UE Water system - Controlling tiles & material instances

Hi all,

Trying to find additional information on how UE 4.26’s water system controls the water tiles that assign different material instances. (presentation link of tile workflow: 4.26 Water And Volumetrics Preview | Inside Unreal - YouTube)

I’m trying to add additional material instances around shorelines, as well as import my own custom heightmaps & flowmaps for rivers from other 3D programs instead of reading that data straight off the native UE water actors. So i’d like to better understand the innder workings of the water system so I can customize it.

Any help on this would be much appreciated,

Cheers,