[cairo] Font size issue when using pango + cairo

[Behdad Esfahbod]

Peter Clifton wrote:
> On Wed, 2009-01-07 at 03:13 -0500, Behdad Esfahbod wrote:

> Any specific bugs you're thinking of there.. since I'm going to have to
> switch metrics hinting off for gEDA rendering (the scaling issue).
> Unfortunately, the hinting of individual glyphs doesn't always give
> quite as legible a result as our own font rendering with pixel hinting,
> but I'm not sure really what to expect here.

Quite a few:

  http://bugzilla.gnome.org/show_bug.cgi?id=457990
  http://bugzilla.gnome.org/show_bug.cgi?id=341481
  http://bugzilla.gnome.org/show_bug.cgi?id=566488

And some others.

> With metrics hinting off, and glyph hinting still enabled, at some small
> zoom levels, rendering with Helvetica, I end up with some cases where an
> i will touch an adjacent glyph on the RHS, but have 2px space on the
> LHS. (The kerning doesn't look perfect at other zoom levels though - I
> can post some screenshots if that would help).

Those cases can be improved when we extend cairo to export LHS/RHS hinting
deltas...

behdad

> Since it is within the layout being rendered, we could afford (say) a
> single pixel's worth of metric hinting here. Is there any milage in a
> "slight" metric hinting mode?