Mesh decals and Nanite

Hi there! I was wondering what is the best way to use mesh decals (floating geo that uses deferred decal material for extra normal map details) in Unreal Engine 5 with Nanite? Basically similar system that Star Citizen and Starfield etc are using.

I’ve been using similar approach in Unreal Engine 4 and there are lots of advantages with that. In a nutshell to have a texture atlas full of generic details that I can place how I want/need. Unfortunately Nanite is not supporting materials that are using translucent blend mode. I’ve been waiting that Epic would manage to get that working somehow but I guess it’s just too complex. Transparent materials are always very tricky to handle.

Only solution I have found is to split that decal geo into a separate mesh and place that on top of the actual mesh in Unreal. That way I can use Nanite for the mesh underneath and regular mesh for that decal mesh. This approach is very tedious and UE5 is handling LODs so badly for regular meshes that the end result is not looking good at all.

Is there any way to use Nanite and deferred decals together that would actually work or do I just have to abandon this workflow? I’m sure I’m not the only one who is wondering this.

My method is using a masked surface material with an opacity mask for my decal sheet. You can experience some z-fighting if your planes are not spaced far enough away from your mesh, which you can fix by either…spacing them further away, or adjusting the Position Precision under Nanite Settings on the static mesh. Hopefully this helps

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