Build Status

Box2D

Box2D is a 2D physics engine for games.

Contributing

Please do not submit pull requests with new features or core library changes. Instead, please file an issue first for discussion. For bugs, I prefer detailed bug reports over pull requests.

Features

Collision

Continuous collision detection
Contact callbacks: begin, end, pre-solve, post-solve
Convex polygons and circles
Multiple shapes per body
One-shot contact manifolds
Dynamic tree broadphase
Efficient pair management
Fast broadphase AABB queries
Collision groups and categories

Physics

Continuous physics with time of impact solver
Persistent body-joint-contact graph
Island solution and sleep management
Contact, friction, and restitution
Stable stacking with a linear-time solver
Revolute, prismatic, distance, pulley, gear, mouse joint, and other joint types
Joint limits, motors, and friction
Momentum decoupled position correction
Fairly accurate reaction forces/impulses

System

Small block and stack allocators
Centralized tuning parameters
Highly portable C++ with no use of STL containers

Testbed

OpenGL with GLFW
Graphical user interface with imgui
Extensible test framework
Support for loading world dumps

Building

Install CMake
Ensure CMake is in the user PATH
Visual Studio: run build.bat from the command prompt
Otherwise: run build.sh from a bash shell
Results are in the build sub-folder
On Windows you can open box2d.sln

Building Box2D - Using vcpkg

You can download and install Box2D using the vcpkg dependency manager:

git clone https://github.com/Microsoft/vcpkg.git
cd vcpkg
./bootstrap-vcpkg.sh
./vcpkg integrate install
./vcpkg install box2d

The Box2D port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.

Note: vcpkg support is not provided by the Box2D project

Building for Xcode

Install CMake
Add Cmake to the path in .zprofile (the default Terminal shell is zsh)
- export PATH="/Applications/CMake.app/Contents/bin:$PATH"
mkdir build
cd build
cmake -G Xcode ..
open box2d.xcodeproj
Select the testbed scheme
Edit the scheme to set a custom working directory, make this be in box2d/testbed
You can now build and run the testbed

Installing using CMake

You can build and install the library and docs using this command sequence (requires Doxygen):

mkdir build
cd build
cmake -DBOX2D_BUILD_DOCS=ON ..
cmake --build .
cmake --build . --target INSTALL

On Windows this tries to install in Program Files and thus requires admin privileges. Alternatively you can target another directory using something like this:

mkdir build
cd build
cmake -DBOX2D_BUILD_DOCS=ON -DCMAKE_INSTALL_PREFIX="C:/packages" ..
cmake --build .
cmake --build . --target INSTALL

Box2d