ZBrushCentral

Dynamesh Mouth issues

ZBrush Usage Questions
#1

I have sculpted a full human figure with Dynamesh and now want to sculpt the mouth. My issue is that I have no honest idea how to go about this with dynamesh… When I try forming an inner mouth cavity with the move tool, then try moving the lips together, dynamesh will try merging the lips together when they get too close.

For that matter, even when I am not trying to create a mouth cavity and I just want to make a nice detailed part between my closed lips, dynamesh will mess up any new detail I create as soon as I actively remesh.

It’s really annoying. In your guy’s opinion, what might be the best route for tackling mouths while working with Dynamesh?

Thank you very much!

#2
  1. Turn up the DM resolution slider.

A small gap between lips is a fine detail. The finer the detail, the more resolution DM needs to hold that shape. Keep in mind there is a detail limit for DM working with a mesh directly. It’s a tool designed for shaping form in low to medium resolution meshes. Beyond that, detail will be lost, and you have to zbrush as normal with levels of subdivision for fine detail. You can then Freeze those high subD levels, and use DM to remesh the base level mesh, and unfreeze the higher levels, which will re project that high level detail.

If you absolutely can’t summon enough resolution to capture the detail, you can try increasing the size of the object in the ZB worldspace, through transpose or deformation scaling, which will sometimes increase the resolution and accuracy.

  1. Increase the gap between the lips.

If the lips are touching , DM will read them as a continuous surface no matter what. The wider the gap, the less resolution DM will need to keep that gap.

I just tested this on the demo soldier tool. I fashioned a cavity (again, make it spacious enough that it can be distinguished easily), and two crude lips that I closed most, but not all of the way. Dynamesh was able to retain this detail with the resolution slider at the 200+ range. So it is possible.

#3

Thank you very much for your response! I really didn’t know that DynaMesh was mainly for Lower to mid ranged detail, but now knowing that will help improve my workflow.

Though your solution that you provided would work to a certain degree, however I slept on it and thought of an idea that I would like your opinion on… Maybe it would be a better idea to just put the lower lip and lower part of the jaw on one layer, then on another layer have the upper lip and everything else… I could then sculpt the inner mouth from a different subtool on a different layer…

That way, my lower lip would be on one layer, the upper lip on another layer, and the inner mouth on yet another layer. It seems that at this point, I could open and close the mouth and define the inner mouth cavity very easily. Also, If I ever for some reason needed to Dynamesh the main body again, Since the lower lip would be on a separate layer, dynamesh wouldn’t have any “Accidents” with connecting the lower with the upper.

Oh… And one last thing I noticed… It seems Dynamesh’s strong point is to make major changes to a structure without being limited by a polycount and polystretching. At fine levels of detail, I suppose it’s best to just not use Dynamesh at all. Because even if you do need to make a major structural change using dynamesh while you have already achieved a high level of detail, as soon as you unfreeze your higher detail levels to begin baking them to the dynamesh… the baking process sometimes will ruin whatever change you made, depending on how drastic it was.

Anyways, your opinion would be greatly appreciated! As I’m sure you can tell, I’m very new to Zbrush, and am learning all of the old stuff in addition to the R2 stuff.

Thanks~

#4

Dynameshing a mesh directly is best when working with form at low to mid level resolution. In other words, it’s for making bodies and rough surface detail, but not fine surface detail like pores and wrinkles. The latter is likely to be lost to some degree.

Turning on projection in the DM menu will ensure you retain pretty much all your detail if you are working from one dynamesh to the next, as long as you’re staying at the mesh resolutions DM works at, which is generally under a million polygons. But if dynameshing a high poly mesh into dynamesh, loss in unavoidable…a 300k mesh will not hold 5 million polygons worth of detail.

However, you can work with dynamesh indirectly through freezing subD levels. This basically automates the traditional remesh and projection methods in the subtool menu for projecting high subdivision level detail, while you use dynamesh to make changes to the base mesh. You shouldn’t really lose any surface detail here, as that type of projection works great for surface detail, but youre always going to run into issues when you do something like put a tentacle where a face used to be, and try to project that detail. Radical changes in form will always be a bit messy, and require some touch up.

None of this should really matter for your problem. Like I said, I made a functioning mouth just fine on the demo soldier, and didn’t have to turn the rez slider up much at all. Just make sure to give DM some space to work with between the lips.

Layers can be great for shaping various facial expressions, although you should know layers do not work with Dynamesh. You’d want to get your mesh made to the point where you’re ready to start zbrushing as normal before you start using layers.

I wonder though if when you say “putting the bottom lip on another layer” , you actually mean making it a separate subtool. In which case no, the face should all be the same subtool, otherwise they become separate meshes, split apart, and unable to be sculpted on at the same time.

You may, however, want to put the lips into separate polygroups within the same subtool. This will help with such auto-masking features as “Mask by Polygroups”, and “toplogical masking” that can be found in the Brush>Auto Masking menu, and may be helpful when sculpting mouth expressions.

#5

Thank you very much for taking the time to answer my questions. I actually was talking about subtools and mistaking them for layers. I looked up and learned what layers are and realized how useful and easy they make things. So I will definitely utilize layers in the creation and storing of my facial expressions.

One problem I continue to run into however deals with Polygroups…

Polygroups are a neat feature, but is there any way to view all of my current polygroups in a list?

Once again thank you so much, I know exactly what I’m going to do now as far as creating a working mouth.

#6

I don’t believe so, but if you turn on polyframe view, you can see all of your polygroups color coded.

#7

Ah okay! that works too. Thank you so much, you have been an amazing help.