editor-ui

A set of rules for separating an editor's React interface from its core state and operations. React is the library used to display the editor panels; the editor core owns scene data, selection, assets, undo, and saving.

In plain words
What is it for?
Use it when editing editor panels, selection, viewport tools, asset workflows, scene changes, or undoable interactions in the editor.
Why use it?
Keeping scene data inside UI components can cause inconsistent state and make undo, saving, and rendering unreliable. The rules keep panels as views and route changes through the editor core.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/andvolodko/html5-game-editor/editor-ui
Clone the repo
git clone --depth 1 https://github.com/andvolodko/html5-game-editor

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 669 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00669
Opus 5 $0.00000 $0.00334
Sonnet 5 $0.00000 $0.00134
Haiku 4.5 $0.00000 $0.00067

Measured 2d ago against content hash 1782a758c1e0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

editor-ui scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/editor-ui.mdc · 36 lines

How it starts

The opening of the file, as written. The whole thing — 36 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Editor UI / editor-core

Canonical scene and editor state lives in Editor (DocumentManager, SelectionManager, CommandManager, AssetManager, EditorViewportController). React is a view layer.

Separation

  • React must not own scene trees, transforms, or asset catalogues as source of truth. Read via useEditor / useEditorState; mutate via Editor / commands / workflows (importDroppedFiles, dropAssetOntoScene).
  • Do not call document/scene mutators from components except through editor.execute, editor.createSprite*, editor.setTransform2D, editor.saveScene / loadScene, or exported workflows.
  • Do not mutate PIXI.DisplayObject / THREE.Object3D from React. Viewport tools (e.g. bindPixiTransformTool) map renderer pointer callbacks → editor.selectNodes / editor.setTransform2D. Preview-only motion may update the renderer; commit one command on gesture end.
  • Keep application policy in packages/editor-core (commands, asset workflows, browser folder helpers). Keep panels thin: HierarchyPanel, InspectorPanel, AssetsPanel, ScenePanel, Toolbar.

Selection, layout, assets

  • Node selection is stable node IDs in SelectionManager — never store PIXI/THREE objects in selection.
  • Asset Browser selection (selectedAssetId, search, currentFolder) may stay UI-local; do not confuse it with scene selection. Import destination should follow the browser folder model (ASSETS_ROOT_FOLDER, listAssetsInFolder, …).
  • Docking (DockLayout / dockview) is layout-only; it must not become domain state.

React performance and lifecycle

  • Prefer useEditorState(selector) so panels re-render from Editor revision/selection, not copied scene graphs in React state.
  • Do not push per-frame drag positions through React state. Drag preview stays in PixiSceneRenderer.previewNodePosition; undoable update is one SetTransform2DCommand on pointer-up.
  • Every editor.subscribe / selection.subscribe / assets.subscribe / setPointerHandlers / attachRenderer must be disposed in the same scope (effect cleanup).
  • PixiSceneRenderer: construct in ScenePanel effect; on teardown call unbindTool, editor.detachRenderer, and renderer.destroy(). Pass AssetResolver (editor.assets), not ad-hoc FS paths.
  • Inspector drafts (string inputs) are UI-only until blur/Enter commits a command. Display size on sprites is a scene override, not live asset metadata.

Read the full file on GitHub · 36 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 36 lines · 0 tokens per session scan A 1782a758c1e0

Subscribe to this mod's changes

editor-ui is a cursor rule published in the GitHub repository andvolodko/html5-game-editor (5 stars, last pushed 8d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 669 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.