After effects: Polar Coordinates

Im aware that this effect change the coordinate system from the cartesian to the polar. My question is if there is a way to change the function of the polar plane, because this effect only create a circumference, the effect change each (x,y) point to a (r,θ) point starting in the polar axis. But the function is r=radius. So there is a way to change it? for example r=cos(2θ), to create different shapes, not only circumferences. And if this is not allowed, there is a way to change the parametrization of the (x,y) plane to a different one that the polar, because the polar is x=cos(θ), y=sin(θ), with 0 <= θ <= 2π . So there is a way to change it for example to x=cos³(θ), y=sin³(θ), with 0 <= θ <= 2π this would create the shape of astroid. If any of this is allowed, there is another effect that can make something of this? or there is a way to change the source code of the Polar Coordinates effect, to make this changes?

thanks