without spending out money, im a bit useless as i am using realflow as a plugin, if you can afford one like a student one its a godsend (obviously) for things like this!
However, other than realflow i dont know. I did though, find this post on another forum. Posted by someone called Olcho.
'For the river itself I believe you could use a texture - usually an animated bump and/or displacement (sometimes you don't even need displacement) will do the trick. If you want to make foam, then the textures will be more complex, but that's the way I woud go.
Now for the integration of floating objects there's a very cool trick, using Fluids. Make a 2D fluid container with the Y size big enough to cover all the river and the riverbed, remove everything but the velocity. Paint some velocity to mimic the river flow direction. If you want to add some logs to float in the river, make them rigid bodies and connect them to the fluid force. If you have rocks in the river, you can make them collision objects with the fluids and the velocity will work its way around the rocks. If you want the logs and rocks to "emit" foam while they are in the river, you can make a 2D fluid texture and connect it to the river's color, bump and may be incandescence - you can pretty much experiment with all that stuff.
There's actually a very good video tutorial I think from Gnomon that describes all that - very cool stuff'
Hope this helps sorry
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