Matter.js Skill

Workflow

• Confirm environment (plain HTML, React, or canvas-only) and rendering approach (Matter.Render for debug vs custom renderer).

• Provide a minimal Engine/World/Render/Runner setup and add bodies.

• Add interactions (mouse constraint) or constraints only if requested.

• Share cleanup steps for SPA or teardown scenarios.

Minimal setup

<script> const { Engine, Render, Runner, Bodies, Composite } = Matter;

const engine = Engine.create();

const render = Render.create({ element: document.body, engine: engine, options: { width: 800, height: 600, wireframes: false } });

const runner = Runner.create(); Runner.run(runner, engine); Render.run(render);

const ground = Bodies.rectangle(400, 610, 810, 60, { isStatic: true }); const box = Bodies.rectangle(400, 200, 80, 80);

Composite.add(engine.world, [ground, box]); </script>

Common patterns

• Use Composite.add(engine.world, [...]) to add bodies to the world.

• Use Render.create({ element, engine }) to create a canvas automatically, or pass a canvas you create yourself.

• Set render.options.wireframes = false for solid rendering.

• Use Runner.run(runner, engine) for a simple loop, or call Engine.update in your own loop if you need custom timing.

Mouse interaction (optional)

const { Mouse, MouseConstraint } = Matter; const mouse = Mouse.create(render.canvas); const mouseConstraint = MouseConstraint.create(engine, { mouse }); Composite.add(engine.world, mouseConstraint); render.mouse = mouse;

Cleanup checklist (SPA)

• Stop the runner with Runner.stop(runner) .

• Remove the render canvas from the DOM.

• Clear engine and world if needed.

Questions to ask when specs are missing

• What viewport size and scaling should the canvas use?

• Are we using Matter.Render or a custom renderer?

• Do you want mouse/touch drag interaction?

• Should the simulation loop be paused when offscreen?