anchor.diff:  -spec vertices(BcEntity :: entity()) -> [bc_vertex:vertex()].
   vertices(BcEntity) ->
   	maps:get(vertices, BcEntity).
  +
  +-spec set_vertices(BcVertices :: [bc_vertex:vertex()], BcEntity :: entity()) -> entity().
  +set_vertices(BcVertices, BcEntity) ->
  +	maps:update(vertices, BcVertices, BcEntity).
   
   -spec to_collision(BcEntity :: entity()) -> bc_collision:collision().
   to_collision(BcEntity) ->
  
positive.code: player_id(BcEntity)->
  	maps:get(player_id, BcEntity).
  
  -spec team(BcEntity :: entity()) -> integer().
  team(BcEntity) ->
  	maps:get(team, BcEntity).
  
  -spec entity_type(BcEntity :: entity()) -> integer().
  entity_type(BcEntity) ->
  
negative.code: -export([init/6, 
  		 init/7, 
  		 uuid/1, 
  		 player_id/1,
  		 set_player_id/1, 
  		 team/1, 
  		 set_team/2,
  		 entity_type/1, 
  		 health/1, 
  		 set_health/2,
  		 ai_fsm/1,
  		 vertices/1,
  		 set_vertices/2,
  		 to_collision/1,
  		 to_tuple/1,
  		 from_tuple/1]).
  