rem: coll_pairs.Add(key,cr);
add: coll_pairs.insert(CollPairMap::value_type(key, cr));
context:       void AddCollision(CollisionPair& cr, int id1, int id2)      {         // generate the merged 32 bit id and add collision report         int key;         get_merged_id(id1,id2,key);         coll_pairs.Add(key,cr);      };