/BehaviorTree.CPP

Behavior Trees Library in C++. Batteries included.

Primary LanguageC++MIT LicenseMIT

License MIT Version cmake ros1 ros2 LGTM Grade Discourse topics

BehaviorTree.CPP 4.0

This C++ 17 library provides a framework to create BehaviorTrees. It was designed to be flexible, easy to use, reactive and fast.

Even if our main use-case is robotics, you can use this library to build AI for games, or to replace Finite State Machines.

There are few features that make BehaviorTree.CPP unique, when compared to other implementations:

  • It makes asynchronous Actions, i.e. non-blocking, a first-class citizen.

  • You can build reactive behaviors that execute multiple Actions concurrently.

  • Trees are defined using a Domain Specific scripting language (based on XML), and can be loaded at run-time; in other words, even if written in C++, the morphology of the Trees is not hard-coded.

  • You can statically link your custom TreeNodes or convert them into plugins and load them at run-time.

  • It provides a type-safe and flexible mechanism to do Dataflow between Nodes of the Tree.

  • It includes a logging/profiling infrastructure that allows the user to visualize, record, replay and analyze state transitions.

Documentation and Community

You can learn about the main concepts, the API and the tutorials here: https://www.behaviortree.dev/

If the documentation doesn't answer your questions and/or you want to connect with the other BT.CPP users, visit https://discourse.behaviortree.dev/

Previous version

Version 3.8 of the software can be found in the branch v3.8.

That branch might receive bug fixes, but the new features will be implemented only in the master branch.

Commercial support

Are you using BT.CPP in your commercial product and you need technical support / consulting? You can contact the main author dfaconti@aurynrobotics.com to discuss your use case and needs.

Design principles

The main goal of this project is to create a Behavior Tree implementation that uses the principles of Model Driven Development to separate the role of the Component Developer from the Behavior Designer.

In practice, this means that:

  • Custom TreeNodes must be reusable building blocks. You should be able to implement them once and reuse them to build many behaviors.

  • To build a Behavior Tree out of TreeNodes, the Behavior Designer must not need to read nor to modify the C++ source code..

  • Complex Behaviours must be composable using Subtrees.

GUI Editor

Editing a BehaviorTree is as simple as editing a XML file in your favourite text editor.

If you are looking for a more fancy graphical user interface (and I know you do) check Groot out.

Groot screenshot

How to compile (Ubuntu)

Please note that Ubuntu 18.04 is not supported anymore in version 4.X. Ubuntu 20.04 or later is required.

First, install the following dependencies (optional, but recommended):

 sudo apt-get install libzmq3-dev libboost-dev

To compile and install the library, from the BehaviorTree.CPP folder, execute:

 mkdir build; cd build
 cmake ..
 make
 sudo make install

If you want to use BT.CPP in your application a typical CMakeLists.txt file will look like this:

cmake_minimum_required(VERSION 3.10.2)
project(hello_BT)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
find_package(behaviortree_cpp)

add_executable(${PROJECT_NAME} "hello_BT.cpp")
target_link_libraries(${PROJECT_NAME} BT::behaviortree_cpp)

License

The MIT License (MIT)

Copyright (c) 2014-2018 Michele Colledanchise

Copyright (c) 2018-2019 Davide Faconti, Eurecat

Copyright (c) 2019-2022 Davide Faconti

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.