Houdini Main Changelogs

21.0.619

Fix framing in the APEX Animate viewport state for small controllers so that its center is correctly computed. Previously, it was slightly off center resulting in it not staying centered if you then tumbled around it.

Fri. February 6, 2026
20.0.1339

Houdini now conveys the correct resolution to render delegates through the HdRenderPassState object, instead of passing it only through the render delegate's SetRenderSettings API.

Fri. February 6, 2026
21.0.619

Fixed a bug where turning off the Enable Blendshapes display option for crowd agents did not reduce the VRAM usage if the agents had already been displayed.

Fri. February 6, 2026
21.0.619

Fix controller framing in the APEX Animate viewport state to take into account its object owner transform.

Fri. February 6, 2026
20.5.867

Houdini now conveys the correct resolution to render delegates through the HdRenderPassState object, instead of passing it only through the render delegate's SetRenderSettings API.

Fri. February 6, 2026
21.0.619

Fixed a bug where using MtlX Chiang Hair Bsdf VOP would cause shader to fail to compile.

Fri. February 6, 2026
21.0.619

Houdini now conveys the correct resolution to render delegates through the HdRenderPassState object, instead of passing it only through the render delegate's SetRenderSettings API.

Fri. February 6, 2026
20.5.867

Fixed an issue with OpenEXR texture maps that might cause too many files to be open concurrently. With large numbers of textures, it was possible for the OpenImageIO texture cache to open too many texture files, leading to system instability.

Fri. February 6, 2026
21.0.619

Don't print out missing hotkey warnings in the LOP viewer when there are custom kinds defined through the USD plugin system.

Fri. February 6, 2026
20.0.1339

When using a SOP Import to merge into the existing active layer, the source SOP geometry would be completely re-parsed up to three times instead of one. Now this translation is only performed once.

Fri. February 6, 2026
20.5.867

When using a SOP Import to merge into the existing active layer, the source SOP geometry would be completely re-parsed up to three times instead of one. Now this translation is only performed once.

Fri. February 6, 2026
21.0.619

When using a SOP Import to merge into the existing active layer, the source SOP geometry would be completely re-parsed up to three times instead of one. Now this translation is only performed once.

Fri. February 6, 2026
21.0.619

The rig::MultiBoneIK apex node now uses the pole vector to set the orientation of the first bone in the joint chain. This behavior is on by default now, since "usetwist" is set by default. It can be turned off by unsetting "usetwist".

These changes required updating KIN_IKSolverParm::myTwistAffectorFlag to false and KIN_IKSolverParm::myOffsetFlag to 0.0. These were previously ignored by the constraint solver; however, KIN_Chain is exposed in the HDK, so these flags will also need to be set by client code which uses the constrain solver via the HDK.

Fri. February 6, 2026
21.0.619

The rig::MultiBoneIK apex node now uses the pole vector to set the final orientation of the first joint in the output joint chain. This behavior can be turned off by unsetting "usetwist".

Fri. February 6, 2026
21.0.619

The Autorig Builder will now use the updated tags from metahuman.

Fri. February 6, 2026
21.0.618
  • Added support for custom primitive data via the following attributes:"unreal_num_custom_primitive_data" sets the number of custom primitive data floats to be read."unreal_custom_primitive_dataX", where X is the zero-based index of the custom float to read.
  • Details custom primitive data attributes will also be applied to the cookable component (HAC)if available. This is mostly so that they are displayed in the HAC's details.
  • Custom primitive data values are now copied to baked components/actors as well.
  • Similarily, Custom Primitive Data attributes are created for inputs (SMC, SKMC, ISMC)
Thu. February 5, 2026
21.0.618

Recipes: Fixes a bug where applying parm-data-dict to a node would reset any mutiparm instance parameters on the node, before the data was applied.

Thu. February 5, 2026
21.0.616

The Color Correct COP has changed significantly to better reflect the old COP2 Color Correct:

  • Gamma is now inverted, so higher is "brighter". To get theold behaviour, take the recipricol of your gamma values.
  • The Toggles for each type now act like bypasses. To get thethe old behaviour, set the multiply to 0,0,0 where you havepreviously used the toggle.
Tue. February 3, 2026
21.0.616

Fixed viewport slowdown when instanced lights are present but a different render delegate than HoudiniVK is used.

Tue. February 3, 2026
21.0.616

Recipes: Fixes a bug that would error during recipe creation when the vop network doesn't have a 'constant' node type.

Tue. February 3, 2026
20.5.864

Fixed a bug that could cause Houdini clones to immediately disconnect after starting up when the source hip file is large.

Tue. February 3, 2026
21.0.616

Fixed a bug that could cause Houdini clones to immediately disconnect after starting up when the source hip file is large.

Tue. February 3, 2026
21.0.615

Respect the 'Enable Background Image' parameter of the Camera object in the viewer. It was previously ignored.

Mon. February 2, 2026
20.5.862

Ramp parameters now require focus when zooming.

Mon. February 2, 2026
20.5.862

Ensure parameter choid selections are updated after a cook.

Mon. February 2, 2026