Index: code/branches/presentationHS15/src/libraries/core/command/ArgumentCompletionFunctions.h
===================================================================
--- code/branches/presentationHS15/src/libraries/core/command/ArgumentCompletionFunctions.h	(revision 11044)
+++ code/branches/presentationHS15/src/libraries/core/command/ArgumentCompletionFunctions.h	(revision 11045)
@@ -161,6 +161,6 @@
 */
 #define ARGUMENT_COMPLETION_FUNCTION_DECLARATION(functionname) \
-    _CoreExport ArgumentCompleter* functionname(); \
-    _CoreExport ArgumentCompletionList acf_##functionname
+    ArgumentCompleter* functionname(); \
+    ArgumentCompletionList acf_##functionname
 
 /**
@@ -196,14 +196,14 @@
     namespace autocompletion
     {
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(fallback)();
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(groupsandcommands)(const std::string& fragment);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(subcommands)(const std::string& fragment, const std::string& group);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(command)(const std::string& fragment);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(hiddencommand)(const std::string& fragment);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(files)(const std::string& fragment);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingssections)();
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingsentries)(const std::string& fragment, const std::string& section);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingsvalue)(const std::string& fragment, const std::string& entry, const std::string& section);
-        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(tclthreads)();
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(fallback)();
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(groupsandcommands)(const std::string& fragment);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(subcommands)(const std::string& fragment, const std::string& group);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(command)(const std::string& fragment);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(hiddencommand)(const std::string& fragment);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(files)(const std::string& fragment);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingssections)();
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingsentries)(const std::string& fragment, const std::string& section);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(settingsvalue)(const std::string& fragment, const std::string& entry, const std::string& section);
+        _CoreExport ARGUMENT_COMPLETION_FUNCTION_DECLARATION(tclthreads)();
     }
 }
Index: code/branches/presentationHS15/src/orxonox/overlays/OverlayGroup.cc
===================================================================
--- code/branches/presentationHS15/src/orxonox/overlays/OverlayGroup.cc	(revision 11044)
+++ code/branches/presentationHS15/src/orxonox/overlays/OverlayGroup.cc	(revision 11045)
@@ -42,10 +42,25 @@
 namespace orxonox
 {
+    namespace autocompletion
+    {
+        /**
+            @brief Returns the names of all currently existing OverlayGroups.
+        */
+        ARGUMENT_COMPLETION_FUNCTION_DECLARATION(overlaygroupnames)();
+        ARGUMENT_COMPLETION_FUNCTION_IMPLEMENTATION(overlaygroupnames)()
+        {
+            ArgumentCompletionList names;
+            for (ObjectList<OverlayGroup>::iterator it = ObjectList<OverlayGroup>::begin(); it; ++it)
+                names.push_back(ArgumentCompletionListElement(it->getName(), getLowercase(it->getName())));
+            return names;
+        }
+    }
+
+    SetConsoleCommand("OverlayGroup", "toggleVisibility", &OverlayGroup::toggleVisibility).argumentCompleter(0, autocompletion::overlaygroupnames());
+    SetConsoleCommand("OverlayGroup", "show",             &OverlayGroup::show            ).argumentCompleter(0, autocompletion::overlaygroupnames());
+    SetConsoleCommand("OverlayGroup", "scaleGroup",       &OverlayGroup::scaleGroup      ).argumentCompleter(0, autocompletion::overlaygroupnames());
+    SetConsoleCommand("OverlayGroup", "scrollGroup",      &OverlayGroup::scrollGroup     ).argumentCompleter(0, autocompletion::overlaygroupnames());
+
     RegisterClass(OverlayGroup);
-
-    SetConsoleCommand("OverlayGroup", "toggleVisibility", &OverlayGroup::toggleVisibility);
-    SetConsoleCommand("OverlayGroup", "show", &OverlayGroup::show);
-    SetConsoleCommand("OverlayGroup", "scaleGroup",       &OverlayGroup::scaleGroup);
-    SetConsoleCommand("OverlayGroup", "scrollGroup",      &OverlayGroup::scrollGroup);
 
     OverlayGroup::OverlayGroup(Context* context)
