Here are quick instructions on how to generate and access the API documentation of BehaviourTree.CPP v3.8.7 which is the last V3 released in ROS 1 Noetic.

Why?

While there is plenty online documentation available for BehaviourTree.CPP V4, documentation for V3 has since been deprecated, along ROS 1 Noetic Ninjemys which reached End-Of-Life (EOL) in May 2025.

Documentation on the official BehaviourTree.CPP website is now focused on V4 and does not provide necessary exact API documentations for V3.

Even though each release of BehaviourTree.CPP is accompanied with a Doxyfile that allows for automatic API documentation generation. It is not as straightforward as to directly use it given that the sources and outputs defined in its root Doxyfile are hardcoded to non-existent directories.

Therefore, modifications have been made and instructions are provided to allow for an easier access to V3 API documentations.

Steps

1. Download modified v3.8.7 BehaviourTree.CPP:

 git clone https://github.com/cardboardcode/BehaviorTree.CPP.git --branch v3/docs_fix --depth 1 --single-branch && cd BehaviorTree.CPP

2. Build the API Doxygen Documentations:

 doxygen Doxyfile

3. View the API Doxygen Documentations

 xdg-open ./output_doc/html/index.html >/dev/null 2>&1 &

References