OTOY Forums

Posted: **Wed Oct 08, 2025 4:13 am**

This is a alpha release of the OctaneRender™ 2026.1.Alpha_3.3 for Houdini™ plugin compiled with the Octane 2026.1.Alpha 3 core. This 2026.1.Alpha_3.3 release is available for the latest Houdini production builds on Windows x64, Linux.

Houdini production builds supported by this release: 20.0.896, 20.5.613, 20.5.654, 20.5.684, 21.0.440.

If you are not sure if your Houdini version is compatible with the plugin - just run it and you will see an error message in case of incompatibility.

Linux Note
On Linux only default Houdini builds are supported.
This means that for Houdini 20.0, 20.5 and 21.0 gcc11.2 builds are supported.

New features
To learn more about the new features and improvements of OctaneRender 2026.1.Alpha 3, please check out the 2026.1.Alpha 3 release post

Known bugs
On Linux, MPlay IPR may not be working. If you are having problems with it, please switch to QT5 IPR and disable "Render to MPlay" in ROP nodes.

Downloads

Release 2026.1.Alpha_3.3 Studio+ license
Windows Houdini 20.0.896
Windows Houdini 20.5.613
Windows Houdini 20.5.654
Windows Houdini 20.5.684
Windows Houdini 21.0.440

Linux Houdini 20.0.896 (gcc11.2)
Linux Houdini 20.5.613 (gcc11.2)
Linux Houdini 20.5.654 (gcc11.2)
Linux Houdini 20.5.684 (gcc11.2)
Linux Houdini 21.0.440 (gcc11.2)
Release Notes
=============================================
RELEASE 2026.1.Alpha_3.3
=============================================
PLUGIN FEATURES AND FIXES:

Added "Distorted UVW" node
Supported new rgb image output color option
Supported pin/parameter folders to VOP/Material nodes
Avoid reloading unchanged polygon mesh object's geometry after scene frame changes
Fixed scatter on surface loading problems
Fixed Volume Ramp max vlaue parameter doesn't work
Added Volume to Texture node
Changed default log level to Error
createPackageFileForOctane.bat update: Added a section that checks for the old solaris.json file existence. If this is found, then it will ask to remove this file, as it can create issues, and WILL stop the plugin from working
Rendertarget and Rendersetup hda update: Updated the "ACES tone mapping" tooltip to remove version specific information (used to be 1.2 but will be changing version to version)
Reimplemented volume feature
1. New volume object parameters
2. Faster VDB grids loading
3. No more extra absorption and scatter grids after loading (meaning smaller memory size)
4. Set Voxel size correctly
5. Support extra grids like Cd grid
6. Support velocity vector grid
7. Fixed vdb volume sop level transform offset

OctaneRender for Houdini tutorial
Still updating

Note
From 2025.1.Beta_1.0, Octane plugin for Houdini uses Houdini package file. Each build ships a script (createPackageFileForOctane.bat for Windows, createPackageFileForOctane.sh for Linux and Mac) to help create the Octane.json file as below under C:\Users\<username>\Documents\houdiniXX.Y\packages on windows, ~/Library/Preferences/houdini/XX.Y/packages on Mac, or ~/houdiniXX.Y/packages on Linux.

Code: Select all

{
    "enable": true,
    "env": [
        {
            "OCTANE_AUTOSPAREPARAMS": {
                "value": 1
            }
        },
        {
            "OCTVERSION": "<path_to_plugin_directory>"
        },
        {
            "HOUDINI_PATH": {
                "value": "$OCTVERSION"
            },
            "HOUDINI_MENU_PATH": {
                "value": "$OCTVERSION/config/Menus"
            },
            "HOUDINI_SCRIPT_PATH": {
                "value": "$OCTVERSION/scripts"
            },
            "PATH": {
                "value": "$OCTVERSION/bin"
            },
            "PXR_PLUGINPATH_NAME": {
                "value": "$OCTVERSION/dso/usd_plugins"
            }
        }
    ]
}

Important Note
2024.1.0.2 fixed the problem that the layered material nodes cannot be loaded properly, however this fix affects all layered material nodes and OSL material nodes in existing saved .hip files. When loading a .hip file for the first time using this build, it's necessary to adjust the connections of these nodes. Once the file is saved with the updated connections, the issue will be resolved.

Common Issues and Solutions
- If the plugin doesn't work at all, set HOUDINI_DSO_ERROR = 2 in houdini.env and check for messages in the terminal.
- If you're missing libglut.so.3, install the freeglut package.
- If you are having any issues with the Deadline - please submit a support ticket to the AWS.

Happy rendering,
Your OTOY Team

Posted: **Wed Oct 08, 2025 12:07 pm**

NOTES ON THE VOLUMES: While we are working on improving these things there are currently some limitations to the Octane volumes implementation:
1. You can only have one volume set of grids per object (density, temperature, vel etc).
If you have multiple volumes please split them into seperate objects using an object merge.
2. Packed primitives & packed instances are not supported at the moment. For instancing use the instance obj node.
3. All grids need to have the same voxelsize, so mismatched grids (for ex. halfres velocity grids)
are not supported. You can use the vdb resample node using your density grid as a reference,
or disable resampling on the output tab of the pyrosolver node.
4. There is an issue with the volume motion blur, where you have to significantly increase
the velocity scale to get appropriate results.

We are working on improving these things. In the meantime one workaround for #3 and #4 is
to export your volume to a vdb file sequence using the file cache node and load it
using the vdb file mode. This should have better loading efficiency in some cases,
has accurate motion blur scale and supports mismatched grid resolutions.

OTOY Forums

OctaneRender 2026.1.Alpha 3 for Houdini Alpha (2026.1.Alpha_3.3)

OctaneRender 2026.1.Alpha 3 for Houdini Alpha (2026.1.Alpha_3.3)

Re: OctaneRender 2026.1.Alpha 3 for Houdini Alpha (2026.1.Alpha_3.3)