Форум создателей искусственных интеллектов

#include <cstdint> #include <algorithm> #include <cmath> #include <initializer_list> // Colors are given as 0xRRGGBB in sRGB space. std::uint32_t AdaptDayColorToBackground(std::uint32_t dayColor, std::uint32_t backgroundColor) { // Extract normalized channels [0..1] from 0xRRGGBB auto extractChannel = [](std::uint32_t c, int shift) -> double { return static_cast<double>((c >> shift) & 0xFFu) / 255.0; }; double dr = extractChannel(dayColor, 16); double dg = extractChannel(dayColor, 8); double db = extractChannel(dayColor, 0); double br = extractChannel(backgroundColor, 16); double bg = extractChannel(backgroundColor, 8); double bb = extractChannel(backgroundColor, 0); // Compute background luminance in [0,1] (Rec.709) double bgLum = 0.2126 * br + 0.7152 * bg + 0.0722 * bb; // Target luminance for text: dark on light bg, light on dark bg. // You can tweak 0.2 / 0.8 if you want stronger/weaker contrast. double targetLum = (bgLum > 0.5) ? 0.2 : 0.8; // Normalize day color to preserve hue (base tone). double sum = dr + dg + db; if (sum <= 0.0) { // Fallback: if day color is black, use pure red as base tone. dr = 1.0; dg = 0.0; db = 0.0; sum = 1.0; } double hr = dr / sum; double hg = dg / sum; double hb = db / sum; // Luminance of normalized hue double hueLum = 0.2126 * hr + 0.7152 * hg + 0.0722 * hb; if (hueLum <= 0.0) { // Degenerate case: fallback to red hue hr = 1.0; hg = 0.0; hb = 0.0; hueLum = 0.2126; } // Scale factor to reach target luminance: Y = scale * hueLum double scale = targetLum / hueLum; // Do not exceed 1.0 in any channel (keep channels in [0,1]) double hMax = std::max({ hr, hg, hb }); if (hMax <= 0.0) { hMax = 1.0; } double scaleMax = 1.0 / hMax; if (scale < 0.0) scale = 0.0; if (scale > scaleMax) scale = scaleMax; double rr = hr * scale; double gg = hg * scale; double bb2 = hb * scale; // Clamp channels to [0,1] rr = std::max(0.0, std::min(1.0, rr)); gg = std::max(0.0, std::min(1.0, gg)); bb2 = std::max(0.0, std::min(1.0, bb2)); auto toByte = [](double v) -> std::uint32_t { double x = std::round(v * 255.0); if (x < 0.0) x = 0.0; if (x > 255.0) x = 255.0; return static_cast<std::uint32_t>(x); }; std::uint32_t R = toByte(rr); std::uint32_t G = toByte(gg); std::uint32_t B = toByte(bb2); return (R << 16) | (G << 8) | B; }