tools/source/generic/color.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <sal/config.h>
  21
  22 #include <algorithm>
  23 #include <iomanip>
  24 #include <sstream>
  25 #include <stdlib.h>
  26
  27 #include <tools/color.hxx>
  28 #include <tools/helpers.hxx>
  29 #include <tools/long.hxx>
  30 #include <basegfx/color/bcolortools.hxx>
  31
  32 void Color::IncreaseLuminance(sal_uInt8 cLumInc)
  33 {
  34     R = sal_uInt8(std::clamp(R + cLumInc, 0, 255));
  35     G = sal_uInt8(std::clamp(G + cLumInc, 0, 255));
  36     B = sal_uInt8(std::clamp(B + cLumInc, 0, 255));
  37 }
  38
  39 void Color::DecreaseLuminance(sal_uInt8 cLumDec)
  40 {
  41     R = sal_uInt8(std::clamp(R - cLumDec, 0, 255));
  42     G = sal_uInt8(std::clamp(G - cLumDec, 0, 255));
  43     B = sal_uInt8(std::clamp(B - cLumDec, 0, 255));
  44 }
  45
  46 void Color::DecreaseContrast(sal_uInt8 nContDec)
  47 {
  48     if (nContDec)
  49     {
  50         const double fM = (128.0 - 0.4985 * nContDec) / 128.0;
  51         const double fOff = 128.0 - fM * 128.0;
  52
  53         R = sal_uInt8(std::clamp(FRound(R * fM + fOff), tools::Long(0), tools::Long(255)));
  54         G = sal_uInt8(std::clamp(FRound(G * fM + fOff), tools::Long(0), tools::Long(255)));
  55         B = sal_uInt8(std::clamp(FRound(B * fM + fOff), tools::Long(0), tools::Long(255)));
  56     }
  57 }
  58
  59 // color space conversion
  60
  61 void Color::RGBtoHSB( sal_uInt16& nHue, sal_uInt16& nSat, sal_uInt16& nBri ) const
  62 {
  63     sal_uInt8 c[3];
  64     sal_uInt8 cMax, cMin;
  65
  66     c[0] = R;
  67     c[1] = G;
  68     c[2] = B;
  69
  70     cMax = c[0];
  71     if( c[1] > cMax )
  72         cMax = c[1];
  73     if( c[2] > cMax )
  74         cMax = c[2];
  75
  76     // Brightness = max(R, G, B);
  77     nBri = cMax * 100 / 255;
  78
  79     cMin = c[0];
  80     if( c[1] < cMin )
  81         cMin = c[1];
  82     if( c[2] < cMin )
  83         cMin = c[2];
  84
  85     sal_uInt8 cDelta = cMax - cMin;
  86
  87     // Saturation = max - min / max
  88     if( nBri > 0 )
  89         nSat = cDelta * 100 / cMax;
  90     else
  91         nSat = 0;
  92
  93     if( nSat == 0 )
  94         nHue = 0; // Default = undefined
  95     else
  96     {
  97         double dHue = 0.0;
  98
  99         if( c[0] == cMax )
 100         {
 101             dHue = static_cast<double>( c[1] - c[2] ) / static_cast<double>(cDelta);
 102         }
 103         else if( c[1] == cMax )
 104         {
 105             dHue = 2.0 + static_cast<double>( c[2] - c[0] ) / static_cast<double>(cDelta);
 106         }
 107         else if ( c[2] == cMax )
 108         {
 109             dHue = 4.0 + static_cast<double>( c[0] - c[1] ) / static_cast<double>(cDelta);
 110         }
 111         dHue *= 60.0;
 112
 113         if( dHue < 0.0 )
 114             dHue += 360.0;
 115
 116         nHue = static_cast<sal_uInt16>(dHue);
 117     }
 118 }
 119
 120 Color Color::HSBtoRGB( sal_uInt16 nHue, sal_uInt16 nSat, sal_uInt16 nBri )
 121 {
 122     sal_uInt8 cR=0,cG=0,cB=0;
 123     sal_uInt8 nB = static_cast<sal_uInt8>( nBri * 255 / 100 );
 124
 125     if( nSat == 0 )
 126     {
 127         cR = nB;
 128         cG = nB;
 129         cB = nB;
 130     }
 131     else
 132     {
 133         double dH = nHue;
 134         double f;
 135         sal_uInt16 n;
 136         if( dH == 360.0 )
 137             dH = 0.0;
 138
 139         dH /= 60.0;
 140         n = static_cast<sal_uInt16>(dH);
 141         f = dH - n;
 142
 143         sal_uInt8 a = static_cast<sal_uInt8>( nB * ( 100 - nSat ) / 100 );
 144         sal_uInt8 b = static_cast<sal_uInt8>( nB * ( 100 - ( static_cast<double>(nSat) * f ) ) / 100 );
 145         sal_uInt8 c = static_cast<sal_uInt8>( nB * ( 100 - ( static_cast<double>(nSat) * ( 1.0 - f ) ) ) / 100 );
 146
 147         switch( n )
 148         {
 149             case 0: cR = nB;    cG = c;     cB = a;     break;
 150             case 1: cR = b;     cG = nB;    cB = a;     break;
 151             case 2: cR = a;     cG = nB;    cB = c;     break;
 152             case 3: cR = a;     cG = b;     cB = nB;    break;
 153             case 4: cR = c;     cG = a;     cB = nB;    break;
 154             case 5: cR = nB;    cG = a;     cB = b;     break;
 155         }
 156     }
 157
 158     return Color( cR, cG, cB );
 159 }
 160
 161 Color Color::STRtoRGB(const OUString& colorname)
 162 {
 163     Color col;
 164     if(colorname.isEmpty()) return col;
 165
 166     switch(colorname.getLength()){
 167         case 7:
 168             col.mValue = colorname.copy(1,6).toUInt32(16);
 169             break;
 170         case 6:
 171             col.mValue = colorname.toUInt32(16);
 172             break;
 173         case 4:
 174         {
 175             sal_Unicode data[6] = { colorname[1], colorname[1], colorname[2],
 176                                      colorname[2], colorname[3], colorname[3] };
 177             col.mValue = OUString(data,6).toUInt32(16);
 178             break;
 179         }
 180         case 3:
 181         {
 182             sal_Unicode data[6] = { colorname[0], colorname[0], colorname[1],
 183                                      colorname[1], colorname[2], colorname[2] };
 184             col.mValue = OUString(data,6).toUInt32(16);
 185             break;
 186         }
 187         default:
 188             break;
 189     }
 190     return col;
 191 }
 192
 193 OUString Color::AsRGBHexString() const
 194 {
 195     std::stringstream ss;
 196     ss << std::hex << std::setfill ('0') << std::setw(6) << sal_uInt32(GetRGBColor());
 197     return OUString::createFromAscii(ss.str().c_str());
 198 }
 199
 200 OUString Color::AsRGBHEXString() const
 201 {
 202     std::stringstream ss;
 203     ss << std::hex << std::uppercase << std::setfill ('0') << std::setw(6) << sal_uInt32(GetRGBColor());
 204     return OUString::createFromAscii(ss.str().c_str());
 205 }
 206
 207 void Color::ApplyTintOrShade(sal_Int16 n100thPercent)
 208 {
 209     if (n100thPercent == 0)
 210         return;
 211
 212     basegfx::BColor aBColor = basegfx::utils::rgb2hsl(getBColor());
 213     double fFactor = 1.0 - (std::abs(double(n100thPercent)) / 10000.0);
 214     double fResult;
 215
 216     if (n100thPercent > 0) // tint
 217     {
 218         fResult = aBColor.getBlue() * fFactor + (1.0 - fFactor);
 219     }
 220     else // shade
 221     {
 222         fResult = aBColor.getBlue() * fFactor;
 223     }
 224
 225     aBColor.setBlue(fResult);
 226     aBColor = basegfx::utils::hsl2rgb(aBColor);
 227
 228     R = sal_uInt8(std::lround(aBColor.getRed()   * 255.0));
 229     G = sal_uInt8(std::lround(aBColor.getGreen() * 255.0));
 230     B = sal_uInt8(std::lround(aBColor.getBlue()  * 255.0));
 231 }
 232
 233 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */