Hello,
I'm trying to understand how to re-create this effect (attach).
This example was done thanks to one of Oleg S. scene ... I figure out what to plug in my scene to make it working on a procedural terrain.
The problem is that I can't make it working on an imported heighfield terrain. (well heihfied + some terragen goodies). As I don't really understand the blue node network, I have no idea what's going wrong (basically there are foam everywhere

).
Does anyone has a very simple demo scene about how create this kind intersection mask between an heighfield terrain and a lake object ?¿

( (I dont need the waves displace, or the voronoi fractal foam ... just a simple mask).
Need some help guys