Many of you may have already seen an impressive real-time destruction and fluid simulation demo from GDC 2013.

Update: Position Based Fluids explained

Update #2: Introducing NVIDIA FLEX: unified GPU PhysX solver

We won’t talk about fracturing technology today, instead, let’s focus on the new fluid simulation algorithm, presented in the demo – it is known as Position Based Fluids.

Position Based Fluids is a way of simulating liquids using Position Based Dynamics (PBD), the same framework that is utilized for cloth and deformables simulation in PhysX SDK.

Because PBD uses an iterative solver, it can maintain incompressibility more efficiently than traditional SPH fluid solvers. It also has an artificial pressure term which improves particle distribution and creates nice surface tension-like effects (note the filaments in the splashes). Finally, vorticity confinement is used to allow the user to inject energy back to the fluid.

More details on this a new technique will be available later on, in a SIGGRAPH 2013 paper “Position-Based Fluids” by Miles Macklin and Matthias Mueller-Fischer, and we also expect it to be included in future versions of PhysX SDK or APEX modules.