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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 */
30
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 */
37
38 #ifdef _2GEOM_D2 /*This is intentional: we don't actually want anyone to
39 include this, other than D2.h. If somone else tries, D2
40 won't be defined. If it is, this will already be included. */
41 #ifndef _2GEOM_RECT
42 #define _2GEOM_RECT
43
44 #include "matrix.h"
45 #include <boost/optional/optional.hpp>
46
47 namespace Geom {
48
49 typedef D2<Interval> Rect;
50
51 Rect unify(const Rect &, const Rect &);
52
53 template<>
54 class D2<Interval> {
55 private:
56 Interval f[2];
57 public:
58 D2<Interval>() { f[X] = f[Y] = Interval(0, 0); }
59
60 D2<Interval>(Interval const &a, Interval const &b) {
61 f[X] = a;
62 f[Y] = b;
63 }
64
65 D2<Interval>(Point const & a, Point const & b) {
66 f[X] = Interval(a[X], b[X]);
67 f[Y] = Interval(a[Y], b[Y]);
68 }
69
70 inline Interval& operator[](unsigned i) { return f[i]; }
71 inline Interval const & operator[](unsigned i) const { return f[i]; }
72
min()73 inline Point min() const { return Point(f[X].min(), f[Y].min()); }
max()74 inline Point max() const { return Point(f[X].max(), f[Y].max()); }
75
76 /** returns the four corners of the rectangle in positive order
77 * (clockwise if +Y is up, anticlockwise if +Y is down) */
corner(unsigned i)78 Point corner(unsigned i) const {
79 switch(i % 4) {
80 case 0: return Point(f[X].min(), f[Y].min());
81 case 1: return Point(f[X].max(), f[Y].min());
82 case 2: return Point(f[X].max(), f[Y].max());
83 default: return Point(f[X].min(), f[Y].max());
84 }
85 }
86
87 //We should probably remove these - they're coord sys gnostic
top()88 inline double top() const { return f[Y].min(); }
bottom()89 inline double bottom() const { return f[Y].max(); }
left()90 inline double left() const { return f[X].min(); }
right()91 inline double right() const { return f[X].max(); }
92
width()93 inline double width() const { return f[X].extent(); }
height()94 inline double height() const { return f[Y].extent(); }
95
96 /** returns a vector from min to max. */
dimensions()97 inline Point dimensions() const { return Point(f[X].extent(), f[Y].extent()); }
midpoint()98 inline Point midpoint() const { return Point(f[X].middle(), f[Y].middle()); }
99
area()100 inline double area() const { return f[X].extent() * f[Y].extent(); }
maxExtent()101 inline double maxExtent() const { return std::max(f[X].extent(), f[Y].extent()); }
102
isEmpty()103 inline bool isEmpty() const {
104 return f[X].isEmpty() && f[Y].isEmpty();
105 }
intersects(Rect const & r)106 inline bool intersects(Rect const &r) const {
107 return f[X].intersects(r[X]) && f[Y].intersects(r[Y]);
108 }
contains(Rect const & r)109 inline bool contains(Rect const &r) const {
110 return f[X].contains(r[X]) && f[Y].contains(r[Y]);
111 }
contains(Point const & p)112 inline bool contains(Point const &p) const {
113 return f[X].contains(p[X]) && f[Y].contains(p[Y]);
114 }
115
expandTo(Point p)116 inline void expandTo(Point p) {
117 f[X].extendTo(p[X]); f[Y].extendTo(p[Y]);
118 }
unionWith(Rect const & b)119 inline void unionWith(Rect const &b) {
120 f[X].unionWith(b[X]); f[Y].unionWith(b[Y]);
121 }
122
expandBy(double amnt)123 inline void expandBy(double amnt) {
124 f[X].expandBy(amnt); f[Y].expandBy(amnt);
125 }
expandBy(Point const p)126 inline void expandBy(Point const p) {
127 f[X].expandBy(p[X]); f[Y].expandBy(p[Y]);
128 }
129
130 /** Transforms the rect by m. Note that it gives correct results only for scales and translates,
131 in the case of rotations, the area of the rect will grow as it cannot rotate. */
132 inline Rect operator*(Matrix const m) const {
133 return unify(Rect(corner(0) * m, corner(2) * m),
134 Rect(corner(1) * m, corner(3) * m));
135 }
136 };
137
unify(Rect const & a,Rect const & b)138 inline Rect unify(Rect const & a, Rect const & b) {
139 return Rect(unify(a[X], b[X]), unify(a[Y], b[Y]));
140 }
141
union_list(std::vector<Rect> const & r)142 inline Rect union_list(std::vector<Rect> const &r) {
143 if(r.empty()) return Rect(Interval(0,0), Interval(0,0));
144 Rect ret = r[0];
145 for(unsigned i = 1; i < r.size(); i++)
146 ret.unionWith(r[i]);
147 return ret;
148 }
149
intersect(Rect const & a,Rect const & b)150 inline boost::optional<Rect> intersect(Rect const & a, Rect const & b) {
151 boost::optional<Interval> x = intersect(a[X], b[X]);
152 boost::optional<Interval> y = intersect(a[Y], b[Y]);
153 return x && y ? boost::optional<Rect>(Rect(*x, *y)) : boost::optional<Rect>();
154 }
155
156 }
157
158 #endif //_2GEOM_RECT
159 #endif //_2GEOM_D2
160 /*
161 Local Variables:
162 mode:c++
163 c-file-style:"stroustrup"
164 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
165 indent-tabs-mode:nil
166 fill-column:99
167 End:
168 */
169 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
170