Trouble with metallic surfaces

HashBrownHamish

I'm new to unreal engine and i am learning to build my first scene. So to try the material editor i imported a mesh and some unique asset textures along with it. So every time i try an object with metallic surfaces light reflects in a different manner to my visualisation tool (note here it is marmoset but quixel's 3Do and the UE4 lightning preset is practically the same)




This must have something to do with how specular and diffuse is handled in UE4 because the albedo from quixel ressembles the color shown in UE4. But i gave quixel the preset to export for UE4 so i'm confused.

Here is the material in UE4

leleuxart

Did you start your DDO project with the UE4 preset as well? Selecting the appropriate preset in the beginning tells DDO which maps to load by default, which in this case it seems like you loaded something using the Specular/Gloss workflow, instead of the Metalness/Roughness one that UE4 supports. 

I would read up on the differences between the two workflows, because while the results are nearly identical, the workflows are different and not every renderer supports both(like 3DO and Toolbag). Unreal 4 uses only Metalness, with the Specular input left as a modifier for reflectivity variation. If you do use it, you use it as a Constant 1 value offsetting the default 0.5. However, it's generally best to leave it alone. 

Take a look at these two articles by the awesome Joe Wilson. They should steer you in the right direction, but I'd also read up on the UE4 documentation for PBR since every engine will usually have their own little issues and workarounds. 

https://www.marmoset.co/toolbag/learn/pbr-theory

https://www.marmoset.co/toolbag/learn/pbr-practice

Cay

The thing with metals is.. what you see of them is their reflection. Unless you create an environment with similar warm colors in Unreal, you won't get it to look the same as in Toolbag.
And apart from that.. you need to change it to metalness as leleux mentioned.

AndrewAlexArt

Be shure that you load your metallic and roughnes textures with linear gamma. Turn of sRGB on every Metallic/Roughness texture in UE4 and set texture sampler type for that textures as Linear Color

Hope it's help

Tetranome

AndrewAlexArt said:

Be shure that you load your metallic and roughnes textures with linear gamma. Turn of sRGB on every Metallic/Roughness texture in UE4 and set texture sampler type for that textures as Linear Color

Hi Andrew - where did you hear this? New info to me, just curious!
Thx

Obscura

Tetranome said:

AndrewAlexArt said:

Be shure that you load your metallic and roughnes textures with linear gamma. Turn of sRGB on every Metallic/Roughness texture in UE4 and set texture sampler type for that textures as Linear Color

Hi Andrew - where did you hear this? New info to me, just curious!
Thx

"When packing multiple Mask Textures into a single texture, you should Disable sRGB as your masks should not be Gamma corrected"

This is from the official documentation.

"Gloss/Roughness/Microsurface maps should generally be linear space (sRGB off), but its not a big deal if you use sRGB/Gamma space."

And this is from the Physically based rendering encyclopedia.

Masks compression would do the same, put your texture into linear space. Or there is user interface2d that is uncompressed.



Also, yeah, to get closer results, make sure you are actually matching the lighting so you have the same cubemap or sky, lights etc. And make sure you view and use the masks in the same color space as in DDo.

CB_Productions

Do you have a reflection capture in your scene? Are your lights set to static/stationary or movable?

Vailias

The biggest issue I see is you're plugging in the maps expecting a specular color workflow.  That's not how Unreal 4's shader works. It's built around a metalness workflow. 
read:
https://docs.unrealengine.com/latest/INT/Engine/Rendering/Materials/PhysicallyBased/

You'll want to reauthor your maps to work with the shading model you're actually outputting to. 

Tetranome

@Obscura
Thanks!