A browser-based tool for creating vector polygon graphics for games like Asteroids. Plot vertices on a snap-to-grid canvas and export as Lua flat arrays — ready to drop into LOVE2D or any Lua-based game engine.
- Click-to-place vertices on a configurable grid with snap-to-grid precision
- Drag vertices to reposition them after placement
- Mirror modes — reflect shapes across the X axis, Y axis, or both for symmetrical designs
- Rotation — live preview with slider or typed input, then apply to snap vertices to the grid
- Translate — move the entire polygon with arrow keys
- Close/open polygon — toggle the closing segment between first and last vertex
- Undo and clear — remove the last vertex or start over
- Editable Lua output — edit the Lua code directly and see changes reflected on the canvas
- Scale factor — multiply output coordinates by an integer scale (1–10)
- Copy to clipboard — one-click copy of the Lua table
No build tools, no frameworks, no dependencies. Just open the file in a browser:
open index.html
Or serve it locally with any static file server.
The editor exports vertices as a Lua flat array:
vertices = {
0, -4,
3, 2,
-3, 2,
}Paste this directly into your game code.
Pure logic is extracted into vector.js with a Node-based test suite:
node tests.js
index.html — Single-page app (HTML/CSS/JS)
vector.js — Pure logic module (shared between browser and tests)
tests.js — Test suite for all pure logic
use-cases/ — Alistair Cockburn fully-dressed use cases (UC-01 through UC-13)
CLAUDE.md — AI assistant project instructions
| Key | Action |
|---|---|
| Ctrl/Cmd+Z | Undo last vertex |
| Escape | Clear all vertices |
| C | Toggle close/open polygon |
| Arrow keys | Move polygon by 1 grid unit |
The use-cases/ directory contains 13 Alistair Cockburn fully-dressed use cases that document every feature's expected behavior. These are maintained alongside the code — any new feature or bug fix includes a corresponding use case review or update.
This project was built entirely with Claude Code.
MIT