Sinusoidal rotation map
FractalPark uses z(n+1) = exp(0.55 i) * (z(n) + 0.28 sin(z(n))) + c. The sine term is a 0.28-weighted perturbation of z, not a replacement for it. The fixed multiplier rotates the whole perturbed orbit counter-clockwise by 0.55 radians (about 31.5°), then c shifts the result.
For z₀ = 0, sin(0)=0, so the parenthesized perturbed term is zero; rotating zero still gives zero, and only c remains: z₁ = c. After that, complex sine can grow: the magnitude of sin(a + ib) contains terms up to cosh(b). A point with a large imaginary coordinate can receive a large sine perturbation and is more likely to escape.
The 0.55-radian rotation is fixed in the formula, not adjustable by the user. As an implementation detail rather than part of the idealized recurrence, FractalPark clamps the input imaginary component to ±80 and rounds each output component to a 1/16 grid.


