f8ac7a2f7583bc2d7494312ae0099e22bc939e8c
1 /*
2 * rect.h - D2<Interval> specialization to Rect
3 *
4 * Copyright 2007 Michael Sloan <mgsloan@gmail.com>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it either under the terms of the GNU Lesser General Public
8 * License version 2.1 as published by the Free Software Foundation
9 * (the "LGPL") or, at your option, under the terms of the Mozilla
10 * Public License Version 1.1 (the "MPL"). If you do not alter this
11 * notice, a recipient may use your version of this file under either
12 * the MPL or the LGPL.
13 *
14 * You should have received a copy of the LGPL along with this library
15 * in the file COPYING-LGPL-2.1; if not, output to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 * You should have received a copy of the MPL along with this library
18 * in the file COPYING-MPL-1.1
19 *
20 * The contents of this file are subject to the Mozilla Public License
21 * Version 1.1 (the "License"); you may not use this file except in
22 * compliance with the License. You may obtain a copy of the License at
23 * http://www.mozilla.org/MPL/
24 *
25 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
26 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
27 * the specific language governing rights and limitations.
28 *
29 */
31 /* Authors of original rect class:
32 * Lauris Kaplinski <lauris@kaplinski.com>
33 * Nathan Hurst <njh@mail.csse.monash.edu.au>
34 * bulia byak <buliabyak@users.sf.net>
35 * MenTaLguY <mental@rydia.net>
36 */
38 #include <2geom/d2.h>
40 #ifndef _2GEOM_RECT
41 #define _2GEOM_RECT
43 #include <2geom/matrix.h>
44 #include <boost/optional/optional.hpp>
46 namespace Geom {
48 typedef D2<Interval> Rect;
50 Rect unify(const Rect &, const Rect &);
52 template<>
53 class D2<Interval> {
54 private:
55 Interval f[2];
56 public:
57 /* The default constructor creates an empty rect, constructed of two empty Intervals. (users rely on this!)
58 */
59 D2<Interval>() { f[X] = f[Y] = Interval(); }
61 D2<Interval>(Interval const &a, Interval const &b) {
62 f[X] = a;
63 f[Y] = b;
64 }
66 D2<Interval>(Point const & a, Point const & b) {
67 f[X] = Interval(a[X], b[X]);
68 f[Y] = Interval(a[Y], b[Y]);
69 }
71 inline Interval& operator[](unsigned i) { return f[i]; }
72 inline Interval const & operator[](unsigned i) const { return f[i]; }
74 inline Point min() const { return Point(f[X].min(), f[Y].min()); }
75 inline Point max() const { return Point(f[X].max(), f[Y].max()); }
77 /** returns the four corners of the rectangle in positive order
78 * (clockwise if +Y is up, anticlockwise if +Y is down) */
79 Point corner(unsigned i) const {
80 switch(i % 4) {
81 case 0: return Point(f[X].min(), f[Y].min());
82 case 1: return Point(f[X].max(), f[Y].min());
83 case 2: return Point(f[X].max(), f[Y].max());
84 default: return Point(f[X].min(), f[Y].max());
85 }
86 }
88 //We should probably remove these - they're coord sys gnostic
89 inline double top() const { return f[Y].min(); }
90 inline double bottom() const { return f[Y].max(); }
91 inline double left() const { return f[X].min(); }
92 inline double right() const { return f[X].max(); }
94 inline double width() const { return f[X].extent(); }
95 inline double height() const { return f[Y].extent(); }
97 /** returns a vector from min to max. */
98 inline Point dimensions() const { return Point(f[X].extent(), f[Y].extent()); }
99 inline Point midpoint() const { return Point(f[X].middle(), f[Y].middle()); }
101 inline double area() const { return f[X].extent() * f[Y].extent(); }
102 inline double maxExtent() const { return std::max(f[X].extent(), f[Y].extent()); }
104 inline bool isEmpty() const {
105 return f[X].isEmpty() || f[Y].isEmpty();
106 }
107 inline bool intersects(Rect const &r) const {
108 return f[X].intersects(r[X]) && f[Y].intersects(r[Y]);
109 }
110 inline bool contains(Rect const &r) const {
111 return f[X].contains(r[X]) && f[Y].contains(r[Y]);
112 }
113 inline bool contains(Point const &p) const {
114 return f[X].contains(p[X]) && f[Y].contains(p[Y]);
115 }
117 inline void expandTo(Point p) {
118 f[X].extendTo(p[X]); f[Y].extendTo(p[Y]);
119 }
120 inline void unionWith(Rect const &b) {
121 f[X].unionWith(b[X]); f[Y].unionWith(b[Y]);
122 }
124 inline void expandBy(double amnt) {
125 f[X].expandBy(amnt); f[Y].expandBy(amnt);
126 }
127 inline void expandBy(Point const p) {
128 f[X].expandBy(p[X]); f[Y].expandBy(p[Y]);
129 }
131 /** Transforms the rect by m. Note that it gives correct results only for scales and translates,
132 in the case of rotations, the area of the rect will grow as it cannot rotate. */
133 inline Rect operator*(Matrix const m) const {
134 return unify(Rect(corner(0) * m, corner(2) * m),
135 Rect(corner(1) * m, corner(3) * m));
136 }
137 };
139 inline Rect unify(Rect const & a, Rect const & b) {
140 return Rect(unify(a[X], b[X]), unify(a[Y], b[Y]));
141 }
143 inline Rect union_list(std::vector<Rect> const &r) {
144 if(r.empty()) return Rect(Interval(0,0), Interval(0,0));
145 Rect ret = r[0];
146 for(unsigned i = 1; i < r.size(); i++)
147 ret.unionWith(r[i]);
148 return ret;
149 }
151 inline boost::optional<Rect> intersect(Rect const & a, Rect const & b) {
152 boost::optional<Interval> x = intersect(a[X], b[X]);
153 boost::optional<Interval> y = intersect(a[Y], b[Y]);
154 return x && y ? boost::optional<Rect>(Rect(*x, *y)) : boost::optional<Rect>();
155 }
157 inline
158 double distanceSq( Point const& p, Rect const& rect )
159 {
160 double dx = 0, dy = 0;
161 if ( p[X] < rect.left() )
162 {
163 dx = p[X] - rect.left();
164 }
165 else if ( p[X] > rect.right() )
166 {
167 dx = rect.right() - p[X];
168 }
169 if ( p[Y] < rect.top() )
170 {
171 dy = rect.top() - p[Y];
172 }
173 else if ( p[Y] > rect.bottom() )
174 {
175 dy = p[Y] - rect.bottom();
176 }
177 return dx*dx + dy*dy;
178 }
180 inline
181 double distance( Point const& p, Rect const& rect )
182 {
183 return std::sqrt(distanceSq(p, rect));
184 }
187 } // end namespace Geom
189 #endif //_2GEOM_RECT
191 /*
192 Local Variables:
193 mode:c++
194 c-file-style:"stroustrup"
195 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
196 indent-tabs-mode:nil
197 fill-column:99
198 End:
199 */
200 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :