[ltp] Dual-head non-scrolling viewport

John Locke linux-thinkpad@linux-thinkpad.org
Thu, 17 Feb 2005 17:34:17 -0800


Alex Deucher wrote:

>>1. The external LCD has a couple of slightly fuzzy bands. I've seen this
>>before when I've set the monitor on another computer to Mandrake's
>>settings for a generic monitor, and they went away when I selected a
>>generic flat panel monitor. It's a Samsung 15" Syncmaster 570S. I have
>>no idea what the difference is between the "Generic" monitor and "Flat
>>Panel"--is this a different Modeline added to the file? Mandrake's
>>wizards don't help configure a second monitor...    
>>
>
>Try changing the hsync and vrefresh (crt2hync and crt2vrefresh if
>using mergedfb) settings for your external monitor.  Many LCDs support
>70Hz refresh rates, but look MUCH better at 60Hz.
>
>  
>
Wow. That did it. I set these two lines:
   Option "CRT2HSync" "48.61"
    Option "CRT2VRefresh" "60"

... and it looks SO much better. Got the Hsync line from this script, 
after giving it the resolution and refresh rate:

http://xtiming.sourceforge.net/cgi-bin/xtiming.pl

Although now my 1400x1050 mode doesn't show up in krandr as an 
option--before, it would give me that resolution on the laptop screen 
and blank the external monitor.

Now I don't see a way of disabling the external monitor without stopping 
X. Is there something I can add to do that?

>>2. KDE loads the task bar on the external monitor, not the laptop
>>screen. Is there a way I can force the task bar to the laptop instead?
>>    
>>
>
>try:
>Option "MergedXineramaCRT2IsScreen0" "true"
>see the radeon man page for more.  However, you may be able to switch
>it within KDE (in GNOME, you can just drag it to whichever head you
>want).
>
>  
>
Huh. Whaddya know? I didn't think of dragging it, but it worked! Very 
cool. And it came back where I left it, when I logged back in!

>  
>
>>3. Here's the tricky one. I'm finding it extremely annoying to have the
>>viewport on the external monitor scroll. I've found I can use the krandr
>>applet to change both screens to have the same height, at 1024x768. Is
>>it possible to set up my system so that I can have two screens at
>>different resolutions, without one of them scrolling? I'm thinking this
>>isn't possible with MergedFB--can I do it with two separate screens,
>>using Xinerama? If I don't use Xinerama, can I set it up so that I can
>>still move the mouse between screens and get the keyboard to work on
>>both screens? If somebody could point me to a good how-to on how to set
>>this up, that would be great!
>>    
>>
>
>It's not really possible with mergedfb.  There are some patch floating
>around that lock the viewport at a particular offset, however, hte
>mouse and potentially windows can still end up in the offscreen areas.
> What you want to do is definitely possible with regular dualhead and
>xinerama.
>  
>
Okay. That's what I thought about MergedFB. I guess I'll do some 
experimenting with multiple screens then--have not yet tried that route, 
I'm still an X newbie...

So somebody mentioned the possibility of choosing a different conf file 
at startup. How do you do this? Does this only work if you use startx, 
instead of having a display manager that starts X automatically at startup?

Thanks for all your help!

Cheers,
--
John Locke
"Open Source Solutions for Small Business Problems"
published by Charles River Media, June 2004
http://www.freelock.com