Re: [ft-devel] Autohinter: stem darkening, first rough prototype

[Dave Arnold]

On 8/26/2015 6:02 AM, Alexei Podtelezhnikov wrote:
> On Tue, Aug 25, 2015 at 6:50 PM, Dave Arnold <address@hidden> wrote:
> > It should be monotonic. It should have a minimum of
> > around .4 or .5 pixels. It should go to zero at around 2 pixels.
> darkening = stem < 2 ? 0.5 - stem / 4 : 0;  /* THIS IS IT! */
>
> Why does it have to be more complex than this and be so kinky?
> Perhaps, the piecewise-linear function was fitted specifically for
> light regular and bold, wasn't it? I am just guessing, while wandering
> if we really need it.
> .
Your simplified function may be good enough. We did the testing years ago and 
we looked at a lot of waterfall documents with a lot of fonts! If we tried a 
simplified two-piece function like this, I don't recall the results. Maybe I'm 
just being lazy and not wanting to repeat the testing :-) .

Thanks.
-Dave