• Vellum brush tools for interactive brushing of Vellum cloth, Vellum hair, and Vellum softbodies in the viewport.

  • Ability to operate quasi-statically with velocity damping in the Vellum brush state.

  • Secondary bend constraint pass option for faster cloth solving and more stable sliding. This is useful when working with material like silk or cotton, as they have very low bend resistance and wrinkle easily. Solving the bend constraints as a secondary pass will give you strong performance gains.

  • Attach constraints with Use Closest Location on Primitive enabled will now be smoothed along with other distance constraints when performing Smoothing Iterations in the Vellum Solver.

  • The Vellum Solver has a new Sliding Method called Traverse Triangles (Optimized) that has the same improved handling of concavities as Traverse Polygons, but can be many times faster for high-resolution geometry.

  • Per-point pressure scale for interesting inflation effects.

  • Fast pressure constraints and better occupancy during constraint solve on GPU.

  • New Vellum Constraint Property SOP to easily modify common properties of Vellum constraints.

  • Constraint tags that store a string in the constraint_tag primitive attribute for all constraints created by that node.

  • The Vellum Constraints SOP and DOP now have an optional Min Stiffness parameter that controls the minimum stiffness value used when calculating the Stiffness Dropoff.

  • Interactive GPU-accelerated minimal solver with nanoVDB support for use with Vellum brushes.

  • Downloadable fabric setups with physical properties and shaders from the SideFX Content Library.


Fast pressure and shape match constraints require the latest driver for NVIDIA Ampere series cards. This is version 456.38 on Windows and version 450.80.02 on Linux.

If you don’t update your driver, you can alternatively set the following environment variable to disable this feature: HOUDINI_OCL_FEATURE_DISABLE=CL_DEVICE_DEVICE_ENQUEUE_SUPPORT. For more information, see environment variables.

What’s new in Houdini 18.5