Re: [ft-devel] Two patches for FT

[Werner LEMBERG]

> The FreeType monochrome rasterizer is capable of dealing with this
> because in "high precision mode", which is selected automatically
> for small character pixel sizes, it uses a grid of 1024 units per
> pixel to decompose the splines.

Are you sure that the TT rasterizer for Windows does the same?

> - the Windows engine is less accurate when computing the
>   intersection of bezier curves with scanlines

This is my opinion too.

> - the font was developed on Windows, and the DELTAP offset was found
>   through trial and error on this platform to disable the pixel on
>   it.

Indeed.  The delta is unnecessarily small; they could increase it by
one unit without changing the result, and it would be just fine.

> An easier fix would be to hack the interpreter to 'spot' the DELTAP
> instruction and change its offset dynamically on purpose (as long as
> we're sure we're at the correct size, on the correct font).

Urgh.  Perhaps the `high precision' bit can set and unset for sizes
smaller than 24 ppem too?  Then fontconfig could do something for this
particular font.  (Some time passes.)  I've now manually unset the
FT_OUTLINE_HIGH_PRECISION flag -- it doesn't change the result for
glyph `8' in tahoma (but it does for glyph `6').

BTW, the `l' key in ftview is a dummy and hasn't any function.  Shall
we remove it?


    Werner