Star System Seeder

A procedural solar system generator and browser-based renderer for a space colonization game. Runs entirely client-side — the deployed site on GitHub Pages is a static bundle.

Overview

Two components:

• Seeder — pure TypeScript that procedurally generates solar systems. Runs in the browser (bundled via esbuild) and as a Deno CLI for writing JSON seed files to disk.
• Renderer — vanilla JS + HTML pages for generating, browsing, and viewing systems (2D canvas and 3D Three.js).

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Local development

Requires Deno v2+.

deno task renderer

This builds the browser bundle (renderer/generator.bundle.js), starts a dev server at http://localhost:8080, opens your browser, and watches:

• renderer/ → triggers a browser reload on change.
• seeder/ → rebuilds the bundle, then triggers a reload.

CLI seeder (local only)

deno task seed [seed] [--json [folder]]

• Without arguments: generates a random system and prints stats.
• With an integer: generates that seed deterministically.
• --json: exports to seeds/ (or a folder you name).

Examples:

deno task seed
deno task seed 42
deno task seed 42 --json
deno task seed 42 --json ./exports

Tests

deno task test

One-shot build

deno task build

Produces renderer/generator.bundle.js. Rarely needed manually — the renderer task handles it.

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Deployment (GitHub Pages)

The site is deployed automatically on every push to main by .github/workflows/pages.yml.

One-time setup on a new repo: in Settings → Pages, set Source: GitHub Actions.

The deployed site is fully client-side:

• All system generation runs in the browser using the bundled seeder.
• Seeds are persisted to localStorage per origin. (The localhost origin and the github.io origin maintain separate libraries.)
• Routes are hash-based: seed.html#<seed>, canvas.html#<seed>. Sharing a seed URL is enough to reproduce the system — generation is deterministic from the seed.
• No server runs in production. The ./sse hot-reload endpoint fails silently there, which is intentional.

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Pages

Page	Purpose
index.html	Generator + scroll-snap library of seeds saved in localStorage
seed.html#<seed>	3D orrery view
canvas.html#<seed>	2D canvas view

Architecture

File	Role
seeder/generator.ts	Core generation logic — star, planets, moons, deposits
seeder/config.ts	Default config, archetype weights, settlement config
seeder/rng.ts	Seeded PRNG, name generator
seeder/types.ts	Shared TypeScript types
seeder/main.ts	CLI entry point (Deno only)
seeder/browser-entry.ts	Bundle entry — re-exports pure functions for the browser
build.ts	esbuild bundler, builds renderer/generator.bundle.js
server.ts	Local dev server (static + SSE + rebuild on seeder changes)
renderer/*.html	Page views
renderer/scene.js	3D orrery (Three.js)
renderer/canvas-scene.js	2D canvas orrery
renderer/panel.js, canvas-panel.js	System info panels
renderer/storage.js	localStorage wrapper
.github/workflows/pages.yml	CI: build + deploy to GitHub Pages

Seed files

The CLI writes to seeds/ by default; seeds/*.json is gitignored (the folder itself is tracked via .gitkeep). Commit specific files manually if you want to share them. The deployed site does not read these — only localStorage.