Houdini - Derelict Impact

Following my dive into Houdini’s TerrainFX suite I dove right into working with Rigidbody simulations. It was also a chance for me to learn more about Houdini’s built in scripting language Vex. Though that dive first took its real start in the next project!

This project is my first dive into working with large scale rigid-body simulations. My inspiration for it came after watching an episode of The Expanse where a spaceship explodes, creating a massive debris field. I looked around on google for spaceships the reminded me of the designs from The Expanse. Sasa ke, inyalowda?


Finally I settled on creating a modular cargo ship. I built it in Blender, using a instancing heavy workflow to reduce the amount of actual geometry I had to make. This also enabled me to dynamically make the ship longer or shorter with a simple slider.


Next I exported the ship in parts, using many OBJ files. Each OBJ contained a different section of the ship, which enabled me to fine-tune how each part fractured in the final simulation. For every section I have a specifically tailored fracture that I fine tuned for the effect I wanted.


The next, and almost final step in setting up the simulation was creating the DOP network. In this i had even more controls of the fracture, as I chose to integrate Houdini's procedural shatter. It proved a bit more difficult to use than I had expected. The procedural shatter was very memory heavy. As such I opted in for only using it on the larger chunky bits. To further limit it I also set it to only do a single additional fracture.

Originally I had not planned on having the ship crash into an asteroid, but rather have some kind of major malfunction. I had already setup explosive forces using metaballs. But the system I had for removing the glue within the force sphere of influence did not work like i wanted. This lead to the explosions not actually making things blow up, but instead pushing them away. Because of this i decided to crash the ship into an asteroid instead. I also thought it would be fun to see one massive object shatter into another. The metaball forces are however still in use, as I used them to propel the command module away from the asteroid. This was to try and give the impression of the pilots trying to avoid imminent doom as the ship shattered around them.