Warp Along Mask

[WAS]

Is it possible to warp terrain outside of a mask. For example. Lets say I have a disc, and I want the terrain to warp around it and stretch, is that possible? How would you do that? I imagine blue nodes, but not sure what does what or where to begin.

[Dune]

Is simple, if you can live with certain limitations.

[WAS]

Thanks Dune, see if this can work.

[Hannes]

Ulco, did you use this method to make your surf in your beach presets?

[Dune]

 
Actually not.