Re: x11: slow drawing after set xtics font

[Ethan M. <merritt@u.washington.edu>]

On Friday 19 June 2009, Allin Cottrell wrote:
> On Fri, 19 Jun 2009, Ben Abbott wrote:
> 
> >
> > On Friday, June 19, 2009, at 12:47PM, "Ethan Merritt" <merritt@u.washington.edu> wrote:
> > >
> > >> > Cannot it get the list via xlsfont, GDFONTPATH, etc. and then use
> > >> > arial/verdana/helvetica/ (i.e. the usual ttf and postscript fonts)?
> > >> >
> > >>
> > >> I like that idea (provided xlsfonts always accompanies x11).
> > >
> > >It does not.  In particular it does seem to be provided by default in xorg
> > >distributions.
> > >
> > >> If we wanted to match a scalable font whose metrics are as close to
> > >> Helvetica as possible, how would that be done with xlsfonts?
> > >
> > >I think you are attacking this from the wrong end.
> > >If Octave wants to use a "standard" font but are worried that the user's font
> > >server may not provide it, you should include a FAQ or trouble-shooting guide
> > >explaining how to add that font to the font server.
> > >
> > >    Ethan
> >
> > That is a reasonable thing to include in the manual, but we'd
> > also like to ensure that the graphics work with the user tries
> > his/her first plot command.
> 
> As author of another program that calls gnuplot to generate
> graphics, I see your point and agree.
> 
> The approach taken by gretl ( http://gretl.sourceforge.net ) is to
> include in the package, as a failsafe, a "known good" free font
> (e.g. FreeSans.ttf) and to make this the default for gnuplot
> rendition. This may require some manipulation of environment
> variables.

Yeah, that's fine for gd/png/pdf but it won't work for x11.  
In order to use an x11 font you have to teach the font server where to find it,
or what it can substitute, which is exactly what I was suggesting as the right 
approach.  X11 programs request fonts by passing a name template in a 
request to the font server.  Knowing a filename doesn't actually help much,
because the lookup process is not based on files or file names.