UPBGE: Forbid setParent to an object in an inactive layer

Previously object was able to be parented between active
and inactive objects. But this was introducing big troubles
when adding an inactive object with active object children.

To solve this issue the inter layer parenting is disallowed.
Only active objects can be parented to active objects and
the same for inactive objects.

Author: youle31

Diff for: source/gameengine/Ketsji/KX_GameObject.cpp

@@ -318,8 +318,13 @@ void KX_GameObject::SetParent(KX_GameObject* obj, bool addToCompound, bool ghost
 		obj->GetSGNode() &&		// object is not zombi
 		GetSGNode()->GetSGParent() != obj->GetSGNode() &&	// not already parented to same object
 		!GetSGNode()->IsAncessor(obj->GetSGNode()) && 		// no parenting loop
-		this != obj)										// not the object itself
+		this != obj) // not the object itself
 	{
+		if (!(GetScene()->GetInactiveList()->SearchValue(obj) != GetScene()->GetObjectList()->SearchValue(this))) {
+			std::cout << "Warning: Child and Parent are not in the same gameobjects list (active or inactive).\n" <<
+				"This operation is forbidden." << std::endl;
+			return;
+		}
 		// Make sure the objects have some scale
 		MT_Vector3 scale1 = NodeGetWorldScaling();
 		MT_Vector3 scale2 = obj->NodeGetWorldScaling();
@@ -3530,6 +3535,7 @@ PyObject *KX_GameObject::PySetParent(PyObject *args)
 	}
 	if (!ConvertPythonToGameObject(logicmgr, pyobj, &obj, true, "gameOb.setParent(obj): KX_GameObject"))
 		return NULL;
+
 	if (obj)
 		SetParent(obj, addToCompound, ghost);
 	Py_RETURN_NONE;