Re: font renderers in gdk

[Paolo Molaro <lupus lettere unipd it>]

On Tue, Jan 27, 1998 at 03:07:39AM -0800, Christoph Toshok wrote:
> Hey all,
> 
> spurred by raster's comments about FnLib and anti-aliased fonts, I've
> hacked a font renderer abstraction into gdk.

That's fine!
Two comments: some font libs (t1lib for example) requires some
initialization (eg the pathname to a config file).
You want to expose that maybe with a:
+	gint	(*Init)(GdkFontRenderer*, gchar* config_spec);

The other thing we (I?) need is rotation: t1lib can do that
and so freetype, AFAIK.
+   void                (*RenderStringRot)(GdkFontRenderer *, GdkDrawable *,
+                               GdkFont *font,
+                               GdkGC *gc,
+                               const gchar *string,
+                               gint length, gint x, gint y, gfloat angle);

> The function gdk_font_load now checks if the font_name begins with
> "font:" or "fontset:".  If it does, it dispatches through a list of
> registered font renderers until it finds one that actually knows about
> the font.  If it doesn't begin with one of those two strings (such as
> in the case of XLFD's), it uses the default font renderer, which is
> uses XFontStructs/XFontSets.

It can be useful to have a backup scheme: if the fontload routine
doesn't find a font, it should look for the nearest available
(this is hard, I know) and of course it should notify the programmer
as well...

> font:/VeryCoolFont?point-size=24&weight=bold&slant=italic
> 
> Mind you, this format isn't set in stone...  In fact, no code has been

The simpler, the better (this is going to be exposed to the users...).

> The X font renderer is compiled into gdk (but doesn't necessarily have
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is important: the default should be compiled in.

lupus