/** * Copyright © 2016 Mattias Andrée * * 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 3 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, see . */ /** * The highest colour temperature in the table. */ #define HIGHEST_TEMPERATURE 40000 /** * The lowest colour temperature in the table. */ #define LOWEST_TEMPERATURE 1000 /** * The temperature difference between the colours in the table. */ #define DELTA_TEMPERATURE 100 /** * Convert from CIE xyY to [0, 1] sRGB. * * @param x The 'x' component. * @param y The 'y' component. * @param Y The 'Y' component. * @param r Output parameter for the “red” value. * (Seriously, sRGB red is orange, just look at it fullscreen.) * @param g Output parameter for the green value. * @param b Output parameter for the blue value. */ void ciexyy_to_srgb(double x, double y, double Y, double *r, double *g, double *b); /** * Get the [0, 1] sRGB values of a colour temperature. * * @param fd File descriptor for the colour table. * @param temp The desired colour temperature. * @param r Output parameter for the “red” value. * @param g Output parameter for the green value. * @param b Output parameter for the blue value. * @return 0 on succeess, -1 on error. * * @throws 0 The file did not have the expected size. * @throws EDOM The selected temperature is below 1000 K. */ int get_colour(int fd, long int temp, double *r, double *g, double *b);