Sharp-edged sculpties in ZBrush?

I'm having success creating organic shapes for sculpties in ZBrush. The program is really ideal for pushing clay around to make fruit, pillows, rocks, and the like. But I'm having more trouble using it to make things that have some hard edges, like furniture. I know I could use SL tools to make the hard-edged prims, but I was hoping to use sculpties to keep the prim count down.

E.g., I had dreams of making a bedframe as one prim, using a Cube3D, hollowing it, and detailing the two head boards. Is that unrealistic? If so, I suppose I could make a frame as 1 prim and 2 more prims for headboards. In that case, I suppose the headboard might have three square edges and one curvy, finely-detailed side. Is it asking too much of a low-poly ZBrush Cube3D to make such a thing as one prim? Or should I make a simple square prim in SL and add a curvy "top" to the headboard using ZBrush?

Also, just how does one push a Cube3D around in ZBrush without losing the hard edges? Using the Deformation pallette, I can do some flattening, but it only lets me go so far. Ordinarily I'd use zSpheres and/or edge loops for this sort of thing, but sculpties require a constant number of polys, so the preferred workflow seems to be to fire up your 3D primitive and just push it around.

Anyone have advice on all this?

yea, use something else. But seriously, I am curious as to what the experienced ZBrush users are going to say because I too have the same issue with ZBrush, so I use wings instead for anything that I want that isnt organic in nature, then I can texture it in Zbrush if I want.

I would agree with Nectere. If you want to do a lot of hard-edged, geometric type modeling then zBrush may not be the best choice. Of course most of my experimenting with zBrush has been to make soft organic shapes - but that really is its strong point.

I think that the best way to get hard edges would be to use a very crisp mask. When you use CTRL and drag out a box to create a mask the edges of the mask is nice and sharp. Yuu might also experiment with some custom Alpha brushes that have sharp edges.

There is also the Crease option, but that involves adding faces and subdividing, so that is probably a no-go for sculpties.

Yeah, I had a feeling you guys would say that. Maybe it's time to dust off my rusty Max skills -- or just use SL itself for rectangular prims.

I thought of Crease, but as you say it adds geometry. Likewise with edge loops. As for masking, I have trouble getting a clean hard-edged mask with the Cube3D. I use CTRL/box as you suggest, and I set my focal to perfectly sharp and my draw size to 1, but I still get overlap. I might play with the Initialize tools more. The 'coverage' tool for the Sphere3D does a very nice clean slice, like an apple core.

SL itself can make perfectly good rectangular prims. It's just not so great for rounding the edges. E.g., most of a mattress should have a pretty sharp edge, but the corners should be rounded. Max is good for that sort of thing. I imagine Maya is too, but I'm not a Mayan. But ZBrush is so much more fun to use than any of them.

If anyone else has advice, please jump in.

Get your mom to make your bed!




Just kidding!

The 'Crease' option is the answer.

If I were to make a bed then I would start with a 8x9 or 16x17 object to create the basic shape and then I'd apply a 'Crease' along the edges that I wish to preserve before hitting 'Divide' many times in order to get it into a state for detailing.

A good tip:

Low resolution 8x9 or 16x17 objects are key to modeling in ZBrush. This is the reason why subdivision surfaces were invented. The workflow is to start with a very low detailed model that can be created rapidly and then add the details later.

The problem with the above modeling method is that most of the converters are quite strict on the vertex order of the imported .obj file. So this is why I personally use the Maya converter. Maya's converter doesn't map the vertices directly, instead it uses the UV Map of an object to help map the vertices.

But there's hope:

I plan on releasing a new version of my converter when LL fixes the lossless sculpty bug. My new converter will use the UV Map to help work out the order of vertices and yet will still map those vertices directly. So we'll get the best of both worlds. YAY!

Thanks for your reply, 2K. Yep, left to my own devices, I always prefer to start with a low-poly mesh in ZBrush. In fact, I prefer zSpheres to the 3D primitives. Either way, I love how ZBrush lets you switch freely between your low-poly mesh and your higher-poly versions of it. That way you can make big changes on the low-poly and small changes on the high-poly.

Anyway, your suggested work flow makes sense to me -- I just assumed that starting with a lower-poly model and subdividing would create problems for the converter. I guess I assumed right! But it sounds like there's hope. I'll root for LL to fix that bug.

In the meantime, I'll keep fussing with the 3D primitives and the Initialize and Deformation pallettes.

Great news! Looking forward to this new version of your converter, 2k

I was able to get some decent sharp edges using a couple of the other 3D primitives in ZBrush, such as the cube and the spherinder. Using the deformation pallette, I was able to flatten and flip the things enough to make them useful. The main problem is that those prims establish funky "poles," so that you get too many polys where you don't need them and not enough where you do.

The other problem is that I have had trouble getting the converter to recognize them. I'll fuss with them more.

Glad to hear that your experiments are producing results, Ricky. I feel your pain with the vertex arrangement at the poles of the objects. Always a pain to arrange those bits so that they don't cause too much trouble. It is possible to sort of squish the faces around a bit to put more faces where you need em, but that might be a bit harder to do when you're trying to create clean, geometric shapes.

I've finished my tutorial on using zBrush primitives for Sculpties. Might be some info in there that is helpful for ya, although it sounds like you have it worked out for yourself:

http://www.shiny-life.com/2008/05/19/using-zbrush-primitives-for-sculpted-prims/

The most important thing to keep in mind is to always set the hdivide to 32 and the vdivide to 33. That is the only arrangement that will work with 2k's SculptMaker converter. You also have to convert he initial primitive shapes to a PolyMesh with the Make PolyMesh3D button. You can export the primitive as an .obj, but it won't convert correctly unless it is a polymesh.

Thanks, Vlad. I'll have a look at your tutorial. I wouldn't be doing this had I not seen your first set of three videos.

Using 32/33 does indeed seem to work with most of the 3D prims. The one exception seems to be the spherelinder, which is a sort of hybrid sphere/cylinder. It will only accept the values 32/35, which results in too many polys. It's not that big a deal, but it is a sort of cool prim, so it's too bad.

Yeah, I try to move the "poles" around so that the polys are more useful, but it sure would be nice if ZBrush included a cube and sphere prim that had no "poles" at all. I'm sure there's some good technical reason why it doesn't.

Yep, I know to convert to polymesh. I've ZBrushed long enough that its rather pleasant quirks are almost second nature to me. Draw the tool; immediately hit T or be doomed (DOOMED!); convert to polymesh or be spammed; don't hit G til you're really ready to paint.

I've been able to use the spherinder with 32x33. it doesn't like it when you type in the 33, but when you use the slider it will accept that setting. dunno why.

Vlad do you offer a way to save the tut to disk for watching without having to go through all the loading stalls by blip? (and offline)

I've noticed a slowdown with my Blip.tv hosted videos this week - though it was just me If it continues I will have to find a new place to host my vids. Never had a single problem with Blip before.

You can donwload that original .mov files from Blip, but they are kind of hidden away. IF you click the little book icon on the blip player below my vids, then click "Read more about this post on Blip" you'll get to the page for the video. Then look at the right side of the page for the Files section, click that and you can see the link to the original Quicktime file.

I always forget to post that link on my blog articles, but I'll try to remember in the future. The direct link to the tutorial about zbrush primitives is:

http://blip.tv/file/get/VladBjornson-UsingZBrushPrimitivesForSculptedPrimsPart1281.mov

http://blip.tv/file/get/VladBjornson-UsingZBrushPrimitivesForSculptedPrimsPart2469.mov

Ohhh, thanks for the tip on the sphereinder. Off to try it now!