DistanceMap is slow

The GPU-accelerated approach to drawing distance maps is in many cases inferior to approaches like in MorpholibJ. Use this function as alternative:
https://clij.github.io/clij2-docs/reference_morphoLibJChamferDistanceMap

Start by reading the linked MorpholibJ ChamferDistanceMap reference and locating the DistanceMap implementation in the repository. Compare the current GPU-accelerated approach with that alternative; done should mean DistanceMap uses or exposes the faster approach in the cases described by the issue, with its behavior verified against existing checks if available.

Written by the indexing model from the issue text.