Tinkering · experiment 006

Six tones, one letter

Sáu thanh, một chữ. Vietnamese writes with the Latin alphabet and then asks it to do something Latin was never designed for: stack two marks on one vowel, and let the top one carry the meaning of the word. Build a letter and watch the stack assemble.

One letter, six words

Every word below is the same three strokes — m, a — plus one mark. The mark is not an accent in the French sense, decorating a vowel you'd still recognise without it. It is the word. Drop it and you have said something else.

• maaangangghost
• màaahuyềnbut, yet
• máaasắcmother
• mảaahỏia grave
• mãaangãhorse
• mạaanặngrice seedling

Build a syllable

A Vietnamese vowel is assembled from up to three parts, and this page colours them apart: the base letter you'd find in any Latin font, thequality mark that turns it into a different vowel (ă, â, ê, ô, ơ, ư — these are separate letters of the alphabet, not variants), and on top of that the tone mark that picks one of six pitches.

The two marks are drawn by different people for different reasons and they land in the same place. That collision is the entire craft problem.

All seventy-two

Twelve vowels, six tones. This is the whole vowel inventory of written Vietnamese — the complete set a font has to draw before it can claim support. Read down a column and you watch one tone mark ride over every possible thing underneath it. Read across a row and you watch one vowel take all six. Click any cell.

Where the mark goes

Marks want the same airspace. The circumflex of ê sits directly over the letter; so does the hook of ả. Put them together and one has to move — the tone climbs, or shifts off-centre, or the whole stack gets shallower. Watch the blue mark in the specimen above as you change the tone: in a well-cut face it holds still and the green mark finds room around it. In a careless one, it flinches.

Below the baseline there is only ever one tenant: nặng, the heavy tone, is the sole mark Vietnamese puts under a vowel. It never collides with another mark — it collides with the line of text beneath it, and with every underline a designer has ever drawn.

hòa, or hoà?

When a syllable has two vowels, which one carries the tone? Vietnamese has never fully settled this. The older convention puts the mark near the middle of the word, which looks balanced. The newer one puts it on the vowel that actually carries the sound, which is linguistically tidier. Both are in print today; publishers pick a house style and defend it.

watch the green mark jump

This is not only an aesthetic quarrel. The two spellings are different sequences of codepoints, so a search box that doesn't normalise both will fail to find half the documents it was asked for.

What a careless font does

Here is the phrase Tiếng Việt — the name of the language — set in three faces. Two of them were drawn with Vietnamese in mind. The third isCinzel, a beautiful inscriptional Roman face used all over the web, including elsewhere on this site.

Cinzel gets partway. It has ă and đ. It does not have ơ, it does not have ư, and of the ninety codepoints in U+1EA0–1EF9 — the block where almost every tonedVietnamese vowel lives — it contains two: Ỳ andỳ, which are only there because Welsh needs them. Its Vietnamese coverage is an accident.

So the moment a tone lands on a marked vowel, the glyph isn't there, and the browser quietly reaches for another font mid-word. Nothing errors. No console warning. The word just stops being set in the typeface you chose, and only a reader of Vietnamese will notice.

coverage measured live in your browser — a face is marked broken when the glyph it draws for ế is identical to the one your fallback font draws

And what a careless setting does

Even a font with every glyph can be ruined by the leading. A tone stacked on a quality mark reaches far higher than any ascender an English typesetter budgets for, andnặng hangs below. Squeeze the lines and Vietnamese is the first script to break.

The count

An English font is done at fifty-two letterforms. A font that can set Vietnamese is not done until it has drawn — and, harder, correctly positioned — a hundred and seventy-eight.

They are not a hundred and seventy-eight original drawings — the marks repeat, the bases repeat. That is exactly what makes the work invisible, and exactly why it gets skipped. The labour is not in drawing the hook; it is in deciding, one hundred and forty-four times, how high the hook sits and how far left it leans when there is already a circumflex under it.

Every Vietnamese person can see, instantly, whether a typeface was finished or merely shipped. We have been reading badly-set diacritics our whole lives. The tell is never the letter — it's the space above it.