[cairo] [PATCH] Apply GASP parmeters to TrueType fonts

[Nicholas Miell]

On 01/23/2012 01:06 PM, Andrea Canciani wrote:
> On Mon, Jan 23, 2012 at 8:40 PM, Nicholas Miell <nmiell at gmail.com> wrote:
> 
> The FT_Get_Gasp() function is only available since FreeType 2.3.0, so
> to use it you should bump the version requirement in configure.ac (or
> call it conditionally depending on its availability).

I updated the version requirement to 2.3.0. Five years seems long enough
for everyone to have updated.

> Would it be possible to create a small test that checks if GASP values
> are respected?

If you can find a freely redistributable font that is subject to this
problem, yes. I don't know of any. My test case was the 'N' and 'W'
glyphs in Verdana Bold. (I had hoped that this would also fix the 'fi'
glyph in Calibri, but that seems to be another issue entirely. I suspect
FreeType just doesn't render ClearType fonts the same way as Microsoft's
rasterizer.)

> How do these flags interact with FontConfig and with the user
> hinting/antialiasing settings?
> I hope somebody more knowledgeable about fonts than me will comment.
> In any case, I think we should add a comment explaining the issue.

These flags override FontConfig and the Cairo API settings entirely in
order to always render fonts correctly. I've added a comment to that effect.