type interval =
| Bet of int * int(*

[|a,b|]

*)
| Bef of int(*

]|-oo,a|]

*)
| Aft of int(*

[|a,+oo|[

*)
| Nev(*

emptyset

*)
| Alw(*

N

*)

This type describes an interval of discrete points of time

val in_interval : int -> interval -> bool

test if an integer is in an interval

val min_interval : int -> interval -> int

The minimum between the integer argument and the beginning of the interval; returns the integer argument in the cases Nev and Alw

val max_interval : int -> interval -> int

The dual of min_interval

val min_tree : ( 'a -> interval ) -> 'a t -> int

The first moment of the tree to appear, not considering Nev and Alw

val max_tree : ( 'a -> interval ) -> 'a t -> int

The last moment of the tree to appear, not considering Nev and Alw

type 'a spec = (interval * 'a) list

A spec is a list of objects associated with a visibility interval

val assoq : int -> 'a spec -> 'a

returns the first element which is visible in the specification; raises Not_found if no element is visible

val max : ( 'a -> Num.t ) -> ('b * 'a) list -> Num.t

given a function to compute a numeric from an 'a, and a list of objects ('b,'a), return the maximal numeric from that list; intended to be used with width and height functions for objects and with a 'a spec list

val set_pos : ( Point.t -> 'a -> 'b ) -> Point.t -> 'a spec -> 'b spec

Given a function to move objects of type 'a, return a function to move functions of type 'a spec