Artifacts while baking AO.

Rjmozhi

I was baking mesh maps of my model in substance painter while I got this weird artifact along the UV seams in the AO map and normal map(refer image A). (p.s. the UV's are not overlapping and resolution's set to 4k) 

Fabi_G

Hi! Based on those few renders, hard to tell, could be many things.
Ideally share a mesh/part that's displaying the issue (zip and attach to post or host elsewhere), so the issue can be re-produced and the mesh inspected.

Rjmozhi

Hi Fabi_G, I have added a part of the model where the problem persist the most, please feel free to use it.

Fabi_G

Hey! Took a look at the file and the first thing I would note, is that the UVs are not good enough. This loop for example occupies only a few pixels - a bad bake is inevitable:


Second note would be that the model is currently not very optimized. Lots of geometry that doesn't contribute to shape and shading. 

Some general points I would apply to mesh and UVs:
- Aside from additional geometry, use hard edges to control shading. When baking normal maps, split UVs at hard edges
- Straighten and align UVs with pixel grid where it makes sense to minimize aliasing artifacts
- Reuse texture space where applicable, for example mirrored or instanced parts. Offset UVs of those by 1 to avoid issues during baking.
- If something is occluded, you can make it use less texture space. You can have generic patches or trims on your atlas and map UVs of elements to them that don't need a unique texture.

But even if you improved the mesh and UVs, I don't think a unique texture set will get you far with this asset, due to the amount of surface to cover. For real-time, a mid-poly approach with good mesh shading, tiling textures applied and blended and a detail layer on top would be more fitting imo. Certain defining elements can still have a different material ID and use an unique atlas. With enough mesh resolution, you'll be able to bake masks into vertex color, AO for example, if you chose to.

I would look for breakdowns of subjects similar to what you're creating (large, complex, hard-surface vehicles) and take notes on their execution.