A graph that reads an optional value needed a chain of Equals and
Branch just to fall back on a default. The new node does that in one
step: it passes a through unless a is empty, in which case b comes
out. Both ports are any, so it works for numbers, text, lists,
structs and objects alike.
- `First not empty` sits in the data category with two any inputs
`a` and `b` and one any output `value`. Are both empty, b comes
out, so the second input doubles as the default.
- `isEmptyValue` in values.ts holds the rule as a pure function:
nothing connected, 0, an empty text, false, an empty list, and a
struct whose fields are all empty.
- The struct case is what covers a position: behavior graphs have no
vector type of their own, so (0, 0) arrives as a struct. `{x: 0,
y: 2}` therefore counts as set, `{x: 0, y: 0}` as empty.
Findings:
- A real 0 or false on a is passed over. That follows from counting
0 as empty and is written down in the issue.
- The output stays any. Ports that inherit their type from an input
do not exist in the graph; `Item at` has the same shape.
Tests:
- ./check.sh: 142 files, 2104 tests, exit 0 (was 2094).
- 10 new catalog cases: a set, a unconnected, 0, "", false, an empty
list, a position (0, 0), a struct with one field set, an object,
and both empty.
- Counter-check: with structs never empty and 0 a real value exactly
those two cases fail, the rest stays green. Originals restored and
compared with cmp, then rebuilt.
- No e2e check: single data nodes have no e2e coverage here, the
palette fills itself from BUILT_IN_NODES.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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
The documentation is the wiki: https://git.nockal.com/meleki/game-maker/wiki – every concept, node, tab and shortcut, plus the architecture and the development workflow. This file is the short way in.
In one screen
- An asset is a named, typed thing (scene, camera, sprite, text, behavior, collider, rigidbody, container, texture, font, sound, animation, state machine, shader, particles, variables, tile, tilemap) with properties and no position.
- A scene object places an asset: position, sparse overrides of its properties, an optional parent. Only what differs from the asset is stored; the inspector paints it gold and offers ↺ / ↑.
- A container is a reusable group edited once and placed many times; its content is resolved from the template on every read. A screen is a container switched on and off.
- A behavior is logic as a node graph, placed like anything else and parented to the object it acts on. Play has no built-in behaviour – everything that happens is a graph.
- An account owns projects: the editor asks for a user name and a password first, and each account sees only its own projects. The Account menu at the far right of the toolbar changes the password and signs out.
- Play runs a throwaway copy of the project; every panel stays usable and Stop brings back exactly what was saved.
Quick start
Node 22 is required.
npm install
npm run dev # http://localhost:5175/game-maker/dist/ – API calls are proxied to production
npm run check # typecheck + lint + format:check + unit tests – the gate CI runs too
npm run build # writes dist/ and regenerates index.html; the folder is what nginx serves
The browser suite and the three example games need a machine with a GPU:
node tools/seed-e2e.mjs && node tools/e2e.mjs # the editor, 1293 checks (GM_STEPS=20 for one step)
# every tool signs in first – see the Accounts page
node tools/seed-jumprun.mjs && node tools/smoke-jumprun.mjs
node tools/seed-tetris.mjs && node tools/smoke-tetris.mjs
node tools/seed-actor.mjs && node tools/smoke-actor.mjs
Every push runs all of it on the Gitea runner – the gate as one job, build and suite as another beside it – so locally take the gate plus the step your change touches and leave the full run to CI. Details, the GPU requirement and the detached runner are in Development.
Documentation
| Page | What it covers |
|---|---|
| Concepts | Assets, scene objects, overrides, play mode, the camera, the console |
| Accounts | Signing in and out, the accounts, who a project belongs to, what the check tools need |
| Scenes | The edited scene, the start scene, and switching scenes from a graph |
| Scene editing | Placing, z-order, hierarchy, the editor offset |
| Behaviors | Node graphs: variables, the node set, structs and lists, loops, nesting, editing |
| Colliders | Shapes (box, circle, capsule, polygon), collision events, blocking movement, one-way colliders and raycasts |
| Physics | Rigidbodies, the collider material, gravity, the fixed step |
| Textures | Images, frames, nine-slice, the filter, upload limits |
| Fonts | Font assets, the picker, what a text falls back to |
| Sounds | Sound assets and Play sound |
| Animations | Animation assets and the Animation tab |
| Shaders | Shader graphs a sprite wears, their node set, the properties they declare |
| Particles | Particle graphs: a particle as a function of its age |
| State machines | The asset, named transitions, State branch, Set state and State transition |
| Containers | Templates, instances, screens |
| Tiles | The tile asset, plain tiles and the two autotile kinds, the pictures as animation steps, the Tile tab |
| Tilemaps | The tilemap asset, painting in the scene view, layers, what it looks like in the game |
| Plugins | Extending the editor: the plugin file, how it is loaded, switching one on and off, API v1 |
| Keyboard | Every shortcut |
| Architecture | Stack, source layout, the rules that keep it organised |
| Development | Commands, the e2e suite, the example games, CI |
| API | The PHP JSON API and the project document |
Ideas, gaps and bugs
They live in the issue tracker: https://git.nockal.com/meleki/game-maker/issues. What is not there yet is listed on the wiki's Home page.
