{{:en:kahn_joel_eye_in_vortex.png?200}}
Eye in Vortex by Joel Kahn (June 2010)\\
Modified 2013-02 for version 0.9.9.45 and later
<code>
# Contributed by Joel Kahn
cls
clg
l=700
w=500
graphsize l,w
dim f(8)
f[0]=0
f[1]=0
f[2]=17
f[3]=0
f[4]=17
f[5]=1
f[6]=0
f[7]=1
m1=1
m2=2
x1=l/2
y1=w/2
x2=x1+1
y2=y1+1
qq1=0.99999
q1=1.34
qq2=0.99998
q2=1.33
vv1=0.011
v1=0.0
vv2=0.012
v2=-0.1
s1=1.411
s2=1.412
c1=0.0
c2=2.0^24.0
for d=1 to 25000
   m1=m1+1/m1
   x1=x1+s1*cos(m1)
   y1=y1+sin(m1)
   c1=c1+6.01
   q1=q1*qq1
   v1=v1+vv1
   color rgb(c1\256\256%256, c1\256%256, c1%256) 
   stamp x1,y1,q1,v1,f
   m2=m2+1/m2
   x2=x2+s2*cos(m2)
   y2=y2+sin(m2)
   c2=c2-6.02
   q2=q2*qq2
   v2=v2+vv2
   color rgb(c2\256\256%256, c2\256%256, c2%256) 
   stamp x2,y2,q2,v2,f
next d
</code>