SLAM14讲错误笔记（第六讲G2O篇）_by not providing "findluagoogle.cmake" in cmake_mo

错误一：g2oCurveFitting程序cmake报错

报错信息：

CMake Error at CMakeLists.txt:12 (find_package):
  By not providing "FindG2O.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "G2O", but
  CMake did not find one.
 
  Could not find a package configuration file provided by "G2O" with any of
  the following names:
 
    G2OConfig.cmake
    g2o-config.cmake
 
  Add the installation prefix of "G2O" to CMAKE_PREFIX_PATH or set "G2O_DIR"
  to a directory containing one of the above files.  If "G2O" provides a
  separate development package or SDK, be sure it has been installed.
 
 
-- Configuring incomplete, errors occurred!
See also "/home/chi/slambook2/ch6/g2oCurveFitting/build/CMakeFiles/CMakeOutput.log".

错误原因：

        参考了凌啸天与zhiwei121等人的博客，原因应该是没有找到相应的库文件所致。

解决方法：

        根据zhiwei121的解决方法，将要保证build文件夹与cmake的文件夹在同一级，在高翔博士的代码中是附有cmake文件的。

        对应的CMakeLists.txt中

list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)

也要加入自己写的CMakeLists.txt中，cmake ..通过。

注1：按笔者贫瘠的编程知识，这种解决方法更像是通过外挂文件“解决”了库文件索引问题，似乎是治标不治本，凌啸天的处理方法可能更好，这里没有继续尝试了。

注2：根据youxiaogeo的解决方法，直接在CMakeLists.txt文件中添加G2O的库路径也可解决问题，如下所示：

LIST( APPEND CMAKE_MODULE_PATH /XXX/g2o/cmake_modules )
SET( G2O_ROOT /home/xxx/g2o )
FIND_PACKAGE( G2O REQUIRED )