See also what’s new in Solaris lighting and rendering.

  • Overall improved performance and quality, including better motion blur, smooth polygon shading, and lower memory usage.

  • Close feature parity with Mantra.

  • Lens shader support and pre-made Physical Lens VOP with physical properties.

  • Motion blur now just works. You can use the USD instantaneousShutter render setting/display option to disable motion blur.

  • Improved adaptive sampling/variance anti-aliasing.

  • Controllable convergence mode. Path tracing mode give immediate feedback, for IPR. Distributed gives full controls over how many of each type of ray to send. Variance automatically chooses the number of indirect samples based on conditions.

  • Random Walk sub-surface scattering mode on Principled Shader VOP.

  • Native rendering of Houdini heightfields.

  • Higher quality fur rendering.

  • Improved ocean-surface rendering.

  • Karma now supports exports from displacement shaders.

  • Limited support for VEX trace function e.g. for rounded edge rendering. irradiance, not fully featured as in Mantra.

    Rounded edge comparison.
  • VEX importance_remap function for importance texture sampling.

  • Karma now supports Light path expressions including all USD features, extended light tags, BSDF labels, and primvars.

  • You can now override the light shader used to evaluate USD lights.

  • Shaders can now bind arbitrary primvars to shader imports.

  • Significant support for USD preview shaders. Preview shader VOPs (such as USD Preview Surface) now have shader exports (such as export_specularColor, export_emissiveColor, and export_metallic) you can use as AOVs.

  • Support for USD’s per-instance geometry and visibility overrides.

  • Karma now supports checkpointing so you can resume interrupted renders. See the Output Checkpoint Files parameter on the Output tab of the Karma LOP.

  • You can now click in the viewer/Mplay to target that area for progressive rendering.

  • Karma now supports Cryptomatte with AOVs. See how to set up Cryptomatte AOVs in Karma.

  • You can now output any primvar as an AOV. See the Image Output ▸ AOVs tab of the Karma LOP.

  • Karma now supports Ptex textures.

  • Karma now embeds extra useful metadata in OpenEXR output files (such as render settings). You can also specify custom metadata to add to the EXR file using parameters on the render node.

  • Simplified Karma LOP parameter UI.

  • AI-based denoising with Intel Open Image Denoise or the NVIDIA OptiX Denoiser available in the render delegate view, in a compositing node, and as a command line utility.

What’s new in Houdini 18.5