Re: [ft-devel] GX support now working

[Behdad Esfahbod]

Sascha,

TrueType fonts have a 'non-zero winding' fill rule, whereas Postscript has
'even-odd'.  That's what causes the artifacts.

behdad

On 15-06-03 01:19 PM, Sascha Brawer wrote:
> Hello Werner,
> 
> for testing my 'gvar' handling in fonttools, I've written a little ad-hoc tool
> for MacOS X. It queries the MacOS CoreText library for font outlines at 500pt,
> for various values of width and weight. For the Oslash glyph in Skia 10.0d4e1
> of 2014-08-18 (the version that Apple ships with MacOS 10.10.3), the tool
> emits the attached PostScript file.
> 
> $ git clone https://github.com/brawer/playground
> $ cd playground/fonts/showoutline
> $ make -s && ./showoutline  -font /Library/Fonts/Skia.ttf -glyph Oslash 
> >Oslash.ps
> (Apologies for this code being rather horrible; I only cared about the 
> output).
> 
> Looking at the PostScript output for Oslash, there seem to be plenty of
> artifacts in the glyph. I haven't checked this fully yet, but I wonder if
> those might be caused by bugs in the Skia font? At least, TextEdit on MacOS X
> 10.10.3 shows the very same artifacts; see the attached screenshot.
> 
> Just wondering, what would you think about unit-testing FreeType's 'gvar'
> handling by emitting similar PostScript for some test font? I guess we'd have
> to build some custom font for stress-testing 'gvar', but this shouldn't be so
> hard.
> 
> Best,
> 
> -- Sascha
> 
> 
> On Mon, Jun 1, 2015 at 9:20 AM, Behdad Esfahbod <address@hidden
> <mailto:address@hidden>> wrote:
> 
>     Thanks Werner.  Seems to work fine here!
> 
>     b
> 
>     On 15-05-31 03:38 AM, Werner LEMBERG wrote:
>     >
>     > Folks,
>     >
>     >
>     > GX support should now work in general, please test!  At least with
>     > `Skia.ttf' I no longer see artifacts.
>     >
>     > Adam, I still have problems with two glyphs in `Zycon Regular', namely
>     > the cat and the lizard.  The shapes are heavily distorted if you move
>     > one of the two axes that are active for those glyphs.  As far as I can
>     > see, this is a problem in the font – is it possible that this small
>     > font is a demo only, with those two glyphs intentionally scrambled?
>     > Please compare the results on your old OS X machine for verification.
>     >
>     >
>     >    Werner
>     >
> 
>     --
>     behdad
>     http://behdad.org/
> 
> 

-- 
behdad
http://behdad.org/