Re: [Devel] severe problems with Legendum.otf

[Rogier van Dalen]

Hi,

> - Does the same "incorrect" behaviour happens with FreeType 1
>  (if not, something fuzzy happened when the code was ported to
>  FT2)
>  
I have no idea and I'm not currently able to test it, either.

> - since you've written your own rasterizer, could you check the
>  differences it has with the FreeType one(s) ? Also, does your
>  code renders the MS Core Fonts perfectly ? (I suppose so, but
>  who knows :-)
>  
No, my code does not render all MS Fonts correctly. I have so far fixed 
one or two "undocumented" things with moving twilight points. However, I 
didn't want to copy the behaviour exactly as in FreeType since there 
might be mistakes in there. And I have not (yet) taken the time to fix 
all the problems.

> By the way, I'd like to point the fact that the monochrome renderer
> ignores the "drop-out" mode set by the glyph program(s) because
> experience has shown that this was the only way to get correct
> rendering of most well-hinted fonts. Again, this assumption may
> be wrong, especially if we remove or change some of the "undocumented"
> sections in the interpreter.
>  
This is not a problem affecting Legendum, since it was made to be 
rendered in AA mode.

Seeing how complex this problem is, I wonder: have you ever produced 
dummy fonts with simple glyph programs to test the behaviour of specific 
instructions in isolation, and compared the output from Windows and 
FreeType? If not, I would volunteer to do this, since this would also 
improve my own rasteriser code if I find something useful. (It'd take a 
few weeks though.)

Regards,

Rogier