Re: [ft-devel] Turning off stem darkening by default until all drivers support it?

[Markus Trippelsdorf]

On 2015.11.10 at 13:06 +0100, Nikolaus Waxweiler wrote:
> Hm, so how about the following:
> * FT_LOAD_TARGET_LIGHT is changed to mean "Use native Y-only-snapping with
> linear advances if driver and font supports it and Y-only autohinter with
> linear advances otherwise". That's broadly comparable to what happens on
> Windows with DirectWrite.
> * FT_LOAD_INTEND_LINEAR_ALPHA_BLENDING_AND_GAMMA_CORRECTION is added so that
> a rendering library or toolkit can express its' intent to do what the flag
> says. This flag would then trigger stem darkening except the library user
> wants color bitmaps out of the font or something. Other caveats? What else
> would need to happen?
> 
> This would
> 1. provide something that works well now (CFF hinter for CFF fonts,
> autohinter for everything else) and can be added to in the future (full
> ClearType with linear advance widths support).
> 2. provide other libraries to make use of stem darkening as soon as they
> enable/implement the feature. No user has to suffer heavy glyphs.  And I
> have more time to work on making stem darkening generic within FreeType.
> 
> Everybody wins?

The big problem is that enabling linear blending is a compile time
option for Qt 5. There is no way to control it at runtime AFAIK. 

And because there is no central authority for the Linux desktop, I'm
afraid that your eagerly anticipated big switch to alpha blended fonts
will not happen anytime soon, if ever.

-- 
Markus