[Study notes] To programing RGBD-SLAM together from Gaoxiang

Solve CMake Error in CMakeLists.txt (FIND_PAKAGE):

CMake Error at src/CMakeLists.txt:5 (FIND_PACKAGE):
  By not providing "FindPCL.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "PCL", but
  CMake did not find one.

  Could not find a package configuration file provided by "PCL" with any of
  the following names:

    PCLConfig.cmake
    pcl-config.cmake

  Add the installation prefix of "PCL" to CMAKE_PREFIX_PATH or set "PCL_DIR"
  to a directory containing one of the above files.  If "PCL" provides a
  separate development package or SDK, be sure it has been installed.

-- Configuring incomplete, errors occurred!

• To help cmake find PCLConfig.cmake adding this line if you have installed ROS Kinetic:

set(PCL_DIR "/usr/lib/x86_64-linux-gnu/cmake/pcl/PCLConfig.cmake")

before find_package(PCL 1.3 REQUIRED COMPONENTS common io)

Or run loacate PCLConfig.cmake.

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Solve Complile Erorr

.../rgbd-slam-tutorial-gx-master/part IV/src/slamBase.cpp: In function ‘void computeKeyPointsAndDesp(FRAME&, std::__cxx11::string, std::__cxx11::string)’:
.../rgbd-slam-tutorial-gx-master/part IV/src/slamBase.cpp:63:17: error: ‘create’ is not a member of ‘cv::FeatureDetector {aka cv::Feature2D}’
     _detector = cv::FeatureDetector::create( detector.c_str() );
                 ^
.../rgbd-slam-tutorial-gx-master/part IV/src/slamBase.cpp:64:19: error: ‘create’ is not a member of ‘cv::DescriptorExtractor {aka cv::Feature2D}’
     _descriptor = cv::DescriptorExtractor::create( descriptor.c_str() );

• See How to solve multi-version conflict of OpenCV or PCL on ROS kinetic?

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Bug fixed: When adding another visualization of pcl::visualization::CloudViewer.

[xcb] Unknown request in queue while dequeuing
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
visualOdometry: ../../src/xcb_io.c:179: dequeue_pending_request: Assertion `!xcb_xlib_unknown_req_in_deq' failed.
Aborted (core dumped)

We can see Note in The CloudViewer of pcl documents

The CloudViewer class is NOT meant to be used in multi-threaded applications! Please check the documentation on :pcl:PCLVisualizer<pcl::visualization::PCLVisualizer> or read the PCLVisualizer tutorial for thread safe visualization.

The Viewer window does not be shutdown in visualOdometry.cpp.

To fix this bug: Add two line between } and pcl::io::savePCDFile(...).

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References:

PCL Documents: Using PCL in your own project