KHtml

ColorDistance.cpp
1 /*
2  Copyright (C) 2007 Eric Seidel <[email protected]>
3 
4  This file is part of the WebKit project
5 
6  This library is free software; you can redistribute it and/or
7  modify it under the terms of the GNU Library General Public
8  License as published by the Free Software Foundation; either
9  version 2 of the License, or (at your option) any later version.
10 
11  This library is distributed in the hope that it will be useful,
12  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  Library General Public License for more details.
15 
16  You should have received a copy of the GNU Library General Public License
17  along with this library; see the file COPYING.LIB. If not, write to
18  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19  Boston, MA 02110-1301, USA.
20  */
21 
22 #if ENABLE(SVG)
23 #include "ColorDistance.h"
24 #include "Color.h"
25 #include <wtf/MathExtras.h>
26 
27 namespace WebCore
28 {
29 
30 ColorDistance::ColorDistance()
31  : m_redDiff(0)
32  , m_greenDiff(0)
33  , m_blueDiff(0)
34 {
35 }
36 
37 ColorDistance::ColorDistance(const Color &fromColor, const Color &toColor)
38  : m_redDiff(toColor.red() - fromColor.red())
39  , m_greenDiff(toColor.green() - fromColor.green())
40  , m_blueDiff(toColor.blue() - fromColor.blue())
41 {
42 }
43 
44 ColorDistance::ColorDistance(int redDiff, int greenDiff, int blueDiff)
45  : m_redDiff(redDiff)
46  , m_greenDiff(greenDiff)
47  , m_blueDiff(blueDiff)
48 {
49 }
50 
51 static inline int clampColorValue(int v)
52 {
53  if (v > 255) {
54  v = 255;
55  } else if (v < 0) {
56  v = 0;
57  }
58  return v;
59 }
60 
61 ColorDistance ColorDistance::scaledDistance(float scaleFactor) const
62 {
63  return ColorDistance(static_cast<int>(scaleFactor * m_redDiff),
64  static_cast<int>(scaleFactor * m_greenDiff),
65  static_cast<int>(scaleFactor * m_blueDiff));
66 }
67 
68 Color ColorDistance::addColorsAndClamp(const Color &first, const Color &second)
69 {
70  return Color(clampColorValue(first.red() + second.red()),
71  clampColorValue(first.green() + second.green()),
72  clampColorValue(first.blue() + second.blue()));
73 }
74 
75 Color ColorDistance::addToColorAndClamp(const Color &color) const
76 {
77  return Color(clampColorValue(color.red() + m_redDiff),
78  clampColorValue(color.green() + m_greenDiff),
79  clampColorValue(color.blue() + m_blueDiff));
80 }
81 
82 bool ColorDistance::isZero() const
83 {
84  return (m_redDiff == 0 && m_blueDiff == 0 && m_greenDiff == 0);
85 }
86 
87 float ColorDistance::distance() const
88 {
89  // This is just a simple distance calculation, not respecting color spaces
90  return sqrtf(m_redDiff * m_redDiff + m_blueDiff * m_blueDiff + m_greenDiff * m_greenDiff);
91 }
92 
93 }
94 
95 #endif
This file is part of the KDE documentation.
Documentation copyright © 1996-2021 The KDE developers.
Generated on Mon Oct 25 2021 22:48:11 by doxygen 1.8.11 written by Dimitri van Heesch, © 1997-2006

KDE's Doxygen guidelines are available online.