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I have been looking at different tutorials and even other postings on Stack Overflow to try and figure out how to bake detail from a high-poly model into a low-poly model. I have provided screenshots of both models: enter image description here

I have UV unwrapped my low-poly object. I have also created a new texture image, linked it to a normal map which is attached to the low poly-object. I have made sure before baking that both objects are shaded-smooth. enter image description here enter image description here

I have set my bake value in the following manner. The models are on top of each other when I try to bake, I just separated them in the above image to show the difference between the model detail.

enter image description here

When I bake, it looks like it creates a good normal however, the model does not seem to get the same level of detail (not smooth). Is there an issue in my setup? Or to get the smoothness of the high-poly model, do I need to do something additional?

enter image description here

File:

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  • $\begingroup$ Did you try "recalculate normals" in the low poly mesh (Edit mode, select All, Shift N)? $\endgroup$ Feb 26 at 6:47
  • $\begingroup$ @joshsanfelici , Yes, I have made sure all normals are facing the correct direction. $\endgroup$
    – mjbelanic
    Feb 26 at 22:23
  • $\begingroup$ Hello, it's not clear what kind of details you're trying to bake, the high-poly has no details actually, also the low-poly has a shape that is quite different, and last thing, the baking Extrusion value is too high (0.5 units), not sure why you want such a high extrusion $\endgroup$
    – moonboots
    Feb 27 at 12:42
  • $\begingroup$ @moonboots, What I'm trying to get is the smoothness of the front front and bend in the boards. I also don't understand why the board is concaving it the center. $\endgroup$
    – mjbelanic
    Feb 27 at 16:25
  • $\begingroup$ Do you mean that you're trying to bake the low-poly onto the high-poly object? $\endgroup$
    – moonboots
    Feb 27 at 16:32

1 Answer 1

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So this is what we see when we open up the file:

enter image description here

  1. First thing, of big note: the low poly shape doesn't agree very closely with the low poly, for some reason both objects are keyframed, and the low poly and the high poly intersect.

  2. The target normal map is connected with the current output, which will create a bake loop. We're baking the difference between the two objects' normals. We don't want to connect any normal map until after the bake.

  3. The normal map node is using a strength of 10.0, which is insane. This is a value where reasonable values lie between 0 and 1.

  4. We're baking selected to active, and using a very large ray extrusion-- 0.5 meters of extrusion, when our object is only about 0.15 meters tall. And we have a max ray distance of 0.5, which is totally unnecessary.

We see some things that are good too. No overlap on the UV map, and there's only a single UV map, so no room for confusion there.

Let's fix the first three problems. We'll delete all keyframes on the objects (because keyframes can only cause us problems) and reposition it to more closely match. We'll disconnect our normal map. And even though it doesn't matter yet, we'll set the normal map strength to the base 1.0:

enter image description here

Now, let's look at the final problem. When we bake, our low poly will shoot out rays in a direction opposite the surface normal, and read the high poly at the first place that gets hit. Here, the low poly is inside the high poly someplaces, so the place that gets hit is sometimes going to be the wrong side of the high poly. That's why we use ray extrusion: to start our rays further out than they actually are. We don't usually want to use max ray distance at all.

It can be difficult to visualize how much ray extrusion we want. What I do, rather than use ray extrusion (I will set both it and max ray distance to 0) is just use a temporary displace modifier on my low poly, which does the exact same thing:

enter image description here

So that's a displacement of 0.5: that's where it's shooting rays from! And we can see that with that much extrusion, we've got overlap, self-intersection. Let's tune that extrusion to the bare minimum we need to fully enclose the high poly:

enter image description here

One tenth as much. Unfortunately, even with that, we have overlap in the low poly, because of the close loops. But we can't use any less, because of the strong disagreement at the nose. So let's edit the low poly to spread those loops a bit:

enter image description here

Better. Not ideal, since I didn't do anything to the nose, but this is still something we can work with. We'll bake now. Then, I'll disable the displacement modifier and re-connect the normal map and see what we get, side by side with the high poly using the same BSDF:

enter image description here

Just about a thousand times better! It's still not great, mostly at the nose, where we have that strong disagreement between the low poly and high poly.

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