00001 #include "Color.h"
00002
00003 Color::Color(float r, float g, float b, float a):m_red(r),m_green(g),m_blue(b),m_alpha(a) { }
00004
00005 HSLColor::HSLColor(float h, float s, float l, float a):m_hue(h),m_saturation(s),m_lightness(l),m_alpha(a) { }
00006
00007 Color HSLColor::toColor() const{
00008 return HSL2RGB(*this);
00009 }
00010
00011 void HSLColor::fromColor(const Color& color){
00012 *this = RGB2HSL(color);
00013 }
00014
00015 HSLColor RGB2HSL(const Color& color){
00016 float min, max, hue, saturation, lightness, alpha;
00017
00018 min = (color.red() < color.green()) ? color.red() : color.green();
00019 min = (min < color.blue()) ? min : color.blue();
00020
00021 max = (color.red() > color.green()) ? color.red() : color.green();
00022 max = (max > color.blue()) ? max : color.blue();
00023
00024 lightness = 0.5*(min + max);
00025
00026 if(max == min){
00027 hue = 0.f;
00028 saturation = 0.f;
00029 } else {
00030 saturation = lightness < 0.5 ? (max - min)/(max + min) : (max - min)/(2.f - max - min);
00031
00032 if(max == color.red()) {
00033 hue = (color.green() - color.blue())/(max - min);
00034 } else if(max == color.green()){
00035 hue = 2.f + (color.blue() - color.red())/(max - min);
00036 } else {
00037 hue = 4.f + (color.red() - color.green())/(max - min);
00038 }
00039 hue = hue < 0 ? hue + 6.f : hue;
00040 }
00041
00042 alpha = color.alpha();
00043 return HSLColor(hue, saturation, lightness, alpha);
00044 }
00045
00046 Color HSL2RGB(const HSLColor& color) {
00047 float q, p, h, tc[3], col[3];
00048 q = color.lightness() < 0.5 ? color.lightness() * (1.f + color.saturation()) : color.lightness() + color.saturation() - color.lightness() * color.saturation();
00049 p = 2 * color.lightness() - q;
00050 h = color.hue() / 6.f;
00051
00052 tc[0] = h + 1.f/3.f;
00053 tc[1] = h;
00054 tc[2] = h - 1.f/3.f;
00055
00056 for(unsigned int i = 0; i < 3; i++){
00057 tc[i] = tc[i] < 0 ? tc[i] + 1.f: tc[i];
00058 tc[i] = tc[i] > 1 ? tc[i] - 1.f: tc[i];
00059 if(6.f * tc[i] < 1.f){
00060 col[i] = p + ((q - p) * 6.f * tc[i]);
00061 } else if(2.f * tc[i] < 1.f){
00062 col[i] = q;
00063 } else if(3.f * tc[i] < 2.f){
00064 col[i] = p + ((q - p) * 6.f * (2.f/3.f - tc[i]));
00065 } else {
00066 col[i] = p;
00067 }
00068 }
00069
00070 return Color(col[0], col[1], col[2], color.alpha());
00071 }
00072
00073 std::ostream & operator<< (std::ostream& out, const Color& color){
00074 out << "RGB(" << color.red() << ", " << color.green() << ", " << color.blue() << ")";
00075 return out;
00076 }
00077
00078 std::ostream & operator<< (std::ostream& out, const HSLColor& color){
00079 out << "HSL(" << color.hue() << ", " << color.saturation() << ", " << color.lightness() << ")";
00080 return out;
00081 }
