fix(viewer): guard TextureNode updates against null textures

[wass08]

Hotfix for the prod black-scene crash on project open (TypeError: Cannot read properties of null (reading 'matrix') in TextureNode.update).

three's override-material passes (shadow pass, depth/normal prepasses) copy each object's texture slots onto shared per-light/per-pass materials while caching per-mesh node graphs against those shared materials. When a cached graph contains a TextureNode for a slot the current base material doesn't provide, the per-frame reference pulls null and the exception aborts the whole render pass — one bad slot blacks out the scene.

This guards TextureNode.prototype.update (installed once at viewer module load): a null value skips the update with a throttled console warning instead of throwing. The affected slot renders textureless for a frame and recovers as soon as the reference pulls a real value. Root-cause investigation of the specific null slot is ongoing; this stops the bleeding for all variants of the class.

🤖 Generated with Claude Code

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Note

Medium Risk
Prototype-level monkey patch of three.js WebGPU node internals affects every texture update, but behavior is narrowly defensive; removing displacement-specific fallbacks shifts reliance entirely to this guard.

Overview
Fixes the production black-scene crash (Cannot read properties of null (reading 'matrix') in TextureNode.update) when override-material passes (shadow, depth/normal prepass) leave a cached node graph pointing at a texture slot the current material no longer provides.

Adds installTextureNodeNullGuard(), invoked at viewer module load before any node materials build. It patches TextureNode.prototype.update so a null value is swapped for a shared 1×1 black DataTexture (with throttled warnings) before the original update runs—skipping alone is insufficient because null still breaks backend texture binding.

Removes the earlier materials.ts workaround: neutral displacement textures on every MeshStandardNodeMaterial, ensureDisplacementFallback, and clearedSlotValue. Texture clearing and cold-load paths again set slots to null and trigger needsUpdate to rebuild graphs, relying on the guard for safety across all texture slots, not only displacement.

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Cursor Bugbot has reviewed your changes using high effort and found 2 potential issues.

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[cursor]

Update patch drops frame argument

Medium Severity

The TextureNode.prototype.update wrapper doesn't forward the frame argument to the original update function. While three's node runtime invokes update(frame), the original implementation always receives undefined for frame, breaking frame-dependent texture updates like video textures.

 

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[cursor]

Fallback assignment can stick on node

Medium Severity

When value is null, the guard writes the shared fallback onto this.value and leaves it there. Recovery assumes a reference will overwrite it later; if that pull is skipped or only runs on material changes, the node keeps sampling the 1×1 black texture after a real map is available, or keeps a fallback where the slot should stay empty.

 

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