Exported Body Roughness Map is Black

[BernhardRieder]

I exported the UE Asset and when checking the Body Roughness map, there is no roughness information. The image is just black with no other values. I also checked all channels. Same problem.

No roughness information. Download & Export Options are checked for the Roughness map.
Hmm… anything else important I am missing here?

Thanks for any little hint,
cheers

[BaboBabo555551]

I have the same problem. Have you figured out the issue yet?

[Dividuum]

Same issue here…

[Dividuum]

For anyone interested, I solved the problem through a neat little hack:
I made a custom material, only added the roughness map in question to the diffuse channel, applied it to a cube.
On the cube I used the “bake material” option to create a new texture out of the material, which I was able to export without a problem

[Jhonathan_27]

Awesome! Thanks!

[Jeremy_RosBroz]

Godsend. Needed to make a hand opacity mask.

[m3trowave]

does anyone know where the bake out material option is in ue5 ?!!

[EL.DAR.CG1]

could some explain me how do i bake the material as texture in unreal 5.1 for exporting the roughness map? is it with the modeling tools baking tool?

[Eugene_Lin]

Forgot to mention the tutorial

Let's Make a Texture Baker in Unreal Engine 4!

[Eugene_Lin]

Hey guys, I encounter the same problem, and after tons of research, I may found the problem.
I think the problem is metahuman body roughness map is composite from normal map, you can find this option in that green map.

So I try to use “Modeling Tool Editor Mode” plugin from the previous reply suggested, but it didn’t work for me. In the end, I found this tutorial to make my own baker machine to successfully bake out the roughness map and export as .EXR format(didn’t know why can’t export into .TGA or .PNG), anyway take the .EXR format file into Photoshop then reExport as .PNG file format and ready to go.

But I found some little issue that is after reExport as .PNG file, it seems to be compressed, and the roughness map color becomes a little bit darker~

Hope it’s useful for you! Sorry for the bad English.

[Riktov_428 (Riktov)]

Thx!

[surfsidegraphics]

Years later, you’re still helping. Thanks!

[Enzodi24]

It might be late, but I haven’t seen a real solution for this issue yet. After much research, I found the solution.

The roughness of the Metahuman texture is generated from the normal map. As Eugene_Lin mentioned, there’s an option in the texture that allows extracting the roughness from the normal map, and in this case, for Metahumans, it specifies that the normal map should be placed in the green channel. However, when exporting, these parameters are not read by Unreal, resulting in a black texture.

When we export the roughness of the head, we get a red color. This still isn’t correct because it uses the same method to generate it, loading it onto the green channel. What we see as red upon exporting is actually the roughness data that belongs only to the makeup.

The solution is:

1. Import all the textures into Substance Painter and use each one in its respective channel.
2. In the roughness channel, use the normal map and add a curvature filter to adjust the contrast as needed.
3. For the head, create a new fill layer with a grayscale filter that only takes the red channel, and add the roughness map exported from Unreal (the red-colored one).
4. Then, in the Texture Set Settings panel, create a new channel called “Coat Roughness” and assign this to the newly created fill layer.
5. Set up the export by creating a texture that combines the regular roughness (created from the normal map) in the green channel, and the Coat Roughness (created from the red texture) in the red channel. This way, you will get a texture containing both pieces of roughness information: the regular texture’s roughness in the green channel, and the makeup roughness for the Metahuman in the red channel.

It’s also important to note that the face texture consists of four other textures that simulate different facial expressions. These should also be combined with the roughness map we created earlier.

After doing all this, import and replace all the textures in the Metahuman materials in Unreal, and everything should work correctly.