HtoA 6.4.4.1
24 September 2025
HtoA 6.4.4.1 is a bugfix release using Arnold 7.4.3.2. For the full list of features in HtoA 6.4.4.0, see the HtoA 6.4.4.0 release notes.
Important: The Arnold 7.4.3.x releases are the last Arnold releases that will include support for CentOS 7.
Bug Fixes
- HTOA-2996 - Volume LOP does not work with step_scale
- ARNOLD-16506 - Cryptomatte filter was not reflecting interactive changes in the beauty filter
- ARNOLD-16695 - MaterialX Color4 Image node throws error while rendering
- ARNOLD-16713 - Support normalmap shaders from older versions of materialx
- ARNOLD-16723 - Support materialx_types in AiMaterialxGetNodeEntryFromDefinition
- ARNOLD-16761 - Crash when largest polygon stats contains deleted mesh
- ARNOLD-16770 - Scene bounding box is not updated for changes that reinitialize a geometry node
- ARNOLD-16772 - Nested procedural instances randomly disappear when GPU rendering on Linux
- usd#2422 - Fix regression on frame changes in the usd procedural
Installation
System Requirements
Houdini, Houdini FX, Houdini Indie and Houdini Education
- 20.0.896
- 20.5.684
- 21.0.440
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 and OptiX denoising work on Windows and Linux only, and require an NVIDIA GPU with the Maxwell architecture or later.
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
- AMD GPUs with RDNA2 (Navi 21 only) and RDNA3 (Navi 3x) architectures