[Bug] Retopo mesh artifacts on textures

[Grimmy]

Hi all, no matter what settings I try, I can't get rid of these artifacts when I bake my texture onto my new retopo mesh.(Merge with NM(Per Pixel))

Any ideas?

Thanks

[AbnRanger]

Without knowing what version you are using, and without some view of the screen (where we can see the mesh, the UV layout and the settings you have....we are blindfolded as it were. Can you click ALT + SHIFT + S in the Retopo Room with your "baking scan settings" (Retopo menu) panel?

[Carlosan]

try smooth mesh off

[Grimmy]

Oddly enough, I turned off Autosmooth and the problem went away.

?

Is that the same as Smooth mesh=off?

Edited June 25, 2013 by Grimmy

[alvordr]

I almost never change anything in the final dialogue sending a retopo to the paint room. The only thing I check is "Don't snap subdivision vertices to the surface" and perhaps adjust the texture size and/or UV-set name. If I have manually UV'd the model I would change the UV-mapping type, as well.

[TimmyZDesign]

I have never fully understood what the purpose of Autosmoothing Groups is. Can someone explain it to me?

A theory that I have: In 3DS max smoothing groups are used to make edges look hard or soft. The user selects edges and chooses to make them hard, then chooses other edges and chooses to make them look soft. In Maya there is a similar functionality but it isn't referred to as "smoothing groups", instead the user selects edges and then chooses to make the normals on those edges hard or soft. My guess is that the Autosmoothing Groups in 3D-Coat is intended to do this process for you. You enter a value for the angle (for example 35 degrees), and 3D-Coat scans the model. Wherever 3D-Coat finds an edge between two polygons which has an angle less than 35 degrees, then it makes the normals of that edge appear smooth. If the angle is greater than 35 degrees, then it makes the normals of that edge look hard. Therefore it is called Autosmoothing Groups because it automatically makes edges look hard or soft based on the angle that you choose. Although this is my theory, and I think it makes sense, I have not gotten baking results that support this theory...therefore, maybe my theory is incorrect? Does anybody really know what is going on with "Autosmoothing Groups"?

Edited June 26, 2013 by TimmyZDesign

[digman]

You are correct in your theory which is very easy to prove.

Import into the paint room the default cube using PPP with auto-smoothing off and then with auto-smoothing set to the default 30 degrees.

The first cube imports into the paint room with rounded edges and the second with sharp edges.

The feature works really well on importing hard surface polygon objects into the paint room for normal map or texture work.

Now if your are baking from the retopo room a sculpted voxel object with some sharp edges the normal map will take care of the sharp edges for you.

It seems if you use auto-smoothing set to a degree then this messes up the appearance of your normal map.

You can use the Merge patch (bake) for per-pixel with no normal map and set the auto-smoothing to a degree and it will correctly merge the retopo model. Of course there will be no normal map.

That is a workflow decision. Example, you create a hard surface object in the voxel room but want to create your normal map directly in the paint room. Then you would use the auto-smoothing setting so your hard edge voxel model would not be rounded off at the edges.

[TimmyZDesign]

@Digman: Thanks for helping to explain this to me. I tried importing the default cube with the different settings that you suggested and I finally saw the autosmoothing groups working correctly! Thank you for that!

But in the second paragraph of your post you say that using auto-smoothing on a sculpted hard surface object with "some" sharp edges will mess up the normal map. This is the problem that I have had in the past. I was hoping that the sharp edges would be made to look sharp in the normal map, and the smoother edges would be made to look smooth (based on the degree setting), but it doesn't seem to work correctly in that way. That's why I kind of gave up on the autosmoothing groups because it seemed as though it was better to always leave it unchecked (in order to avoid the bad normal maps).

In the last paragraph of your post you say that you can merge to the paint room without a normal map, but I don't think I would ever want to do that...doesn't seem like there would be any point to that if my main purpose for the normal map is to bake high poly details down to a low poly model.

[Tony Nemo]

Many hard-surface models (as opposed to organic shapes) don't have a lot of surface detail and being 'smooth', can get all the definition they initially need from the mesh itself.