hsl_colour hsl_colour::from_rgb(const colour& aColour)
{
double hue, saturation, lightness;
double r = aColour.red() / 255.0, g = aColour.green() / 255.0, b = aColour.blue() / 255.0;
double M = std::max(std::max(r, g), b);
double m = std::min(std::min(r, g), b);
double c = M - m;
double h2;
if (c == 0.0)
h2 = undefined_hue();
else if (M == r)
h2 = std::fmod((g - b) / c, 6.0);
else if (M == g)
h2 = (b - r) / c + 2.0;
else if (M == b)
h2 = (r - g) / c + 4.0;
else
h2 = undefined_hue();
if (h2 != undefined_hue())
{
hue = 60.0 * h2;
if (hue < 0.0)
hue += 360.0;
}
else
hue = undefined_hue();
lightness = 0.5f * (M + m);
lightness = std::max(std::min(lightness, 1.0), 0.0);
if (c == 0.0)
saturation = 0.0;
else
saturation = c / (1.0 - std::abs(2.0 * lightness - 1.0));
saturation = std::max(std::min(saturation, 1.0), 0.0);
return hsl_colour(hue, saturation, lightness);
}
hsv_colour hsv_colour::from_rgb(const colour& aColour)
{
double hue, saturation, value;
double r = aColour.red() / 255.0, g = aColour.green() / 255.0, b = aColour.blue() / 255.0;
double M = std::max(std::max(r, g), b);
double m = std::min(std::min(r, g), b);
double c = M - m;
double h2;
if (c == 0.0)
h2 = undefined_hue();
else if (M == r)
h2 = std::fmod((g - b) / c, 6.0);
else if (M == g)
h2 = (b - r) / c + 2.0;
else if (M == b)
h2 = (r - g) / c + 4.0;
else
h2 = undefined_hue();
if (h2 != undefined_hue())
{
hue = 60.0 * h2;
if (hue < 0.0)
hue += 360.0;
}
else
hue = undefined_hue();
value = M;
value = std::max(std::min(value, 1.0), 0.0);
if (c == 0.0)
saturation = 0.0;
else
saturation = c / value;
saturation = std::max(std::min(saturation, 1.0), 0.0);
return hsv_colour(hue, saturation, value, aColour.alpha() / 255.0);
}
static void SetColour ( const colour& col )
{
if (sizeof(col) == sizeof(float) * 4)
{
glColor4fv((const GLfloat*)&col);
}
else
{
glColor4f(col.red(), col.green(), col.blue(), col.alpha());
}
}
