PCL安装过程

Ubuntu18.04安装PCL（详细教程）

1.1 安装依赖

sudo apt-get update  
sudo apt-get install git build-essential linux-libc-dev
sudo apt-get install cmake cmake-gui
sudo apt-get install libusb-1.0-0-dev libusb-dev libudev-dev
sudo apt-get install mpi-default-dev openmpi-bin openmpi-common 
sudo apt-get install libflann1.9 libflann-dev
sudo apt-get install libeigen3-dev 这个需要自己下载正确版本安装
sudo apt-get install libboost-all-dev
sudo apt-get install libvtk7.1-qt    （以下三个换成libvtk6，我的6可以7不能使）
sudo apt-get install libvtk7.1 
sudo apt-get install libvtk7-qt-dev（按照错误提示一步一步安装所需要的东西） 
sudo apt-get install libqhull* libgtest-dev
sudo apt-get install freeglut3-dev pkg-config
sudo apt-get install libxmu-dev libxi-dev
sudo apt-get install mono-complete
sudo apt-get install openjdk-8-jdk openjdk-8-jre

1.2 下载编译

git clone https://github.com/PointCloudLibrary/pcl.git 
cd pcl 
mkdir release 
cd release
cmake -DCMAKE_BUILD_TYPE=None -DCMAKE_INSTALL_PREFIX=/usr \ -DBUILD_GPU=ON-DBUILD_apps=ON -DBUILD_examples=ON \ -DCMAKE_INSTALL_PREFIX=/usr .. 
make  
sudo make install

cmake …出现错误1：

The imported target "vtkRenderingPythonTkWidgets" references the file
   "/usr/lib/x86_64-linux-gnu/libvtkRenderingPythonTkWidgets.so"
but this file does not exist.  Possible reasons include:
* The file was deleted, renamed, or moved to another location.
* An install or uninstall procedure did not complete successfully.
* The installation package was faulty and contained
   "/usr/lib/cmake/vtk-6.2/VTKTargets.cmake"
but not all the files it references.

-- The imported target "vtk" references the file
   "/usr/bin/vtk"
but this file does not exist.  Possible reasons include:
* The file was deleted, renamed, or moved to another location.
* An install or uninstall procedure did not complete successfully.
* The installation package was faulty and contained
   "/usr/lib/cmake/vtk-6.2/VTKTargets.cmake"
but not all the files it references

千万不可sudo apt install python-vtk解决，会导致ROS的依赖丢失，ROS不可用。
建议使用sudo ln -s /usr/bin/vtk6 /usr/bin/vtk

这里需要注意一点，vtk有安装7.0/7.1，也有6.2版本。我这里试了sudo ln -s /usr/bin/vtk7 /usr/bin/vtk不行，建立软链接之后依然出现问题，必须使用vtk6才行。

cmake …出现错误2：

CMake Error at /usr/lib/cmake/vtk-7.1/vtkModuleAPI.cmake:120 (message):
  Requested modules not available:
 
    vtkRenderingOpenGL
Call Stack (most recent call first):
  /usr/lib/cmake/vtk-7.1/VTKConfig.cmake:89 (vtk_module_config)
  cmake/OpenCVDetectVTK.cmake:6 (find_package)
  CMakeLists.txt:597 (include)

在opencv/cmake目录下，将OpencvDetectVTK.cmake文件中前几行的对应模块名后面加个2

/home/lyp/third_part/opencv/cmake/OpencvDetectVTK.cmake

将vtkRenderingOpenGL修改成vtkRenderingOpenGL2

# VTK 6.x components
find_package(VTK QUIET COMPONENTS vtkRenderingOpenGL2 vtkInteractionStyle vtkRenderingLOD vtkIOPLY vtkFiltersTexture vtkRenderingFreeType vtkIOExport NO_MODULE)

ROS系统被删除问题3：

万一ROS丢失了怎样修补？

参考链接： https://blog.csdn.net/haiyinshushe/article/details/84256137

sudo apt install libpcl-dev
sudo apt install libvtk6-java
sudo apt install libvtk6-jni
sudo apt install libvtk6-dev
sudo apt install libvtk6-qt-dev
sudo apt install ros-melodic-pcl-conversions
sudo apt install ros-melodic-perception-pcl
sudo apt-get install ros-melodic-desktop-full

运行roscore，出现错误：

Resource not found: roslaunch
ROS path [0]=/opt/ros/noetic/share/ros
ROS path [1]=/opt/ros/noetic/share
The traceback for the exception was written to the log file

我的关机重启竟然好了，如果不行那就再解决吧。

---

至此，PCL能用了：
test_pcl.cpp

#include <iostream>
#include <pcl/common/common_headers.h>
#include <pcl/io/pcd_io.h>
#include <pcl/visualization/pcl_visualizer.h>
#include <pcl/visualization/cloud_viewer.h>
#include <pcl/console/parse.h>

int main(int argc, char **argv) {
  std::cout << "Test PCL !" << std::endl;
  pcl::PointCloud<pcl::PointXYZRGB>::Ptr point_cloud_ptr (new pcl::PointCloud<pcl::PointXYZRGB>);
  uint8_t r(255), g(15), b(15);
  for (float z(-1.0); z <= 1.0; z += 0.05) {
    for (float angle(0.0); angle <= 360.0; angle += 5.0) {
      pcl::PointXYZRGB point;
      point.x = 0.5 * cosf (pcl::deg2rad(angle));
      point.y = sinf (pcl::deg2rad(angle));
      point.z = z;
      uint32_t rgb = (static_cast<uint32_t>(r) << 16 | static_cast<uint32_t>(g) << 8 | static_cast<uint32_t>(b));
      point.rgb = *reinterpret_cast<float*>(&rgb);
      point_cloud_ptr->points.push_back (point);
    }
    if (z < 0.0) {
      r -= 12;
      g += 12;
    }
    else {
      g -= 12;
      b += 12;
    }
  }

  point_cloud_ptr->width = (int) point_cloud_ptr->points.size ();
  point_cloud_ptr->height = 1;

  pcl::visualization::CloudViewer viewer ("test");
  viewer.showCloud(point_cloud_ptr);
  while (!viewer.wasStopped()){ };
  return 0;
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.6)
project(test_pcl)

find_package(PCL 1.8 REQUIRED)

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

add_executable(test_pcl test_pcl.cpp)

target_link_libraries (test_pcl ${PCL_LIBRARIES})

install(TARGETS test_pcl RUNTIME DESTINATION bin)

然后

mkdir build
cd build
cmake ..
make
./test_pcl

测试效果（说明PCL安装成功）：