But the top level CMakeLists.txt is designed for building all libraries and projects.
All binaries will be placed in `cocos2d_root/bin` and all libraries will be placed in `cocos2d_root/lib`.
Template will uses the libraries  in `lib`  folder.
Could the template in `cocos2d_root/template/multi-platform-cpp/HelloCpp` use the CMakeLists.txt in the top level folder?

Now we only static link the libraries in `lib` folder. As I know, `add_subdirectory` can't do this, right?
If it could, I think `minimal version` you did will make sense.:)