Change include path of static library

Question

I want to make a static library from a project of mine such that I can use it like this in other projects:

#include <MonoEngine/engine.hpp>

However right now I have a src folder in between:

#include <MonoEngine/src/engine.hpp>

How can I build the static library with CMake such that I can omit the src/?

This is roughly how my library folder is structured.

monoEngine
|-src
| |-engine.hpp
| |-engine.cpp
| |-subfolder1
|   |-file.hpp
|   |-file.cpp
|-CMakeLists.txt

Answer 1

Create subfolder include and place all your headers in there and add that folder to your include path:

monoEngine
|-include
| |-MonoEngine
| | |-engine.hpp 
| | |-subfolder1
| |   |-public.hpp
|-src
| |-engine.cpp
| |-subfolder1
|   |-private.hpp (will not be shared with third parties)
|   |-file.cpp
|-CMakeLists.txt

That way headers in the include will provide the public interface of your library, while headers in the src-directory will not be exposed to third parties using your library. That's the common approach if build a library.

Addendum:

Since you asked in the comments below how to use this with CMake, a simple CMakeLists.txt could look like this (untested):

project( your_project )
cmake_minimum_required( VERSION 3.0 )

set( SRC_LIST 
    include/MonoEngine/engine.hpp
    include/MonoEngine/subfolder1/public.hpp
    src/engine.cpp
    src/subfolder1/file.cpp
    src/subfolder1/private.h )

add_library( your_lib ${SRC_LIST} )
target_include_directories( your_lib PUBLIC ${CMAKE_SOURCE_DIR}/include ${CMAKE_SOURCE_DIR}/src )

# and then optional parameters:
# target_compile_options( your_lib ... )
# target_link_libraries( your_lib ... )
# install(TARGETS your_lib ... )