Stand-Alone PCL Projects

I have been making files within versions of my PCL git repository and adjusting the CMakeList.txt for the subdirectory to sneakily compile my custom programs. This is a safe way to avoid library linking issues, as PCL has a plethora of headers and many wonderful functions across its many files.

However, this is a guide for a cleaner way to build small stand-alone projects that use PCL libraries.

First make some directory to house your project

mkdir pcl_project

Steal your favorite example or code snippet from PCL and save it in your project root directory.
Edit the name to match the project directory name. (pcl_project.cpp)

Then create a CMakeLists.txt in your project directory that looks like the following:

cmake_minimum_required(VERSION 2.6 FATAL_ERROR)

project(pcl_project)

find_package(PCL 1.3 REQUIRED)

include_directories(${PCL_INCLUDE_DIRS})
link_directories(${PCL_LIBRARY_DIRS})
add_definitions(${PCL_DEFINITIONS})

add_executable (pcl_project pcl_project.cpp)
target_link_libraries (pcl_project ${PCL_LIBRARIES})

The tricky part is target_link_libraries which seem to take pre-defined variables. In general, this usually follows the directory hierarchy of PCL, for example ${PCL_LIBRARIES} ${PCL_VLP_VIEWER} ${PCL_IO} ${PCL_COMMON} ${PCL_VISUALIZATION} etc. See this link for PCL’s official guide on this.

Then just create a build directory, cd into there and let cmake do its magic.

$mkdir build
$cd build
$cmake ..

You should now have a Makfile which will compile your program and link against the right PCL libraries.

make

After which you smile when you see:

[100%] Building CXX object CMakeFiles/pcl_project.dir/pcl_project.cpp.o
Linking CXX executable pcl_project
[100%] Built target pcl_project

Now, if you run into issues where a certain header file cannot be found (for example, for some odd reason my compiler kept saying vlp_grabber.h does not exist while hdl_grabber.h does, even though they were in the same folder!), you need to realize that in your stand-alone project you are not actually linking to the libraries located in the pcl-trunk git repository. Instead, you are linking to header files stored in /usr/local/include/pcl-1.8/pcl/. Therefore, if you cannot link to header files or “new” header files, make sure you go back to you pcl-trunk git repo and

$make clean
$sudo make -j8 install

This will store all the headers in /usr/local/include/pcl-1.8/pcl/
By the way, the -j8 just uses all 8 logical cores to thread through the compiling faster, which, even then, takes 15 minutes.

Now you can make Stand-Alone Projects for quick and dirty testing!