OptionalbaseOptionalbaseOptionalbaseOptionalbaseOren-Nayar diffuse roughness — reserved (v1 shades Lambert).
OptionalspecularOptionalspecularOptionalspecularOptionalspecularOptionalspecular[-1,1] tangent-aligned highlight stretch.
OptionalspecularAnisotropy direction in radians (tangent-space rotation).
OptionalcoatOptionalcoatOptionalcoatOptionalcoatOptionalcoatThroughput-darkening of the under-layer by the coat (0..1).
OptionalfuzzOptionalfuzzOptionalfuzzOptionalsubsurfaceBacklit-glow subsurface stand-in (engine model).
OptionalsubsurfaceOptionalthinOptionalthinOptionalthinOptionalemissionOptionalemissionOptionaltransmissionSee-through refractive transmission strength (OpenPBR transmission_weight /
glTF KHR_materials_transmission). Default 0 (opaque).
OptionalthicknessVolume thickness in world units (glTF KHR_materials_volume); drives
Beer-Lambert absorption. Default 0 (thin surface).
OptionalattenuationBeer-Lambert absorption color (glTF attenuationColor). Default white.
OptionalattenuationAbsorption distance (glTF attenuationDistance). Default Infinity (none).
OptionaldispersionChromatic dispersion (glTF KHR_materials_dispersion). Default 0.
OptionalopacityAlpha (geometry.opacity). Blended when transparent is set.
OptionalnormalOptionalunlitOutput base color with no lighting/IBL.
OptionalbaseOptionalnormalOptionalmetallicPacked metallic / emissive-scalar / roughness map (engine MER: R=metallic,
G=emissive scalar, B=roughness). Same layout as PbrMaterial.merMap.
OptionalemissivesRGB emission color texture; multiplied by emissionColor·emissionLuminance.
OptionalcoatTangent-space normal map for the clear-coat lobe (coat_normal). When absent
the coat uses the geometric normal (a smooth coat over a bumpy base — the
common car-paint case). Applied in the forward path only.
OptionalanisotropyAnisotropy direction/strength map (glTF KHR_materials_anisotropy
anisotropyTexture): .rg = the tangent-space direction (×2−1, rotated by
specularRotation), .b = a per-pixel strength multiplier for
specularAnisotropy. 1×1 default (dir (1,0), strength 1) when absent →
the constant rotation/strength path. Same layout as PbrMaterial.anisotropyMap.
OptionaltransmissionPer-pixel transmission factor map (glTF transmissionTexture, .r).
OptionalthicknessPer-pixel volume thickness map (glTF thicknessTexture, .g).
Optionaltransparent
OpenPBR Surface inputs (v1 subset). Defaults follow the OpenPBR spec's default surface where practical. Colors are linear RGB.