SOLVED: Working with a flipped Y channel

Scizz

This has been frustrating me. I baked a normal map in Substance Designer with flipped Y orientation. Then I brought that normal into NDO, and did NOT flip the Y channel, because that would flip it to +Y which is not for UE4.

Now my question is, when I'm adding shapes/bevels, because my Y is negative, does that mean any bevel that I have as "down" is actually "up" and vice-versa? It seems every time I look at my normal map info on my mesh, it seems really off.


Here is the area where I have my bevel. I have it set to slant "UP" but I want my end result to be slanted "DOWN" into the mesh.



And here it is in marmoset, with tangent space set to 3ds Max and have the flip Y channel UNCHECKED because that would flip it back to +Y. If you look at the light near the middle of the image and how it effects the bevel, the light is above the bevel, and I would think, if it was an extrusion instead of an intrusion, there would be a highlight there, not a shadow. So basically this middle part looks like its going INTO the model.

However, if you look at the light to the left, the light is to the left of the bevel. I'm assuming if this was an intrusion, you would also see a shadow along the inside of the bevel, just like the top, however there is a highlight. So basically it looks like that part is extruding OUT of the model.



This just doesn't make any sense IMO. There is a highlight on the top, but a hard shadow directly to the left...

Wiktor

In order to make working with NDO easier you should work with +Y and when you are done and want to put it in UE4 simply flip Y. That's what I usually do at least.

tach

On import, check the calibration profile to be UE4. That'll flip the Y channel of your normal map to +Y for DDO, and it'll flip it back to what you imported originally on export if you check the UE4 profile in the exporter.

Scizz

Ahh okay. So the idea is that if you are importing a normal with a flipped -Y. Check the flip Y option in NDO to bring it to +Y, then work with it, and convert back when all said and done. I will try that and see how it goes, thanks guys! Still, my screenshots above don't make much sense, or is that how it's technically suppose to be?

EDIT: Okay I'm confused again.
Here is my normal. Imported as -Y. Flipped to +Y. Look at the bar on the bottom. It's slant is set to Down, but it even looks up on the normal map.


Here it is on the model. It clearly looks like its extruding. Should I just take the programs word for it, and if I set the slant to down, just believe it is down?


Here it is in UE4. The normal orientation is wrong, but the bar that I was focusing on is now slanted inwards like originally intended. So basically if I import into NDO as a -Y, and set everything I want as slanted inwards, outwards, and vice versa. The end result should be fine. I wish it wasn't like that though. Unless I'm doing something wrong.

Scizz

Okay, started from scratch. Baked my normal map in xnormal with a +Y orientation. Brought it directly into NDO and did not flip any channels. The groove around the grate is at an up slant, but in 3DO appears to be down. The opposite happens when I have it at a down slant.
I flipped the Y channel to -Y and exported into UE4, and everything seems correct. So basically for every detail I need to use the opposite slant regardless if the channel is flipped or not. Is this a bug, or am I just doing something wrong. I don't really have an issue with it being like this, just a tad annoying.

EDIT: Hmmmm, Okay, I think it might depend on the bevel as well. Using a regular square with a default bevel and curve, the slants seem accurate now. So basically when I'm messing with weird details just trial and error.

EDIT EDIT: Seems I was just wasn't thinking clearly. The groove bevel and cone curves were throwing me off. What you guys said above is the right way to do things. What I noticed is that with the groove or cone settings, the slant is determining wether the face of the detail is extruding or not, not the groove itself. Consider this solved. Thanks for the tip guys!

Wiktor

Glad you figured it out!