1/*
2 * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above
9 * copyright notice, this list of conditions and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following
13 * disclaimer in the documentation and/or other materials
14 * provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
19 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
20 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
21 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
27 * OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#pragma once
31
32#include <wtf/Vector.h>
33
34namespace WebCore {
35
36template <typename T>
37class ShapeInterval {
38 WTF_MAKE_FAST_ALLOCATED;
39public:
40 ShapeInterval()
41 : m_x1(-1)
42 , m_x2(-2)
43 {
44 // The initial values of m_x1,x2 don't matter (unless you're looking
45 // at them in the debugger) so long as isUndefined() is true.
46 ASSERT(isUndefined());
47 }
48
49 ShapeInterval(T x1, T x2)
50 : m_x1(x1)
51 , m_x2(x2)
52 {
53 ASSERT(x2 >= x1);
54 }
55
56 bool isUndefined() const { return m_x2 < m_x1; }
57 T x1() const { return isUndefined() ? 0 : m_x1; }
58 T x2() const { return isUndefined() ? 0 : m_x2; }
59 T width() const { return isUndefined() ? 0 : m_x2 - m_x1; }
60 bool isEmpty() const { return isUndefined() ? true : m_x1 == m_x2; }
61
62 void set(T x1, T x2)
63 {
64 ASSERT(x2 >= x1);
65 m_x1 = x1;
66 m_x2 = x2;
67 }
68
69 bool overlaps(const ShapeInterval<T>& interval) const
70 {
71 if (isUndefined() || interval.isUndefined())
72 return false;
73 return x2() >= interval.x1() && x1() <= interval.x2();
74 }
75
76 bool contains(const ShapeInterval<T>& interval) const
77 {
78 if (isUndefined() || interval.isUndefined())
79 return false;
80 return x1() <= interval.x1() && x2() >= interval.x2();
81 }
82
83 void unite(const ShapeInterval<T>& interval)
84 {
85 if (interval.isUndefined())
86 return;
87 if (isUndefined())
88 set(interval.x1(), interval.x2());
89 else
90 set(std::min<T>(x1(), interval.x1()), std::max<T>(x2(), interval.x2()));
91 }
92
93 bool operator==(const ShapeInterval<T>& other) const { return x1() == other.x1() && x2() == other.x2(); }
94 bool operator!=(const ShapeInterval<T>& other) const { return !operator==(other); }
95
96private:
97 T m_x1;
98 T m_x2;
99};
100
101typedef ShapeInterval<int> IntShapeInterval;
102typedef ShapeInterval<float> FloatShapeInterval;
103
104typedef Vector<IntShapeInterval> IntShapeIntervals;
105typedef Vector<FloatShapeInterval> FloatShapeIntervals;
106
107} // namespace WebCore
108