xNormal Map Problem - Intersecting polygons when trying to bake multiple objects

tapsteady

Hello! I'm an experienced Maya/ZBrush artist, but new to the awesome, can't believe I just discovered it, xNormal + dDo workflow. Probably missing something that's really simple... or what I'm trying to do just isn't possible.

Here's the problem... *shrug* I modeled a shield with many different parts (wooden planks, metal rim, bolts, etc.)

I have my LP Mesh:


HP Polypainted Mesh:


UVs of LP Mesh:


After merging the objects in Maya & ZBrush, I export to OBJs and also create a cage from my LP mesh to be slightly larger than my HP mesh. When I bake out any map from xNormal, I get overlapping pieces on any map I try to bake.

It's easier to see the problem on the normal and vertex color maps. The pink bolts on the left have outlines on the blue metal rim. Same goes for the purple arrowheads on the orange wood planks.

Normal, Occ, and Vertex Color maps


I'm sure there's a stupid easy solution to this. I've been trying to wrap my head around this for days playing with settings in xNormal. Do I have to bake these normals separately? For each piece?????

Thanks in advance!

m4dcow

Normally I would tell you to explode the mesh ie: offset each of the high poly and low poly counterparts so you can bake a clean normal map, vertex color map etc...

But TBH I think you should reconsider your low poly and make it one piece, since nothing really deviates too much from the shield shape.

tapsteady

So if I had a more complex model, i'd bake them separately and then combine the normal/vertex maps in photoshop? Guess there's no other choice because of the way it's calculated. I'm assuming AOcc should still be baked together though, right?

But in this case just start from scratch and make the wooden planks / center piece all made from a single cylinder?

Thanks m4dcow

m4dcow

tapsteady wrote: »

So if I had a more complex model, i'd bake them separately and then combine the normal/vertex maps in photoshop? Guess there's no other choice because of the way it's calculated. I'm assuming AOcc should still be baked together though, right?

But in this case just start from scratch and make the wooden planks / center piece all made from a single cylinder?

Thanks m4dcow

Well would could bake separately like you say, but this would require combining all the bakes in photoshop every time you need to re bake. I think the Substance Designer 5's baking system is adding something I suspect to automate this sort of thing, ie: combine separate bakes and hopefully when xNormal 4 is released it has a solution to make this easier also.

Exploding is like those technical diagrams of machinery that show how everything fits together, so you don't have issues with clipping projections. Benefit is you don't have to combine maps in photoshop after baking.

I also believe Max has something with material ids where if you assign a particular material id to a corresponding high and low poly pair, it won't pickup from another corresponding set. Not too sure how it works under the hood, plus I use Maya so I don't really have much experience with it.


And yes the AO would still be baked with all the meshes together, in some more complex cases with intersecting geometry, it requires combining a high poly bake with a low poly.

Quack!

I agree with madcow's first thought, just model the low as 1 piece, watertight. You will get a better bake and increase your texel density by a metric ton.

You should rarely/never combine multiple bakes in photoshop for a single object. That is bad practice.

tapsteady

@m4dcow I'll explode the mesh and check out SD5 then! Awesome.

Even if I model as a single piece, I'll still have to explode the mesh because of the handles on the back. (didn't post it earlier)


Will let you guys know how it turns out later tonight

Quack!

Yup exploding is inevitable. In max you can tell it to bake based on material IDs which makes exploding obsolete. I don't know if you can do something similar in xnormal.

m4dcow

Substance designer 5 isn't out till next week Thursday, but I only mentioned the baker because it makes this process easier.

SuperFranky

Exploding saved my life