Bevy XPBD is a physics engine based on Extended Position Based Dynamics (XPBD) for the Bevy game engine.

This is an experimental work-in-progress that I am working on because I'm interested in learning about physics engines. You probably shouldn't use this for anything serious.

Currently this physics engine supports Bevy 0.9.1, and I will try to keep up with major releases.

Note: No crate is available on Cargo yet. I will publish this as a crate when I have fixed the biggest issues, reached respectable performance and added enough documentation.

• 2D and 3D support
• Dynamic and static rigid bodies
• Position and rotation integration and solving
• Linear and angular velocity integration and solving
• Collision detection via parry
• Basic joints
  • Revolute joint (or hinge joint), optional angle limits
  • Spherical joint, optional swing and twist angle limits
  • Prismatic joint, one free translational axis with optional limits
  • Fixed joint
• Joint damping
• Gravity
• External forces
• Restitution
• Friction
• Substepping

• Linear and angular velocity damping
• Locking translational and rotational axes without joints
• Collision groups
• Publicly accessable contact data
• Performance optimization (sleeping, multithreading...)
• Maybe basic soft bodies
• Maybe (unlikely) fluid simulation

• Documentation
• More examples
• Publish crate

• Johan Helsing's amazing but incomplete tutorial; I probably wouldn't have started without it
• The original papers
  • XPBD: Position-Based Simulation of Compliant Constrained Dynamics
  • Detailed Rigid Body Simulation with Extended Position Based Dynamics (I have used this one way more)

Bevy XPBD is free and open source. All code in this repository is dual-licensed under either:

• MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)
• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)