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 moving your cursor to the exact button, watching your actual Houdini window. It’s the same Houdini curriculum these lessons come from, taught live instead of read. Free to start.

Keep going

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