Can someone please shed some light on Dynamesh for me?

jordank95

Hi guys. Learning zbrush and have some things Im confused about.

When to use dynamesh?

Lets say I make a table in Maya, then bring into zbrush to add detail...why would I need dynamesh?  Why can't I just divide my mesh as many times as I need to add the detail that I need? Isn't dynamesh for sculpting things in zbrush from scratch?

Thanks

Bek

Yeah it's mostly for dynamic (on the fly) retopo when sculpting, so you aren't limited by your starting geo. It's not something you "need" to use.

Scruples

With dynamesh you can sculpt without having to consider topology and the distribution of polygons across your mesh becomes uniform, So you don't have to worry about stretching or whether or not you have enough geometry to sculpt in additional features.

You don't have to use Dynamesh from scratch, you can also use it to get more detail into meshes that aren't subdivision friendly or to do some boolean operations on an existing sculpt.

You're completely changing the topology of your mesh each time so you can't retain any uv's or subdivision information, also you may lose some small details if the Dynamesh resolution isn't high enough.

Joopson

I mostly use it when I have a mesh that looks good in Maya, besides the topology sucking for sculpting-- and I need/want to sculpt it.

Situations where you're happy with the shape (and weren't paying attention to topology), but need to add detail and such. Sometimes I'll bring in a mesh from zbrush, and I find I want to cut a hole out of it after the fact. So I boolean it in Maya, and bring it into zbrush to dynamesh and finalize the details. It maintains all my shapes and lets me smooth transitions. It's my favourite thing about sculpting in Zbrush, and if it weren't for that, I'd probably just sculpt in Maya.

jordank95

interesting. But what if the sole purpose of my mesh in zbrush is to just get a normal map baked out for my low poly? Why should I worry about good topology on the zbrush sculpt? probably stupid question, I know.

So in my case, if I'm adding detail to a table, I can just divide a bunch of times and add my detail and that may be enough without dynameshing? But, if I make any big changes to the table mesh wise, I should then use dynamesh?

Internet Friend

If your base mesh has evenly distributed, clean topo then you can subdivide and sculpt normally no problem. However if you're starting with low poly table with a few big flat polygons for the surface when you subdivide all the density will be in the edges and not enough to sculpt with on the surface. If you Dynamesh you'd get even density everywhere. 

The alternative is to start from a mid poly with good, even topo that you send in for sculpting and also optimize into a low poly. If you want to use creasing, UVs for polygroups or Noisemaker in ZBrush this is a good way to go.