Author Topic: Normal Map Baking artifacts (Read 329 times)

Roque Pina · **on:** February 12, 2021, 02:05:37 am

Hi, I just tried my first bake in substance painter and I am having some weird artifacts that I dont know how to solve, so I hope someone could help me out.

I created this high poly mesh in blender, duplicated it and from it, I dissolved some edges and tried to get the tris count down to make this duplicate the low poly mesh.I then uv-unwrapped the low poly and exported both meshes(making sure they were set at the same grid coordinates and one overlapping the other one) as a .fbx with the naming convention( _high and _low).

In substance painter I loaded the _low and set the texture size to be 2048, then went into the baking options, chose to bake normals and AO, imported the _high and set both ray distance to the default. I then baked the maps but it looked so bad I tried baking with a cage, somehow the cage did a better job at baking than the previous try, the thing is that I am getting this black patches at some spots that I don't know the cause and how to fix it.

Also, I am getting the following error: "[Scene 3D] Failed to triangulate polygon (no ear found). Probably not a simple polygon?"

CAGameDEV · **Reply #1 on:** February 12, 2021, 05:02:55 am

If possible please include your low and high poly mesh.

Roque Pina · **Reply #2 on:** February 12, 2021, 02:16:51 pm

Have attached both high and low poly meshes

volker · **Reply #3 on:** February 12, 2021, 03:07:28 pm

You need to increase the spacing of the UVs, there is 0 distance between islands. Also add margin of a couple of pixels (so UVs are not located directly on the border of the UV space).

You probably also want to add a bevel to the additional indentations you have in the highres model, those 90 degree sharp extrusions will not bake well. Also, remove the ngons (polygons with more than 4 sides).

Roque Pina · **Reply #4 on:** February 12, 2021, 05:11:10 pm

So, I increased the distance between islands, gave a margin for the uvs on the uv grid and made a slight bevel on those 90º sharp extrusions on the high res and tried to rebake but it still gives me these artifacts.

CAGameDEV · **Reply #5 on:** February 12, 2021, 05:31:21 pm

Can you upload the mesh with your changes made?

I took a look at your low and high quickly at that spot, you can see they don't match up. Your high is in teal, and low purple. When baking you should try to match them as best you can so the silhouettes are the same.

This is my quick guess to the problem. This holds true all the way through as well.

Roque Pina · **Reply #6 on:** February 12, 2021, 07:16:58 pm

Thank you for taking the time to check out what's going on.
So I guess the problem was duplicating the high poly and then dissolve some edges in order to make a low poly version and it changed the silhouette thus not making both models match even though they are at the same coordinates and overlapping one another

CAGameDEV · **Reply #7 on:** February 12, 2021, 08:27:27 pm

I personally always work High to Low and do manual retopos and my Low is always matching perfectly so as long as I work my edges first then making sure the silhouettes match then filling the rest.

I'm not a fan of duplicating highs and just collapsing edges. With the current retopo tools we have today it honestly takes very little time to retopo hard-surface pieces. Something like this would be maybe 15 minutes of work. Either way there are different workflows and you'll have to pick what works for you the best.

Majority of baking issues I've helped fix are usually from people who do not make a low off their high manually as they forget more adjustments need to be made to match better.

Roque Pina · **Reply #8 on:** February 12, 2021, 08:38:49 pm

This might be asking alot but do you know any retopo addons for blender? Or a personal favourite of yours, I know I will have to pay if I want to expedite my workflow and not spending hours doing something manually.