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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
/*
* Copyright (C) 2008 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "FloatQuad.h"
#include <algorithm>
using std::max;
using std::min;
namespace WebCore {
static inline float min4(float a, float b, float c, float d)
{
return min(min(a, b), min(c, d));
}
static inline float max4(float a, float b, float c, float d)
{
return max(max(a, b), max(c, d));
}
inline float dot(const FloatSize& a, const FloatSize& b)
{
return a.width() * b.width() + a.height() * b.height();
}
inline bool isPointInTriangle(const FloatPoint& p, const FloatPoint& t1, const FloatPoint& t2, const FloatPoint& t3)
{
// Compute vectors
FloatSize v0 = t3 - t1;
FloatSize v1 = t2 - t1;
FloatSize v2 = p - t1;
// Compute dot products
float dot00 = dot(v0, v0);
float dot01 = dot(v0, v1);
float dot02 = dot(v0, v2);
float dot11 = dot(v1, v1);
float dot12 = dot(v1, v2);
// Compute barycentric coordinates
float invDenom = 1.0f / (dot00 * dot11 - dot01 * dot01);
float u = (dot11 * dot02 - dot01 * dot12) * invDenom;
float v = (dot00 * dot12 - dot01 * dot02) * invDenom;
// Check if point is in triangle
return (u >= 0) && (v >= 0) && (u + v <= 1);
}
FloatRect FloatQuad::boundingBox() const
{
float left = min4(m_p1.x(), m_p2.x(), m_p3.x(), m_p4.x());
float top = min4(m_p1.y(), m_p2.y(), m_p3.y(), m_p4.y());
float right = max4(m_p1.x(), m_p2.x(), m_p3.x(), m_p4.x());
float bottom = max4(m_p1.y(), m_p2.y(), m_p3.y(), m_p4.y());
return FloatRect(left, top, right - left, bottom - top);
}
bool FloatQuad::isRectilinear() const
{
return (m_p1.x() == m_p2.x() && m_p2.y() == m_p3.y() && m_p3.x() == m_p4.x() && m_p4.y() == m_p1.y())
|| (m_p1.y() == m_p2.y() && m_p2.x() == m_p3.x() && m_p3.y() == m_p4.y() && m_p4.x() == m_p1.x());
}
bool FloatQuad::containsPoint(const FloatPoint& p) const
{
return isPointInTriangle(p, m_p1, m_p2, m_p3) || isPointInTriangle(p, m_p1, m_p3, m_p4);
}
// Note that we only handle convex quads here.
bool FloatQuad::containsQuad(const FloatQuad& other) const
{
return containsPoint(other.p1()) && containsPoint(other.p2()) && containsPoint(other.p3()) && containsPoint(other.p4());
}
} // namespace WebCore
|
