1
$\begingroup$

I am working on a project that necessitates an automated export of blender objects with materials to basically any file format that supports diffuse and roughness maps. However, some objects have topology too complex to be smart-UV unwrapped and thus cannot be texture baked on. To remedy this, I was able to use .fbx to export vertex colors. Is there a method of annotating vertices with roughness and a file format that supports it? In essence, I need to avoid the use of UV unwraps but still export roughness and diffuse data.

$\endgroup$

1 Answer 1

0
$\begingroup$

Once your roughness is tuned to your liking, (depending on what facilities you have to further adjust it in your destination application,) you can plug it straight into the material output, and bake its resulting Emission into a Color Attribute you've set up for the purpose:

enter image description here

On the left, the original texture. On the right, picked up from the baked Attribute:

enter image description here

If you needed to, with a Combine RGB you could arrange your shader-tree to feed 3 float/monochromatic parameters into the R,G,and B of a single Color Attribute.

The attribute's resolution will obviously depend on the density of your mesh.

$\endgroup$
5
  • $\begingroup$ This is great, but do you (or anyone else reading) know if its possible to export color attribute data out of Blender? As far as I know, shader node IO only supports image textures during export (and remember that I am unable to uv-unwrap/texture bake). I could export vertex colors/color attributes via .fbx, but the question remains of how I could link the per-vertex roughness data in my roughness color attribute layer to whatever fbx uses internally to represent roughness. $\endgroup$
    – user167693
    Commented May 30, 2023 at 18:07
  • $\begingroup$ @user167693 Ahh, I see, I've slightly misunderstood you, haven't I? This is more like a .fbx question.. $\endgroup$
    – Robin Betts
    Commented May 30, 2023 at 18:14
  • $\begingroup$ @user167693 What application are you aiming at? $\endgroup$
    – Robin Betts
    Commented May 30, 2023 at 18:17
  • 1
    $\begingroup$ Fbx was just an example - quite literally any file format or application that might support this pipeline would be fine. Basically I just need to get roughness and diffuse/color data into any file format out there without utilizing UV unwraps. one hacky solution maybe would be to write my own uv unwrapper that maps all the points into a completely disjoint texture map and then generate a roughness maps from there, but I wanted to see if there were any other options $\endgroup$
    – user167693
    Commented May 30, 2023 at 18:31
  • $\begingroup$ @user167693 a quick search suggests most renderers in most applications can pick up vertex color layers from .fbx , and use them for whatever you like? .. but that would mean checking with them, not Blender. (Needless to say.. the .fbx can be exported from Blender and re-imported, 'Roughness' survives as a named layer.) $\endgroup$
    – Robin Betts
    Commented May 30, 2023 at 18:55

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .