1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
(* Graph viewer
* Copyright (C) 2010 Jérôme Vouillon
* Laboratoire PPS - CNRS Université Paris Diderot
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*)
open Scene
let pi = 4. *. atan 1.
let path_extent ctx fill stroke =
if stroke <> None then Cairo.stroke_extents ctx else Cairo.fill_extents ctx
let compute_extent ctx e =
Cairo.new_path ctx;
match e with
| Path (cmd, fill, stroke) ->
Array.iter
(fun c ->
match c with
| Move_to (x, y) -> Cairo.move_to ctx x y
| Curve_to (x1, y1, x2, y2, x3, y3) -> Cairo.curve_to ctx x1 y1 x2 y2 x3 y3)
cmd;
path_extent ctx fill stroke
| Ellipse (cx, cy, rx, ry, fill, stroke) ->
Cairo.save ctx;
Cairo.translate ctx cx cy;
Cairo.scale ctx rx ry;
Cairo.arc ctx 0. 0. 1. 0. (2. *. pi);
Cairo.restore ctx;
path_extent ctx fill stroke
| Polygon (points, fill, stroke) ->
Array.iteri
(fun i (x, y) -> if i = 0 then Cairo.move_to ctx x y else Cairo.line_to ctx x y)
points;
Cairo.close_path ctx;
path_extent ctx fill stroke
| Text (x, y, txt, (font, font_size), fill, stroke) ->
Cairo.select_font_face ctx font Cairo.FONT_SLANT_NORMAL Cairo.FONT_WEIGHT_NORMAL;
Cairo.set_font_size ctx font_size;
let ext = Cairo.text_extents ctx txt in
( x -. (ext.Cairo.text_width /. 2.) -. 5.
, y +. ext.Cairo.y_bearing -. 5.
, x +. (ext.Cairo.text_width /. 2.) +. 5.
, y +. ext.Cairo.y_bearing +. ext.Cairo.text_height +. 5. )
let compute ctx l = Array.map (fun e -> compute_extent ctx e) l
|
