Recursive Image Sampler Kangaroo

Hi all,

I'm trying to create a circle packing definition where the circle radii change throughout the kangaroo iterations, based on an image sampler. I thought I could have an image sampler grid in the background, and have the packed circle centers constantly referencing closest point from IMG sampler and changing to its radius. But I don't know how to push that logic through Kangaroo. Is this possible without scripting?

Thanks for any feedback!