Re: [ft] Font-Metrics, FreeType and Qt.

[address@hidden]

Dear George:

Thank you for responding.

> On Thu, 2009-07-30 at 14:41, address@hidden wrote:
> > Qt on X11 uses FontConfig and FreeType for text rendering.
> > The general ascent/descent/height metrics for most faces
> > (provided by FreeType) appear overstated to the point where
> > the text looks double spaced. (I am referring to text rendered
> > in list-boxes and pop-up windows etc.)
> Remember most sfnt wrappers

What is an sfnt wrapper.

I see reference to this acronym in many places on
the web, but none of them define it.

> contain at least three different values that
> can be used for vertical line spacing. The three different values have
> slightly different meanings and can lead to wildly different line
> spacings.

Three different values ?

1 - I see the FT_FaceRec has a ascender, descender and height.
    These appear to be unscaled and independent of the current
    active size.

2 - The FT_Size record has ascender, descender and height numbers
    which do appear to be scaled per the current active size.
    These are the numbers which were being used and causing the problem.
    These are the numbers I replaced with my hack.

3 - ???

---------------------------------
http://freetype.sourceforge.net/freetype2/docs/reference/ft2-base_interface.html#FT_Size_Metrics

   ascender     
       The ascender in 26.6 fractional pixels. See FT_FaceRec for the details.
   descender    
       The descender in 26.6 fractional pixels. See FT_FaceRec for the details.
   height       
       The height in 26.6 fractional pixels. See FT_FaceRec for the details.