forked from mia/Aegisub
62 lines
2.1 KiB
Text
62 lines
2.1 KiB
Text
Documentation for the fonts interface provided in OverLua
|
|
=========================================================
|
|
|
|
OverLua provides a simplified interface to create and manage Fontconfig
|
|
in-memory configurations, create FreeType font face objects from those
|
|
and basic manipulation of these font face objects.
|
|
|
|
It is possible to create cairo font face objects from the FreeType font
|
|
face objects, so the fonts can be used in cairo rendering. This is the
|
|
preferred way to produce text in OverLua.
|
|
|
|
This interface does not provide means to have Fontconfig load and use
|
|
configuration files, neither system-wide, per-user nor private ones.
|
|
The only way to load and use fonts is to explicitly name the font files
|
|
and load these. The purpose of this is to let OverLua scripts produce
|
|
predictable results, as the same font will always be selected regardless
|
|
of the system the script is running on.
|
|
|
|
|
|
See also:
|
|
|
|
Fontconfig documentation: <http://fontconfig.org/fontconfig-devel/>
|
|
|
|
FreeType 2 documentation: <http://www.freetype.org/freetype2/docs/reference/ft2-toc.html>
|
|
|
|
|
|
Font configuration object
|
|
-------------------------
|
|
|
|
OverLua keeps one global Fontconfig configuration object, which is
|
|
implicitly used for all operations. It is accessed through the global
|
|
'fonts' object.
|
|
|
|
The following operations are supported:
|
|
|
|
|
|
success = fonts.add_file(filename)
|
|
|
|
Attempts to load the specified font file and add all fonts in it to the
|
|
Fontconfig configuration. This uses the FcConfigAppFontAddFile C function
|
|
to perform the work.
|
|
|
|
On return, 'success' is a boolean which is 'true' on success and 'false'
|
|
otherwise.
|
|
|
|
|
|
cairofont = fonts.select(pattern, cairofo)
|
|
|
|
Select the font best matching the pattern given, and return an object
|
|
representing that font.
|
|
|
|
The pattern is a Lua table of key=value pairs, with the keys being the
|
|
properties Fontconfig understands, and the values the value you want
|
|
for that property.
|
|
|
|
'cairofo' is a cairo font options object. This parameter is optional.
|
|
|
|
You can see a list of known properties on: <http://fontconfig.org/fontconfig-user.html>
|
|
|
|
This function returns a cairo FreeType font object that can be selected
|
|
into a cairo context for rendering with.
|
|
|