RE: [ft] Glyph hinting problem with TT hinter

[Sergey Tolstov]

> -----Original Message-----
> From: Rogier van Dalen [mailto:address@hidden 
> Subject: Re: [ft] Glyph hinting problem with TT hinter
> 
> Point 25 is the problematic point. I've calculated it all; 
> Microsoft rounds the x-coordinate 895.455782 up to 896 (14.0) 
> in an interpolate instruction. It is then rounded to half a 
> pixel, to 14.5 according to the MS interpreter, to 13.5 
> according to FreeType's and mine. A delta instruction then 
> moves it left to 13.5 (12.5). To conclude, the MS rasterizer 
> does faulty rounding here, and a delta instruction could have 
> been spared if they had implemented it properly.
> 
> A related point: do you keep some registry of these discrepancies?
> We've seen a couple now. At some point duplicate bug reports 
> will occur. At some point someone might want to adapt the 
> FreeType interpreter to mimic all MS rounding errors.

Adobe Illustrator 10 draws the glyph fine for that size. I suppose they
use their own font engine, don't they?

Thanks,
Sergey