F A Q
Why are some of my generated images black or contain only few bright pixels?
That's normal. Some values for a-d lead to "fixed-point-attractors".
Maybe I'll detect them in future releases.
Done. (1.0 beta4)
What formulas are used to generate these attractors?
x2 = sin ( a * y1 ) - cos ( b * x1 )
y2 = sin ( c * x1 ) - cos ( d * y1 )
In future releases more formulas will be available.