Calculates a shade of gray from the given number of required iterations
at a point in a fractal and the maximum number of iterations given to
the constructor.
Performs the actual calculation of the number of required iterations to
determine divergence of a certain sequence defined using the specified
complex number.
Calculates the number of required iterations to determine the divergence
of the sequence of points obtained by the recursion
zn + 1 = (zn)2 + c
where c is the point passed to the setDefiningPoint method and is
constant during the calculation of the fractal and z1 is a
point determined by screen coordinates.
Calculates the number of required iterations to determine the divergence
of the sequence of points obtained by the recursion
z1 := 1, zn + 1 = (zn)2 + c
where c is the specified complex number.