ROS2 Humble

下载ros2源码：

git clone https://github.com/ros2/ros2.git -b humble
cd ros2
mkdir -p src
vcs import --recursive src < ros2.repos

编译：

colcon build --event-handlers console_cohesion+ --cmake-args -DBUILD_TESTING=ON --no-warn-unused-cli

单独编译某个模块：

colcon build --event-handlers console_cohesion+ --packages-select rviz_ogre_vendor

编译过程中遇到一些依赖库下载慢导致编译时间很长或失败，可以手动下载依赖库，参考下面的参考文章，修改对应的CMakeLists.txt，如rviz_ogre_vendor这个依赖库：
修改src/ros2/rviz/rviz_ogre_vendor/CMakeLists.txt：
修改对应的URL和URL_MD5

ExternalProject_Add(ogre-v1.12.1
    #URL https://github.com/OGRECave/ogre/archive/v1.12.1.zip
    #URL_MD5 cdbea4006d223c173e0a93864111b936
    URL /home/ubuntu/ros2/build/rviz_ogre_vendor/ogre-v1.12.1-prefix/src/ogre-1.12.1.zip
    URL_MD5 cdbea4006d223c173e0a93864111b936
    TIMEOUT 1200
    LOG_CONFIGURE ${should_log}
    LOG_BUILD ${should_log}
    CMAKE_ARGS
      -DOGRE_STATIC:BOOL=OFF
      -DOGRE_DEPENDENCIES_DIR=${CMAKE_CURRENT_BINARY_DIR}/ogredeps
      -DOGRE_INSTALL_PDB:BOOL=OFF
      -DOGRE_BUILD_DEPENDENCIES:BOOL=OFF
      -DOGRE_BUILD_TESTS:BOOL=OFF
      -DOGRE_BUILD_SAMPLES:BOOL=FALSE
      -DOGRE_INSTALL_SAMPLES:BOOL=FALSE
      -DOGRE_INSTALL_SAMPLES_SOURCE:BOOL=FALSE
      -DOGRE_CONFIG_THREADS:STRING=0
      -DOGRE_RESOURCEMANAGER_STRICT:STRING=2
      -DCMAKE_SKIP_INSTALL_RPATH:BOOL=ON
      -DCMAKE_INSTALL_PREFIX=${CMAKE_CURRENT_BINARY_DIR}/ogre_install
      -DOGRE_BUILD_LIBS_AS_FRAMEWORKS:BOOL=OFF
      -DOGRE_BUILD_COMPONENT_PYTHON:BOOL=FALSE
      -DOGRE_BUILD_COMPONENT_JAVA:BOOL=FALSE
      -DOGRE_BUILD_COMPONENT_CSHARP:BOOL=FALSE
      -DOGRE_BUILD_COMPONENT_BITES:BOOL=FALSE
      ${extra_cmake_args}
      -Wno-dev
    PATCH_COMMAND
      ${Patch_EXECUTABLE} -p1 -N < ${CMAKE_CURRENT_SOURCE_DIR}/pragma-patch.diff &&
      ${Patch_EXECUTABLE} -p1 -N < ${CMAKE_CURRENT_SOURCE_DIR}/fix-arm64.diff &&
      ${Patch_EXECUTABLE} -p1 -N < ${CMAKE_CURRENT_SOURCE_DIR}/relocatable.patch
    COMMAND
      ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/FindFreetype.cmake ${CMAKE_CURRENT_BINARY_DIR}/ogre-v1.12.1-prefix/src/ogre-v1.12.1/CMake/Packages/FindFreetype.cmake
  )

测试：
打开一个终端，运行C++编写的talker：

ros2 run demo_nodes_cpp talker

打开另外一个终端，运行Python编写的listener：

ros2 run demo_nodes_py listener

参考文章

Ubuntu 20.04下源码编译安装ROS 2 Foxy Fitzroy