Wassim SAMADandClaude Opus 4.7
11015ea1ed
Captures the gotchas surfaced while building the shelf so the next
contributor adding a registry-driven kind doesn't rediscover them.
`node-definitions.md` — new Pitfalls section + a rule that builders
must emit local-space children. Covers:
- `<GeometrySystem>` must NOT mutate `group.position` / `group.rotation`
after rebuild (the renderer binds them via JSX prop).
- Tag geometry-built children with `userData.__fromGeometry` so
rebuilds don't dispose React-mounted hosted children (the
item-disappears-on-shelf bug).
- Previews must clone materials before mutating them when the kind's
builder caches at module scope.
- Host kinds need a `children: z.array(...).default([])` field on their
schema (and a migration patch for older scenes).
`tools.md` — three new move/placement pitfalls:
- Disable raycast on the moved mesh during drag, otherwise it captures
the ray and starves `grid:move` → commits land at the stale start.
- Commit handlers listen to `grid:click` AND every `${kind}:click` to
catch clicks that land on neighbouring 3D geometry first.
- Move tools must preserve the node's actual `rotation[1]` in
`useLiveTransforms` — hardcoding 0 makes the node un-rotate mid-drag.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
214 lines
14 KiB
Markdown
214 lines
14 KiB
Markdown
# Node definitions
|
|
|
|
*The registry-driven composition model for node kinds.*
|
|
|
|
Applies to: `packages/core/src/registry/`, `packages/nodes/src/<kind>/`, `packages/viewer/src/components/viewer/{registered-systems.tsx,node-renderer.tsx}`.
|
|
|
|
A *node kind* — shelf, wall, door, item, spawn, zone — is described by a `NodeDefinition` registered with `nodeRegistry`. The definition is plain data + lazy module references. Three optional fields decide how the kind appears in the scene at runtime; pick whichever combination matches the kind's needs.
|
|
|
|
This page covers those three fields. For the broader registry contract (schemas, capabilities, parametrics, MCP), see [the registry plan](../../../plans/editor-node-registry.md) in the private repo.
|
|
|
|
## The three-checkbox model
|
|
|
|
| Field | Purpose | Pick it when |
|
|
|---|---|---|
|
|
| `geometry?: (node, ctx) => Object3D` | Pure builder. Returns the meshes for this node. | The kind has parametric meshes that should rebuild when `updateNode` runs. |
|
|
| `renderer?: () => Promise<{ default: ComponentType<{ node }> }>` | Optional custom React component. Owns mesh creation. | The kind needs JSX-only features: `<Html>`, `useGLTF`, drei helpers, instancing, TSL shader materials, R3F portals. |
|
|
| `system?: () => Promise<{ default: ComponentType }>` | Optional per-frame component (`useFrame` returning `null`). | The kind needs imperative work per frame: animations, opacity transitions, named-mesh material poking, cross-kind dirty cascades. |
|
|
|
|
The three fields are **independent**. There is no discriminator tag — presence is participation:
|
|
|
|
```ts
|
|
// shelf — pure geometry, no React, no per-frame work
|
|
export const shelfDefinition: NodeDefinition<typeof ShelfNode> = {
|
|
// ...
|
|
geometry: buildShelfGeometry, // pure function in geometry.ts
|
|
}
|
|
|
|
// zone — built once via React (uses <Html>), animated per-frame via system
|
|
export const zoneDefinition: NodeDefinition<typeof ZoneNode> = {
|
|
// ...
|
|
renderer: () => import('./renderer'), // composes <Html> + TSL materials
|
|
system: { module: () => import('./system') }, // pokes uniforms per frame
|
|
}
|
|
|
|
// door — pure geometry + animation system
|
|
export const doorDefinition: NodeDefinition<typeof DoorNode> = {
|
|
// ...
|
|
geometry: buildDoorGeometry,
|
|
system: { module: () => import('./animation') }, // advances operationState
|
|
}
|
|
```
|
|
|
|
## Runtime: how the three fields are wired
|
|
|
|
Two framework components live in `packages/viewer/src/components/viewer/`:
|
|
|
|
- **`<NodeRenderer>`** chooses what React mounts for a node:
|
|
1. If `def.renderer` is set → mount the custom renderer.
|
|
2. Otherwise → mount `<ParametricNodeRenderer>` — a thin empty `<group>` that registers with `sceneRegistry`, attaches pointer handlers via `useNodeEvents`, reads `useLiveTransforms` for drag overrides, and calls `useScene.getState().markDirty(node.id)` on mount.
|
|
- **`<GeometrySystem>`** runs every frame:
|
|
1. Read `dirtyNodes` from `useScene`.
|
|
2. For each dirty node whose kind has `def.geometry`, look up the registered `Group` from `sceneRegistry`, build a `GeometryContext`, call `def.geometry(node, ctx)`, dispose old children, attach the new ones, call `clearDirty(id)`.
|
|
3. Kinds with no `def.geometry` are skipped — their custom `def.renderer` handles geometry on its own.
|
|
|
|
Per-kind `def.system` components mount alongside via `<RegisteredSystems>`. They run their own `useFrame` and can mark nodes dirty, address meshes by `getObjectByName`, advance animation state, etc. They run **in addition** to `GeometrySystem`, not instead of it.
|
|
|
|
## `GeometryContext`
|
|
|
|
The second arg to `geometry()` is scene read access for builders that reference other nodes by ID. Most kinds ignore it.
|
|
|
|
```ts
|
|
type GeometryContext = {
|
|
resolve: <N = AnyNode>(id: AnyNodeId) => N | undefined
|
|
children: AnyNode[] // resolved children of this node
|
|
siblings: AnyNode[] // same kind, same parent (drives wall mitering)
|
|
parent: AnyNode | null
|
|
}
|
|
```
|
|
|
|
- **Shelf, spawn, item, column, fence segment** — builder reads only `node`. `ctx` argument unused.
|
|
- **Wall** — `ctx.siblings` for corner mitering with adjacent walls. `ctx.children` for cutout footprints (doors / windows hosted on the wall).
|
|
- **Door / window** — `ctx.parent` for parent-wall thickness, so the frame depth lines up with the wall it's cut into.
|
|
|
|
`GeometryContext` exists so builders stay pure (no `useScene` import, no store mutation) and trivially unit-testable. The generic `<GeometrySystem>` builds `ctx` from the current scene snapshot once per dirty node; the cost is a few `Map.get` calls.
|
|
|
|
For level-scoped batch data (wall mitering across an entire level), `ctx` can be extended with `ctx.levelData?.miters` in a future revision — decided alongside the wall migration (Phase 3 of the registry plan).
|
|
|
|
## Choosing the right combination
|
|
|
|
### `geometry` only
|
|
|
|
Use this when the kind's meshes are a pure function of its node data. **Shelf, spawn, item, column, fence segment, wall, door (geometry side), window (geometry side).**
|
|
|
|
```ts
|
|
// packages/nodes/src/shelf/geometry.ts
|
|
export function buildShelfGeometry(node: ShelfNode): Group {
|
|
const group = new Group()
|
|
group.add(buildTopBoard(node))
|
|
group.add(buildBracket(node, -1))
|
|
group.add(buildBracket(node, +1))
|
|
return group
|
|
}
|
|
|
|
// packages/nodes/src/shelf/definition.ts
|
|
export const shelfDefinition: NodeDefinition<typeof ShelfNode> = {
|
|
// ...
|
|
geometry: buildShelfGeometry,
|
|
}
|
|
```
|
|
|
|
No renderer.tsx, no system.tsx. The generic renderer mounts an empty group, the generic system fills it.
|
|
|
|
### `renderer` only (no `geometry`, no `system`)
|
|
|
|
Use this when the kind composes its scene via JSX-only features and never needs imperative per-frame work. **GLB-backed items, kinds that mount drei helpers.**
|
|
|
|
```tsx
|
|
// packages/nodes/src/<kind>/renderer.tsx
|
|
import { useGLTF } from '@react-three/drei'
|
|
import { useRegistry } from '@pascal-app/core'
|
|
import { useNodeEvents } from '@pascal-app/viewer'
|
|
|
|
const FurnitureRenderer = ({ node }: { node: FurnitureNode }) => {
|
|
const ref = useRef<Group>(null!)
|
|
const { scene } = useGLTF(node.asset.url)
|
|
const handlers = useNodeEvents(node, 'furniture')
|
|
useRegistry(node.id, 'furniture', ref)
|
|
return <primitive object={scene.clone()} ref={ref} {...handlers} />
|
|
}
|
|
```
|
|
|
|
No `def.geometry` — geometry is the GLB. No `def.system` — there's nothing to animate.
|
|
|
|
### `renderer` + `system` (no `geometry`)
|
|
|
|
Use this when the kind's tree contains React-only primitives (e.g. `<Html>`) and needs per-frame imperative work that doesn't rebuild geometry. **Zone.**
|
|
|
|
The renderer composes the tree once. The system pokes uniforms / opacity / transforms by name:
|
|
|
|
```tsx
|
|
// renderer.tsx
|
|
<group ref={ref} {...handlers}>
|
|
<Html name="label" position={centroid}>{node.name}</Html>
|
|
<mesh name="floor" geometry={floorGeometry} material={floorMaterial} />
|
|
<mesh name="walls" geometry={wallGeometry} material={wallMaterial} />
|
|
</group>
|
|
|
|
// system.tsx
|
|
useFrame(() => {
|
|
sceneRegistry.byType.zone.forEach((id) => {
|
|
const group = sceneRegistry.nodes.get(id) as Group
|
|
const walls = group.getObjectByName('walls') as Mesh
|
|
const material = walls.material as MeshBasicNodeMaterial
|
|
material.userData.uOpacity.value = lerp(currentOpacity, targetOpacity, lerpSpeed)
|
|
})
|
|
})
|
|
```
|
|
|
|
### `geometry` + `system`
|
|
|
|
Use this when the kind has parametric geometry **and** extra responsibilities. **Door, window.**
|
|
|
|
- `geometry` builds the visible meshes (frame, panels, hardware) as a pure function of node state + parent wall.
|
|
- `system` advances animation (`operationState`), then calls `markDirty(node.id)` so the geometry system rebuilds on the next frame.
|
|
|
|
This split keeps animation state outside the node schema (it's ephemeral — lives in `useInteractive`) while still re-using the generic rebuild path.
|
|
|
|
## Named meshes work in either pattern
|
|
|
|
Setting `mesh.name = 'walls'` is just a three.js property. A system targeting `getObjectByName('walls')` doesn't care whether the mesh was created in JSX (`<mesh name="walls" />`) or imperatively in a pure builder (`mesh.name = 'walls'; group.add(mesh)`). Use whichever fits the kind.
|
|
|
|
## Migrating from custom renderer+system files to `def.geometry`
|
|
|
|
If your kind's current system *only* rebuilds geometry on dirty (no animations, no cascades, no material poking), it can collapse to a single `def.geometry` function:
|
|
|
|
1. Extract the imperative `updateXMesh(node, group)` from the system into a pure `buildXGeometry(node): Group` in `packages/nodes/src/<kind>/geometry.ts`.
|
|
2. Replace `def.renderer` with nothing — the framework's `<ParametricNodeRenderer>` covers it.
|
|
3. Replace `def.system` with `def.geometry: buildXGeometry`.
|
|
4. Delete `renderer.tsx` and `system.tsx`.
|
|
|
|
If the system also handles cascades, animations, or material updates, keep `def.system` and *also* set `def.geometry` — they run side by side.
|
|
|
|
## Rules
|
|
|
|
- **Builders must be pure.** No `useScene` import inside a `def.geometry` function. Read scene state via `ctx`. Mutating the store from a builder breaks idempotence.
|
|
- **Builders emit local-space children.** The registered `<group>` is positioned/rotated by `<ParametricNodeRenderer>` via JSX (`position={liveTransform?.position ?? node.position}`). Builders return geometry as if the parent were at the origin — never bake the node's world position into vertex coords.
|
|
- **One mesh registered per node ID.** The generic renderer registers a single `<group>` per node. If a custom renderer mounts multiple meshes, register the parent group (or whichever object the system needs to address).
|
|
- **Custom systems run in addition to the generic system, not instead of it.** A kind with `def.geometry` + `def.system` will see the generic system rebuild children on dirty AND the per-kind system run its `useFrame`. Plan priorities accordingly: door-animation runs at priority 2, geometry rebuild at priority 3.
|
|
- **Dispose on rebuild.** The generic system disposes the previous children's geometry + material before swapping. Custom systems that imperatively add children must dispose what they replace, or accept the GPU-memory cost.
|
|
- **`def.renderer` overrides the generic renderer.** Once you set it, you own the mount — `<ParametricNodeRenderer>` is not invoked. The generic geometry system still runs for the kind if `def.geometry` is set, so a custom renderer can register an empty group and let the system fill it.
|
|
|
|
## Pitfalls
|
|
|
|
### `<GeometrySystem>` must not mutate `group.position` / `group.rotation`
|
|
|
|
`ParametricNodeRenderer` binds `<group position={liveTransform?.position ?? node.position}>` and the matching rotation via JSX. React only re-applies the prop when its underlying value changes. If the geometry system imperatively zeroes `group.position` after a rebuild — as legacy per-kind systems used to — R3F has no reason to re-render on the next tick and the group stays at the origin. Symptom: the node visually snaps to `(0, 0, 0)` whenever its geometry rebuilds (move commit, dimension change, paint).
|
|
|
|
The contract is the other way around now: builders produce local-space children; the renderer owns the transform; the system only swaps children.
|
|
|
|
### Tag geometry-built children with `userData.__fromGeometry`
|
|
|
|
A registered `<group>` can host **two** kinds of children: meshes the geometry builder created (boards, posts, dividers) and React-rendered hosted nodes (items reparented onto a shelf surface). When the system rebuilds, it must dispose only the previous geometry pass — disposing React-mounted children would tear out their meshes mid-mount, leaving the hosted node in scene state but invisible. Symptom: dragging an item onto a shelf makes the item disappear and never come back.
|
|
|
|
`<GeometrySystem>` tags every child returned by the builder with `userData.__fromGeometry = true` and `disposeChildren` only removes/disposes children carrying the marker. Custom systems that imperatively add children to a registered group must follow the same convention if hosted children are possible.
|
|
|
|
### Previews must clone materials before mutating them
|
|
|
|
`def.preview` typically calls the kind's geometry builder, then walks the resulting meshes and sets `material.transparent = true; material.opacity = 0.5` for a ghosted look. If the builder caches materials at module scope — and shelf, item, and most cache-friendly kinds do, keyed on `material` / `materialPreset` — every committed instance of the kind in the scene shares one material instance. Mutating it in the preview leaks the translucency into every real node that uses the default material; placed shelves render see-through, placed items lose their opacity, etc.
|
|
|
|
The fix is to clone in the preview, mutate the clone, and reassign `mesh.material` to the clone. On unmount, dispose only the clones — **never** the original returned by the builder, which other nodes still reference. `nodes/src/shelf/preview.tsx` is the reference implementation.
|
|
|
|
### Host kinds need a `children` field on the schema
|
|
|
|
If your kind declares `relations.hosts: [...]`, add `children: z.array(...).default([])` to the schema. `useScene.createNode(child, parentId)` writes `child.parentId = parentId` **and** appends `child.id` to `parent.children`. Without the field, the parent-side write is a no-op — `<ParametricNodeRenderer>`'s `n.children.map(...)` then has nothing to mount and the host renderer never sees the new child. Symptom: hosted node lives in `useScene.nodes` but no React mount fires, so the host's tree-node sidebar entry is empty and the 3D scene shows nothing where the host should pick it up.
|
|
|
|
Migrations matter: if your kind shipped before hosting was added, patch existing nodes in `migrateNodes` so `Array.isArray(node.children)` holds for every loaded scene before the renderer reads it.
|
|
|
|
## See also
|
|
|
|
- [renderers.md](renderers.md) — the legacy renderer pattern (still authoritative for kinds with custom `def.renderer`).
|
|
- [systems.md](systems.md) — per-kind systems, frame-priority ordering, and core/viewer split.
|
|
- [scene-registry.md](scene-registry.md) — how `sceneRegistry` indexes nodes by ID and type.
|
|
- [Node registry plan](../../../plans/editor-node-registry.md) *(in private-editor)* — the multi-phase migration that produced this model.
|