SCREEN 12
pi = ATN(1) * 4
t0 = 50
'WINDOW (-t0 * .4, t0 * 2.1)-(t0 * 2.4, -t0 * 0)
WINDOW (-t0 * .25, 3 * t0)-(t0 * 1.25, -t0)
beta = .6

opnieuw:
COLOR 6: LOCATE 3, 25: PRINT USING "(velocity: ##.##c"; beta;
PRINT USING "    max. distance: ###.# LYs)"; beta * t0
gama = 1 / SQR(1 - beta * beta)
t0 = 50
t = t0 / gama

x = 0
FOR y = 0 TO t0
'thuisblijver
LINE (0, 0)-(0, y), 15: 'LINE -(0, 2 * t0), 8
'reiziger
LINE (x, 0)-(x, 2 * t), 0: PSET (x, y / gama), 8
x = beta * y
LINE (x, 0)-(x, y / gama), 6: 'LINE -(x, 2 * t), 8
COLOR 7: LOCATE 2, 1: PRINT USING "age homebody: ###.# Ys"; y
COLOR 6: LOCATE 3, 1: PRINT USING "age voyager : ###.# Ys"; y / gama
FOR dum = 1 TO 100000: NEXT dum
NEXT y

FOR y = t0 TO 2 * t0
'thuisblijver
LINE (0, 0)-(0, y), 15: ' LINE -(0, 2 * t0), 8
'reiziger
LINE (x, 0)-(x, 2 * t), 0: PSET (x, (y - 1) / gama), 8: PSET (x, (2 * t0 - (y - 1)) / gama), 8
x = beta * (2 * t0 - y)
LINE (x, 0)-(x, y / gama), 6: 'LINE -(x, 2 * t), 8
COLOR 7: LOCATE 2, 1: PRINT USING "age homebody: ###.# Ys"; y
COLOR 6: LOCATE 3, 1: PRINT USING "age voyager : ###.# Ys"; y / gama
FOR dum = 1 TO 100000: NEXT dum
NEXT y



wacht:
SLEEP: a$ = INKEY$
SELECT CASE a$
CASE "+": IF beta < .8999 THEN beta = beta + .1
CASE "-": IF beta > .11 THEN beta = beta - .1
CASE " ": END
CASE ELSE: 'herbegin
END SELECT
CLS
GOTO opnieuw
END

END