+#-----------------------------------------------------------------------
+# Builtins: targets
+#-----------------------------------------------------------------------
+
+add_custom_target(builtins)
+
+if (BUILTIN_GTKGLEXT)
+ include(${CMAKE_ROOT}/Modules/ExternalProject.cmake)
+
+ execute_process(COMMAND pkg-config --libs gdk-2.0 gtk+-2.0 glib-2.0 gl
+ OUTPUT_VARIABLE GTKGLEXT_DEPS_LDFLAGS
+ OUTPUT_STRIP_TRAILING_WHITESPACE
+ )
+ set(GTKGLEXT_DEPS_LDFLAGS "-lm ${GTKGLEXT_DEPS_LDFLAGS}")
+
+ ExternalProject_Add(gtkglext
+ GIT_REPOSITORY https://gitlab.gnome.org/illwieckz/gtkglext.git
+ GIT_TAG fixes
+ BUILD_IN_SOURCE ON
+ CONFIGURE_COMMAND NOCONFIGURE=1 ./autogen.sh
+ CONFIGURE_COMMAND && ./configure --prefix "${BUILTINS_INSTALL_DIR}" --disable-gtk-doc --disable-gtk-doc-html --disable-gtk-doc-pdf
+ BUILD_COMMAND $(MAKE) LDFLAGS=${GTKGLEXT_DEPS_LDFLAGS}
+ INSTALL_COMMAND $(MAKE) install
+ )
+
+# set(ENV{PKG_CONFIG_PATH} $ENV{PKG_CONFIG_PATH}:${BUILTINS_INSTALL_DIR}lib/pkgconfig/)
+# execute_process(COMMAND pkg-config --libs gtkglext-1.0
+# OUTPUT_VARIABLE GTKGLEXT_LDFLAGS
+# OUTPUT_STRIP_TRAILING_WHITESPACE
+# )
+# set(CMAKE_EXE_LINKER_FLAGS ${GTKGLEXT_LDFLAGS})
+
+# list(APPEND CMAKE_PREFIX_PATH "${BUILTINS_INSTALL_DIR}")
+ include_directories("${BUILTINS_INSTALL_DIR}/lib/gtkglext-1.0/include")
+ include_directories("${BUILTINS_INSTALL_DIR}/include/gtkglext-1.0")
+
+ add_dependencies(builtins gtkglext)
+ set_target_properties(gtkglext PROPERTIES EXCLUDE_FROM_ALL ON)
+endif ()
+
+if (BUNDLE_LIBRARIES AND EXISTS ${BUILTINS_LIB_DIR})
+ set(CMAKE_SKIP_BUILD_RPATH ON)
+endif()
+