if(APPLE) add_subdirectory(osx) elseif(BUILD_TARGET STREQUAL "RPI") add_subdirectory(rpi) elseif(X11XRANDR_FOUND) add_subdirectory(x11) elseif(WIN32) add_subdirectory(win) endif() add_subdirectory(dummy) find_all_sources(. SRC) add_sources(${SRC})