Re: Font sizing (was Re: [dia] Windows created diagrams are no longer readable)

[Lars Clausen <lars raeder dk>]

On Tue, 2004-05-25 at 00:05, Hans Breuer wrote:
> At 20:11 17.05.04, Lars Clausen wrote:
> >On Mon, 2004-05-17 at 15:19, Hans Breuer wrote:
> > > At 14:14 14.05.04, Lars Clausen wrote:
> > > >On Thu, 2004-05-13 at 22:15, Federico Maggi wrote:
> > > > >       hi,
> > > > > I am sorry if some similar post already exists.
> > > > >
> > >
> > > There were many posts, but none of them had such a misleading subject 
> > yet ;)
> > > [For me "are no longer readable" sounds like a much more serious problem
> > > than just some size mismatch.]
> >
> >Most of those were the Pango 1.2.4+ problem, where fonts indeed did get
> >unreadable.
> 
> Yeah, but there is also stuff like :
> http://bugzilla.gnome.org/show_bug.cgi?id=59364
> 
> http://bugzilla.gnome.org/show_bug.cgi?id=108293
> 
> In general there were (and always will be) issues with font matching 
> between different backends/formats/engines. Usually not so bad as in the 
> Pango 1.2.4 case - or the current case where some magic scaling 
> approximation is broken again.
> 
> [...]
> 
> > > Loading the file with 0.93(Pango/win32) shows some small deviation, some
> > > few percent as expected. But loading the same file into .93(Pango/FT2)
> > > shows that the boxes - and thus the reported text length - are about 30%
> > > smaller. To me this looks like an unacceptable regression - I simply have
> > > too much diagrams done with 0.90 ...
> >
> >Eeek!  First thing I think about there is the magic 70% size reduction
> >that we introduced with Pango in the first place.  Always hated that
> >thing, 'cause I totally didn't understand it.  Ugh.  Maybe we will have
> >to have a 0.93-1 after all.
> 
> IIRC there was some explanation of it in lib/font.c having to do with 72 
> dpi, 100 pixel huge fonts (Dia's original master font size) and maybe Dia's 
> 20 pixels are a centimeter. OTOH it may have been completely bogus ;-)

Tried playing around with the DPI, got the font size to be just about
right with Dia adjusting for it, at 1280x1024 after measuring the
monitor and putting that in.  But other monitor resolutions mess it up. 
Just removing the 0.7 factor makes the fonts be about 10% too large.

Why does this stuff keep messing up?

-Lars