The library "libotf" provides the following facilites.
o Read Open Type Layout Tables from OTF file. Currently these
tables are supported; head, name, cmap, GDEF, GSUB, and GPOS.
o Convert a Unicode character sequence to a glyph code sequence by
using the above tables.
The combination of libotf and the FreeType library (Ver.2) realizes
CTL (complex text layout) by OpenType fonts.