# download some headers missing from Windows IF(NOT EXISTS ${POLYCODE_DEPS_DOWNLOAD_DIR}/glext.h) MESSAGE("Downloading http://www.opengl.org/registry/api/glext.h") FILE(DOWNLOAD http://www.opengl.org/registry/api/glext.h ${POLYCODE_DEPS_DOWNLOAD_DIR}/glext.h SHOW_PROGRESS) ENDIF() ADD_CUSTOM_TARGET(glext COMMAND ${CMAKE_COMMAND} -E copy_if_different ${POLYCODE_DEPS_DOWNLOAD_DIR}/glext.h ${POLYCODE_DEPS_CORE_PREFIX}/include/GL/glext.h)