Re: Compiling the CVS Tree



At 04:57 29.12.02 -0600, Lars Clausen wrote:
On Sat, 28 Dec 2002, Janne Heikkinen wrote:
[...]
Another problem I have with CVS version is that fonts are really huge,
with following change to lib/font.c I get normal sized fonts:

static real global_size_one = 1.0; /* 28.35; */

This value is what converts between centimeters (used internally in Dia)
and points:  72 pt/in / 2.54 cm/in = 28.35 pt/cm.  This might be the same
error that Steffan ran into:  
http://bugzilla.gnome.org/show_bug.cgi?id=99876

Hans also mentioned having to have that as 1.0 or thereabouts.  How very
confusing. 

Nope. The FREETYPE code is using this factor _twice_ which IMO is 
questionable. The one definition as constant like the comment says
is ok, but just using it a second time as in
lib/font.c:dia_font_build_layout 

#ifdef HAVE_FREETYPE
    height *= global_size_one;
#elif defined G_OS_WIN32
    height *= 0.7;
#endif

appears to be wrong. It would be nice to know if changing only
the second appearence to 1.0 would solve the 'huge fonts problem'.

My current - unverfied - interpretation is as follows:
- Pango is expecting its size in points, thus we need to translate
  from Dia's centimeter to point. See comment about global_size_one.
- Pango gives font sizes in pixels (drawn). This size is infuenced by
  the resolution of the monitor (or what X or GDI thinks it is).
  There is some code in pango/pango/pangowin32-fontmap.c which does
  exactly this :

  fontmap->resolution = PANGO_SCALE / GetDeviceCaps (pango_win32_hdc,
LOGPIXELSY) * 72.0;

  It maybe be possible to get on the correct factor with the attached
test program. Or after looking at it's output on my notebook maybe 
not :-(

D:\devel\my-gtk\simples>fontres
Screensize is 800x572 pixels  211x158 mm
Resolution 96x91 dpi
Pixels per cm : 37.9 x 36.2
Dia's magic font factor should be 0.527500(w) or 0.552448(h)

The best working factor for win32 is between 0.7 .. 0.71 which
could be :
        - 72 dpi / 96 dpi
        - 20 / 28.35
        - something completely different

As Lars says: 'How very confusing' :)

Correct fix is probably to edit some X or pango configuration file
but I don't know excatly what file I should edit.

That differs from distribution to distribution.  Can't help you yet.

Another theory where this second factor comes from would be nice ...

        Hans

Attachment: fontres.c
Description: Text document


-------- Hans "at" Breuer "dot" Org -----------
Tell me what you need, and I'll tell you how to 
get along without it.                -- Dilbert


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]