Hands Lab six virtual hands written by Codex (A to F), and six drawn masters posed as puppets (G to L) · click a card to use that design in the Hand Reader on this browser

New comparison: 04 · Live 3D hand and 05 · Rendered whole-hand sprites →

Chord Hand Letters on the keys

This page needs to be served: opened straight from disk the browser blocks the game's modules, so nothing draws. Open app.ultimatepianist.com/hands-lab, or run python3 serve.py in the repo and open localhost:8471/hands-lab.html.

A to F are code: Codex wrote web/js/theory/hand-virtual.js, a stylised representation of a hand drawn from the fingertip positions (a representation, not an actual hand). G to L are hands Codex drew as images, cut into a palm and five fingers and posed on the same skeleton. Every one takes five fingertips placed from the chord's fingering (1-3-5 on a triad, 1-2-3-5 or 1-2-4-5 on a seventh, the left hand mirrored). F · Glass Ghost is the game's default (Lionel's pick, 2026-09-02); a click on another card tries it in the Hand Reader on this browser only (up-hand-style). The record of the round is the Design Gallery, play/chord-shapes · hand-designs-r3.