Comparing Unicode fonts for Vietnamese

Font samples

• Lucida Grande, default Unicode font in Mac OSX. I use it as my default font, because it handles Vietnamese (and many other languages) so well, even though I have many "designed-for-Vietnamese" fonts. You get Lucida Grande with Mac OSX.
• Vu Phu Tho shows you how combined diacritics should be displayed. It's one of a group of beautiful "designed-for-Vietnamese" Unicode fonts which I can't find anymore on vn.net. (Please contact me if you can't find them, and I may be able to send them to you.). vn.net does have these Unicode fonts designed for Vietnamese:
  • Tri-Chlor Set
  • Web fonts
  • Han Nom fonts, for the ancient Chinese-based writing system.
• Verajja, which will soon be included in the free font Dejavu. Dejavu will be packaged with major distributions such as Debian (soon to be released with support for Vietnamese, for the very first time!). Verajja, other fonts supporting Vietnamese (including Gentium Alt) and fonts designed for Indic languages are available freely from here.
• DejaVu itself, version 2.4. newly released. Although it has the same problems with placement and spacing of diacritics as Verajja (unsurprisingly ;) ), it's a very clear font, and its Book variant promises well as a general-purpose Unicode font. DejaVu fonts are freely available from the DejaVu project page. I can't quite work out why this screenshot doesn't show most of the accented characters: I think the user must not have the encoding/locale set correctly. I'll update this page when I find out. :)
• FreeSans, a member of the FreeFont family, this font from the 26/01/06 snapshot. Some of the accents are much less accurate than in the other fonts shown here. The hook accent above the vowel is frankly peculiar in the FreeMono variant. It's not too good here. However, the text is readable in this screenshot, as discussed below.

Displaying Vietnamese

When displaying Vietnamese, clear and distinct display of vowels and diacritics is essential. To this end, an appropriate font for Vietnamese needs to consider the position of diacritics, and how readers will distinguish them from each other, and from the vowels, when reading prose.

Criteria for displaying Vietnamese

• Diacritics must be aligned exactly to the horizontal centre of the vowel, to avoid them pulling the eye too closely back into preceding, or forward into following diacritics.
• Extra space is needed between the diacritic and the vowel, and between combined diacritics, so they may be readily distinguished when reading.
• Diacritics can be distinguished more easily, if they are less leading and more contained. For example, the acute accent is shorter and more solid and triangular, the hook above is more of a spiral with a centred tail, and the hook on the side has a thin stem and rounded, curving-back top. This type of design leads the eye back into the vowel and its diacritics, establishing the distinct identity of the vowel in the reader's mind before the eye moves on to the next character. This is actually contrary to the design of most prose fonts, which lead the eye through the words. People reading Vietnamese become accustomed to identifying each accented vowel separately as we read. Despite our language being written in a basically Roman alphabet, its conceptual base is the same as Chinese, so reading is less a matter of adding words to build an idea, as of identifying parts of an idea and having it blooming suddenly in your mind, like a flower. :)
• Combined diacritics are not just added, but designed to complement each other. For example, a character with combined circumflex and grave shows the grave lying along the right-hand half of the circumflex, and combined diacritics are of equal weight.
• More space is needed between lines. Currently, Freefont is also being tested for release with Debian, and this screenshot of mixed-up text, even at 16pt, also shows the diacritics above the vowel merging into the previous line. The Freefont authors have received detailed feedback on their font, so we can look forward to it displaying Vietnamese much better in the future.

Comparing specific combined diacritics

The two images below compare specific vowels with combined diacritics, in the three fonts, Lucida Grande, Vu Phu Tho and Verajja, described above. This side-by-side comparison at large font-point-size is particularly useful for analyzing the shape and position of diacritics.

Sample prose

The text is displayed by the Pages, the Mac OSX Unicode publishing program.