feat: added phong and basic shaders, updated mesh format

src/gfx/Color.cpp

@@ -0,0 +1,46 @@
+#include <cstdint>
+#include <glm/ext/vector_float3.hpp>
+#include <string>
+#include <math.h>
+#include <iostream>
+#include "Color.h"
+
+auto hue_to_rgb(float p, float q, float t) -> float {
+    if (t < 0) {
+        t += 1;
+    } else if (t > 1) {
+        t -= 1;
+    }
+    if (t < 1.0f / 6) return p + (q - p) * 6 * t;
+    if (t < 1.0f / 2) return q;
+    if (t < 2.0f / 3) return p + (q - p) * (2.0f / 3 - t) * 6;
+    return p;
+};
+
+auto hsl_to_hex(float h, float s, float l) -> glm::vec3 {
+    h /= 360;
+    s /= 100;
+    l /= 100;
+    float r, g, b;
+    if (s == 0) {
+        r = g = b = l;
+    } else {
+        auto q = l < 0.5f ? l * (1 + s) : l + s - l * s;
+        auto p = 2 * l - q;
+        r = hue_to_rgb(p, q, h + 1.0f / 3);
+        g = hue_to_rgb(p, q, h);
+        b = hue_to_rgb(p, q, h - 1.0f / 3);
+    }
+    return glm::vec3(r, g, b);
+}
+
+auto Color::color_from_index(int index) -> glm::vec3 {
+    auto color_wheel_cycle = floorf(index / 6.0f);
+    auto darkness_cycle = floorf(index / 12.0f);
+    auto spacing = (360.0f / 6.0f);
+    auto offset = color_wheel_cycle == 0 ? 0 : spacing / (color_wheel_cycle + 2);
+    auto hue = spacing * (index % 6) + offset;
+    auto saturation = 100.0f;
+    auto lightness = 1.0f / (2 + darkness_cycle) * 100;
+    return hsl_to_hex(hue, saturation, lightness);
+}