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aa506bfe40
1. svn mv OverLua SSATool athenasub avisynth_prs kanamemo \
motiontracker prs traydict unit_test vsfilter devel/
* See r2749 for full description.
Originally committed to SVN as r2755.
62 lines
2.1 KiB
Text
62 lines
2.1 KiB
Text
Documentation for the fonts interface provided in OverLua
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=========================================================
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OverLua provides a simplified interface to create and manage Fontconfig
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in-memory configurations, create FreeType font face objects from those
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and basic manipulation of these font face objects.
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It is possible to create cairo font face objects from the FreeType font
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face objects, so the fonts can be used in cairo rendering. This is the
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preferred way to produce text in OverLua.
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This interface does not provide means to have Fontconfig load and use
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configuration files, neither system-wide, per-user nor private ones.
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The only way to load and use fonts is to explicitly name the font files
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and load these. The purpose of this is to let OverLua scripts produce
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predictable results, as the same font will always be selected regardless
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of the system the script is running on.
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See also:
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Fontconfig documentation: <http://fontconfig.org/fontconfig-devel/>
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FreeType 2 documentation: <http://www.freetype.org/freetype2/docs/reference/ft2-toc.html>
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Font configuration object
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-------------------------
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OverLua keeps one global Fontconfig configuration object, which is
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implicitly used for all operations. It is accessed through the global
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'fonts' object.
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The following operations are supported:
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success = fonts.add_file(filename)
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Attempts to load the specified font file and add all fonts in it to the
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Fontconfig configuration. This uses the FcConfigAppFontAddFile C function
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to perform the work.
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On return, 'success' is a boolean which is 'true' on success and 'false'
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otherwise.
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cairofont = fonts.select(pattern, cairofo)
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Select the font best matching the pattern given, and return an object
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representing that font.
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The pattern is a Lua table of key=value pairs, with the keys being the
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properties Fontconfig understands, and the values the value you want
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for that property.
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'cairofo' is a cairo font options object. This parameter is optional.
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You can see a list of known properties on: <http://fontconfig.org/fontconfig-user.html>
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This function returns a cairo FreeType font object that can be selected
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into a cairo context for rendering with.
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