Transluscent blend mode affect roughness / semi-transparency on the whole mesh

zacharie_zuwala
Wed, 31 May 2023 05:22:00 +0000
Asset Creation

Hello, I was creating a game-ready asset, while working on the textures with substance painter, I exported the textures to Unreal Engine for a quick look-dev and see how it looked in the render engine.

My material consist of multiple channels such as Base color, Metallic, Roughness, Emissive, Opacity, Normal and Ambient Occlusion.

As I have an opacity channel for the glass bottles, I changed the blend mode to “Transluscent” and the transluscency lighting mode to “Surface TransluscencyVolume”, to keep my roughness/metallic/ect channels. (is that the right way to do it? )

But I saw that when changing the blend mode to Transluscent, it affected my roughness a lot :

“Opaque”

“Transluscent”

“Transluscent”

“Opaque”

Also there seem to be a semi-transparency applying everywhere on my mesh :
“Transluscent”

“Opaque”

Here is my shader setup :

I saw this answer to what seem to be the same issue :

I haven’t tried it yet, but it will just end up as a nightmare if I had to separate each part that has transluscency to it, especially for placing these elements in the scene.

So is there anything that would solve this problem ?

Bonus issue : I haven’t looked in it too much yet, but after exporting my textures, I saw that there was some elements with missing textures, the whole thing is a merged mesh, I’ve checked the uvs and everything seems correct, they do have texture in the substance file, and I’m also using udims, so if you have a solution to this as well…