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Houdini

Houdini 22 two months in, with production build 22.0.429 and Houdini Engine for Unreal 4.0.1

Houdini 22 is on its first production-build update, Houdini Engine for Unreal 4.0.1 targets it, and HIVE Equinox just wrapped in Toronto.

· 4 min read · houdini · news · sidefx · unreal · solaris

The big Houdini event this year was the Houdini 22 launch in July. Since then the news has been quieter and more practical: an updated production build, a new Houdini Engine for Unreal release to go with it, and a SideFX HIVE event in Toronto. Everything below dates from July 15 to September 23, 2026.

Houdini 22 is out (July 15)

SideFX posted the gold release, Houdini 22.0.368, on its forum on July 15, 2026. CG Channel's write-up (July 16) and 80.lv (July 15) cover the headline features:

  • Gaussian splats. A new toolset for training splats from reference photos or generating them from 3D scenes. You can deform them with standard Houdini nodes, relight them and render them in Karma. SideFX's What's New in H22 page calls the feature "production-ready".
  • KineFX and APEX. Reusable rig templates, rig inversion, a Set Driven Keys rig component, a new APEX character picker, nested clips in the Motion Mixer, and new forces and impact thresholds for ragdolls.
  • Character FX. Controls for switching LODs on rigs, new stress attributes and proper sliding constraints for soft tissue, and faster muscle simulation.
  • Copernicus. Grunge map generation, an experimental 3D texture painting workflow, a 2D ripple solver, and heightfield and ocean surface workflows. SideFX also lists GPU Pyro in Copernicus as production-ready.
  • Solaris. SideFX says Solaris "has new layout, world-building and set dressing tools".
  • UI. A theme editor with a global contrast slider, redesigned and searchable preferences, and a new color picker and ramp catalog.

For TDs, the splat toolset is the most important change. Splats can now go through the same deform, light and render steps as other geometry, so you no longer need a separate splat tool that doesn't fit your pipeline. The rig template and rig inversion work is aimed at teams that have been waiting for APEX to be ready for reusable rigs.

Production build 22.0.429 (September 1)

On September 1, 2026, SideFX announced that the Houdini 22 production build had been updated to 22.0.429. The post links to a changelog of everything since 22.0.368.

If your studio waits for the first production-build update before rolling out a new major version, this is it. Read the changelog against your own HDAs and tools before you switch builds across a show.

Houdini Engine for Unreal 4.0.1 (September 3)

SideFX's GitHub has Houdini Engine for Unreal version 4.0.1, released September 3 and built against Houdini 22.0.429 with HAPI 9.0. The release notes list source and binaries for UE 5.8 and 5.7 on Windows, and UE 5.6 on macOS (Apple silicon).

The notes list a new GetHoudiniAssetInfo() function in the public API, Cancel and Delete buttons on the Houdini Asset Component, and per-actor tags and material properties for Houdini inputs. The fixes include PDG cooking, landscape input reloading, Nanite mesh data, and PCG world input crashes.

The earlier 3.0.x line on the releases page targets Houdini 21. Moving to Houdini 22 therefore also means moving to the 4.0 plugin. Plan both upgrades together, and use the plugin that matches your exact Houdini build.

HIVE Equinox in Toronto (September 21 to 23)

SideFX held Houdini HIVE Equinox 2026 at One King West in Toronto, September 21 to 23. The listed sessions include Rodeo FX on the fire simulation for House of the Dragon season 3, authoring UE5 geometry collections from Houdini, and a SideFX talk on the VAT pipeline redesign behind Skeletal VAT. SideFX says presentations will be recorded where possible, but workshops will not. Check the HIVE page for recordings.

Sources

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