Saturday, September 20, 2014

Glyph design: the trick to drawing the letter s





The letter ‘s’ is considered one of the hardest letters in the alphabet to design. It is utterly unrelated to any other letter we have designed so far. Most people can’t handwrite this letter and produce a passable print rendition.

If you are learning the latin script and are struggling with handwriting this letter, do not despair—most of us don’t have a firm grasp on its construction either. Most neat writers (mostly teenage girls) handprint the letter something like a number ‘2’ reflected vertically and rounded slightly. Some people overexaggerate the hooks of the ‘s’ to the point where it approaches a figure ‘8’, others render the letter like a mirrored ‘z’.
Some common handwritten forms of the letter ‘s’.
Some common handwritten forms of the letter ‘s’.
 Even worse is when people try and make bubble letter ‘s’s. Except by experienced bubble letterers, one of two results is almost invariably produced.
I won’t dwell on better techniques for bubbling the letter ‘s’. My point is, that most people utterly fail in drawing this letter because they try to freehand it. You can’t blame them—the ‘s’ contains no straight lines and it has no visible geometric basis. But we type designers must be better than that. Here, I’ll show you an easy, relatively painless method for drawing this letter that relies on its hidden geometric structure.

The letter ‘s’ is poorly defined, even by typography standards. Basically the entire body of the letter, for lack of a better term is referred to as its spine; in serif type, the spine is capped off on both ends by a special kind of serif called a beak serif. But a lack of words to describe the letter does not imply a lack of letter structure. In fact, nearly all letter ‘s’s share the same underlying construction—two slightly skewed overlapping circles.
Left to right: Sabon, Minion Pro, Le Monde Journal, and FB Vogue Didot
Left to right: Sabon, Minion Pro, Le Monde Journal, and FB Vogue Didot
This isn’t some coincidence—it’s how the Romans used to do it on their stone monuments. The bottom circle is always slightly larger than the upper circle, and the upper circle is often sheared slightly left of the bottom circle. Two additional circles can be placed inside the two larger circles to trace out the inside of the curve. If you can position your four circles nicely, drawing the spine of the ‘s’ isn’t hard (try to draw a fresh curve though, it’ll look nicer than if you just stitch the two circles together). First trace around the large upper circle and the smaller lower circle, then make the other side by tracing around the small upper circle and the larger lower circle. You can see how this solves our bubble ‘s’ problem. Try to make the thickest part of the spine as thick as the bowl of the ‘o’.
A good blank for the beak serifs can be taken from an ‘i’ turned sideways. This won’t always work, especially for transitional and didone typefaces, but it turned out nicely for old style Floribunda. The hardest part here was blending the serif bracket into the curves of the ‘s’.
Sometimes the letter benefits from some slight angling of the beaks. Getting the color of the letter right can also be a challenge. In this test text, the top and bottom of the ‘s’s look too thin compared to the rest of the text.
This is because most of its weight is found on a diagonal. Like in the ‘k’, the serifs need to be thickened slightly to provide a counterweight to the thick diagonal.
Do note that when you’re vectorizing this letter, it really helps to keep all its curve points as HV extremas. While this isn’t always true for many other letters, it makes the ‘s’ much easier to edit and avoids serious headaches later on.
Floribunda’s ‘s’ in fontforge.
Floribunda’s ‘s’ in fontforge.
 And here is the test text containing the ‘s’, ‘k’, and ‘g’ :