Use submodule for vtkGUISupportQt.

.gitmodules

@@ -22,3 +22,6 @@
 [submodule "Tests/Data"]
 	path = Tests/Data
 	url = https://github.com/ufz/ogs-data
+[submodule "ThirdParty/vtkGUISupportQt"]
+	path = ThirdParty/vtkGUISupportQt
+	url = https://github.com/ufz/vtkGUISupportQt.git

Applications/DataExplorer/CMakeLists.txt

-if(QT4_FOUND)
-	set(VTK_QT_VERSION 4 CACHE INTERNAL "")
-else()
-	set(VTK_QT_VERSION 5 CACHE INTERNAL "")
-endif()
-if(NOT TARGET vtkGUISupportQt)
-	add_subdirectory(VtkModules/Qt)
-endif()
-
 if(VTKFBXCONVERTER_FOUND)
 	add_definitions(-DVTKFBXCONVERTER_FOUND)
 	include_directories(${VTKFBXCONVERTER_INCLUDE_DIRS})

Applications/DataExplorer/DataExplorer.cmake

@@ -28,7 +28,6 @@ include_directories(
 	${CMAKE_CURRENT_SOURCE_DIR}/DataView/DiagramView
 	${CMAKE_CURRENT_SOURCE_DIR}/VtkVis
 	${CMAKE_CURRENT_SOURCE_DIR}/VtkAct
-	${CMAKE_CURRENT_SOURCE_DIR}/VtkModules/Qt
 )
 
 # Put moc files in a project folder

CMakeLists.txt

@@ -202,6 +202,7 @@ include_directories( SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/ThirdParty )
 include_directories( SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/ThirdParty/gtest/include )
 include_directories( SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/ThirdParty/autocheck/include )
 include_directories( SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/ThirdParty/tclap/include )
+include_directories(SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/ThirdParty/vtkGUISupportQt)
 
 add_subdirectory( Applications )
 add_subdirectory( AssemblerLib )

ThirdParty/CMakeLists.txt

@@ -46,3 +46,12 @@ if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/vtkdiff/CMakeLists.txt)
 	add_subdirectory(vtkdiff)
 	install (PROGRAMS $<TARGET_FILE:vtkdiff> DESTINATION bin COMPONENT ogs_extras)
 endif()
+
+if(NOT TARGET vtkGUISupportQt AND OGS_BUILD_GUI)
+	if(QT4_FOUND)
+		set(VTK_QT_VERSION 4 CACHE INTERNAL "")
+	else()
+		set(VTK_QT_VERSION 5 CACHE INTERNAL "")
+	endif()
+	add_subdirectory(${CMAKE_SOURCE_DIR}/ThirdParty/vtkGUISupportQt)
+endif()

vtkGUISupportQt @ b00c860c

+Subproject commit b00c860c6edb20436bc00e5b20bc47517786413a

scripts/cmake/SubmoduleSetup.cmake

@@ -15,6 +15,9 @@ set(REQUIRED_SUBMODULES
 if(OGS_BUILD_TESTS)
 	list(APPEND REQUIRED_SUBMODULES Tests/Data)
 endif()
+if(OGS_BUILD_GUI)
+	list(APPEND REQUIRED_SUBMODULES ThirdParty/vtkGUISupportQt)
+endif()
 
 foreach(SUBMODULE ${REQUIRED_SUBMODULES})
 	execute_process(