Added tetgen 1.5.0 as a submodule.

This module is automatically checked out when OGS_BUILD_GUI=ON and the executable
gets packaged with the Data Explorer.

Tetgen source is hosted at https://github.com/ufz/tetgen.git

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "ThirdParty/VtkOsgConverter"]
 	path = ThirdParty/VtkOsgConverter
 	url = git://github.com/ufz-vislab/VtkOsgConverter.git
+[submodule "ThirdParty/tetgen"]
+	path = ThirdParty/tetgen
+	url = https://github.com/ufz/tetgen.git

ThirdParty/CMakeLists.txt

@@ -33,3 +33,13 @@ IF(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/VtkOsgConverter/CMakeLists.txt
 	AND OGS_USE_OPTIONAL_SUBMODULES)
 	ADD_SUBDIRECTORY(VtkOsgConverter)
 ENDIF()
+
+# tetgen
+IF(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/tetgen/CMakeLists.txt)
+	ADD_SUBDIRECTORY(tetgen)
+	IF(APPLE)
+		INSTALL (PROGRAMS $<TARGET_FILE:tetgen> DESTINATION ogs-gui.app/Contents/MacOS COMPONENT ogs_extras)
+	ELSE()
+		INSTALL (PROGRAMS $<TARGET_FILE:tetgen> DESTINATION bin COMPONENT ogs_extras)
+	ENDIF()
+ENDIF()

tetgen @ 9c4b70d4

+Subproject commit 9c4b70d479c6f67cb9e16dbe65f81ec3b821acad

scripts/cmake/SubmoduleSetup.cmake

@@ -9,6 +9,10 @@ SET(REQUIRED_SUBMODULES
 	${OGS_ADDITIONAL_SUBMODULES_TO_CHECKOUT}
 )
 
+IF(OGS_BUILD_GUI)
+	SET(REQUIRED_SUBMODULES ${REQUIRED_SUBMODULES} ThirdParty/tetgen)
+ENDIF()
+
 FOREACH(SUBMODULE ${REQUIRED_SUBMODULES})
 	IF(WIN32)
 		SET(SUBMODULE_STATE 1)
@@ -34,4 +38,4 @@ FOREACH(SUBMODULE ${REQUIRED_SUBMODULES})
 			WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
 		)
 	ENDIF()
-ENDFOREACH()
+ENDFOREACH()
\ No newline at end of file