// io-hub - Modular Input/Output. {{{ // // Copyright (C) 2013 Maxime Hadjinlian // // APBTeam: // Web: http://apbteam.org/ // Email: team AT apbteam DOT org // // This program is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 2 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. // // }}} #include "rgb.hh" int Rgb::rgb_to_hue (int r, int g, int b) { uint8_t min = 255, max = 0, hue; // find minimal between r, g and b if (r < min) min = r; if (g < min) min = g; if (b < min) min = b; // find maximal between r, g and b if (r > max) max = r; if (g > max) max = g; if (b > max) max = b; if (min == max) return 0; /* Compute hue */ if (max == r) hue = 0 + 43 * (g - b) / (max - min); else if (max == g) hue = 85 + 43 * (b - r) / (max - min); else /* max == b */ hue = 171 + 43 * (r - g) / (max - min); return hue; }