Font matching flags for SysFont find routine.
Values:
| IG_PDF_SYSFONT_MATCH_NAME_AND_CHARSET | 0x0001 | Match the font name and character set. |
| IG_PDF_SYSFONT_MATCH_FONT_TYPE | 0x0002 | Match the font type. |
| IG_PDF_SYSFONT_MATCH_WRITING_MODE | 0x0004 | Match the writing mode, that is, horizontal or vertical. |