Canvas-only 2D game editor/runtime built on PixiJS v8 + Vite + TypeScript. - core: asset model (Scene/Camera/Sprite), scene objects with sparse overrides, property schema + resolve, command stack (undo/redo), serialization and project store interface (16 unit tests) - ui: custom in-canvas widget toolkit (panels, fields, color picker, list/scroll, popup) with a hidden <input> keyboard bridge - editor: asset/hierarchy panels, schema-driven inspector, toolbar - viewport: box rendering, camera frame, selection gizmo, drag/zoom/pan - runtime: world/entity instantiation for play mode, input, camera follow - api: PHP JSON project store with revision counter (409 on conflict) - tools: CDP-based e2e smoke test Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
4.3 KiB
Game Maker
A browser-based tool "one step before a game engine": create assets (scenes, cameras, sprites), place them into scenes, tweak their properties in an inspector and press Play – all in one program, all drawn inside a single WebGL canvas.
Live: https://nockal.com/game-maker/ · Widget playground: https://nockal.com/game-maker/?playground
Concepts
| Term | Meaning |
|---|---|
| Asset | Named thing with a type (scene, camera, sprite) and typed properties. Assets have no position. |
| Scene object | An asset placed into a scene: a link to the asset + a position + sparse overrides of the asset's properties. Scenes cannot be placed. |
| Override | A per-object value that replaces the asset's value for one property. Only changed keys are stored; the inspector marks them bold and offers a reset (↺). |
| Edit mode | The viewport draws the project model; panels, grid, gizmos and drag-to-move are active. |
| Play mode | A World is instantiated from the active scene (one entity per scene object, resolved properties as mutable state). Systems tick it; nothing writes back. Stop discards the world. |
Phase-1 demo behaviour in Play: the arrow keys move the sprite that was selected when Play was pressed (or the first sprite); the first camera in the scene follows it.
Stack
- PixiJS v8 – rendering and pointer events. No game engine; runtime systems live in
src/runtime/. - Own canvas widget toolkit (
src/ui/) – panels, buttons, lists, text/number/color fields, popups. The only DOM element is a hidden<input>used as a keyboard bridge (IME, mobile keyboard, clipboard) while a canvas text field is focused. - Vite + TypeScript, Vitest for the pure core.
- PHP 8 JSON API (
api/) storing one JSON file per project indata/projects/, with atomic writes and an integer revision that rejects stale saves (HTTP 409).
Layout
web/index.html Vite source page (dev) index.html built page (generated, served)
src/core/ model, property schema, resolve, commands, store – no Pixi imports
src/runtime/ World, Entity, systems (Input, PlayerControl, CameraFollow)
src/ui/ widget toolkit (generic, knows nothing about assets)
src/viewport/ scene renderer: model in edit mode, world in play mode
src/editor/ App composition, state, panels, inspector field factory
api/ PHP backend data/projects/ persisted projects
tests/ Vitest unit tests tools/e2e.mjs headless CDP smoke test
Rules that keep it organised: core/ imports nothing from other layers; ui/ never sees
assets; position exists only on scene objects; overrides are merged in exactly one place
(core/properties/resolve.ts); the inspector is generated from PropertySchema – a new
property is one schema line.
Development
Node 22 is required (on this machine: PATH=/opt/node22/bin:$PATH).
npm install
npm run dev # http://localhost:5175/game-maker/dist/ – API calls are proxied to production
npm test # unit tests (core)
npm run typecheck
npm run build # writes dist/ and regenerates index.html
node tools/e2e.mjs <projectId> # headless end-to-end run with screenshots in /tmp/gm-e2e-*.png
The workspace folder itself is what nginx serves, so npm run build is the deployment.
API
All routes go through api/index.php?r=… (the site's nginx does not pass PATH_INFO).
| Method | Route | Body → Result |
|---|---|---|
| GET | projects |
[{id,name,revision,updatedAt}] |
| POST | projects |
{name} → project document (201) |
| GET | projects/{id} |
{id,name,revision,updatedAt,project} |
| PUT | projects/{id} |
{revision, project} → {revision,updatedAt} or 409 {revision} when stale |
| DELETE | projects/{id} |
204 |
There is no authentication yet; data/ is world-readable. Both are phase-2 topics.
Keyboard
Ctrl+Z / Ctrl+Shift+Z / Ctrl+Y undo/redo · Delete remove selection · Ctrl+Enter play ·
Esc stop · Tab cycles fields · number fields: drag to scrub (Shift ×10, Alt ×0.1),
↑/↓ step · viewport: wheel zooms, middle-drag or Shift+drag pans.
Out of scope for phase 1
Textures on sprites, physics, scripting, multi-select, z-order UI, auth, editing while playing, touch-optimised layout.