Help with Zbrush, Dynamesh and a paper thin geometry.

LosRe

Hello, i'm trying to make some stone stairs using 3ds max and Zbrush. I made my low poly model in 3ds max and deleted all the bottom faces since they will be underground and i didn't need them. My intentions were to put my model in Zbrush, make some high poly details and then bake them into the low model. Preety basic stuff i thought.

My problem is that dynamesh completely destroys my mesh since it doesn't like my paper thin geometry. How would you handle this? What i'm doing wrong and how could i fix this. I provide some screens for visual help. Thanks in advance!

musashidan

Dynamesh likes watertight geo. It even tries to automatically fill in holes. You don't need to delete the unseen geo of the highpoly. In fact, in general it's better practice to fill holes of the highpoly for more predictable baking. 

LosRe

I deleted my bottom faces in the low poly model that i will use in the game engine. Should i keep them just for the shake of sculpting?

musashidan

Yes, I know why you deleted them, but for the highpoly you should maintain them. 

LosRe

If low poly doesn't have them and high poly does, isn't this going to mess the baking?

Axi5

LosRe said:

If low poly doesn't have them and high poly does, isn't this going to mess the baking?

No because the Low Poly just won't catch those areas in the rays.

Basically, if the low poly can't see it, it's not a problem. Do as musashidan suggests and fill the holes

musashidan

LosRe said:

If low poly doesn't have them and high poly does, isn't this going to mess the baking?

No, quite the opposite. Not having them there can lead to unpredictable raycasting during baking.

LosRe

Thank you all for your answers! Much appreciated.