Re: [gentoo-user] Re: big fonts after Xorg update

[Paul Hartman <paul.hartman+gentoo@gmail.com>]

On Mon, Oct 19, 2009 at 3:18 PM, Thorsten Kampe
<thorsten@thorstenkampe.de> wrote:
> * Nikos Chantziaras (Fri, 16 Oct 2009 02:32:21 +0300)
>>
>> On 10/16/2009 02:22 AM, Thorsten Kampe wrote:
>> >
>> > I just updated from xorg-server 1.3.0.0-r6 to 1.6. After the upgrade I
>> > see a lot of applications have now much bigger fonts then they used to
>> > have (the fonts and font sizes of course are the same - they just appear
>> > bigger). Examples are KDM, Konsole, most KDE apps (GNOME applications
>> > seem not to be affected).
>> >
>> > The increased fonts looks a bit as when I connect via VNC to the diplay
>> > manager session (with the Xorg VNC module). I had the same effect
>> > already when I tried to upgrade to Xorg 1.5 (which was why I had to
>> > revert back to 1.3).
>> >
>> > This is a VMware virtual machine with the VMware tools installed and
>> > running.
>> >
>> > What can I do to avoid the "font increase"?
>>
>> The best thing you can do with VMWare (from my own experiences) is to
>> force 96 DPI in /usr/share/config/kdm/kdmrc.  Find this line:
>>
>>    ServerArgsLocal=-nolisten tcp
>>
>> And add "-dpi 96" to it:
>>
>>    ServerArgsLocal=-nolisten tcp -dpi 96
>
> That was the solution. I checked the resolution before the upgrade with
> "xdpyinfo | grep resolution" (Tip from the German list): 75 dpi.
> Afterwards: 96 dpi. Setting it to 75 solved the issue.
>
> I'd still like to know what exactly changed and if 75 or 96 is the
> "correct" value. Nevertheless, I have Xorg server 1.6 running and it
> looks fine.

Divide your screen resolution (pixels) by its visible area (inches) to
get DPI. For example my monitor screen is 16 inches wide and 12 inches
tall and I use 1600x1200 resolution. That is 100dpi. In my system this
is autodetected when xorg starts (maybe the nvidia drivers do it?).

Theoretically, I think if the DPI is set correctly, a 10 point font
will be the same physical size on any display.

I think most consumer-grade desktop LCD panels are around 75dpi. Some
mobile phones like Nokia N82 have a really high-density screen,
256dpi. So a website or program that measures its fonts or widgets in
fixed pixels rather than relative to the dpi will look dramatically
different in those cases.

Within programs, using KDE4 daily the DPI seems to be respected almost
eveywhere. Sometimes gtk+ apps will have huge fonts for no apparent
(to me) reason but I seem to be free of that problem at the moment.