Re: bad anti-aliasing; what thinks my CRT is an LCD display

[Florian Kulzer <florian@molphys.leidenuniv.nl>]

On Wed, Jan 03, 2007 at 15:26:35 -0500, Daniel B. wrote:
> Florian Kulzer wrote:
> >On Tue, Jan 02, 2007 at 22:53:17 -0500, Daniel B. wrote:
> >>Where is the configuration or auto-detection of whether a video display
> >>device is a CRT or an LCD?  
> ...
> >>It seems that something thinks my display device is an
> >>LCD panel, when actually it's a CRT.
> >
> >Check the file .fonts.conf in your home directory. This is the stanza
> >to turn off RGB antialiasing:
> >
> > <match target="font" >
> >  <edit mode="assign" name="rgba" >
> >   <const>none</const>
> >  </edit>
> > </match>
> 
> Thanks.  I'll try that.
> 
> Does fontconfig always assume (e.g., upon installation) that it should
> do RGB antialiasing, or does it try to detect what kind of display I
> have (e.g., by asking a lower level, say, the X11 server)?
> 
> Where is the display type supposed to be configured or autodetected?

See comments on fontconfig below.

> >... you can try different options for fontconfig
> >by running (as root)
> >
> >dpkg-reconfigure fontconfig-config
> 
> I had tried that, but it didn't seem to be give my any options related
> to antialiasing or the display type.

It allows you to toggle "subpixel rendering" which, AFAIK, is the same
as (or at least closely related to) RGB antialiasing; sometimes this is
also called "subpixel hinting". I think the default is "Automatic" which
means it is turned on if an LCD screen is detected. You can avoid this
by choosing "Never" if you suspect that there is a problem with the LCD
detection.

Furthermore, the hinting style (native or autohinter) also has a
significant influence on how fonts look on the screen. I would recommend
to try different settings to decide which combination is most pleasing
to your eyes. The whole hinting and antialiasing business is a matter of
personal taste, and the best configuration also depends on which fonts
you use. (Not all fonts include the necessary information to allow for
good native hinting.)

-- 
Regards,
          Florian