KernTrip computes optical spacing and kerning from glyph outlines. No manual pair editing — all values come from the shapes themselves.
Two products, one code base:
- Browser tool: open
index.html, drop a TTF/OTF font. - Glyphs 3 plugin:
glyphs/KernTrip.glyphsPlugin(installed from download); Script menu -> KernTrip.
You may test it live in your Browser now and without any further installations.
https://jrgdrs.github.io/KernTrip/
Download from https://jrgdrs.github.io/KernTrip/KernTrip.zip , unzip and doubleclick onto the Plugin to install it into Glyphs 3 (not version 2 but version 4 preview works also ;-). You find the call KernTrip in the Scrpts menu.
For the recommended workflow and what each parameter does, see the How-To for Glyphs.
If you want to build it by yourself, try
bash make.sh # assembles src/ -> ui.html, index.html, KernTrip.zip,
# and installs the plugin into Glyphs 3- Glyph margins are measured in horizontal zones (plus a 64-row fine profile).
- Every pair is classified by its gap profile: convex pairs are set by their closest point (contact model), open pairs by their mean gap (air model); a blend factor beta mixes the two.
- Stem pairs snap to the cadence grid (rhythm) and get their own stem gap style control.
- A 2D distance field guards against collisions, a bias slider trades legibility against readability, and the Equilibrium tab scores how centered every glyph sits between its neighbors.
- The Setup assistant guides through the five design values on live type samples; the final step computes all corpus pairs.
Development notes for Claude Code live in CLAUDE.md.
This concept builds on my teacher Frank Blokland’s work on patterning in Movable Latin Type, as well as Igino Marini’s presentation on iKern at Atypi. It also draws on Andre Fuchs’s collection of the most common kerning pairs.