ZXASCII
AUTO -1
PROG demos:3d/circle series stereo
CHANGED FALSE
10 s=scrw/800,w=(scrw/2)-(s*64),a=0.1,ofs=-1
20 paper 1: screen lock: cls
30 cx=scrw/4,cy=scrh/2
40 for i=1 to 2
50    for f=1 to 30 step 1
60       r=w/2/f,x=cx-w/2+r,y=cy
70       for g=0 to f-1
80          xn=x+g*r*2,an=a+g*0.05
90          xn=cx+(xn-cx)*cos an-(y-cy)*sin an
100          yn=cy+(xn-cx)*sin an+(y-cy)*cos an
110          circle ink 225+f;xn+ofs*f/2*s,yn,r fill
120       next g
130    next f
140    ofs*=-1,cx+=scrw/2
150 next i
160 a+=.01
170 wait screen:
180 GO To 20