Rivers and Custom Bodies
Rivers and Custom bodies are currently beta features are they don’t yet support all of the features I’d like them to (such as automatic interaction, underwater post processing, or caustics) so they don’t have a full documentation page. I have had a couple questions about how to use them though so wanted to put this page together for anyone interested in working with them.
The key thing to know is that both custom bodies and rivers are child classes of UIWSWaterBody and so have most of the same options and features available.
How to create a river
Rivers are built on the UE4 Spline component and can be drawn out as with any other spline by manipulating and alt dragging the spline points.
These are super straight forward - simply set your custom mesh and you’re good to go. An idea use for a custom body would be if you have a pre modelled river with a dynamic shape etc and want to add interaction to it. You’ll of course need to make sure it has enough tesselation if you want to use WPO ripples, but set any mesh as the custom mesh and it will ‘just work’.
Allow Camera Under
Because these body types don’t yet have automatic under water post processing, if you don’t want to manually place post processing volumes you can leave Allow Camera Under un-ticked and the surfaces will block collision on the camera channel so a spring arm camera can’t be moved under water etc. I have plans for underwater post processing with the river body, but probably will leave it up to the user where custom bodies are concerned because by nature it will be hard to account for all body shapes in a way that’s actually useful for most people.