game-of-life-text

Type a word, and it gets built out of colliding gliders in Conway's Game of Life. Two gliders per pixel, aimed and delayed so nothing interferes, and the whole thing settles into still-life blocks that spell what you typed.

Runs as a PySide6 desktop app, or in the browser at conway.martinsundal.no.

Desktop app

Needs Python 3.14 (pinned in .python-version) and uv.

uv sync
uv run gol-gui

Type text, hit Generate, then run the board until the settle bar fills. The Text and Board toggles switch between the finished text and the glider seed; Randomize and Blank give you a sandbox to draw in instead.

Browser app

The canvas and the simulation loop are TypeScript. The planner is the same Python package, running in a Pyodide worker — the first visit downloads the WebAssembly runtime and NumPy, then caches them. The first word then builds itself and stops on the generation it settles.

mise run web    # builds dist/ and serves it on :8000

Keyboard: space run/pause, s step, r reset, t target/board, d draw, g ghost, f fit, +/- zoom. Drag pans, the wheel zooms. export .rle writes the pattern in RLE, so it opens in Golly or LifeViewer.

The page follows the system light or dark setting; the switch in the header overrides it and is remembered. Both palettes live in web/styles.css, which is also where the canvas reads its colours from.

How it works

The renderer turns glyph pixels into 2x2 blocks. The planner walks those blocks outward from the center, and for each one picks a two-glider synthesis whose launch direction and delay keep its gliders clear of every block already placed and of the blocks still to come. Constructions are verified by simulation before anything is shown.

Layout

Path	What it is
src/game_of_life_text	Simulator, font, planner, GUI, browser bridge
web/	Browser app: TypeScript, HTML, stylesheet, webfont
scripts/build_web.py	Stages dist/; tsc compiles into it
tests/	pytest for Python, vitest under tests/web

Development

mise run check      # everything below, in one go
mise run test       # pytest
mise run test:web   # vitest
mise run lint       # ruff check + ruff format --check
mise run lint:web   # eslint + prettier + markdownlint
mise run typecheck  # ty
mise run build      # dist/

Without mise: uv run pytest, uv run ruff check, uv run ty check, npm test, npm run typecheck, npm run lint, npm run build.

CI runs the Python and web checks on every push. Pushing to main deploys dist/ to GitHub Pages.

License

MIT