IPC Contact¶

Overview¶

NovaPhy integrates libuipc to provide GPU-accelerated Incremental Potential Contact (IPC) with mathematically guaranteed penetration-free contact.

Optional Feature

IPC requires CUDA >= 12.4 and must be enabled at build time with NOVAPHY_WITH_IPC=ON.

How It Works¶

The IPC pipeline:

Shape Conversion — NovaPhy shapes are converted to tetrahedral meshes
GPU Newton Solver — libuipc solves the barrier-based contact problem on GPU
Barrier Contact — Log-barrier potential guarantees no interpenetration

Build with IPC¶

# Initialize libuipc submodule
git submodule update --init --recursive

# Build with IPC
CMAKE_ARGS="--preset=ipc" pip install -e .

Usage¶

import novaphy

if novaphy.has_ipc():
    builder = novaphy.ModelBuilder()
    # ... add bodies and shapes ...

    config = novaphy.IPCConfig()
    config.dt = 1.0 / 60.0

    ipc_world = novaphy.IPCWorld(builder.build(), config)
    for _ in range(100):
        ipc_world.step()

When to Use IPC¶

Scenario	Recommended Solver
Real-time simulation	SolverSemiImplicit / SolverFeatherstone
Guaranteed no-penetration	IPCWorld
Deformable objects (future)	IPCWorld
Large-scale contact	IPCWorld

Demo¶

python demos/demo_ipc_stack.py

Requirements¶

CUDA >= 12.4
Compatible C++ compiler (see Build Documentation)
libuipc git submodule initialized