Help with outline Post process and UE4 water system

Westbarbary

Hello Everyone

Does anyone know why my outline post process wont work underneath unreal 4's water system? I'm at a loss and would appreciate some help

Many thanks
Ross

Benjammin

Someone else could explain it more technical terms, but:
The unreal water shader isn't actually translucent - its doing a trick where it projects what's underneath onto the water plane. 
This all happens prior to the point where the outline post process happens (its right there in the name - post process) - the depth data you need to draw outlines doesn't exist below the water, because its actually an opaque plane.

Alex_J

might be able to get around it by using a stencil mask in the outline post process material: 
How to Create Masks With the Custom Stencil Buffer | Tips & Tricks | Unreal Engine (youtube.com)

Westbarbary

Thankyou @Benjammin is it possible to get the unreal water system to read the depth data below? 

Benjammin

Westbarbary said:

Thankyou @Benjammin is it possible to get the unreal water system to read the depth data below? 

Maybe? If so, its beyond my level of expertise. I suspect not, simply because that shader is designed to be cheap.

Westbarbary

@Benjammin Thanks again, I'll stick with my own water shader 🙂

poopipe

Alex_J said:

might be able to get around it by using a stencil mask in the outline post process material: 
How to Create Masks With the Custom Stencil Buffer | Tips & Tricks | Unreal Engine (youtube.com)

that's probably where i'd start - simply don't include the water 

Westbarbary said:

Thankyou @Benjammin is it possible to get the unreal water system to read the depth data below? 

There is/was a node for testing depth behind a surface that looks like it's specifically intended for this purpose on (probably) 5.2.  I cant remember what it was called but if you search for depth in the materials nodes it should come up