zBrush - decimated object got many errors

mobpapst

Hey guys,

i made a brickwall sculpt with plaster background to test sth out and exported the brickwall hp / the plaster hp and my plane lp to xnormal to bake all. But i got some huge problems with my decimated brickwall hp. the hp got 18 stones with a count of 1.6 million. i decimated it first to 10 % but this was way to low and i got bad looking triangles. so i decimated it to 20% with a few less errors and now in the end to 25 % with a count of 400k

But as you can see i got so many problems i see on the decimated one in max and surely on the normal map after the bake:



i pointed only a few errors with the red arrows out but as you can see i got a huge amount of them. i really hope you can help me and point out where the mistake is.

greetz

SuperFranky

It looks like a cage problem to me, I don't think that decimation can cause errors like that. If you don't use a cage, try to use it and see if it changes something. Also, try to use your non-decimated highpoly for baking. Xnormal can handle a lot of polygons, so you don't really need to worry about decimation with it.

mobpapst

Hey there,

i baked now with a cage. i gave my lowpoly plane an edit mesh modifier and an projection modifier and placed the cage. after i exported it as sbm and tryed it again but nothing changes at all. (in xnormal i put the function "use cage" on the lp on)

Bartalon

From the looks of those sharp triangulated discolorations in other areas of your mesh (very center brick and a few other places), you might have decimated your bricks too much.

If your HP has those weird, dark, stretched triangles in it, of course those details are going to bake into your LP. Sometimes Decimation Master can cause surface topology to intersect itself which could be the cause of those sharper, random marks throughout your normal map. I would inspect your high poly at those areas. Maybe shoot for 2, 3, or 4 million points for your decimated bricks, that should bump up the quality of your bake.

Neox

why would you decimate anyways? your renderer surely can handle the polygons. And as for the viewport, you don't need the mesh to be rendered in viewport to be able to bake it.

mobpapst

I done all without decimating my mesh and it works fine. Thanks for all the help so far.

@ Neox: The reason why i want to decimate my mesh is that its easier for me to copy it several times around in the viewport to get on alle outside bricks the same shading the ao is giving to me. but now it works and iam gonna stick along with using the undecimated high poly one.

Thank you guys