HtoA 6.4.6.1

19 February 2026

HtoA 6.4.6.1 is a bugfix release using Arnold 7.4.5.1. For the full list of features in HtoA 6.4.6.0, see the HtoA 6.4.6.0 release notes.

Installation

• Download Arnold for Houdini from your Autodesk Account. See Download Arnold for more information about downloading HtoA from your Autodesk Account.

• Follow these installation instructions

Bug Fixes

• HTOA-3126 - Houdini 21: overscan does not work with raster product type
• ARNOLD-17399 - IPR crash after deleting shapes
• ARNOLD-17489 - Crash with invalid vdb points grid in point cloud queries
• ARNOLD-17494 - Linux crash regression in 7.4.5.0
• usd#2557 - Fix regression when a geometry has an instancer without any instances
• usd#2547 - Changing material terminal is not updated with Hydra 2
• usd#2536 - ArnoldUsd procedural filename is not reported as an asset
• usd#2561 - Fix regression in husk with dataWindow NDC

System Requirements

• Houdini, Houdini FX, Houdini Indie and Houdini Education

  • 20.0.896
  • 20.5.684
  • 21.0.596

• Linux with at least glibc 2.17 and libstdc++ 11.2.1 (gcc 11.2.1) for Houdini 20/20.5. This is equivalent to Rocky 8.

• macOS 11 or later

• Apple Mac models with M series chips are natively supported by HtoA

• x86-64 CPUs need to support the SSE4.1 instruction set. Apple Mac models with M series chip are supported natively mode.

• GPU rendering works on Windows and Linux only and requires driver versions newer than 582.16/580.126 (Windows/Linux). Older drivers will log an error and abort the render. Note that you can use New Feature Branch drivers.

  • On Linux, we recommend 590.48 or higher drivers.
  • On Windows, we recommend 591.28 or higher drivers.

• Optix™ denoiser requires an NVidia GPU with CUDA™ Compute Capability 5.0 and above.

• Intel OIDN GPU support is limited to:

  • MacOS
    • Apple native CPUs (M1 and newer)
  • Windows
    • Intel Xe dedicated and integrated GPUs
    • NVIDIA GPUs using Turing or newer architectures