Pango Hinting when using freetype backend

[Volker Vogelhuber <v vogelhuber digitalendoscopy de>]

I would have suspected, that using the freetype backend for pango will 
result in the same output rendered to screen as when using the cairo 
backend.
Testing it by calling:
pango-view --backend=cairo --font="DejaVu Sans" test.txt
and
pango-view --backend=ft2 --font="DejaVu Sans" test.txt
showed that this is not the case. When playing with the hinting 
parameter  "--hinting" it seems like the freetype backend completly 
ignores hinting. At least when setting hinting=none the cairo backend 
shows similar results as when using the freetype backend with any 
hinting setting.

I'm asking because I'm currently try to add the pango library (without 
cairo because of the big dependencies added by it) to our own software. 
And the rendering results look a bit blurry.

Calling pango_ft2_font_map_set_resolution and 
pango_ft2_font_map_set_default_substitute with the following substitute 
function:

static void substitute_func (FcPattern *pattern, gpointer   data 
G_GNUC_UNUSED)
{
  if (OPT_HINTING != HINT_DEFAULT)
    {
      FcPatternDel (pattern, FC_HINTING);
      FcPatternAddBool (pattern, FC_HINTING, OPT_HINTING != HINT_NONE);

      FcPatternDel (pattern, FC_AUTOHINT);
      FcPatternAddBool (pattern, FC_AUTOHINT, OPT_HINTING == HINT_AUTO);
    }
}

does not seem to make any difference  regardless of what DPI and 
OPT_HINTING I have defined.
So after testing the freetype backend with the pango-view example under 
Ubuntu 13.10 I'm wondering if hinting is configurable (and usable) at 
all when using the freetype backend.


Any help would be greatly appreciated.

Regards,
    Volker