bake Vray shaders to PBR maps (metal/roughness)

[rasmus]

Hi @ll,

i'm currently trying to bake a simple PBR texture set from a handful of objects with multiple vray shaders. All objects are already layed out on a single UV sheet.
With the baked outputs i want to create realtime objects in painter/sketchfab, that resemble the original object rendered in vray as closely as possible.

For now all the maps i need are:

albedo
metalness
roughness
normal
AO (optional)

Now within the max baking dialogue i dont't see output entries for those but only stuff that looks like compositing Elements instead and some "...bake" maps, that don't make sense to me? Which ones would correspond to the standard PBR material channels to use in Substance designer / sketchfab / marmoset ?

kind regards, and thx in advance,
Rasmus

[hermit.crab]

Here is a list of the corresponding pass elements in V-Ray:

1. Albedo - VRay doesn't have this type of render element, though it can be decently approximated by adding the diffuse filter and the reflection filter. However, you would need to measure the values to find which of them exceed 1.0 and map them accordingly (0-1) through an expression node in Nuke f.e.
2. Metalness - this thread should clarify the situation
3. Roughness - VRayMtlReflectGlossinessBake (the result may be inverted, refer to this topic)
4. Normals - VRayNormalsMap
5. AO - VRayAOMap

[rasmus]

Thanks for your answer Alex,

We have a high demand of PBR conform, realtime assets from our offline renderings, so since all the baking and converting to metal/rough workflow is currently very time consuming and vulnerable to errors let me ask:

Does Chaos have plans on integrating native metal/rough export support in the future or not???... I know of other tools out there like the babylon exporter for 3dsmax but it only supports max Standard and Arnold materials.

kind regards,
Rasmus

[Karol.Osinski]

I am trying to bake VRay Layered Texture and my diffuse pass is giving me wrong results both on CPU and GPU. I don't remember having this problem on V-Ray NEXT.

I am using metalness / roughness workflow btw.

V-Ray 5 for Maya 2020.

[Karol.Osinski]

Same thing is happening after connecting a SINGLE texture via Maya Layered Texture node.

[Karol.Osinski]

Found out that the problem is using Metalness slider. Here is the diffuse pass with Metalness on 0.

Is this a bug?

btw I am sorry for spamming on in the wrong section.

[hermit.crab]

Karol.Osinski It is normal. Happens with a direct link to a file texture and also in Next. Summing the passes seems to produce correct results - try it out on your end.