cmakelists for opengl, glut on mac(practical)

CMakeLists.txt

cmake_minimum_required(VERSION 2.8.4)
project(helloworld)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

#########################################################
# Include Files
#########################################################
set(SOURCE_FILES main.cpp Cool.cpp)
add_executable(helloworld ${SOURCE_FILES})

IF (APPLE)
   include_directories (/System/Library/Frameworks)
   find_library (GLUT_LIBRARY GLUT)
   find_library (OpenGL_LIBRARY OpenGL)
   mark_as_advanced (GLUT_LIBRARY
                     OpenGL_LIBRARY)
   set (EXTRA_LIBS ${GLUT_LIBRARY} ${OpenGL_LIBRARY})
ENDIF (APPLE)

target_link_libraries(helloworld ${EXTRA_LIBS})