ref: 599ce757a1f644aba35d692cec68202944f7163f
dir: /src/gfx/pal_sorting.cpp/
/* * This file is part of RGBDS. * * Copyright (c) 2022, Eldred Habert and RGBDS contributors. * * SPDX-License-Identifier: MIT */ #include "gfx/pal_sorting.hpp" #include <algorithm> #include <png.h> #include <vector> #include "helpers.h" #include "gfx/main.hpp" #include "gfx/process.hpp" namespace sorting { void indexed(std::vector<Palette> &palettes, int palSize, png_color const *palRGB, png_byte *palAlpha) { options.verbosePrint(Options::VERB_LOG_ACT, "Sorting palettes using embedded palette...\n"); auto pngToRgb = [&palRGB, &palAlpha](int index) { auto const &c = palRGB[index]; return Rgba(c.red, c.green, c.blue, palAlpha ? palAlpha[index] : 0xFF); }; for (Palette &pal : palettes) { std::sort(pal.begin(), pal.end(), [&](uint16_t lhs, uint16_t rhs) { // Iterate through the PNG's palette, looking for either of the two for (int i = 0; i < palSize; ++i) { uint16_t color = pngToRgb(i).cgbColor(); if (color == Rgba::transparent) { continue; } // Return whether lhs < rhs if (color == rhs) { return false; } if (color == lhs) { return true; } } unreachable_(); // This should not be possible }); } } void grayscale(std::vector<Palette> &palettes, std::array<std::optional<Rgba>, 0x8001> const &colors) { options.verbosePrint(Options::VERB_LOG_ACT, "Sorting grayscale-only palette...\n"); // This method is only applicable if there are at most as many colors as colors per palette, so // we should only have a single palette. assert(palettes.size() == 1); Palette &palette = palettes[0]; std::fill(palette.colors.begin(), palette.colors.end(), Rgba::transparent); for (auto const &slot : colors) { if (!slot.has_value() || slot->isTransparent()) { continue; } palette[slot->grayIndex()] = slot->cgbColor(); } } static unsigned int legacyLuminance(uint16_t color) { uint8_t red = color & 0b11111; uint8_t green = color >> 5 & 0b11111; uint8_t blue = color >> 10; return 2126 * red + 7152 * green + 722 * blue; } void rgb(std::vector<Palette> &palettes) { options.verbosePrint(Options::VERB_LOG_ACT, "Sorting palettes by \"\"\"luminance\"\"\"...\n"); for (Palette &pal : palettes) { std::sort(pal.begin(), pal.end(), [](uint16_t lhs, uint16_t rhs) { return legacyLuminance(lhs) > legacyLuminance(rhs); }); } } } // namespace sorting