Re: Rendering with xft and hinting

[Owen Taylor <otaylor redhat com>]

Soeren Sandmann <sandmann daimi au dk> writes:

> Keith Packard <keithp keithp com> writes:
> 
> > > Can it read that field in TrueType fonts that tells for which sizes
> > > the font is supposed to be rendered antialiased?
> > 
> > I don't know of such a field, what I do know is that some TrueType
> > files provide bitmaps at several sizes. In this case, it's not clear
> > that you wnat to disable anti-aliasing at that size, but FreeType
> > will pick the prerendered bitmaps instead of outlines if you turn
> > anti-aliasing off for those sizes.
> 
> The table I am talking about is the GASP table:
> 
>     http://developer.apple.com/fonts/TTRefMan/RM06/Chap6gasp.html
> 
> The table tells how the font prefers to be rasterized (antialiased
> and/or hinted) at a given size. Presumably, this table will ask for
> the font to be rasterized without antialiasing if the font has a
> bitmap for a certain size.
> 
> > I don't currently expose the list of bitmap sizes for scalable fonts; I 
> > think I could make this work if it would be useful though.
> 
> I don't know how freetype works at all, but if it provides access to
> the GASP table, then I think Xft2 should as well.

There are rumours that use of the GASP table is patented by Microsoft...

Regards,
                                        Owen