Issue with light and shadow mapping on mesh brought in from Blender

[corah94149982]

So I am incountering a situation in which a mesh that I am bringing into Substance Painter has a specific part of the geometry that appears to have the light and shadow flipped from what is happening with the rest of the model. 

The part in particular is the the eyesocket/housing on the head of the character (ass seen in the images provided).

Prior to this issue, also was having a problem with some of the polygons appeared inside out, but I was able to solve that by fliping the normals back in Blender and reexporting the FBX file.  

So I'm not sure if this is an issue with the model back in Blender, if this is because of how I imported the mesh to Substance Painter or if it is even an actual issue at all. 

[davescm]

It looks like some of your normals are still reversed. In Blender edit mode, go to the viewport overlays (top right) and turn on normals visibility so you can see what needs to be flipped.

Dave

[corah94149982]

Thank you for the suggestion, Dave.

So I went back into Blender, but it's difficult to tell if the normals are "correct"

The first too images show how the normals are faced out to give me the result in the third image. For some reason there are some coming out of the back of the model which doesn't seem correct.

In the fourth image, I fliped the normals only on the outside most faces where I felt the problem was the most pronounced. But that resulted in said faces appearing transparent in Substance Painter when viewed from head on.

At this point, I think I can just rebuild the object, which I don't think would take me that long. 

[davescm]

Hi

It looks like you have reversed normals but the indicators are coming through the model on the opposite side to the face. You can shorten the length of the lines to make them easier to see. I  would have expected the normal indicators to look something like this :

Dave

[corah94149982]

That's what I would have expected as well, but the when the normals are positioned like that it results in the faces being transparent. 

[davescm]

Did you unwrap again after correcting the normals?

Dave

[corah94149982]

Yes I did, I reeported the mesh as an FBX file and reimported it into Substance Painter

[davescm]

Can you post a link to the fbx file?

Dave

[corah94149982]

Here it is

[corah94149982]

Here is the FBX file for the whole model 

[davescm · Accepted solution]

I downloaded the eye socket model. The problem is that you have a negative scale in Blender on the eye socket object which is reversing the faces. To fix it:

In Blender :

1. Use Ctrl+A and apply the Rotation and Scale

2. Change to Edit mode and Select All

3. Recalculate the normals outside

4. Unwrap again

5. Export the fbx

That should import OK into Painter.

Dave

[corah94149982]

That did it!
Thank you so much for the help, Dave. I really appreciate it

[davescm]

You're welcome 🙂

Dave