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
106
107
108
109
110
111
112
113
114
115
116
|
/*
* Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
* Copyright (C) 2005 Nokia. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 COMPUTER, INC. OR
* 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 "FloatPoint.h"
#include "AffineTransform.h"
#include "TransformationMatrix.h"
#include "FloatConversion.h"
#include "IntPoint.h"
#include <limits>
#include <math.h>
namespace WebCore {
FloatPoint::FloatPoint(const IntPoint& p) : m_x(p.x()), m_y(p.y())
{
}
void FloatPoint::normalize()
{
float tempLength = length();
if (tempLength) {
m_x /= tempLength;
m_y /= tempLength;
}
}
float FloatPoint::length() const
{
return sqrtf(lengthSquared());
}
FloatPoint FloatPoint::matrixTransform(const AffineTransform& transform) const
{
double newX, newY;
transform.map(static_cast<double>(m_x), static_cast<double>(m_y), newX, newY);
return narrowPrecision(newX, newY);
}
FloatPoint FloatPoint::matrixTransform(const TransformationMatrix& transform) const
{
double newX, newY;
transform.map(static_cast<double>(m_x), static_cast<double>(m_y), newX, newY);
return narrowPrecision(newX, newY);
}
FloatPoint FloatPoint::narrowPrecision(double x, double y)
{
return FloatPoint(narrowPrecisionToFloat(x), narrowPrecisionToFloat(y));
}
float findSlope(const FloatPoint& p1, const FloatPoint& p2, float& c)
{
if (p2.x() == p1.x())
return std::numeric_limits<float>::infinity();
// y = mx + c
float slope = (p2.y() - p1.y()) / (p2.x() - p1.x());
c = p1.y() - slope * p1.x();
return slope;
}
bool findIntersection(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& d1, const FloatPoint& d2, FloatPoint& intersection)
{
float pOffset = 0;
float pSlope = findSlope(p1, p2, pOffset);
float dOffset = 0;
float dSlope = findSlope(d1, d2, dOffset);
if (dSlope == pSlope)
return false;
if (pSlope == std::numeric_limits<float>::infinity()) {
intersection.setX(p1.x());
intersection.setY(dSlope * intersection.x() + dOffset);
return true;
}
if (dSlope == std::numeric_limits<float>::infinity()) {
intersection.setX(d1.x());
intersection.setY(pSlope * intersection.x() + pOffset);
return true;
}
// Find x at intersection, where ys overlap; x = (c' - c) / (m - m')
intersection.setX((dOffset - pOffset) / (pSlope - dSlope));
intersection.setY(pSlope * intersection.x() + pOffset);
return true;
}
}
|
