cpdf-source/cpdftexttopdf.ml

64 lines
2.4 KiB
OCaml

open Pdfutil
let rec of_utf8_with_newlines fontpack fontsize t =
let items = ref [] in
let currfont = ref ~-1 in
let codepoints = Pdftext.codepoints_of_utf8 t in
let currtext = ref [] in
let process_codepoints cs =
iter
(fun u ->
match Cpdfembed.get_char fontpack u with
| Some (c, n, f) ->
(*Printf.printf "Charcode %i, font number %i\n" c n;*)
begin if n <> !currfont then
begin
if !currtext <> [] then items := Cpdftype.Text (rev !currtext)::!items;
currtext := [];
currfont := n;
items := Cpdftype.Font (f, fontsize)::!items;
currtext := char_of_int c::!currtext;
end
else
currtext := char_of_int c::!currtext
end
| None -> Printf.printf "No glyph for unicode U+%04X in this font\n" u)
cs;
items := Cpdftype.Text (rev !currtext)::!items
in
let buf = ref [] in
List.iter
(function
| 10 (*'\n'*) ->
let c = rev !buf in
if c <> [] then process_codepoints c;
items := Cpdftype.NewLine::!items;
buf := []
| 13 (*'\r'*) -> ()
| x ->
buf := x::!buf)
codepoints;
(* Do last one *)
let c = rev !buf in
if c <> [] then process_codepoints c;
rev !items
let typeset ~papersize ~font ~fontsize text =
let pdf = Pdf.empty () in
let codepoints = setify (Pdftext.codepoints_of_utf8 (Pdfio.string_of_bytes text)) in
let fontpack =
match font with
| Cpdfembed.PreMadeFontPack t -> t
| Cpdfembed.EmbedInfo {fontfile; fontname; encoding} ->
Cpdfembed.embed_truetype pdf ~fontfile ~fontname ~codepoints ~encoding
| Cpdfembed.ExistingNamedFont ->
raise (Pdf.PDFError "Can't use existing named font for text-to-PDF")
in
let instrs = of_utf8_with_newlines fontpack fontsize (Pdfio.string_of_bytes text) in
let margin = Pdfunits.points (Pdfpaper.width papersize) (Pdfpaper.unit papersize) /. 15. in
let firstfont = hd (keep (function Cpdftype.Font _ -> true | _ -> false) instrs) in
let instrs = [firstfont; Cpdftype.BeginDocument] @ instrs in
let pages = Cpdftype.typeset margin margin margin margin papersize pdf instrs in
let pdf, pageroot = Pdfpage.add_pagetree pages pdf in
Pdfpage.add_root pageroot [] pdf