Redshift Compatibility Notice: Hydra 2.0 in Houdini 21

Starting with Houdini 21, SideFX has implemented Hydra 2.0 as the new default interface for render delegates. However, the current version of Redshift is not yet compatible with this new Hydra 2.0 architecture.

If you're using Redshift with Houdini 21's Solaris, you'll encounter compatibility issues unless you disable Hydra 2.0.

Required Workaround
To use Redshift with Houdini 21, you must disable Hydra 2.0 by adding the following environment variable to your Houdini configuration:

USDIMAGINGGL_ENGINE_ENABLE_SCENE_INDEX=0

Where to add this:

Add this line to:

•  Your houdini.env file (located in your Houdini preferences folder)
• Or include it in your Houdini package configuration file

Maxon is working on Hydra 2.0 compatibility for Redshift, which is expected to be available in early 2026. Once the updated Redshift version is released, you'll be able to remove this environment variable and take full advantage of Hydra 2.0's improvements.

This limitation only affects Houdini 21. If you're using Houdini 20.x or earlier versions, no configuration changes are needed.