Decimation and normal baking issues.

Vitoria90

Hello. I'm an amateur 3D modeler hoping to make a career in it. I work in Blender and Substance Painter. I spent a lot of my modelling time since I began several years ago focusing entirely on learning how to model, but only in the past year or so began learning about normal baking and optimization for game engines, and on that I've run  into many problems.

So I've done bakes from a high poly to its unsubdivided base before, here's an example of it: https://www.artstation.com/artwork/lVo6Yz


For my next project, though, I wanted have a model with higher detail, something to the level you'd see in a first person shooter's weapon viewmodels.

So I modelled this rifle:

I then subdivided a duplicate of it, added all the necessary support loops to get this 

I then made another duplicate which I subdivided further to get a really high resolution mesh for baking:



I then took the first level of subdivision shown above and used Blender's Decimate modifier to lower its polycount (which I also did on the tank I linked before) and exported it for texturing in Substance Painter:



But in Substance, some parts show terrible artifacting

I honestly don't even know if I'm approaching this whole thing correctly, and I could really use some guidance. I have read the pinned post about normals and normal baking, and I'll be honest I didn't fully understand it, but I seem to have made it work on the tank project, but I'm failing to do so here. Any help will be greatly appreciated.

Ghogiel

Those really thin triangles aren't good. Assuming the UV isn't crap or there is no hard edges breaking at those tris, you might just not have enough pixels simply because the angle of the tri is so acute. Decimating an object like that gun isn't really going to be recomended best practice, you might want to save doing that on some more organic shapes that's aren't so important, like rocks or some statues.

I'd start here in any case

Nothing wrong with what I'm looking at there. Just reroute and remove some loops, add a few here and there for roundness and it'll work out fine.

Vitoria90

Ghogiel said:

Those really thin triangles aren't good. Assuming the UV isn't crap or there is no hard edges breaking at those tris, you might just not have enough pixels simply because the angle of the tri is so acute. Decimating an object like that gun isn't really going to be recomended best practice, you might want to save doing that on some more organic shapes that's aren't so important, like rocks or some statues.

I'd start here in any case

Nothing wrong with what I'm looking at there. Just reroute and remove some loops, add a few here and there for roundness and it'll work out fine.

I'll give it a try, thank you.