This repository contains test projects, examples, and a test package for Unity's 2D physics, spanning two API generations:
- PhysicsCore2D — examples for the newer 2D physics core API (
Unity.U2D.Physics), located at the repository root:- Sandbox Project — interactive playground scenes
- Primer Project — focused single-concept examples
- Snippets Project — minimal API usage demos
- OldPhysics2D — examples that use the older "Physics2D" component API.
Packages/com.unity.2d.physics.extras is a shared local package referenced by the PhysicsCore2D projects.
.claude/ contains skills you can copy into your own .claude folder to better work with PhysicsCore2D.
Acknowledgement and thanks to Erin Catto (the creator of Box2D v3), upon which significant portions of the "Sandbox" project are based.
https://github.com/erincatto/box2d
Each branch represents a specific version of Unity. As features are added in a public release, those features should be represented in that branch and future Unity version branches i.e. branch names such as "2022", "6000.3" (etc) exist.
masterrepresents the current latest release of Unity, updated only when new final releases have been public for a while.unsupported/xxxrepresents versions that are currently in alpha/beta release state.
Older Unity version branches are not kept as live branches. They are archived as annotated tags named archive/<version> (for example archive/2019, archive/6000.1). A tag preserves the exact final state of that version permanently while keeping the branch list focused on supported versions.
To archive a branch, tag its tip, push the tag, then delete the branch:
git tag -a archive/2019 origin/2019 -m "Archive 2019 branch"
git push origin archive/2019
git push origin --delete 2019To restore an archived version into a working branch:
git branch 2019 archive/2019Twitter: https://twitter.com/melvmay
Unity Discussions: https://forum.unity.com/members/melvmay.287484/