void cpdf_set_font (int pdf document, string font name, double size, string encoding)
The cpdf_set_font() function sets the the current font face, font size and encoding. Currently only the standard postscript fonts are supported. The last parameter encoding can take the following values: "MacRomanEncoding", "MacExpertEncoding", "WinAnsiEncoding", and "NULL". "NULL" stands for the font's built-in encoding. See the ClibPDF Manual for more information, especially how to support asian fonts.