From some time ago , but I changed the calculus of the orbit ..
tB - TBGL module (Petr Schreiber) and O2 of course. (3D animation)
the core is only :
For k=1 To maxit
dup=x
x=x*x-y*y + cr
y=dup*2*y + ci
orb=abs(x*y)
If orb > 6 Then
Exit For
EndIf
Next
d=orb
best, Rob
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