DataMuseum.dk

top - metrics - download

    Length: 2828 (0xb0c)
    Types: TextFile
    Names: »lunar.c«

└─⟦a0efdde77⟧ Bits:30001252 EUUGD11 Tape, 1987 Spring Conference Helsinki
    └─⟦this⟧ »EUUGD11/euug-87hel/sec1/month/lunar.c« 

TextFile

/*
 * Modification History 
 *
 * Origional Author:  Tom Stoehn@Tektronics[zeus!tims] 
 * Modifications by:  Marc Ries@TRW[trwrb!ries] 
 *
 */

#include <curses.h>
#include <math.h>
#include <sys/types.h>
#include <time.h>

/* Globals. */
double          Fraction;

/* Linked in later. */
time_t          time();
struct tm      *localtime();


#define LINES		24
#define WIDTH		80
#define CENTER		((WIDTH - 2 * LINES) / 2)
#define BRIGHT		'@'
#define LEDGE		'('
#define REDGE		')'
#define FULL		0.5
#define TwoPi		(2 * 3.14159)
#define ZERO		0.03

extern short    month, day, year;

long
Calculate(julian, year, hour, minute)
	long      year, julian, hour, minute;
{
register long   Length;
register long   Phase;
register long   Delta;
register long   offset;
	/*
	 * time_t		 tick; 
	 *
	 * static short called_before = 0; 
	 *
	 * if (!called_before) { tick	= time((time_t *)0); tm		=
	 * localtime(&tick); called_before = 1; } else { tm->tm_yday++; }
	 * julian	= tm->tm_yday + 1; year	= tm->tm_year - 78; hour
	 * = tm->tm_hour; minute	= tm->tm_min; 
	 */

	year -= 78;
	Length = (double) 2551 / 60 * 1000 + (double) 443 / 60;
	offset = ((year * 365L + julian) * 24L + hour) * 60L + minute;
	Delta = offset - (273L * 24L + 13L) * 60L + 23L;
	Phase = Delta - (Delta / Length) * Length;

	Fraction = (double) Phase / Length;
	return (Phase);
}

int
CharPos(x)
	double          x;
{
register int    i;

	i = x * LINES + 0.5;
	if ((i += LINES + CENTER) < 1)
		i = 1;
	return (i);
}


Draw()
{
register char  *p;
register int    i;
register int    end;
register double y;
register double cht;
register double squisher;
register double horizon;
register double terminator;
char            Buffer[256];
int             line = 1;

	/* Clear screen? */
	clear();

	if (Fraction < FULL)
		squisher = cos(TwoPi * Fraction);
	else
		squisher = cos(TwoPi * (Fraction - FULL));

	cht = (double) 2.0 / (LINES - 6.0);
	for (y = 0.93; y > -1.0; y -= cht)
	{
		for (i = sizeof Buffer, p = Buffer; --i >= 0;)
			*p++ = ' ';
		horizon = sqrt(1.0 - y * y);
		Buffer[CharPos(-horizon)] = LEDGE;
		Buffer[i = CharPos(horizon)] = REDGE;
		Buffer[++i] = '\0';
		terminator = horizon * squisher;
		if (Fraction > ZERO && Fraction < (1.0 - ZERO))
		{
			if (Fraction < FULL)
			{
				i = CharPos(terminator);
				end = CharPos(horizon);
			} else
			{
				i = CharPos(-horizon);
				end = CharPos(terminator);
			}
			while (i <= end)
				Buffer[i++] = BRIGHT;
		}
		mvaddstr(line++, 1, Buffer);
	}
	move(LINES - 1, 0);
	refresh();
}

lunar()
{
long            yday;
extern int      lflag;

	yday = (long) (days_since_jan1(month, day, year) + 1);
	(void) Calculate(yday, ((long) (year - 1900)), 11L, 0L);
	Draw();
	refresh();
	if (lflag) {
	    clear();
	    endwin();
	    exit(0);
	}
	else {
	    get_char();
	    clear();
	    print_screen();
	}
}