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/**
* Copyright © 2016 Mattias Andrée <maandree@member.fsf.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 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 <http://www.gnu.org/licenses/>.
*/
/**
* 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);
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