ZBrushCentral

HD Geometry: can someone explain me ?

ZBrush Usage Questions
#1

Hello friends !

Today I was reading more about the HD Geometry in zb3.
But I am a little bit confused about the purpose of this feature.

Does it mean, if my computer can’t handle more than (as instance) 4 Million Polys on one mesh, I can turn on HD Geometry, and my mesh will be pumpe up to about 1 Billion Polys ? But in fact it’s nor really 1 Billion Polys, because it’s like a fake ? Or like a proxy mesh ?

Hmm, I really don’t know at the moment, can’t imagine about that feature and I can’t figure out the purpose for that.

Thank you so much for every little help,
capu

#2

ive been playing with it today and it is really good. the only problem right now is that you cant export the high res detail in a displacement map or normal map yet but this will come soon apparently.

here’s how it works…

you have your standard subdivision like in ZB2. go up to a comfortable amount that your computer can handle (actually you dont need to go that high and in the little play ive had it seems to be faster when the normal subd level takes the model to about 1 million or less).

When you are happy with youre scult and want to do really fine stuff you go into HD Geometry mode. This allows you to add further levels of subD on top of the standard one but doesnt actually apply it straight away (and crash zbrush or get mem error messages). once you have decided how many polys you want (up to a billion which is defo possible cos ive done it on my 2gb ram 2.16 core duo laptop), you use move your mouse over the area you want to sculpt and ZB gives you an area around the mouse to sculpt and offloads the rest of the model out of ram (i assume to disk/virtual memory). the area that it gives you is quite large and gets smaller the more polys the HD geometry you have whacked it up to. with the model set to 32 million it enters the HDsculpt mode pretty damn fast and when it is at say 200 million it is still fast. I’m really impressed and i dont ever see the need for more than 60 million polys (8000 x 8000 texture maps have 64 million pixels).

when you hit the ‘a’ key again to go out of the sculpt mode, it reloads the rest of the model and redisplays the model at the highest standard subD level. If you want to see the model rendered with all the HD detail, you have to hit the HD sculpt button with the mouse in the tool section (as opposed to hitting the ‘a’ key and it will build up a render (that takes a few seconds).

like i said you still cant export disp maps of the HD stuff yet but that it is in the works for a point release in the near future according to the post in the main forum announcing the release.

Hope that helps.

Dan
3d Artist
www.The-mill.com

#3

Does anyone have any news whether or not normal maps can be generated from HD geometry. I am assuming that is still not possible as well (Zmapper 3?), but it would be nice to get official word.

Similarly, Would there be a way to “collapse” HD levels down into SDiv levels so that for the time being, if your system could handle it, that you could generate these maps?

#4

Heh, you should REALLY read previous post :wink:

#5

okay thank you, I think I could understand. But if you can’t export a displcament ap I think I will not need it yet.

however, if that feature will work with displacement map - wow, that’s pretty nice.

thx for the info,
capu