radeon MergedFB and vertical monitor offsets

[Alex Deucher]

On Sat, 27 Nov 2004 21:16:27 -0500, Keith Lea <keith at cs.oswego.edu> wrote:
> 
> 
> > Date: Sat, 27 Nov 2004 15:54:16 -0500
> > From: Alex Deucher <alexdeucher at gmail.com>
> > Subject: Re: radeon MergedFB and vertical monitor offsets
> 
> 
> >
> > On Sat, 27 Nov 2004 13:21:36 -0500, Keith Lea <keith at cs.oswego.edu> wrote:
> >
> >>Hi, I'm using the radeon MergedFB mode to use dual monitors on my IBM
> >>T30 laptop with Radeon 7500 Mobile.
> >>
> >>I have a problem: my external monitor sits about 4 inches above my
> >>laptop LCD screen. So, for example, when I move my mouse to the right,
> >>onto the external monitor screen, the mouse jumps up 4 inches visually.
> >>It's disorienting for me.
> >>
> >>On Windows XP, you can drag around the screens to tell Windows where the
> >>monitors are physically located relative to each other. This makes it so
> >>when I move the mouse over to the second screen, it moves down 300
> >>pixels or so, but visually, it's at the same vertical location.
> >>
> >>I was wondering if there's a way to do this with MergedFB mode.
> >
> > if you are talking about locking the viewports (so the frame doesn't
> > move within the virtual desktop), then, no.  there was a patch posted
> > a while back the locked the crtcs into position, but the mouse and
> > non-xinerama aware windows could still end up in the dead space.  The
> > other option is to run the same resolution on both heads so that the
> > viewport doesn't move.
> >
> > Another option is to use "regular" dualhead + xinerama and then set up
> > the offsets in the serverlayout.
> >
> > Alex
> 
> No, this isn't what I meant, I don't think. I don't know what "locking
> the viewports" or "frame doesn't move within the virtual desktop" mean.
> 
> Maybe this will explain it better: I have an LCD and a monitor. I set
> both to 1024x768. I use MergedFB mode to get one giant desktop which
> spans the two, so my desktop is 2048x768. I want to create a virtual
> desktop which contains 2048*768 pixels, but they are not in a rectangle.
> They are in a shape like this:
> 
>        +-----+
> +-----+     |
> |           |
> |     +-----+
> +-----+
> 
> The lower-left box's pixels would be shown on my laptop LCD screen. The
> upper-right box's pixels would be shown on my external monitor. This
> way, my desktop matches the physical locations of my computer screens,
> and when I move my mouse between the two screens, it stays at the same
> vertical visual position.
> 
> Now, again, my question, is there a way to do this with MergedFB mode of
> radeon driver?

No, there's no way to do that with mergedfb.  You'll have to use
regular multihead + xinerama.

Alex

> 
> Thanks,
> -Keith