• Download Eigen from its homepage: http:https://eigen.tuxfamily.org/
• Extract Eigen to a convenient location.

If you want to use the GUI of g2o

• Download and install the Qt SDK: http:https://qt.nokia.com/downloads/
• Download and compile libQGLViewer: http:https://www.libqglviewer.com/

• Create a folder called "build" below the g2o source folder
• Start cmake and select the source folder of g2o and the build folder created in the first step
• Hit configure, select the appropriate Visual Studio Version, and click finish.
• cmake will probably complain about missing Eigen. Set the variable G2O_EIGEN3_INCLUDE to the folder containing Eigen.
• Hit configure to re-run the cmake configuration with the correct location for Eigen.
• cmake should run through without errors and after hitting generate the Visual Studio solution is created

If QGLViewer is available, then set the variables QGLVIEWER_INCLUDE_DIR and QGLVIEWER_LIBRARY.

msbuild g2o.sln /p:Configuration=RelWithDebInfo /maxcpucount