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|
/*************************************************************************
** Color.cpp **
** **
** This file is part of dvisvgm -- a fast DVI to SVG converter **
** Copyright (C) 2005-2019 Martin Gieseking <martin.gieseking@uos.de> **
** **
** This program is free software; you can redistribute it and/or **
** modify it under the terms of the GNU General Public License as **
** published by the Free Software Foundation; either version 3 of **
** the License, or (at your option) any later version. **
** **
** This program is distributed in the hope that it will be useful, but **
** WITHOUT ANY WARRANTY; without even the implied warranty of **
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the **
** GNU General Public License for more details. **
** **
** You should have received a copy of the GNU General Public License **
** along with this program; if not, see <http://www.gnu.org/licenses/>. **
*************************************************************************/
#include <array>
#include <algorithm>
#include <cctype>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <iomanip>
#include <sstream>
#include "Color.hpp"
#include "utility.hpp"
using namespace std;
bool Color::SUPPRESS_COLOR_NAMES = true;
const Color Color::BLACK(uint32_t(0));
const Color Color::WHITE(uint8_t(255), uint8_t(255), uint8_t(255));
const Color Color::TRANSPARENT(uint32_t(0xff000000));
static inline uint8_t double_to_byte (double v) {
v = max(0.0, min(1.0, v));
return uint8_t(floor(255*v+0.5));
}
Color::Color (const string &psname) {
if (!setPSName(psname, false))
setGray(uint8_t(0));
}
void Color::setRGB (double r, double g, double b) {
setRGB(double_to_byte(r), double_to_byte(g), double_to_byte(b));
}
/** Expects a PostScript color name and sets the color accordingly.
* @param[in] name PS color name
* @param[in] case_sensitive if true, upper/lower case spelling is significant
* @return true if color name could be applied properly */
bool Color::setPSName (string name, bool case_sensitive) {
if (name[0] == '#') {
char *p=0;
_rgb = uint32_t(strtol(name.c_str()+1, &p, 16));
while (isspace(*p))
p++;
return (*p == 0 && _rgb <= 0xFFFFFF);
}
struct ColorConstant {
const char *name;
const uint32_t rgb;
};
// converted color constants from color.pro
static const array<ColorConstant, 68> constants {{
{"Apricot", 0xFFAD7A},
{"Aquamarine", 0x2DFFB2},
{"Bittersweet", 0xC10200},
{"Black", 0x000000},
{"Blue", 0x0000FF},
{"BlueGreen", 0x26FFAA},
{"BlueViolet", 0x190CF4},
{"BrickRed", 0xB70000},
{"Brown", 0x660000},
{"BurntOrange", 0xFF7C00},
{"CadetBlue", 0x606DC4},
{"CarnationPink", 0xFF5EFF},
{"Cerulean", 0x0FE2FF},
{"CornflowerBlue", 0x59DDFF},
{"Cyan", 0x00FFFF},
{"Dandelion", 0xFFB528},
{"DarkOrchid", 0x9932CC},
{"Emerald", 0x00FF7F},
{"ForestGreen", 0x00E000},
{"Fuchsia", 0x7202EA},
{"Goldenrod", 0xFFE528},
{"Gray", 0x7F7F7F},
{"Green", 0x00FF00},
{"GreenYellow", 0xD8FF4F},
{"JungleGreen", 0x02FF7A},
{"Lavender", 0xFF84FF},
{"LimeGreen", 0x7FFF00},
{"Magenta", 0xFF00FF},
{"Mahogany", 0xA50000},
{"Maroon", 0xAD0000},
{"Melon", 0xFF897F},
{"MidnightBlue", 0x007091},
{"Mulberry", 0xA314F9},
{"NavyBlue", 0x0F75FF},
{"OliveGreen", 0x009900},
{"Orange", 0xFF6321},
{"OrangeRed", 0xFF007F},
{"Orchid", 0xAD5BFF},
{"Peach", 0xFF7F4C},
{"Periwinkle", 0x6D72FF},
{"PineGreen", 0x00BF28},
{"Plum", 0x7F00FF},
{"ProcessBlue", 0x0AFFFF},
{"Purple", 0x8C23FF},
{"RawSienna", 0x8C0000},
{"Red", 0xFF0000},
{"RedOrange", 0xFF3A21},
{"RedViolet", 0x9600A8},
{"Rhodamine", 0xFF2DFF},
{"RoyalBlue", 0x007FFF},
{"RoyalPurple", 0x3F19FF},
{"RubineRed", 0xFF00DD},
{"Salmon", 0xFF779E},
{"SeaGreen", 0x4FFF7F},
{"Sepia", 0x4C0000},
{"SkyBlue", 0x60FFE0},
{"SpringGreen", 0xBCFF3D},
{"Tan", 0xDB9370},
{"TealBlue", 0x1EF9A3},
{"Thistle", 0xE068FF},
{"Turquoise", 0x26FFCC},
{"Violet", 0x351EFF},
{"VioletRed", 0xFF30FF},
{"White", 0xFFFFFF},
{"WildStrawberry", 0xFF0A9B},
{"Yellow", 0xFFFF00},
{"YellowGreen", 0x8EFF42},
{"YellowOrange", 0xFF9300},
}};
if (case_sensitive) {
const ColorConstant cmppair = {name.c_str(), 0};
auto it = lower_bound(constants.begin(), constants.end(), cmppair,
[](const ColorConstant &c1, const ColorConstant &c2) {
return strcmp(c1.name, c2.name) < 0;
}
);
if (it != constants.end() && it->name == name) {
_rgb = it->rgb;
return true;
}
}
else {
name = util::tolower(name);
auto it = find_if(constants.begin(), constants.end(), [&](const ColorConstant &cc) {
return name == util::tolower(cc.name);
});
if (it != constants.end()) {
_rgb = it->rgb;
return true;
}
}
return false;
}
void Color::setHSB (double h, double s, double b) {
valarray<double> hsb(3), rgb(3);
hsb[0] = h;
hsb[1] = s;
hsb[2] = b;
HSB2RGB(hsb, rgb);
setRGB(rgb);
}
void Color::setCMYK (double c, double m, double y, double k) {
valarray<double> cmyk(4), rgb(3);
cmyk[0] = c;
cmyk[1] = m;
cmyk[2] = y;
cmyk[3] = k;
CMYK2RGB(cmyk, rgb);
setRGB(rgb);
}
void Color::setCMYK (const std::valarray<double> &cmyk) {
valarray<double> rgb(3);
CMYK2RGB(cmyk, rgb);
setRGB(rgb);
}
void Color::set (ColorSpace colorSpace, VectorIterator<double> &it) {
switch (colorSpace) {
case ColorSpace::GRAY: setGray(*it++); break;
case ColorSpace::RGB : setRGB(*it, *(it+1), *(it+2)); it+=3; break;
case ColorSpace::LAB : setLab(*it, *(it+1), *(it+2)); it+=3; break;
case ColorSpace::CMYK: setCMYK(*it, *(it+1), *(it+2), *(it+3)); it+=4; break;
}
}
Color Color::operator *= (double c) {
if (abs(c) < 0.001)
_rgb &= 0xff000000;
else if (abs(c-trunc(c)) < 0.999) {
uint32_t rgb=0;
for (int i=0; i < 3; i++) {
rgb |= uint32_t((_rgb & 0xff)*c+0.5) << (8*i);
_rgb >>= 8;
}
_rgb = rgb;
}
return *this;
}
string Color::rgbString () const {
ostringstream oss;
oss << '#';
for (int i=2; i >= 0; i--) {
oss << setbase(16) << setfill('0') << setw(2)
<< (((_rgb >> (8*i)) & 0xff));
}
return oss.str();
}
/** Returns an SVG color string representing the current color. The result can
* either be an SVG color name or an RGB string of the form #RRGGBB. The latter
* will be returned if parameter rgbonly is true or if the SVG standard doesn't
* define a name for the current color. */
string Color::svgColorString (bool rgbonly) const {
if (!rgbonly) {
struct ColorName {
uint32_t rgb;
const char *name;
};
static const array<ColorName, 138> colornames {{
{0x000000, "black"},
{0x000080, "navy"},
{0x00008b, "darkblue"},
{0x0000cd, "mediumblue"},
{0x0000ff, "blue"},
{0x006400, "darkgreen"},
{0x008000, "green"},
{0x008080, "teal"},
{0x008b8b, "darkcyan"},
{0x00bfff, "deepskyblue"},
{0x00ced1, "darkturquoise"},
{0x00fa9a, "mediumspringgreen"},
{0x00ff00, "lime"},
{0x00ff7f, "springgreen"},
{0x00ffff, "cyan"},
{0x191970, "midnightblue"},
{0x1e90ff, "dodgerblue"},
{0x20b2aa, "lightseagreen"},
{0x228b22, "forestgreen"},
{0x2e8b57, "seagreen"},
{0x2f4f4f, "darkslategray"},
{0x32cd32, "limegreen"},
{0x3cb371, "mediumseagreen"},
{0x40e0d0, "turquoise"},
{0x4169e1, "royalblue"},
{0x4682b4, "steelblue"},
{0x483d8b, "darkslateblue"},
{0x48d1cc, "mediumturquoise"},
{0x4b0082, "indigo"},
{0x556b2f, "darkolivegreen"},
{0x5f9ea0, "cadetblue"},
{0x6495ed, "cornflowerblue"},
{0x66cdaa, "mediumaquamarine"},
{0x696969, "dimgray"},
{0x6a5acd, "slateblue"},
{0x6b8e23, "olivedrab"},
{0x708090, "slategray"},
{0x778899, "lightslategray"},
{0x7b68ee, "mediumslateblue"},
{0x7cfc00, "lawngreen"},
{0x7fff00, "chartreuse"},
{0x7fffd4, "aquamarine"},
{0x800000, "maroon"},
{0x800080, "purple"},
{0x808000, "olive"},
{0x808080, "gray"},
{0x87ceeb, "skyblue"},
{0x87cefa, "lightskyblue"},
{0x8a2be2, "blueviolet"},
{0x8b0000, "darkred"},
{0x8b008b, "darkmagenta"},
{0x8b4513, "saddlebrown"},
{0x8fbc8f, "darkseagreen"},
{0x90ee90, "lightgreen"},
{0x9370db, "mediumpurple"},
{0x9400d3, "darkviolet"},
{0x98fb98, "palegreen"},
{0x9932cc, "darkorchid"},
{0x9acd32, "yellowgreen"},
{0xa0522d, "sienna"},
{0xa52a2a, "brown"},
{0xa9a9a9, "darkgray"},
{0xadd8e6, "lightblue"},
{0xadff2f, "greenyellow"},
{0xafeeee, "paleturquoise"},
{0xb0c4de, "lightsteelblue"},
{0xb0e0e6, "powderblue"},
{0xb22222, "firebrick"},
{0xb8860b, "darkgoldenrod"},
{0xba55d3, "mediumorchid"},
{0xbc8f8f, "rosybrown"},
{0xbdb76b, "darkkhaki"},
{0xc0c0c0, "silver"},
{0xc71585, "mediumvioletred"},
{0xcd5c5c, "indianred"},
{0xcd853f, "peru"},
{0xd2691e, "chocolate"},
{0xd2b48c, "tan"},
{0xd3d3d3, "lightgray"},
{0xd8bfd8, "thistle"},
{0xda70d6, "orchid"},
{0xdaa520, "goldenrod"},
{0xdb7093, "palevioletred"},
{0xdc143c, "crimson"},
{0xdcdcdc, "gainsboro"},
{0xdda0dd, "plum"},
{0xdeb887, "burlywood"},
{0xe0ffff, "lightcyan"},
{0xe6e6fa, "lavender"},
{0xe9967a, "darksalmon"},
{0xee82ee, "violet"},
{0xeee8aa, "palegoldenrod"},
{0xf08080, "lightcoral"},
{0xf0e68c, "khaki"},
{0xf0f8ff, "aliceblue"},
{0xf0fff0, "honeydew"},
{0xf0ffff, "azure"},
{0xf4a460, "sandybrown"},
{0xf5deb3, "wheat"},
{0xf5f5dc, "beige"},
{0xf5f5f5, "whitesmoke"},
{0xf5fffa, "mintcream"},
{0xf8f8ff, "ghostwhite"},
{0xfa8072, "salmon"},
{0xfaebd7, "antiquewhite"},
{0xfaf0e6, "linen"},
{0xfafad2, "lightgoldenrodyellow"},
{0xfdf5e6, "oldlace"},
{0xff0000, "red"},
{0xff00ff, "magenta"},
{0xff1493, "deeppink"},
{0xff4500, "orangered"},
{0xff6347, "tomato"},
{0xff69b4, "hotpink"},
{0xff7f50, "coral"},
{0xff8c00, "darkorange"},
{0xffa07a, "lightsalmon"},
{0xffa500, "orange"},
{0xffb6c1, "lightpink"},
{0xffc0cb, "pink"},
{0xffd700, "gold"},
{0xffdab9, "peachpuff"},
{0xffdead, "navajowhite"},
{0xffe4b5, "moccasin"},
{0xffe4c4, "bisque"},
{0xffe4e1, "mistyrose"},
{0xffebcd, "blanchedalmond"},
{0xffefd5, "papayawhip"},
{0xfff0f5, "lavenderblush"},
{0xfff5ee, "seashell"},
{0xfff8dc, "cornsilk"},
{0xfffacd, "lemonchiffon"},
{0xfffaf0, "floralwhite"},
{0xfffafa, "snow"},
{0xffff00, "yellow"},
{0xffffe0, "lightyellow"},
{0xfffff0, "ivory"},
{0xffffff, "white"}
}};
ColorName cmppair = {_rgb, 0};
auto it = lower_bound(colornames.begin(), colornames.end(), cmppair, [](const ColorName &c1, const ColorName &c2) {
return c1.rgb < c2.rgb;
});
if (it != colornames.end() && it->rgb == _rgb)
return it->name;
}
return rgbString();
}
/** Approximates a CMYK color by an RGB triple. The component values
* are expected to be normalized, i.e. 0 <= cmyk[i],rgb[j] <= 1.
* @param[in] cmyk color in CMYK space
* @param[out] rgb RGB approximation */
void Color::CMYK2RGB (const valarray<double> &cmyk, valarray<double> &rgb) {
double kc = 1.0-cmyk[3];
for (int i=0; i < 3; i++)
rgb[i] = min(1.0, max(0.0, (1.0-cmyk[i])*kc));
}
void Color::RGB2CMYK (const valarray<double> &rgb, valarray<double> &cmyk) {
double c = 1-rgb[0];
double m = 1-rgb[1];
double y = 1-rgb[2];
cmyk[3] = min(min(c, m), y);
cmyk[0] = c-cmyk[3];
cmyk[1] = m-cmyk[3];
cmyk[2] = y-cmyk[3];
}
/** Converts a color given in HSB coordinates to RGB.
* @param[in] hsb color in HSB space
* @param[out] rgb color in RGB space */
void Color::HSB2RGB (const valarray<double> &hsb, valarray<double> &rgb) {
if (hsb[1] == 0)
rgb[0] = rgb[1] = rgb[2] = hsb[2];
else {
double h = hsb[0]-floor(hsb[0]);
int i = int(6*h);
double f = 6*h-i;
double p = hsb[2]*(1-hsb[1]);
double q = hsb[2]*(1-hsb[1]*f);
double t = hsb[2]*(1-hsb[1]*(1-f));
switch (i) {
case 0 : rgb[0]=hsb[2]; rgb[1]=t; rgb[2]=p; break;
case 1 : rgb[0]=q; rgb[1]=hsb[2]; rgb[2]=p; break;
case 2 : rgb[0]=p; rgb[1]=hsb[2]; rgb[2]=t; break;
case 3 : rgb[0]=p; rgb[1]=q; rgb[2]=hsb[2]; break;
case 4 : rgb[0]=t; rgb[1]=p; rgb[2]=hsb[2]; break;
case 5 : rgb[0]=hsb[2]; rgb[1]=p; rgb[2]=q; break;
default: ; // prevent compiler warning
}
}
}
double Color::getGray () const {
double r, g, b;
getRGB(r, g, b);
return r*0.3 + g*0.59 + b*0.11; // gray value according to NTSC video standard
}
void Color::getGray (valarray<double> &gray) const {
gray.resize(1);
gray[0] = getGray();
}
void Color::getRGB (double &r, double &g, double &b) const {
r = ((_rgb >> 16) & 255) / 255.0;
g = ((_rgb >> 8) & 255) / 255.0;
b = (_rgb & 255) / 255.0;
}
void Color::getRGB (valarray<double> &rgb) const {
rgb.resize(3);
double r, g, b;
getRGB(r, g, b);
rgb[0] = r;
rgb[1] = g;
rgb[2] = b;
}
void Color::getCMYK (double &c, double &m, double &y, double &k) const {
valarray<double> rgb(3), cmyk(4);
getRGB(rgb);
RGB2CMYK(rgb, cmyk);
c = cmyk[0];
m = cmyk[1];
y = cmyk[2];
k = cmyk[3];
}
void Color::getCMYK (std::valarray<double> &cmyk) const {
cmyk.resize(4);
valarray<double> rgb(3);
getRGB(rgb);
RGB2CMYK(rgb, cmyk);
}
void Color::getXYZ (double &x, double &y, double &z) const {
valarray<double> rgb(3), xyz(3);
getRGB(rgb);
RGB2XYZ(rgb, xyz);
x = xyz[0];
y = xyz[1];
z = xyz[2];
}
void Color::setXYZ (double x, double y, double z) {
valarray<double> xyz(3), rgb(3);
xyz[0] = x;
xyz[1] = y;
xyz[2] = z;
XYZ2RGB(xyz, rgb);
setRGB(rgb);
}
void Color::setXYZ (const valarray<double> &xyz) {
valarray<double> rgb(3);
XYZ2RGB(xyz, rgb);
setRGB(rgb);
}
void Color::setLab (double l, double a, double b) {
valarray<double> lab(3), xyz(3);
lab[0] = l;
lab[1] = a;
lab[2] = b;
Lab2XYZ(lab, xyz);
setXYZ(xyz);
}
void Color::setLab (const valarray<double> &lab) {
valarray<double> xyz(3);
Lab2XYZ(lab, xyz);
setXYZ(xyz);
}
/** Get the color in CIELAB color space using the sRGB working space and reference white D65. */
void Color::getLab (double &l, double &a, double &b) const {
valarray<double> rgb(3), lab(3);
getRGB(rgb);
RGB2Lab(rgb, lab);
l = lab[0];
a = lab[1];
b = lab[2];
}
void Color::getLab (std::valarray<double> &lab) const {
lab.resize(3);
valarray<double> rgb(3);
getRGB(rgb);
RGB2Lab(rgb, lab);
}
// static inline double sqr (double x) {return x*x;}
static inline double cube (double x) {return x*x*x;}
void Color::Lab2XYZ (const valarray<double> &lab, valarray<double> &xyz) {
xyz.resize(3);
double wx=0.95047, wy=1.00, wz=1.08883; // reference white D65
double eps = 0.008856;
double kappa = 903.3;
double fy = (lab[0]+16)/116;
double fx = lab[1]/500 + fy;
double fz = fy - lab[2]/200;
double xr = (cube(fx) > eps ? cube(fx) : (116*fx-16)/kappa);
double yr = (lab[0] > kappa*eps ? cube((lab[0]+16)/116) : lab[0]/kappa);
double zr = (cube(fz) > eps ? cube(fz) : (116*fz-16)/kappa);
xyz[0] = xr*wx;
xyz[1] = yr*wy;
xyz[2] = zr*wz;
}
void Color::XYZ2RGB (const valarray<double> &xyz, valarray<double> &rgb) {
rgb.resize(3);
rgb[0] = 3.2404542*xyz[0] - 1.5371385*xyz[1] - 0.4985314*xyz[2];
rgb[1] = -0.9692660*xyz[0] + 1.8760108*xyz[1] + 0.0415560*xyz[2];
rgb[2] = 0.0556434*xyz[0] - 0.2040259*xyz[1] + 1.0572252*xyz[2];
for (int i=0; i < 3; i++)
rgb[i] = (rgb[i] <= 0.0031308 ? 12.92*rgb[i] : 1.055*pow(rgb[i], 1/2.4)-0.055);
}
void Color::RGB2XYZ (valarray<double> rgb, valarray<double> &xyz) {
xyz.resize(3);
for (int i=0; i < 3; i++)
rgb[i] = (rgb[i] <= 0.04045 ? rgb[i]/12.92 : pow((rgb[i]+0.055)/1.055, 2.4));
xyz[0] = 0.4124564*rgb[0] + 0.3575761*rgb[1] + 0.1804375*rgb[2];
xyz[1] = 0.2126729*rgb[0] + 0.7151522*rgb[1] + 0.0721750*rgb[2];
xyz[2] = 0.0193339*rgb[0] + 0.1191920*rgb[1] + 0.9503041*rgb[2];
}
void Color::RGB2Lab (const valarray<double> &rgb, valarray<double> &lab) {
double wx=0.95047, wy=1.00, wz=1.08883; // reference white D65
double eps = 0.008856;
double kappa = 903.3;
valarray<double> xyz(3);
RGB2XYZ(rgb, xyz);
xyz[0] /= wx;
xyz[1] /= wy;
xyz[2] /= wz;
double fx = (xyz[0] > eps ? pow(xyz[0], 1.0/3) : (kappa*xyz[0]+16)/116);
double fy = (xyz[1] > eps ? pow(xyz[1], 1.0/3) : (kappa*xyz[1]+16)/116);
double fz = (xyz[2] > eps ? pow(xyz[2], 1.0/3) : (kappa*xyz[2]+16)/116);
lab[0] = 116*fy-16;
lab[1] = 500*(fx-fy);
lab[2] = 200*(fy-fz);
}
#if 0
/** Returns the Delta E difference (CIE 2000) between this and another color. */
double Color::deltaE (const Color &c) const {
double l1, a1, b1;
double l2, a2, b2;
getLab(l1, a1, b1);
c.getLab(l2, a2, b2);
const double deltaL = l2-l1;
const double lBar = (l1+l2)/2;
const double c1 = sqrt(a1*a1 + b1*b1);
const double c2 = sqrt(a2*a2 + b2*b2);
const double cBar = (c1+c2)/2.0;
const double g = (1.0-sqrt(pow(cBar, 7.0)/(pow(cBar, 7.0)+6103515625.0)))/2.0;
const double aa1 = a1*(1.0+g);
const double aa2 = a2*(1.0+g);
const double cc1 = sqrt(aa1*aa1 + b1*b1);
const double cc2 = sqrt(aa2*aa2 + b2*b2);
const double ccBar = (cc1+cc2)/2.0;
const double deltaCC = cc2-cc1;
double hh1 = atan2(b1, aa1);
if (hh1 < 0) hh1 += deg2rad(360);
double hh2 = atan2(b2, aa2);
if (hh2 < 0) hh2 += deg2rad(360);
const double hhBar = (std::abs(hh1-hh2) > deg2rad(180) ? (hh1+hh2+deg2rad(360)) : (hh1+hh2))/2.0;
const double t = 1.0
- 0.17*cos(hhBar-deg2rad(30.0))
+ 0.24*cos(2.0*hhBar)
+ 0.32*cos(3.0*hhBar+deg2rad(6.0))
- 0.20*cos(4.0*hhBar-deg2rad(63.0));
double deltaHH = hh2-hh1;
if (deltaHH < deg2rad(-180))
deltaHH += deg2rad(360);
else if (deltaHH > deg2rad(180))
deltaHH -= deg2rad(360);
const double deltaHHH = 2.0*sqrt(cc1*cc2)*sin(deltaHH/2.0);
const double sl = 1.0 + 0.015*sqr(lBar-50.0)/sqrt(20.0+sqr(lBar-50.0));
const double sc = 1.0 + 0.045*ccBar;
const double sh = 1.0 + 0.015*ccBar*t;
const double deltaTheta = deg2rad(30)*exp(-sqr((hhBar-deg2rad(275))/deg2rad(25)));
const double rc = 2.0*sqrt(pow(ccBar, 7)/(pow(ccBar, 7)+6103515625.0));
const double rt = -rc*sin(2.0*deltaTheta);
const double deltaE = sqrt(sqr(deltaL/sl) + sqr(deltaCC/sc) + sqr(deltaHHH/sh) + rt*deltaCC/sc*deltaHHH/sh);
return deltaE;
}
#endif
int Color::numComponents (ColorSpace colorSpace) {
switch (colorSpace) {
case ColorSpace::GRAY: return 1;
case ColorSpace::LAB:
case ColorSpace::RGB: return 3;
case ColorSpace::CMYK: return 4;
}
return 0;
}
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