1 #ifndef SEEN_GEOM_BEZIER_UTILS_H
2 #define SEEN_GEOM_BEZIER_UTILS_H
4 /**
5 * \file
6 * \brief \todo brief description
7 *
8 * An Algorithm for Automatically Fitting Digitized Curves
9 * by Philip J. Schneider
10 * from "Graphics Gems", Academic Press, 1990
11 *
12 * Authors:
13 * Philip J. Schneider
14 * Lauris Kaplinski <lauris@ximian.com>
15 *
16 * Copyright (C) 1990 Philip J. Schneider
17 * Copyright (C) 2001 Lauris Kaplinski and Ximian, Inc.
18 *
19 * This library is free software; you can redistribute it and/or
20 * modify it either under the terms of the GNU Lesser General Public
21 * License version 2.1 as published by the Free Software Foundation
22 * (the "LGPL") or, at your option, under the terms of the Mozilla
23 * Public License Version 1.1 (the "MPL"). If you do not alter this
24 * notice, a recipient may use your version of this file under either
25 * the MPL or the LGPL.
26 *
27 * You should have received a copy of the LGPL along with this library
28 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 * You should have received a copy of the MPL along with this library
31 * in the file COPYING-MPL-1.1
32 *
33 * The contents of this file are subject to the Mozilla Public License
34 * Version 1.1 (the "License"); you may not use this file except in
35 * compliance with the License. You may obtain a copy of the License at
36 * http://www.mozilla.org/MPL/
37 *
38 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
39 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
40 * the specific language governing rights and limitations.
41 *
42 */
44 #include <2geom/point.h>
46 namespace Geom{
48 /* Bezier approximation utils */
49 Point bezier_pt(unsigned degree, Point const V[], double t);
51 int bezier_fit_cubic(Point bezier[], Point const data[], int len, double error);
53 int bezier_fit_cubic_r(Point bezier[], Point const data[], int len, double error,
54 unsigned max_beziers);
56 int bezier_fit_cubic_full(Point bezier[], int split_points[], Point const data[], int len,
57 Point const &tHat1, Point const &tHat2,
58 double error, unsigned max_beziers);
60 Point darray_left_tangent(Point const d[], unsigned const len);
61 Point darray_left_tangent(Point const d[], unsigned const len, double const tolerance_sq);
62 Point darray_right_tangent(Point const d[], unsigned const length, double const tolerance_sq);
64 template <typename iterator>
65 static void
66 cubic_bezier_poly_coeff(iterator b, Point *pc) {
67 double c[10] = {1,
68 -3, 3,
69 3, -6, 3,
70 -1, 3, -3, 1};
72 int cp = 0;
74 for(int i = 0; i < 4; i++) {
75 pc[i] = Point(0,0);
76 ++b;
77 }
78 for(int i = 0; i < 4; i++) {
79 --b;
80 for(int j = 0; j <= i; j++) {
81 pc[3 - j] += c[cp]*(*b);
82 cp++;
83 }
84 }
85 }
87 }
88 #endif /* !SEEN_GEOM_BEZIER_UTILS_H */
90 /*
91 Local Variables:
92 mode:c++
93 c-file-style:"stroustrup"
94 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
95 indent-tabs-mode:nil
96 fill-column:99
97 End:
98 */
99 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :