

> Oops.  Just posted and I had guessed TwinView.  Guess I should have kept 
> it more generic.

Yeah, MergedFB is basically the same thing.

> > I
> >don't know how to query the xinerama info to compare but it appears Mythtv is
> >getting the wrong dimensions below (1920x1200 is the other monitor, not the
> >one it's on). So that's already an error.
> >  
> >
> There was a discussion on the archives (involving Daniel (DTK)) about 
> this issue.  I don't remember the resolution (or if they even came to 
> one), but I think they were talking about a way to specify which monitor 
> in a Xinerama/TwinView to use for getting screen dimensions.

Well it wouldn't really matter for me. Both monitors have basically square
pixels. It's only because of the confusion that things are going wrong. But a
friend pointed me towards "xdpyinfo -ext XINERAMA" which gives shows X is the
source of the erroneous data:

XINERAMA version 1.1 opcode: 128
  head #0: 1920x1200 @ 0,0
  head #1: 1920x1200 @ 1600,0

I think this happened when I added a 1600x1200-1920x1600 metamode (because I
suspected that X was sometimes getting the outputs reversed). That would
explain why it used to work and only started failing recently.

> You've specified a DisplaySize according to Myth's 
> how-to-get-100dpi-for-good-themes-rules (which is probably not 
> appropriate anywhere except a dedicated myth frontend).

I didn't specify anything like this as far as I know. Those dimensions are
pretty close to the actual total dimensions of the two monitors (though the
precise arithmetic the driver is using is a bit of a mystery) and I guess 100
dpi really is the resolution. Happy coincidence.

All I've specified is 800x600 gui size because rendering the gui at 1600x1200
was unusably slow. It also wasn't necessary on a non-dedicated frontend.

> ?  Search the archives for the discussion I mentioned above.  Try 
> xinerama, twinview, aspect ratio, etc.

You've helped a lot already. Thanks.


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