BehaviorTree.CPP

Project notes

Pick a build route before adapting the tutorial

The pinned README labels the project 4.9 and requires a C++17 compiler. It lists ROS2 colcon/ament, Conan and straight CMake routes, with pixi also documented. Conan builds require CMake 3.23 or newer. These routes manage dependencies differently; package-manager versions installed today need not equal the inspected source revision. No build was performed. [1]

For the documented Conan route, run from the repository root: conan install . -s build_type=Release --build=missing, then cmake --preset conan-release and cmake --build --preset conan-release. The straight-CMake alternative expects dependencies such as ZeroMQ and SQLite to be installed separately, then uses cmake -S . -B build_release and cmake --build build_release --parallel. Choose one route rather than combining their assumptions. [1]

The library bundles nlohmann/json. The README says that selecting a system copy with -DUSE_VENDORED_JSON=OFF requires version 3.10 or later, and all code linking the public API must use the same version. That compatibility boundary matters when integrating into an existing application. [1]

Read the first tree as a callback example

The inspected examples/t01_build_your_first_tree.cpp registers nodes through BehaviorTreeFactory, creates a tree from XML text and calls tickWhileRunning(). Its sequence names battery, open-gripper, approach-object and close-gripper nodes. Those names describe tutorial callbacks, not observed device actions. [3]

By default, the source loads ../sample_nodes/bin/libdummy_nodes_dyn.so. A compile-time MANUAL_STATIC_LINKING branch instead registers dummy nodes and callbacks individually. The plugin must actually exist at the expected path for that default tutorial route; the source's expected-output comment is not a successful run from this review. Inspect registration names against XML node names before adapting the example. [3]

For a robot integration, replace tutorial callbacks with actual application actions and define their success, failure, running and interruption behavior. A callback returning success cannot establish physical execution or recovery by itself. Neither the sample's dummy plugin nor a tree tick verifies external IPC, motor feedback or persistence. [1] [3]

The repository is MIT licensed; bundled dependencies and separately linked tools retain their own terms. Groot2 is linked as an optional graphical editor, not established here as part of the library's license grant. No dependency installation, compilation, plugin load, tutorial execution, asynchronous cancellation or robot action was tested. [1] [2]