Re: [ft-devel] Playing with FT_CONFIG_OPTION_SUBPIXEL_RENDERING

[Ismail Donmez]

Hi,
27 Eyl 2006 Çar 19:34 tarihinde şunları yazmıştınız:
[...]
> Yes, libXft (and Cairo) should be modified. Here's how the thing is
> supposed to work:
>
> if you don't enable FT_CONFIG_OPTION_SUBPIXEL_RENDERING on your build of
> FreeType, libXft will be forced to display normal "gray" anti-aliased text,
> due to the algorithm it's currently using to filter the colors.
>
> if you enable FT_CONFIG_OPTION_SUBPIXEL_RENDERING on your build of
> FreeType, and only use a vanilla libXft on top of it, you're not going to
> see *any* changes compared to a previous version of the library.
>
> that's because the built-in color filtering must be enabled by calling
> FT_Library_SetLcdFilter( library, FT_LCD_FILTER_DEFAULT ) before loading
> any glyphs.
>
> However, if you do add this to a vanilla libXft right now, you'll get poor
> results as well, because libXft will do its own color filtering on top of
> the one performed by FreeType !
>
> So, I'll try to provide patches soon that essentially modify libXft and
> Cairo to:
>
>   - not perform any color filtering on their own
>   - call FT_Library_SetLcdFilter in the proper places
>
> this should remove any infringing code from these libraries, and provide
> the same "optimized" rendering than the one obtained through my patch, if
> your FreeType build has SUBPIXEL_RENDERING turned on.
>
> Hope this helps,

Sure it does! Thank you David. I think one could fix also poppler to do the 
same so we could get better pdf rendering aka Adobe's CoolType, I will have a 
look at it.

Regards,
ismail

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