Ideally, I’d like something to output something kind of like a normal map, but with each pixel encoding a vector pointing in the direction of flow for water.
I figured I could hack something together if I could perform a cross product on the normal map in app, is that a thing I can do? Is there a way to do what I’m after directly?
You can use the “Composite” device to "decomposite"the “create water” or any other water output. From there you can further decomposite to get motion vectors (somewhat, in the form of RGB images…). You can try creatively wrangling that data to produce a normal map according to your spec. I’ve never tried this method personally though.