anchor.diff:  %%====================================================================
   %% Internal functions
   %%====================================================================
  -
  -spawn_entities(BcEntityConfig, #state{entities = BcEntities,
  -								  map = BcMap,
  -								  spawn_vertices = BcVertices} = State) ->
  -	EntitySize = bc_entity_config:size(BcEntityConfig),
  -	QueryRes = bc_map:query_collisions(BcMap, BcVertices),
  -	%% TODO spawn entities
  -	ok.
   
   base_num(BaseBcVertices, BcMap) ->
   	BaseBcVertex = lists:nth(1, BaseBcVertices),
  
positive.code: 			{ok, Num, State}
  	end.
  
  spawn_vertices(#state{base_num = BaseNum,
  					  spawn_vertices = SpawnBcVertices,
  					  map = BcMap} = State) ->
  	case SpawnBcVertices of
  		undefined ->
  			BcVertices = case BaseNum of
  							 1 -> bc_map:base1_spawn_vertices(BcMap);
  
negative.code: 	case bc_entities:entity_config(EntityType) of
  		{ok, BcEntityConfig} ->
  			{ok, BaseNum, State1} = player_num(State),
  			{ok, SpawnBcVertices, State2} = spawn_matrix(State1),
  			spawn_entities(EntityType, State2),
  			{ok, State2};
  		error ->
  