include/basegfx/color/bcolor.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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  15  *   License, Version 2.0 (the "License"); you may not use this file
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  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #pragma once
  21
  22 #include <sal/config.h>
  23
  24 #include <algorithm>
  25 #include <ostream>
  26
  27 #include <basegfx/tuple/b3dtuple.hxx>
  28 #include <basegfx/basegfxdllapi.h>
  29
  30 namespace basegfx
  31 {
  32     /** Base Color class with three double values
  33
  34         This class derives all operators and common handling for
  35         a 3D data class from B3DTuple. All necessary extensions
  36         which are special for colors will be added here.
  37
  38         @see B3DTuple
  39     */
  40     class SAL_WARN_UNUSED BASEGFX_DLLPUBLIC BColor : public B3DTuple
  41     {
  42         bool bAutomatic = false;
  43
  44     public:
  45         /** Create a Color with red, green and blue components from [0.0 to 1.0]
  46
  47             The color is initialized to (0.0, 0.0, 0.0)
  48         */
  49         BColor()
  50         {}
  51
  52         /** Create a 3D Color
  53
  54             @param fRed
  55             @param fGreen
  56             @param fBlue
  57             These parameters are used to initialize the red, green and blue intensities of the color
  58         */
  59         BColor(double fRed, double fGreen, double fBlue)
  60         :   B3DTuple(fRed, fGreen, fBlue)
  61         {}
  62
  63         /** Create a 3D Color
  64
  65             @param fLuminosity
  66             The parameter is used to initialize the red, green and blue intensities of the color
  67         */
  68         explicit BColor(double fLuminosity)
  69         :   B3DTuple(fLuminosity, fLuminosity, fLuminosity)
  70         {}
  71
  72         /** constructor with tuple to allow copy-constructing
  73             from B3DTuple-based classes
  74         */
  75         BColor(const ::basegfx::B3DTuple& rTuple)
  76         :   B3DTuple(rTuple)
  77         {}
  78
  79         // data access read
  80         double getRed() const { return mnX; }
  81         double getGreen() const { return mnY; }
  82         double getBlue() const { return mnZ; }
  83         bool isAutomatic() const { return bAutomatic; }
  84
  85         // data access write
  86         void setRed(double fNew) { mnX = fNew; }
  87         void setGreen(double fNew) { mnY = fNew; }
  88         void setBlue(double fNew) { mnZ = fNew; }
  89         void setAutomatic(bool bNew) { bAutomatic = bNew; }
  90
  91         /** *=operator to allow usage from BColor, too
  92         */
  93         BColor& operator*=( const BColor& rPnt )
  94         {
  95             mnX *= rPnt.mnX;
  96             mnY *= rPnt.mnY;
  97             mnZ *= rPnt.mnZ;
  98             return *this;
  99         }
 100
 101         /** *=operator to allow usage from BColor, too
 102         */
 103         BColor& operator*=(double t)
 104         {
 105             mnX *= t;
 106             mnY *= t;
 107             mnZ *= t;
 108             return *this;
 109         }
 110
 111         /** assignment operator to allow assigning the results
 112             of B3DTuple calculations
 113         */
 114         BColor& operator=( const ::basegfx::B3DTuple& rVec )
 115         {
 116             mnX = rVec.getX();
 117             mnY = rVec.getY();
 118             mnZ = rVec.getZ();
 119             return *this;
 120         }
 121
 122         // luminance
 123         double luminance() const
 124         {
 125             const double fRedWeight(77.0 / 256.0);      // 0.30
 126             const double fGreenWeight(151.0 / 256.0);   // 0.59
 127             const double fBlueWeight(28.0 / 256.0);     // 0.11
 128
 129             return (mnX * fRedWeight + mnY * fGreenWeight + mnZ * fBlueWeight);
 130         }
 131
 132         // distances in color space
 133         double getDistanceRed(const BColor& rColor) const { return (getRed() > rColor.getRed() ? getRed() - rColor.getRed() : rColor.getRed() - getRed()); }
 134         double getDistanceGreen(const BColor& rColor) const { return (getGreen() > rColor.getGreen() ? getGreen() - rColor.getGreen() : rColor.getGreen() - getGreen()); }
 135         double getDistanceBlue(const BColor& rColor) const { return (getBlue() > rColor.getBlue() ? getBlue() - rColor.getBlue() : rColor.getBlue() - getBlue()); }
 136
 137         double getDistance(const BColor& rColor) const
 138         {
 139             const double fDistR(getDistanceRed(rColor));
 140             const double fDistG(getDistanceGreen(rColor));
 141             const double fDistB(getDistanceBlue(rColor));
 142
 143             return std::hypot(fDistR, fDistG, fDistB);
 144         }
 145
 146         double getMaximumDistance(const BColor& rColor) const
 147         {
 148             const double fDistR(getDistanceRed(rColor));
 149             const double fDistG(getDistanceGreen(rColor));
 150             const double fDistB(getDistanceBlue(rColor));
 151
 152             double fRetval(std::max(fDistR, fDistG));
 153             return std::max(fRetval, fDistB);
 154         }
 155
 156         // clamp color to [0.0..1.0] values in all three intensity components
 157         BColor& clamp()
 158         {
 159             mnX = std::clamp(mnX, 0.0, 1.0);
 160             mnY = std::clamp(mnY, 0.0, 1.0);
 161             mnZ = std::clamp(mnZ, 0.0, 1.0);
 162             return *this;
 163         }
 164
 165         void invert()
 166         {
 167             mnX = 1.0 - mnX;
 168             mnY = 1.0 - mnY;
 169             mnZ = 1.0 - mnZ;
 170         }
 171
 172         static const BColor& getEmptyBColor()
 173         {
 174             static BColor const singleton;
 175             return singleton;
 176         }
 177
 178     };
 179
 180     template<typename charT, typename traits>
 181     std::basic_ostream<charT, traits> & operator <<(
 182         std::basic_ostream<charT, traits> & stream, BColor const & color)
 183     {
 184         return stream
 185             << '[' << color.getRed() << ", " << color.getGreen() << ", "
 186             << color.getBlue() << ']';
 187     }
 188 } // end of namespace basegfx
 189
 190 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */