MODE 2
Map Reset
For U=0 To 159
 x1=U/128-1.25
For V=0 To 239
 y1=V/128-1
   X=0:Y=X:Z=-2.4
   Do
     k1=Sqr(X*X+Z*Z)-2
     d1=1-Sqr(k1*k1+Y*Y)
     X=X+x1*d1:Y=Y+y1*d1:Z=Z+d1
   Loop Until d1<.005
   v1=Atn(Z/X):u1=Atn(Y/k1)
   sColor(): Pixel U,V
   v1=3.13-v1
   sColor(): Pixel 319-U,V
 Next
Next

Sub sColor()
 p=Sin(Int((u1+v1)*40)*99)*98
 c=15 And ((u1-v1+p)*24*Abs(Sin(p)))
 Color Map(c)
End Sub

Dim integer cm(15)=(0,15,7,1,0,0,0,0,0,0,0,0,0,0,0,0)
Colour Map cm(),cm()
Do
 T=cm(1)
 For i=1 To 15-1:cm(i)=cm(i+1):Next
 cm(15)=T
 For i=1 To 15:Map(i)=cm(i):Next
 Map Set
 Pause 50
Loop