Tutorial: Building Streets in the Rain with UE4

How does one set up a nice-looking rain inside Unreal? Let’s study a nice guide to building a paved street in the rain with the help of UE4 and a couple of substances by Koola.

Here goes the guide:

First, I created the textures in substance designer.

I just wanted to test the rain effect so I used the “Roman Street Pavement” substance from Substance Source as a base. I simply plugged it in a “water level” node to make a wet version.

For the water ripples effect, I used a substance from Nicolas Wirrmann for generating the normal map.

I haven’t found how to export an animation with substance designer so I exported 16 images and made the flipbook in photoshop.

Here is the material in Unreal.

The scene setup is really simple, some planes for the floor, walls and the “street lights” (a night street photo plugged in the material emissive channel).
I used a BoxReflectionCapture for the reflection, an ExponentialHeightFog for a bit of volumetric fog and a PostProcessVolume.

For the lighting, It only comes from the 2 planes with the street photo (the lights are baked).

Then, you just have to add some rain particles (with this material setup).
The normal map used can be found here /Engine/Functions/Engine_MaterialFunctions02/ExampleContent/Textures/SphereRenderNormalsMap

And voila:

The guide was originally published here.