UE4 - material blending, vertex painting and LOD's

GlowingPotato

Hi,

I'am planning a level inside ue4 and I would like to use vertex painting on walls to blend multiple materials together.
I do know that I'll need a fair amount of vertexes to have nice results when blending the materials, but, should I disable LODs for assets that will have vertex painting ?

Yerus

LODs are an optimization technique, if you disable them you might have terrible performance, besides sth called 'overshading' which is a uggly visual glitch, but disabling LODs might be okay for short distances like interior scenes. Idk about vertex painting in UE, but why don't use ordinary baked textures instead?

GlowingPotato

baking textures is not a option for modular environments that needs variation. specially with a small team working on it. 

poopipe

If you're talking about walls and floors that are basically just planes /boxes or other simple geometry with a few verts added for painting there's not much point in lodding them.  

 Lodding anything architectural  with under a couple of hundred tris is of dubious value unless you can see a shit load of them at once. 

gnoop

Or  you can just bake unique low res texture atlas for a big shared distant lod.   The one combining  distant lods of many objects into a single one for less draw calls and total number of objects in a frame.     I recall we did so in late 90th in my first game job.        Not sure why this technique has been  totally fallen into oblivion now.    

poopipe

It hasn't ,it's done everywhere - usually with no user input 

Unreal's HLOD system does something along those lines, simplygon's runtime system can do it and several of the proprietary engines I've worked on did it.

Any time you hear the terms imposter or mesh aggregation it basically means the same thing. 

gnoop

Wow, I didn't know Unreal is doing so . Always thought it's a huge omission there.    Thanks poopipe

20 years ago we even called it  same "Hierarchical LODs"    In every next company I worked for people just shrugged so I thought it's kind of ancient forgotten technique.