Distance Field Flow Maps

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I managed to integrate distance field flow maps into the waterfall using the basic concept from this Unreal Engine Forum Post: https://forums.unrealengine.com/development-discussion/rendering/47456-distance-field-flow-map

I then combined this with the techniques I learned from the free assets on the Unreal Engine Marketplace called River Water Tool with Flow Buoyancy by James Stone: https://www.unrealengine.com/marketplace/en-US/slug/river-water-tool-with-flow-buoyancy

I was also studying up Ryan Bruck's GDC presentation on distance fields and compared with his approach: https://www.gdcvault.com/play/1026262/Technical-Artist-Bootcamp-Distance-Fields

One thing that piqued my interest in Ryan's work is how he included a regular normal map of the small stones which controls the flow of the water. The stones are just part of the landscape material using height data. It's a pretty nifty trick.
Changing the flow of water through the use of the regular normal map in Fortnite.
Although this a pretty cool trick, I won't be including this for my water system. I intend to make my water for general purpose use and not for a specific use such as flowing around stones.

I also followed some of the concepts from this tutorial on 80.lv too: https://80.lv/articles/how-to-make-dynamic-flowing-water-in-ue4/

After studying all of these techniques above, I did a bit of experimenting in the material and this is what I was able to make:


Waterfall with Distance Field Flow. Notice how the water appears to flow around the sphere.

It's now onto working on creating vertex paintable flow maps, the final feature I want to try adding into the water system.

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