Cross-platform GPU multiphysics simulation

/!\ This library is still under heavy development and is still missing many features.

The goal of nexus is to essentially be "rapier on the GPU". It aims to be a cross-platform GPU-accelerated multiphysics engine, running compute shaders via WebGPU. Shaders are written in Rust using Rust-GPU and compiled to SPIR-V.

Physics modules

Nexus is organized into independent physics modules, each available in 2D and 3D:

• nexus_rbd - Rigid-body dynamics: colliders (boxes, balls, convex shapes, trimeshes, heightfields), joints (ball, fixed, prismatic, revolute), contact resolution.

Prerequisites

Install cargo gpu

Nexus uses cargo gpu to compile its Rust-GPU shaders to SPIR-V during the build. You must install it before building, otherwise the shader compilation step will fail:

cargo install cargo-gpu --version 0.10.0-alpha.1
cargo gpu install # Install the toolchain needed by cargo-gpu

For building running on the browser:

rustup target add wasm32-unknown-unknown
cargo install wasm-server-runner

WebGpu might not be enabled on your browser:

• It is often already enabled by default on Windows and Macos major browsers.
• On Firefox, go to about:config then set dom.webgpu.enabled to true.
• On chromium, go to chrome://flags then set Unsafe WebGPU Support to Enabled. Keep in mind that, on Ubuntu, we observed WebGPU performances to be significantly worse on chromium compared to Firefox.
• Safari is currently not supported by Nexus.

Running the examples

The example binaries launch a viewer window with all available demos. Use the --release flag for good performance, as debug builds of GPU physics code will be very slow.

# Run natively
cargo run --release --bin all_examples3
cargo run --release --bin all_examples2
# Run on the browser
cargo run --release --bin all_examples3 --target wasm32-unknown-unknown
cargo run --release --bin all_examples2 --target wasm32-unknown-unknown

Python bindings

The 3D engine and viewer are also available from Python as the nexus3d module (PyO3 + maturin), mirroring the Rust API closely. See crates/nexus_python3d/README.md for building instructions and a full set of example scripts (rigid bodies, joints, and URDF/MJCF robots).

License

MIT OR Apache-2.0