Hi there,
I have a Blender model that’s exported as Wavefront .obj and then imported into Unity. Some of the model’s faces are not showing up even though the normals are correct and pointing outwards, towards the camera. What’s weird, is that if for example, for this side of the roof shown in the screenshot, if I flip the normals so they point inwards, they do show up in Unity. What do you think could be the issue and how can I fix this? Thank you!
Screenshot can be seen here: https://drive.google.com/file/d/0B8G5zMFj0DQoVmR6SXpFdjN3NGM/view?usp=sharing
I ended up figuring out the issue. You need to apply the transformations in Blender and then flip/recalculate the normals. So select your object, CTRL+A and apply scale and rotation and then enter into edit mode and flip or recalculate your normals. Good luck!
there was a thread like that some days ago
you need to understand that every polygon has a facenormal, and the only direction its usually visible from is the one where the normal is pointing (except you use different shaders, which does not really make sense for something like this, because they need more performance)
you can check your models in blender for this if you press the N-key for the side menu and go to the shading tab
there you click backface culling.
now every polygon that has flipped normals will be invisible
you can also go into edit mode and enable face normals under mesh display
this will shoot out some straight lines from your faces in the directions their normals are pointing.
But that wasn’t the case. With Backface enabled I was seeing everything just fine and with the edit mode and normals as shown in the screenshot I provided. That’s why it was confusing. Backface would hide those faces only AFTER I applied the transformation in Blender. Anyways, I solved the issue.