I had the opportunity to produce a FLIP fluid, Lava simulation in Houdini for Splitgate 2: Inferno. This was processed into an Alembic Geometry Cache at specific framerates, custom motion vectors and applied a vertex colour driven shader in the Editor. The whole file was 48 frames long, with a footprint of 9.3MBs and a BP LOD system. Meeting our performance requirements while finely tuned for smooth playback rates and quality.
The creation process was broken down into 4 stages.
- Collision set up. Taking level geometry and Cached landscape data to produce fluid collision sources.
- Source set up. Creating emitters, setting velocities, attributes and making random connections to timelines for variation during emission.
- The Lava Simulation stage. Using the above information to produce a Cached particle simulation.
- Simulation Processing. The final stage is used to set Vertex colours, create a seamless Loop from the simulation, process the particles into an optimised piece of geometry and create LODs.
Collision creation and export.
FLIP Simulation emitter setup and attribute set.
Particle Simulation FLIP network & Result.
Final conversion, optimisation, colouring and export graph.
Examples of the simulations running from Houdini and UE5 and a Geometry Cache.