Sorry, I know the title is a really bad description but it’s hard for me to describe what’s going on so just take a look at the pictures. The first two are of the object in blender. The second 2 are of the object imported into Unity, the first from above, the second from below. Once in Unity, It seems like the object is physically correct based on the outline when I select it, but it obviously looks wrong. If this information helps, I created it in blender by creating the top face as a plane and extruding that downwards along the z-axis. I appreciate any help you guys can give.
Blender will show you a quad from both sides, but Unity only renders one side of a polygon (same as any other game engine, really). That means you need to be aware of which direction your quads are facing.
In Blender you need to turn-on the face-normal overlay. You’ll see that each polygon will have a blue line coming out of one side or the other (That’s the face normal). The side of the polygon that has the blue line is the side that Unity will render. So if it’s on the wrong side, select the quad and flip the normal.
If you need to render both sides, it’s possible to use a custom 2-sided shader. otherwise you’ll need to go into Blender and make a separate quad for each side.
I see what you mean with the normals. However, I tried creating something similar with only scaled cubes and found that some cubes had “normal” normals and some had the inverted ones that caused them not to be rendered in Unity. Is there anything I can do to prevent the normals from inverting in the first place? Also, thank you for your help.
I think if you create a regular primative cube in Blender then the normals should be pointing outward, unless you do some sort of negative transform on it. Also, if you are making a closed object, there’s a single-button fix (it’s labeled “recalculate normals” or something like that)
Normals are subjective, though, so it’s not necessarily something that Blender can always figure out. If I were making the inside of a room, for example, then I might want my normals to point inward instead of out.
@WinkingSteve Blender has option to show backfaces. I don’t think you need much else to fix orientation if it’s just a few faces? Rotate around your model and flip the wrong direction facing faces.
If scaled cube had normals to wrong direction, you probably scaled it to negative size and then reset the transforms (used Apply all transforms) and got left with an inverted cube. Scaling alone won’t flip faces, it only happens when you apply the negative transform.
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