Re: [fltk.general] FL_COURIER has invisible underscore with new version

[Michael Bäuerle]

Ian MacArthur wrote:
>
> This does sound a lot like #3321.
>
> Note that the suspicion is that the problem lies not so much with
> the versions of freetype and fontconfig, but with the way the WM is
> interpreting the hinting information about the font.
>
> It may be possible (as Michael B. posted in the thread
> RE: [fltk.general] Overlapping lines [General Use]) to bodge the way
> the WM handles the hinting to make everything work out better.

The interesting thing is that GTK+ uses Xft/fontconfig/freetype too,
but only FLTK seem to have problems with some hinting styles.

[Michael Bäuerle]

MacArthur, Ian wrote:
> Michael Bäuerle wrote:
> >
> > [...]

> > The interesting thing is that GTK+ uses Xft/fontconfig/freetype
> > too, but only FLTK seem to have problems with some hinting styles.
>

> I don't have any feel for what GTK+ does internally, so it may be
> making some "serious effort" to measure how tall the face actually
> is when rendered.
>
> Fltk, I think, tends to assume the face is the height we expect it
> to be, so if the face (when rendered) is actually taller than
> expected, I imagine that would cause the observed effect on the
> display.
>
> I'm not clear whether changing the hinting level would change what
> height is reported for a face at runtime, but I suspect that it
> might, so... Don't know though...

Maybe it is possible to force a working hinting style only for FLTK
applications (directly from the library) as workaround.

No question that a real fix would be better, but this would at least
"just work" without user intervention on systems that use GNOME
components for the GUI (looks like using GDM is sufficient to trigger
the problem even for Xfce).

I use startx on my machines, therefore I never saw this problem on
one of them.

[Martin McDonough]

That's kind of strange, I use startx (using fluxbox as my WM, no dedicated DE) and that's where I've been seeing this issue.

[Ian MacArthur]

On Tue Aug 23 2016 20:18:53, Martin McDonough wrote:
> That's kind of strange, I use startx (using fluxbox as my WM, no dedicated DE) and that's where I've been seeing this issue.

Though I suspect it may be very sensitive to the actual set of fonts that are in play, and how they are hinted.

It may even be sensitive to how the fonts are actually rendered (e.g. the dpi of the display may come into play, even where two systems have the same fonts installed...) though I hope not!