include/basegfx/color/bcolor.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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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     public:
  43         /** Create a Color with red, green and blue components from [0.0 to 1.0]
  44
  45             The color is initialized to (0.0, 0.0, 0.0)
  46         */
  47         BColor()
  48         :   B3DTuple()
  49         {}
  50
  51         /** Create a 3D Color
  52
  53             @param fRed
  54             @param fGreen
  55             @param fBlue
  56             These parameters are used to initialize the red, green and blue intensities of the color
  57         */
  58         BColor(double fRed, double fGreen, double fBlue)
  59         :   B3DTuple(fRed, fGreen, fBlue)
  60         {}
  61
  62         /** Create a 3D Color
  63
  64             @param fLuminosity
  65             The parameter is used to initialize the red, green and blue intensities of the color
  66         */
  67         explicit BColor(double fLuminosity)
  68         :   B3DTuple(fLuminosity, fLuminosity, fLuminosity)
  69         {}
  70
  71         /** constructor with tuple to allow copy-constructing
  72             from B3DTuple-based classes
  73         */
  74         BColor(const ::basegfx::B3DTuple& rTuple)
  75         :   B3DTuple(rTuple)
  76         {}
  77
  78         // data access read
  79         double getRed() const { return mfX; }
  80         double getGreen() const { return mfY; }
  81         double getBlue() const { return mfZ; }
  82
  83         // data access write
  84         void setRed(double fNew) { mfX = fNew; }
  85         void setGreen(double fNew) { mfY = fNew; }
  86         void setBlue(double fNew) { mfZ = fNew; }
  87
  88         /** *=operator to allow usage from BColor, too
  89         */
  90         BColor& operator*=( const BColor& rPnt )
  91         {
  92             mfX *= rPnt.mfX;
  93             mfY *= rPnt.mfY;
  94             mfZ *= rPnt.mfZ;
  95             return *this;
  96         }
  97
  98         /** *=operator to allow usage from BColor, too
  99         */
 100         BColor& operator*=(double t)
 101         {
 102             mfX *= t;
 103             mfY *= t;
 104             mfZ *= t;
 105             return *this;
 106         }
 107
 108         /** assignment operator to allow assigning the results
 109             of B3DTuple calculations
 110         */
 111         BColor& operator=( const ::basegfx::B3DTuple& rVec )
 112         {
 113             mfX = rVec.getX();
 114             mfY = rVec.getY();
 115             mfZ = rVec.getZ();
 116             return *this;
 117         }
 118
 119         // luminance
 120         double luminance() const
 121         {
 122             const double fRedWeight(77.0 / 256.0);      // 0.30
 123             const double fGreenWeight(151.0 / 256.0);   // 0.59
 124             const double fBlueWeight(28.0 / 256.0);     // 0.11
 125
 126             return (mfX * fRedWeight + mfY * fGreenWeight + mfZ * fBlueWeight);
 127         }
 128
 129         // distances in color space
 130         double getDistanceRed(const BColor& rColor) const { return (getRed() > rColor.getRed() ? getRed() - rColor.getRed() : rColor.getRed() - getRed()); }
 131         double getDistanceGreen(const BColor& rColor) const { return (getGreen() > rColor.getGreen() ? getGreen() - rColor.getGreen() : rColor.getGreen() - getGreen()); }
 132         double getDistanceBlue(const BColor& rColor) const { return (getBlue() > rColor.getBlue() ? getBlue() - rColor.getBlue() : rColor.getBlue() - getBlue()); }
 133
 134         double getDistance(const BColor& rColor) const
 135         {
 136             const double fDistR(getDistanceRed(rColor));
 137             const double fDistG(getDistanceGreen(rColor));
 138             const double fDistB(getDistanceBlue(rColor));
 139
 140             return sqrt(fDistR * fDistR + fDistG * fDistG + fDistB * fDistB);
 141         }
 142
 143         double getMaximumDistance(const BColor& rColor) const
 144         {
 145             const double fDistR(getDistanceRed(rColor));
 146             const double fDistG(getDistanceGreen(rColor));
 147             const double fDistB(getDistanceBlue(rColor));
 148
 149             double fRetval(std::max(fDistR, fDistG));
 150             return std::max(fRetval, fDistB);
 151         }
 152
 153         // clamp color to [0.0..1.0] values in all three intensity components
 154         BColor& clamp()
 155         {
 156             mfX = std::clamp(mfX, 0.0, 1.0);
 157             mfY = std::clamp(mfY, 0.0, 1.0);
 158             mfZ = std::clamp(mfZ, 0.0, 1.0);
 159             return *this;
 160         }
 161
 162         void invert()
 163         {
 164             mfX = 1.0 - mfX;
 165             mfY = 1.0 - mfY;
 166             mfZ = 1.0 - mfZ;
 167         }
 168
 169         static const BColor& getEmptyBColor()
 170         {
 171             return static_cast<const BColor&>( ::basegfx::B3DTuple::getEmptyTuple() );
 172         }
 173
 174     };
 175
 176     template<typename charT, typename traits>
 177     std::basic_ostream<charT, traits> & operator <<(
 178         std::basic_ostream<charT, traits> & stream, BColor const & color)
 179     {
 180         return stream
 181             << '[' << color.getRed() << ", " << color.getGreen() << ", "
 182             << color.getBlue() << ']';
 183     }
 184 } // end of namespace basegfx
 185
 186 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */