box3d

# Box3D

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![Box3D Logo](https://box2d.org/images/logo.svg)

Box3D is a 3D physics engine for games.

[![Introducing Box3D](https://img.youtube.com/vi/jr_Fzl2XwKU/maxresdefault.jpg)](https://www.youtube.com/watch?v=jr_Fzl2XwKU)

## Features

### Collision

- Continuous collision detection
- Contact events
- Convex hulls, capsules, spheres, triangle meshes, and height fields
- Multiple shapes per body
- Collision filtering
- Ray casts, shape casts, and overlap queries
- Sensor system
- Character mover

### Physics

- Robust _Soft Step_ rigid body solver
- Continuous physics for fast translations and rotations
- Island based sleep
- Revolute, prismatic, distance, motor, weld, and wheel joints
- Joint limits, motors, springs, and friction
- Joint and contact forces
- Body movement events and sleep notification

### System

- Data-oriented design
- Written in portable C17
- Extensive multithreading and SIMD
- Optimized for large piles of bodies
- Cross platform determinism
- Recording and replay

### Samples

- Uses sokol to run with D3D11 on Windows, Metal on macOS, and OpenGL 4.5 on Linux.
- Graphical user interface with imgui.
- Many samples to demonstrate features and performance.

## Building all platforms

- Install [CMake](https://cmake.org/)
- Install [git](https://git-scm.com/)
- Ensure these run from the command line

## Building with CMake presets (recommended)

This uses the presets in `CMakePresets.json`.

- Windows: `cmake --preset windows` then `cmake --build --preset windows-release`
- Linux: `cmake --preset linux-release` then `cmake --build --preset linux-release`
- macOS: `cmake --preset macos` then `cmake --build --preset macos-release`
- Windows MinGW: `cmake --preset mingw-release` then `cmake --build --preset mingw-release`

Run the samples app (must be in the Box3D directory).

- Windows: `.\build\bin\Release\samples.exe`
- Linux: `./build/bin/samples`
- macOS: `./build/bin/Release/samples`

## Building for Visual Studio

- Install [Visual Studio](https://visualstudio.microsoft.com/)
- Run `build_vs2026.bat`
- Open and build `build/box3d.slnx`

## Building for Linux

- Run `build.sh` from a bash shell
- Results are in the build sub-folder

## Building for Xcode

- mkdir build
- cd build
- cmake -G Xcode ..
- Open `box3d.xcodeproj`
- Select the samples scheme
- Build and run the samples

## Building for Web

- [Emscripten SDK](https://emscripten.org/docs/getting_started/downloads.html)
- `emcmake cmake -B build -DBOX3D_SAMPLES=OFF`
- `cmake --build build`

Box3D uses SSE2 with WebAssembly. Define `BOX3D_DISABLE_SIMD` to disable SSE2.

## Building and installing

- mkdir build
- cd build
- cmake ..
- cmake --build . --config Release
- cmake --install . (might need sudo)

## Using Bo