ZXASCII
AUTO -1
PROG /demos/Graphics/moire2
CHANGED FALSE
10 z=-0.000001: screen lock
20 DEF FN s(x,y)=SIN(a*sqr(abs(x-cx)^2+abs(y-cy)^2))>0
30 cx=scrw/2,cy=scrh/2,b=5
40 a=.01:
 for x=0 to scrw-1:
    for y=0 to cy:
       if fn s(x,y) then
          plot x,y;x,scrh-y
50       a+=z:
    next y:
 next x:
 z+=.000001:
 wait screen:
 cls:
 GO To 40