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

[Alexei Podtelezhnikov]

On Thu, Aug 27, 2015 at 10:46 AM, Nikolaus Waxweiler <address@hidden> wrote:
>> The look of the function is documented and it blows my mind. I want to
>> know what they smoked. You simply cannot find such beasts in nature
>> short of quantum mechanics. I simply cannot trust that it was
>> optimized rationally by looking at the rendering results, because
>> optimizing in 8-dimensional space is not for humans and their eyes. My
>> head explodes when I look at this function and I have this feeling in
>> my mouth. I am scared and I cannot dare to touch it. God bless those
>> who want to tune it.
>
>
> Could you implement your curve in the context of
> af_loader_compute_darkening() and send it to me? Because my brain currently
> doesn't grok the math behind character and device-pixel space conversion ;D
> Then we can compare and see what's better :)
>

The simplest is to check if you see any difference with this set of parameters:

#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X1   0
#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y1   500

#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X2  2000
#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y2   0

#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X3  2000
#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y3   0

#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X4  2000
#define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y4     0