Arch Linux

Barghest

Member

From: Hanau/Germany

Registered: 2008-01-03

Posts: 563

Having a bigger resolution than the native one?

Hi,

I own a Samsung NC10 netbook and on a conference a met a guy who own this, too . This poor guy uses Windows on his machine, but I have to admit that he used a feature that I find quite useful: When he connected his netbook to a projector and cloned the output, the resolution of the projector (1024*786 i guess) was higher than the one of the netbook (1024*600). What happened on his windows machine was that he could scroll to the bottom of the screen to see the missing 186 pixels that where shown in the silver screen but cut off on his LVCD.

When I (with Arch) use the NC10 on a projector I can only see the additional 186 pixels on the silver screen and I have no access to the bottom of the LVCD (what can be difficult when the silver screen is behind you ).

So, is it possible, to have this feature in Linux/Arch, too? To use a bigger resolution on the LVCD and "scroll" to the missing parts by moving the mouse to the edges of the screen?

I hope I explained this clearly - otherwise ask for more/other informations

Thanks!

barghest

Veovis Muad'dib

Member

Registered: 2009-06-12

Posts: 43

Re: Having a bigger resolution than the native one?

You explained this quite well, I understood perfectly.  I also would like to know the answer.

Malstrond

Member

From: Germany

Registered: 2009-06-03

Posts: 98

Re: Having a bigger resolution than the native one?

I'm using the xrandr --scale functionality to circumvent this problem on my EEE, although it uses quite a lot of CPU time.
As I'm not using hal, I have my resolutions defined as modelines in xorg.conf, so I calculated one for 1024x768 with gtf, but attempting to use it results in garbled output. I don't think a hardware-side solution is possible.

Barghest

Member

From: Hanau/Germany

Registered: 2008-01-03

Posts: 563

Re: Having a bigger resolution than the native one?

Hey Malstrond,

thanks for the tip. Searching via google for --scale brought me to the function --panning. Its description sounds as if it does what I want.
xrandr --output LVDS --panning 1024x768

For what I've understood, --scale should be possible without xorg.conf:
xrandr --output LVDS --scale 1x1.28

768/600 = 1.28

Nevertheless I'm interested in gtf...may I see the relevant part of your xorg.conf and what you're doing with gtf?

I can't test it at the moment, but I think I'll have the time later/tomorrow.

Malstrond

Member

From: Germany

Registered: 2009-06-03

Posts: 98

Re: Having a bigger resolution than the native one?

Yes ,if you run

xrandr --fb 1024x768 --output LVDS1 --panning 1024x768 --output VGA1 --mode 1024x768 --pos 0x0

(LVDS1=the notebook's screen, VGA1=the beamer) you can scroll the internal panel up and down by moving the cursor to either edge while both outputs use 1024x768 and show the same thing. But this isn't really usable for presentations.

xrandr --output LVDS1 --scale 1x1.28 --output VGA1 --pos 0x0 --mode 1024x768

would stretch LVDS1 vertically to match the beamers resolution. But if you use KMS, --scale is currently broken, it just scales the background, nothing else. Example: Fedora Bug Report, the Arch version has the same problem.

Now, the modeline thingie:
You can calculate one using gtf x y R (x=horizontal width, y=vertical width, R=refresh rate). Running gtf 1024 600 60
results in

  # 1024x600 @ 60.00 Hz (GTF) hsync: 37.32 kHz; pclk: 48.96 MHz
  Modeline "1024x600_60.00"  48.96  1024 1064 1168 1312  600 601 604 622  -HSync +Vsync

The quoted part is just the name to use in xrandr's --mode command, so i removed the _60.00 and included it in the monitor section of my xorg.conf among others (i.e. 640x480 is there so I can run Starcraft in fullscreen ):

Section "Monitor"
   Identifier   "LVDS1"
   VendorName   "ASUS"
   ModelName    "EeePC 1000H"
   Modeline      "1024x600" 48.96  1024 1064 1168 1312 600 601 604 622 -HSync +Vsync
   Modeline      "800x600"   38.22  800 832 912 1024  600 601 604 622  -HSync +Vsync
   Modeline      "640x480"   23.86  640 656 720 800  480 481 484 497  -HSync +Vsync
EndSection

The X server adheres to these settings even if you're using KMS but I don't know if it does if you're using hotplugging because in this case these settings are intended to be generated automatically. I just use them because I don't want to use HAL. But trying to force a resolution bigger than the native one this way doesn't work for me.