Transparent Water Surface with Bathymetry

I’m trying to make a transparent surface for the ocean to use with Bathymetry terrain, I’m using World Terrain for the ocean surface and Bing Maps Aerial for the imagery. I can’t figure out how to make the Water Material transparent with the OverlaysAndClippingAndWater material, and if I use a completely different material with just color and opacity I can’t figure out how to deal with the tile mesh edges overlapping through the “ocean surface”.

To hide the mesh edges I tried to use VertexNormal(B) but it does not work.

I don’t have a quick solution for you. Unreal distinguishes between translucent and non-translucent materials, so you’d probably at least have to copy OverlaysAndClippingAndWater and switch it to a translucent material. But yeah, the skirts at the tile edges are going to be visible and distracting with any sort of translucent rendering. You didn’t say what went wrong with the VertexNormal-based approach, but it might be possible to make something like that work (I haven’t tried). If you’re only concerned with a small-ish area, you might consider using a simple sphere - carefully placed and scaled - for the ocean surface rather than Cesium World Terrain.

The VertexNormal-based approach didn’t change how it looked, I’ve developed a workaround solution using a big sphere that scales and moves with the surface though.