Houdini RBD Destruction with Bullet (beginner guide)

Fracture geometry and run rigid-body simulations using packed primitives and the Bullet solver. Here’s how to do it in Houdini on macOS, step by step — part of the free Houdini beginner curriculum.

Lesson 5 of the Houdini curriculum. Next up: Vellum — Cloth, Soft Body, and Hair.

What you’ll do

• Fracture a mesh with Voronoi Fracture SOP — the first input is the mesh, the second input is the scatter points that define fracture cells
• Refine with RBD Material Fracture for higher-level controls: glass, concrete, wood presets with built-in interior detail
• Convert pieces into packed primitives using Assemble or RBD Configure SOP — without packing, the sim treats the whole fractured mesh as one rigid body
• Use the RBD Bullet Solver SOP (the SOP-level all-in-one solver introduced in H18+) for fast iteration without diving into DOPs
• Build constraints with Connect Adjacent Pieces to create a glue or hard constraint network — wire the constraint geometry into the solver’s second input
• Set glue strength as a primitive attribute on the constraint geometry — higher = harder to break
• Add forces: Gravity, Wind, or a Pop Force node connected via the third input of the RBD Bullet Solver
• Cache the simulation with File Cache SOP — packed primitive caches are fast and small
• Unpack and add interior detail (displacement, subdivision) only after caching, never inside the sim

Do it hands-free with Skilly

Reading steps is one thing; doing them while the menus are in front of you is another. Skilly is a voice-first tutor for macOS: you ask out loud — “where’s the rbd panel?” — and it answers while pointing at the exact button, watching your actual Houdini window. It’s the same Houdini curriculum these lessons come from, taught live instead of read. 15-minute trial, no card.

Keep going

This is one stage of the full Houdini beginner curriculum. Continue with Vellum — Cloth, Soft Body, and Hair.