HtoA 6.4.6.1 - Arnold for Houdini

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

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

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