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