The motivation for the first version of WrapMap was indeed to generate rims for bumpmaps.
There is a neat trick you can use to generate a really complex rim with little effort:
- In the bitmap layer, draw a black-to-white gradient
- Open the colors curves tool on that layer, and use it to define you rim section graphically:
This will produce something like:
- Apply Wrapmap on your selection to produce the bumpmap:
- And run the bumpmap filter: