cpdf-source/cpdfpresent.ml
John Whitington 265b4c71d0 more
2021-12-17 16:12:03 +00:00

60 lines
2.0 KiB
OCaml

(* Build PDF Presentations *)
open Pdfutil
let change_page_effect t d horizontal inward direction effect_duration page =
let checkname = function
| "Split" | "Blinds" | "Box" | "Wipe" | "Dissolve" | "Glitter" -> ()
| _ -> Cpdferror.error "Unknown presentation type"
in
let rest = page.Pdfpage.rest in
let transdict =
match t with
| None ->
Pdf.Dictionary []
| Some name ->
checkname name;
Pdf.Dictionary [("/S", Pdf.Name ("/" ^ name))]
in
let transdict = Pdf.add_dict_entry transdict "/D" (Pdf.Real effect_duration) in
let transdict =
match t with
| Some ("Split" | "Blinds") ->
Pdf.add_dict_entry
transdict "/Dm" (Pdf.Name (if horizontal then "/H" else "/V"))
| _ -> transdict
in
let transdict =
match t with
| Some ("Split" | "Box") ->
Pdf.add_dict_entry
transdict "/M" (Pdf.Name (if inward then "/I" else "/O"))
| _ -> transdict
in
let transdict =
match t with
| Some ("Wipe" | "Glitter") ->
Pdf.add_dict_entry transdict "/Di" (Pdf.Integer direction)
| _ -> transdict
in
let rest = Pdf.add_dict_entry rest "/Trans" transdict in
let rest =
match d with
| None -> Pdf.remove_dict_entry rest "/Dur"
| Some delay -> Pdf.add_dict_entry rest "/Dur" (Pdf.Real delay)
in
{page with Pdfpage.rest = rest}
let presentation range t d h i dir effect_dur pdf =
let pages = Pdfpage.pages_of_pagetree pdf in
let pages' =
map2
(fun page num ->
if mem num range
then change_page_effect t d h i dir effect_dur page
else page)
pages
(indx pages)
in
Pdfpage.change_pages true pdf pages'