MDL SDK 2021.0.2 (344800.7839): 07 Oct 2021

ABI compatible with the MDL SDK 2021.0.2 (344800.7839) binary release
(see https://developer.nvidia.com/mdl-sdk)

Added and Changed Features

• MDL SDK examples

  • Example DXR
    • Added support for various glTF extensions to the example renderer and the MDL support
      module. The new supported extensions are: KHR_texture_transform,
      KHR_materials_transmission, KHR_materials_sheen, KHR_materials_specular,
      KHR_materials_ior, and KHR_materials_volume.
    • Added support for state::animation_time() when the animation mode is enabled in the
      renderer settings.
    • Added support for volume attenuation to the renderer.
    • Update MaterialX dependency to version 1.38.1.

Fixed Bugs

• MDL Compiler and Backends

  • Fixed incorrect BSDF evaluation for df::sheen_bsdf with a transmitting "multiscatter"
    BSDF parameter.
  • Fixed df::thin_film implementation for the case material IOR < thin film IOR
    (libbsdf).
  • Creation of compiled materials fails now (instead of crashing) if some internal error
    condition is detected.

• MDL SDK examples

  • Example DXR
    • Fixed the UV coordinate transformations to match the glTF specification. Now the
      V-coordinate is simply flipped by applying v = 1.0f - v to improve UDIM support.
    • Metallic-roughness texture lookups are fixed and will now be handled strict to the glTF
      specification.