Sourcetype entity = | Line of pt * pt| Circle of pt * float| Arc of pt * float * float * float| Insert of string * pt * float * float| Dimension of pt * pt * pt
Sourcetype layer = {name : string;color : int;on : bool;
} Sourcetype t = {ents : (int * ent) list;layers : layer list;current : string;blocks : (string * (pt * ent list)) list;next : int;
} Sourceval ensure_layer : string -> t -> t Sourceval pick : t -> float -> pt -> int option Sourceval window : t -> pt -> pt -> crossing:bool -> int list