High Polygon Model Normal Map Baking?

[kay_Eva]

I'd like a tool to bake very high detail polygon models onto a low poly mesh even if the two models don't share the same UV. This way I can sculpt in voxels. Then export the model. And then project that high poly polygon model's detail onto the retopo object. As opposed to projecting the voxel to the retopo, as for me, the voxel baking loses a good bit of detail. And my primary use of 3d Coat is for real time applications.

Right now voxel baking doesn't appear as accurate as polygon baking...unless I'm doing something wrong.

[Acord]

at the very top: Textures -> Texture Baking Tool

uncheck the box that says "use current lowpoly mesh" and you can select a model to try to bake to by choosing one in the "mesh to receive projected textures" field. I've had pretty good luck with it so far.

[kay_Eva]

at the very top: Textures -> Texture Baking Tool

uncheck the box that says "use current lowpoly mesh" and you can select a model to try to bake to by choosing one in the "mesh to receive projected textures" field. I've had pretty good luck with it so far.

can I see pictures please ^^ of voxels and then of low poly with normal maps?

Can you do this straight from voxels? Does it look accurate?

[lc8b105]

can I see pictures please ^^ of voxels and then of low poly with normal maps?

Can you do this straight from voxels? Does it look accurate?

Why not make a test yourself?

[kay_Eva]

Why not make a test yourself?

that's what I've been doing for the past 2 months. I would never have started asking questions and posting about my concerns if I hadn't already tried it myself about 50 times. I can't get it to work.

[cuffins]

that's what I've been doing for the past 2 months. I would never have started asking questions and posting about my concerns if I hadn't already tried it myself about 50 times. I can't get it to work.

It works...as easy as Acord has described. It also works directly from voxels. But the results depending on the differences between the voxels and your mesh may look...weird...

greez Rene

[kay_Eva]

well, yeah I know it works but I can't get the results to be correct so in that sense it doesn't 'work'

[Acord]

If the normals don't appear correctly in the engine, then this may actually be more an issue with the engine than anything else. For instance, I use the Cube 2 engine which is *very* picky about normal mapping: If something has UVs which are not laid out in an upright manner then the normals always appear wrong.

The workflow I use:

From voxels: quadrangulate to paint

From paint: same as described above

When I dump into paint, I usually go for @ 1/2 million to 1 million tris, 2048^2 texture map, 5 million "apparent" tris, AUTO UV mapping, and it works fairly well. Here's the last thing I worked on:

And the normals baked to the low poly model show up correctly in just about any 3D software I care to try. Here is the low poly bake in the cube 2 engine though, which likes the MD5 format:

And you'll notice that there are definitive seams there. Basically, any uv cluster that isn't straight up or down doesn't seem to work right or bake right.

I'm still experimenting with this stuff myself - the color and spec maps are always spot on, but the normals are giving me fits. Since there's some odd uvmap distortion when 3DC creates a UV map, I've been doing the UVs externally to keep them stable etc.

Today's experiment will be baking out to a world space normal map and converting it to tangent space with xnormal, although I'm pretty sure it's doomed to failure

[Acord]

Nope - it failed. I think I just need to redo the UVs.

Other things I've been thinking of trying:

1.) overlapping edges near UV seams, baking the normal map, and then deleting extra edges and then exporting to a low poly model. Not sure how well that's going to work, but the theory is sound.

2.) "zeroing" the normal map edges by hand. It's a last resort and removes detail near the seams, but it always works. The RGB color for this is 128,128,255 just in case anyone is interested. But I'm trying to do things the hard way here

[kay_Eva]

Have you been able to export using Pick positions from Layer 0 Option? Whenever I do that the model doesn't show up when I import it anywhere.

Eureka! Okay more or less my issues have been *resolved*

I'm not sure how I was supposed to know this but I finally just tried setting Z-bias from 3.00 default to 0, and now I'm getting MUUUUUCH nicer bakes.

You're thinking how obvious that is? Well, I had tried changing it a bunch in teh past I just never got around to a zero, funnily enough.

[Acord]

Have you been able to export using Pick positions from Layer 0 Option? Whenever I do that the model doesn't show up when I import it anywhere.

Eureka! Okay more or less my issues have been *resolved*

I'm not sure how I was supposed to know this but I finally just tried setting Z-bias from 3.00 default to 0, and now I'm getting MUUUUUCH nicer bakes.

You're thinking how obvious that is? Well, I had tried changing it a bunch in teh past I just never got around to a zero, funnily enough.

Hmmm. Yes. I should try that. I thought z-bias was just as a visualization helper...

[akira]

I'm not sure how I was supposed to know this but I finally just tried setting Z-bias from 3.00 default to 0, and now I'm getting MUUUUUCH nicer bakes.

I tried baking with z bias=0 and z bias=10, but the results are the same, no differences.

3.00.08I Simple 32bit

[Acord]

I tried baking with z bias=0 and z bias=10, but the results are the same, no differences.

3.00.08I Simple 32bit

from layer 0? Still haven't tried it - I got reasonably good results laying the uvmap out differently and then manually editing out the seams. It's next up on the list

[kay_Eva]

I tried baking with z bias=0 and z bias=10, but the results are the same, no differences.

3.00.08I Simple 32bit

well, yeah you're right actually, there must be something else that I did, maybe it is all about UV layout the way that Acord is hinting at. Because I'm telling you sometimes I get these weird squares all over my normal map bake and I don't know why. Other times, like the time just now I get really good bakes. I thought it was because of the Z Bias but that must have been just a red herring.

[Acord]

kk...

1.) Lay out UV clusters at 90 degree angles. Turning them in a different angle seems to baffle a few of the engines.

2.) Big seams. Try to put them on natural divides. If your model doesn't have these...

3.) Manually paint over the seams with color 128,128,255. Use a fuzzy enough brush and they aren't real visible.

Today's experiment: Bake to an intermediary model or two with the same UV layout. Most modeling soft will let you subdivide without losing seams - unfortunately, 3DC does not do this with the retopo. UV Seams vanish when it is subdivided. They don't show up as bad when going from high poly to sort of high poly - in theory.

Rinse and repeat in your modeling app until you get to the low poly version.