color: Add color

include/hyprgraphics/color/Color.hpp

@@ -0,0 +1,38 @@
+#pragma once
+
+namespace Hyprgraphics {
+    class CColor {
+      public:
+        // SRGB (NOT linear!!) 0.0 - 1.0
+        struct SSRGB {
+            double r = 0, g = 0, b = 0;
+        };
+
+        // HSL 0.0 - 1.0
+        struct SHSL {
+            double h = 0, s = 0, l = 0;
+        };
+
+        // OkLab 0.0 - 1.0
+        struct SOkLab {
+            double l = 0, a = 0, b = 0;
+        };
+
+        CColor(); // black
+        CColor(const SSRGB& rgb);
+        CColor(const SHSL& hsl);
+        CColor(const SOkLab& lab);
+
+        SSRGB  asRgb() const;
+        SHSL   asHSL() const;
+        SOkLab asOkLab() const;
+
+        bool operator==(const CColor& other) const {
+            return other.r == r && other.g == g && other.b == b;
+        }
+
+      private:
+        // SRGB space for internal color storage
+        double r = 0, g = 0, b = 0;
+    };
+};

src/color/Color.cpp

@@ -0,0 +1,115 @@
+#include <hyprgraphics/color/Color.hpp>
+#include <cmath>
+
+using namespace Hyprgraphics;
+
+static double gammaToLinear(const double in) {
+    return in >= 0.04045 ? std::pow((in + 0.055) / 1.055, 2.4) : in / 12.92;
+}
+
+static double linearToGamma(const double in) {
+    return in >= 0.0031308 ? 1.055 * std::pow(in, 0.41666666666) - 0.055 : 12.92 * in;
+}
+
+static double hueToRgb(double p, double q, double t) {
+    if (t < 0)
+        t += 1;
+    if (t > 1)
+        t -= 1;
+    if (t < 1.0 / 6.0)
+        return p + (q - p) * 6.0 * t;
+    if (t < 1.0 / 2.0)
+        return q;
+    if (t < 2.0 / 3.0)
+        return p + (q - p) * (2.0 / 3.0 - t) * 6.0;
+    return p;
+}
+
+Hyprgraphics::CColor::CColor() {
+    ;
+}
+
+Hyprgraphics::CColor::CColor(const SSRGB& rgb) {
+    r = rgb.r;
+    g = rgb.g;
+    b = rgb.b;
+}
+
+Hyprgraphics::CColor::CColor(const SHSL& hsl) {
+    if (hsl.s <= 0) {
+        r = hsl.l;
+        g = hsl.l;
+        b = hsl.l;
+    } else {
+        const double q = hsl.l < 0.5 ? hsl.l * (1.0 + hsl.s) : hsl.l + hsl.s - hsl.l * hsl.s;
+        const double p = 2.0 * hsl.l - q;
+        r              = hueToRgb(p, q, hsl.h + 1.0 / 3.0);
+        g              = hueToRgb(p, q, hsl.h);
+        b              = hueToRgb(p, q, hsl.h - 1.0 / 3.0);
+    }
+}
+
+Hyprgraphics::CColor::CColor(const SOkLab& lab) {
+    const double l = std::pow(lab.l + lab.a * 0.3963377774 + lab.b * 0.2158037573, 3);
+    const double m = std::pow(lab.l + lab.a * (-0.1055613458) + lab.b * (-0.0638541728), 3);
+    const double s = std::pow(lab.l + lab.a * (-0.0894841775) + lab.b * (-1.2914855480), 3);
+
+    r = linearToGamma(l * 4.0767416621 + m * -3.3077115913 + s * 0.2309699292);
+    g = linearToGamma(l * (-1.2684380046) + m * 2.6097574011 + s * (-0.3413193965));
+    b = linearToGamma(l * (-0.0041960863) + m * (-0.7034186147) + s * 1.7076147010);
+}
+
+Hyprgraphics::CColor::SSRGB Hyprgraphics::CColor::asRgb() const {
+    return Hyprgraphics::CColor::SSRGB{
+        .r = r,
+        .g = g,
+        .b = b,
+    };
+}
+
+Hyprgraphics::CColor::SHSL Hyprgraphics::CColor::asHSL() const {
+    const double vmax = std::max(std::max(r, g), b), vmin = std::min(std::min(r, g), b);
+    double       h = 0, s = 0, l = (vmax + vmin) / 2.0;
+
+    if (vmax == vmin) {
+        return Hyprgraphics::CColor::SHSL{
+            .h = 0,
+            .s = 0,
+            .l = l,
+        };
+    }
+
+    const double d = vmax - vmin;
+    s              = l > 0.5 ? d / (2.0 - vmax - vmin) : d / (vmax + vmin);
+
+    if (vmax == r)
+        h = (g - b) / d + (g < b ? 6.0 : 0.0);
+    if (vmax == g)
+        h = (b - r) / d + 2;
+    if (vmax == b)
+        h = (r - g) / d + 4;
+
+    h /= 6.0;
+
+    return Hyprgraphics::CColor::SHSL{
+        .h = h,
+        .s = s,
+        .l = l,
+    };
+}
+
+Hyprgraphics::CColor::SOkLab Hyprgraphics::CColor::asOkLab() const {
+    const double linR = gammaToLinear(r);
+    const double linG = gammaToLinear(g);
+    const double linB = gammaToLinear(b);
+
+    const double l = std::cbrtf(0.4122214708 * linR + 0.5363325363 * linG + 0.0514459929 * linB);
+    const double m = std::cbrtf(0.2119034982 * linR + 0.6806995451 * linG + 0.1073969566 * linB);
+    const double s = std::cbrtf(0.0883024619 * linR + 0.2817188376 * linG + 0.6299787005 * linB);
+
+    return Hyprgraphics::CColor::SOkLab{
+        .l = l * 0.2104542553 + m * 0.7936177850 + s * (-0.0040720468),
+        .a = l * 1.9779984951 + m * (-2.4285922050) + s * 0.4505937099,
+        .b = l * 0.0259040371 + m * 0.7827717662 + s * (-0.8086757660),
+    };
+}