Procedural Materials

Build a cause graph, not a collection of channel effects:

stable coordinates -> structural causes -> identity weights
  -> causal modifiers -> filtered microstructure
  -> NodeMaterial PBR slots -> final-image owner

Use MeshStandardNodeMaterial for standard opaque/emissive PBR and MeshPhysicalNodeMaterial only when its extra lobes or transport properties are part of the surface. Keep Three.js lighting, environment, shadows, and energy handling by assigning node slots instead of replacing the whole fragment output.