Here it goes my pipeline!
From substance painter I export the textures Rough,Opacity,Metalic (Packed) R+G+B
I import texture in the UE4 and in texure editor i uncheck sRGB as it should!
I everything connect in the material editor
R= Rough
G=Opacity
B=Metalic
And texture look fine in photoshop
What’s the problem?
Well the problem is that it does not match the value
SP and UE4
For example, only channel of metalic
does not match SP value and roughness is ok
if you check srgb (In texture editor) then metalic is ok but roughness is wrong
Simpler to me is import separate textures! But it will take precious space!
From the substance buddy:
“Try to put a transform 2D node before your output node in Substance Designer and force the bit depth to 8bits (absolute), see if it improve things”
Actually, if you are exporting from Substance Painter you won’t be able to do that. You can try to export with a different file format like TGA instead (which is 8bits max) instead of PNG (which is 16bits).
There are possibly a few reasons that the textures maybe off, but it boils down to a gamma correction that is done in the image. sRGB corrects the image to an approx. 2.2 power.
So there is actually two ways to very quickly solve this problem in your material.
One is to use the Default Compression with sRGB set to true and in that case take the Roughness Texture and raise it to a power of 1/2.2, like this:
Alternatively you can use the Masked Compression with sRGB set to false and in that case take the Metallic Texture and raise it to a power of 2.2, like this: