Saturday, September 27, 2014

Glyph design: box capital letters ( E L F T )

The box group of capital letters—‘E’, ‘L’, ‘F’, and ‘T’—all have a vertical stem derived from the capital ‘I’ and horizontal arms derived from the ‘Z’. Some—‘E’ and ‘F’—are also divided by a median aligned with the crossbar on the ‘H’. Three of the letters—‘L’, ‘F’, and ‘T’ are degenerate versions of the fourth—the ‘E’. So designing the ‘E’ means we get the other three relatively easily. However ‘E’ is very complex to design, so it helps to draw the ‘L’ first and make the ‘E’ from that.

The ‘L’ takes its stem from the ‘I’, and its arm from the ‘Z’. Experiment with different letter widths to find the best proportions. The joint between the two strokes also benefits from some bracketing on the inside.

The ‘E’ is built by giving another arm and beak serif to an ‘L’. The upper beak serif is always smaller and slightly shorter than the bottom one. It also tends to be less angled. The outer edge of the upper beak should be inside the inner edge of the lower beak serif. The interior corner between the upper arm and the stem exhibits less, if any bracketing than the lower corner.

The ‘E’ also has a median crossbar, like on the ‘H’. It terminates with a double bilateral serif called a tie.
The tie can be made from an ordinary bilateral serif rotated ninety degrees and compressed, thickened, and shortened significantly. The tie terminates well inside of the inner edge of the top beak serif. Note that because ‘E’ contains three horizontal serifs, its serifs are shorter than those of other letters with less stroke density. The stoke density also often means that ‘E’ is mathematically a bit wider than ‘L’ to maintain the same optical width.
The ‘F’ and ‘T’ can be very easily constructed from the ‘E’. The ‘F’ is an ‘E’ missing the lower arm. Because of the reduced stroke density, the letter gets narrower (slightly!), the horizontal serifs get longer, and the median arm migrates downward slightly. Just like in its lowercase version, the right side of the letter’s foot serif is extended to help “balance” the letter.

The ‘T’ is, in turn, an ‘F’ missing the median arm (its upper arm is also reflected on the other side). Since it has an even lower stroke density, its beak serifs are slightly longer than those of both the ‘F’ and the ‘E’. Since the upper arm is reflected, the arms must be compressed significantly to preserve letter width (to some degree). If you are constructing ‘T’ from ‘F’, remember that ‘T’ is symmetrical, an so does not need any “balancing” on its foot serif.

Occasionally the beak serifs on the ‘T’ will overshoot the capital line, much like the one on the lowercase ‘z’. There are, of course, many typefaces (like Floribunda) however that sand off those overshoots to create a flat-topped ‘T’.