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