Added assert to make sure the lod node is used correctly.

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@9105 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/graphics/lod_node.cpp

@@ -86,6 +86,7 @@ void LODNode::add(int level, scene::ISceneNode* node, bool reparent)
     // and the location is disapparition needs to be deterministic
     if (m_detail.size() > 0)
     {
+        assert(m_detail.back()<level*level);
         m_detail[m_detail.size() - 1] += (int)(((rand()%1000)-500)/500.0f*(m_detail[m_detail.size() - 1]*0.2f));
     }