CMakeLists. Txt how to write

Recently I started to write some SLAM engineering , So do some sorting for the contents involved , So the first thing to do is to write a CMakeLists.txt. This article is about radar autopilot SLAM The engineering distance .

1 Information assignment

①cmake Version confirmation ：

cmake_minimum_required(VERSION 3.1.0)

② project name ：

project(lidar_localization)

③ Project option settings ：

SET(CMAKE_BUILD_TYPE "Release")
SET(CMAKE_CXX_FLAGS_RELEASE "$ENV{CXXFLAGS} -O3 -Wall")
add_compile_options(-std=c++11)
add_definitions(-std=c++11)

2 Looking for dependent packages

④findpackage： You can find the header file containing path of the dependent package 、 The library path 、 Library name 、 Version number, etc , For details, please refer to the link

find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
  pcl_ros
  geometry_msgs
  tf
  eigen_conversions
)

3 Path contains

⑤include_directories： Is used to add the specified directory to the compiler's header file search path , The specified directory is interpreted as the relative path of the current source path , Usually we go through include_directories Specify the path of the file we need to let the program know where the program is , See this for details link

There's a include The magic effect of
Due to the various calls and sometimes the if…else Judgment can lead to CMakeLists It's a mess , At this time, the calling contents of each package will be written as .cmake Files are placed in a fixed folder , This is CMakeLists As long as include these .cmake File can , Make the whole CMakeLists The results are clear .

include(cmake/glog.cmake)
include(cmake/PCL.cmake)
include(cmake/eigen.cmake)
include(cmake/geographic.cmake)

include_directories(include ${
    catkin_INCLUDE_DIRS})
include(cmake/global_defination.cmake)

4 Add execution file

⑥add_executable： Create an executable based on a given source file , For details, please refer to the link
Because there may be many source files added, it will lead to CMakeLists Very miscellaneous , At this point, you can use a variable to store all the required source files , Finally, give this variable to add_executable that will do .

file(GLOB_RECURSE ALL_SRCS "*.cpp")
file(GLOB_RECURSE NODE_SRCS "src/*_node.cpp")
file(GLOB_RECURSE THIRD_PARTY_SRCS "third_party/*.cpp")
list(REMOVE_ITEM ALL_SRCS ${
    NODE_SRCS})
list(REMOVE_ITEM ALL_SRCS ${
    THIRD_PARTY_SRCS})

add_executable(test_frame_node src/test_frame_node.cpp ${
    ALL_SRCS})

here ALL_SRCS That's the variable , adopt file() Create and list() Add or delete .

5 Connection Library

⑦target_link_libraries： Connect the given library file name to the executable file just created , For details, please refer to the link
alike , When there are many linked libraries, it will also lead to CMakeList Very miscellaneous , At this point, you can define a variable , Before 3 Medium include Some of the required libraries are merged into this variable , Finally to target_link_libraries that will do

set(ALL_TARGET_LIBRARIES "")

...include  Content ...

target_link_libraries(test_frame_node ${
    catkin_LIBRARIES} ${
    ALL_TARGET_LIBRARIES})

here ALL_TARGET_LIBRARIES That's the variable , stay include Written .cmake The file will pass list(APPEND ALL_TARGET_LIBRARIES ${XX_LIBRARIES}) Merge the required libraries .

Variables and options

CMAKE_BUILD_TYPE： Specify the compilation type , The common one is Debug and Release
CMAKE_CXX_FLAGS_RELEASE： compile Release The compilation options used in version

add_compile_options()： Add compile options , Same as SET(CMAKE_CXX_FLAGS …) + SET(CMAKE_C_FLAGS) The effect is the same , example ：add_compile_options(-std=c++11) to c++ and c Compile with c++11 Support options , link
add_definitions()： Used to add flag bits , link

Final CMakeLists.txt

cmake_minimum_required(VERSION 2.8.3)
project(lidar_localization)

SET(CMAKE_BUILD_TYPE "Release")
SET(CMAKE_CXX_FLAGS_RELEASE "$ENV{CXXFLAGS} -O3 -Wall")
add_compile_options(-std=c++11)
add_definitions(-std=c++11)

find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
  pcl_ros
  geometry_msgs
  tf
  eigen_conversions
)
set(ALL_TARGET_LIBRARIES "")

include(cmake/glog.cmake)
include(cmake/PCL.cmake)
include(cmake/eigen.cmake)
include(cmake/geographic.cmake)

include_directories(include ${
    catkin_INCLUDE_DIRS})
include(cmake/global_defination.cmake)
catkin_package()

file(GLOB_RECURSE ALL_SRCS "*.cpp")
file(GLOB_RECURSE NODE_SRCS "src/*_node.cpp")
file(GLOB_RECURSE THIRD_PARTY_SRCS "third_party/*.cpp")
list(REMOVE_ITEM ALL_SRCS ${
    NODE_SRCS})
list(REMOVE_ITEM ALL_SRCS ${
    THIRD_PARTY_SRCS})

add_executable(test_frame_node src/test_frame_node.cpp ${
    ALL_SRCS})
target_link_libraries(test_frame_node ${
    catkin_LIBRARIES} ${
    ALL_TARGET_LIBRARIES})