124 lines
2.9 KiB
C
124 lines
2.9 KiB
C
/* redshift.c */
|
|
/* Copyright (c) 2009, Jon Lund Steffensen <jonlst@gmail.com> */
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <time.h>
|
|
#include <locale.h>
|
|
|
|
#include "solar.h"
|
|
#include "colortemp.h"
|
|
|
|
#define MIN_LAT -90.0
|
|
#define MAX_LAT 90.0
|
|
#define MIN_LON -180.0
|
|
#define MAX_LON 180.0
|
|
#define MIN_TEMP 1000
|
|
#define MAX_TEMP 10000
|
|
|
|
|
|
#define USAGE \
|
|
"Usage: %s LAT LON DAY-TEMP NIGHT-TEMP [GAMMA]\n"
|
|
|
|
#define DEG_CHAR 0xb0
|
|
|
|
|
|
static void
|
|
printtime(time_t time)
|
|
{
|
|
char s[64];
|
|
strftime(s, 64, "%a, %d %b %Y %H:%M:%S %z", localtime(&time));
|
|
printf("%s\n", s);
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
/* Check extensions needed for color temperature adjustment. */
|
|
int r = colortemp_check_extension();
|
|
if (r < 0) {
|
|
fprintf(stderr, "Unable to set color temperature.\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Init locale for special symbols */
|
|
char *loc = setlocale(LC_CTYPE, "");
|
|
if (loc == NULL) {
|
|
fprintf(stderr, "Unable to set locale.\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Load arguments */
|
|
if (argc < 5) {
|
|
printf(USAGE, argv[0]);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Latitude */
|
|
float lat = atof(argv[1]);
|
|
if (lat < MIN_LAT || lat > MAX_LAT) {
|
|
fprintf(stderr,
|
|
"Latitude must be between %.1f%lc and %.1f%lc\n",
|
|
MIN_LAT, DEG_CHAR, MAX_LAT, DEG_CHAR);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Longitude */
|
|
float lon = atof(argv[2]);
|
|
if (lon < MIN_LON || lon > MAX_LON) {
|
|
fprintf(stderr,
|
|
"Longitude must be between %.1f%lc and %.1f%lc\n",
|
|
MIN_LON, DEG_CHAR, MAX_LON, DEG_CHAR);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Color temperature at daytime */
|
|
int temp_day = atoi(argv[3]);
|
|
if (temp_day < MIN_TEMP || temp_day >= MAX_TEMP) {
|
|
fprintf(stderr, "Temperature must be between %uK and %uK\n",
|
|
MIN_TEMP, MAX_TEMP);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Color temperature at night */
|
|
int temp_night = atoi(argv[4]);
|
|
if (temp_night < MIN_TEMP || temp_night >= MAX_TEMP) {
|
|
fprintf(stderr, "Temperature must be between %uK and %uK\n",
|
|
MIN_TEMP, MAX_TEMP);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Gamma value */
|
|
float gamma = 1.0;
|
|
if (argc > 5) gamma = atof(argv[5]);
|
|
|
|
/* Current angular elevation of the sun */
|
|
time_t now = time(NULL);
|
|
double elevation = solar_elevation(now, lat, lon);
|
|
printf("Solar elevation is %f\n", elevation);
|
|
|
|
/* Use elevation of sun to set color temperature */
|
|
int temp = 0;
|
|
if (elevation < SOLAR_CIVIL_TWILIGHT_ELEV) {
|
|
temp = temp_night;
|
|
printf("Set color temperature to %uK\n", temp_night);
|
|
} else if (elevation < SOLAR_DAYTIME_ELEV) {
|
|
float a = (SOLAR_DAYTIME_ELEV - elevation) /
|
|
(SOLAR_DAYTIME_ELEV - SOLAR_CIVIL_TWILIGHT_ELEV);
|
|
temp = (1.0-a)*temp_day + a*temp_night;
|
|
printf("Interpolated (%f) temperature is %uK\n", a, temp);
|
|
} else {
|
|
temp = temp_day;
|
|
printf("Set color temperature to %uK\n", temp_day);
|
|
}
|
|
|
|
/* Set color temperature */
|
|
r = colortemp_set_temperature(temp, gamma);
|
|
if (r < 0) {
|
|
fprintf(stderr, "Unable to set color temperature.\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|