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DavidF

Base mesh quality not good for useful smoothing

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Hi everybody!! 

 

I wanted to share some thoughts about how to improve sculpting quality for the artist in 3d-coat. As a 3d-artist myself, and as I've seen from many 3d sculptors, smoothing is one of the most valuable tools, in fact, many many things can be done only by drawing, moving, and smoothing. I've seen the latest updates to brushing, which are very good!! However, I think we still lack a good smoothing, and not because the algorithm is bad, it is because in 3d-coat the base mesh that comes from voxels comes in bad quality. Here is an example:

 

4e3r.jpg

 

I think this should be given attention, perhaps by having the posibility of "resampling in projected dense quads" or something like that directly in the viewport. I think most sculptors spend at least 30% of their strokes on smoothing... however, right know, this can be a little unreliable in 3d-coat.

 

On a broader thought, I've seen the new ability to "loop subdivide" that, with a descent base mesh and the ability to go up and down subdivision levels, may be all 3d-coat needs to be "full featured" in the sense that you could do all your sketching and precise sculpting here. I think that if one enters subdivision levels mode, options like live clay and voxels should be greyed out, and then users should be able to break this whenever they feel like it (for example if they want to sketch again, or add very very tiny detail with live clay). Subdivision levels are very useful for the same "smoothing" reasons as of the base mesh quality, cause you can always "smooth back" to a clean surface and produce nice and soft results at any level of detail... And, lastly, you can of course smooth big details in a level while maintaining the smaller ones in a higher subdiv level. 

 

However, this "broader thought" I know is a bigger feature that cannot be implemented in a day or something, however I do feel like we can improve base mesh quality by having the option to "resample" in a quad/even manner. 

 

What do you guys thing?

 

Side note:

there is no problem with base mesh in voxels, of course, cause it changes all the time...

 

 

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Edit:  I remove the link as somehow the page and post number got changed...

 

This is just to help your current problem and is not meant to reflect upon your ideas or suggestion...

 

And are you talking about voxel mode or surface mode, The below is for surface mode which I think you are discussing..

 

Use the Smooth all tool entering suface mode. Select tangent smoothing and set your smoothing degree, test different smoothing degrees to see what is the one that works best for your model.

 

This will help you on getting your voxel mesh ready for surface mode sculpting and smoothing...  This was confirmed by Andrew, We also are asking him to give the user an option of doing this when entering surface mode for the first time. Maybe he can improve the tangent smoothing to give us an even better surface mode mesh.

 

In the top menu for your shift key control, choose relax, now when you smooth, you can hold down the shift key and relax the mesh, then keep smoothing.

Plus I made some of my own smoothing brushes. Artman's presets have them as well. 

 

LC and surface mode still create alittle too much surface noise, which one must remove. I hope Raul when he gets back to Kiev, has time to optimized the routine better.

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When you are in surface mode, if you look above the viewport, there are various SHIFT options (used while holding down the SHIFT key and brushing at the same time). If you are having trouble smoothing a part of your mesh to your liking, you can switch to using one of those options to fix your mesh so that it will smooth nicely. Several of the options there actually and completely change the topology to make it more useable. The great thing is that the topology will only be changed in the spots where you brush while holding the SHIFT key down. All of the other parts will remain exactly the same. Additionally you can change the topology with the Reconstruct tool. Paint the area that is troubling you, and click on Apply. The topology there will be fixed up nicely, and it will be easier to smooth it. The CleanClay brush sort of does the same thing, but is slightly different. Try playing with those SHIFT options and you will see the amazing power of 3D-Coat. No other sculpting software that I know of has these amazing abilities.

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digman:

 

Thanks. I tried it and it actually improves the quality of the base mesh, however it does smooth out a little too much the model and there is still some unevenness in triangle distribution. Call me exageratted but I believe every sculptor could benefit from a fully even quad mesh. The trick you mention actually helps me a lot for now but a full conversion to projected quads I think could be even better. That with subdivision levels and topology "locking" would make a great addition... 

 

TimmiZ:

 

Oh god! I actually didn't know about cntrl+shift smoothing. Does quite a good trick. :D

 

Still, what I was proposing here is more like a different workflow... Good base mesh + topology locking with subdivision. I don't know, many artists are comfortable with this and there are many cases that it's really useful, like clothing, control over different detail levels, etc...

Edited by DavidF

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I believe the Voxel sculpting environment is still superior and preferable for many sculpting applications.  I think what is missing in that regard is a consistent workflow where the user progresses from a low resolution Voxel mesh to a higher resolution mesh.

 

If this workflow is adhered to, Voxel smoothing is quite predictable and controllable.  At lower resolutions, Shift Smoothing with the first Alpha from the Panel (far right) can have both a subtle and an extreme effect - which, when used with the Fill tool, can dramatically alter or subtly alter a Voxel sculpt.

 

I've never had any problems with the kind of uneven effects or lack of control associated with using the Surface or LiveClay versions of these functions.

 

As far as performance goes, Voxels are quite practical even on low powered hardware (laptops with no dedicated graphics card - even AMD hardware).

 

Surface and LiveClay brushes are much more a "work in progress" than are the much older and mature Voxel equivalents.  Especially since Raul cannot be constantly present in Ukraine with Andrew.  These tools need more time and attention to become as mature as the Voxel sculpting tools are.

 

Many users have always tried to adapt 3D-Coat to workflows with which they are more familiar (which may hinder these users when starting with 3D-Coat) - like the Zbrush methodology, for example.  Zbrush has always relied on ACTUAL geometry to produce coarse shapes and fine details - whereas 3D-Coat has employed the very different method of producing medium to fine detail by means of displacement (maps).  In 3D-Coat it is not necessary to produce fine detail with tools that modify actual geometric density.  Zbrush has never had this real-time methodology. 

 

Yet, we see and hear a continual stream of questions that demonstrate the mindset of users:  Detail must be produced by means of actual geometry - nothing else will do.

 

In Zbrush, for example, detail must be translated into maps before a sculpture can be truly practical.  This happens "after the fact" mainly with plug-ins.

 

In 3D-Coat, this same process happens in real time - so that the user can see the effect of these maps while they work.  Much more practical - in the long run, than a "less than real time" alternative.

 

3D-Coat's implementation of, firstly Surface Mode, and later LiveClay - was and is a reaction to the needs of users to reduce dependence on high powered hardware setups which feature dedicated graphics hardware (desktop computers).  The design of these new sculpting systems was intended to mimic - to the best of their abilities, the functions already present in Voxel Mode.  And, since then, working with Voxels has become increasingly more efficient - giving good performance on similar low powered systems.

 

Surface and LiveClay are still "experimental" systems.  Not perfected and subject to flaws and workflow interruptions.

 

I encourage everyone to revisit the Voxel workspace and the paradigm of working from very low to medium high resolutions - and moving to the Paint Room for the production of fine detail.  

 

High density meshes - whether they are triangular or quadrangle-based - are not very practical for most of the applications of models produced in either 3D-Coat or applications like Zbrush.  Good thing to keep in mind and to put methodologies in proper perspective.

 

 

Greg Smith

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Psmith, 

 

I understand what you mean in general, however I don't see why implementing subdivision surface sculpting while "locking" geometry would be a bad thing. There can be a thousand reasons why a program should do this or that, but I think in this case it's also very important that artists can choose between modes that in many cases may be more comfortable with. I've done lots of voxel sculpting, and although you say it is very good performance, it isn't the case on full high detailed characters, in fact, it's very hard to work. On the other hand, voxel's freedom can also be a problem when you are in the "finishing touches". For example, what if you have lots of muscles in your character, and you want to inflate them so much that they almost get over each other, but while leaving the small cavities between them. In voxels this would simply merge the muscles, and these base structure would be hard to maintain. So there is when Subdivision sculptin comes very handy as well, cause it's good at generating and maintaining "structure". You can inflate them in surface mode of course... that's why I'm proposing a better base mesh when doing the switch. On the other hand, sometimes "reaching" certain sculpt can be easier when you can go up and down levels, cause these levels rule different aspects of your character, for example:  

Level 1:  Structure

Level 2: Base for smaller detail structure (musles, armor, for example)

level 3: macro details (expressions, tension)

Level 4: detailed defenition of all the character parts

level 5: Micro detail (veins, wrinkles). 

 

That's just an idea, the thing is that you can go up and down and smoothing certain levels details, and smoothing always maintains a very good feeling and is very useful through all the process, cause it never kills the underlying structure. I'm not saying it's the only option, I'm saying that this method should be an option, specially since performance in 3d-coat is so good already.

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I do not see the great loss of detail you are talking about. Here is a picture of after and before running the smooth all tool in surface mode with the settings shown in the second picture... 1,500,000 polygon model.  There is a tiny amount of smoothing as the mesh gets the tangent relaxing but it is not much when I run the settings shown in the picture I uploaded.

 

Note: I was working on this model in surface mode but converted it to voxels with a higher voxel count, then brought the model back to surface mode for the test.

 

Keep sharp edges that appear as result of boolean operations. Test with it and without, whatever works best for your model at that time.

Left side of picture is after using the smooth all tool in surface mode

Right side, before using the tool...

 

Again, this is just to help your current situation and suggestions with information as your post has always help Andrew to look at stuff with more than a passing glance... Who knows, maybe we will get quad subdivisions one day.  :D

post-518-0-46667300-1374371114_thumb.jpg

post-518-0-52400100-1374371134_thumb.png

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I understand subd levels and topology locking. But in 3DC too much is tied to topology change. So instead of subd levels we offer proxy mode where you may manipulate over lower-res mesh with locked topology..

On first stage it was voxel resampling, then it was decimation, on next stage - probably nice and uniform triangulation or quadrangulation.

And yes - as digman tells, tangent smooth helps a lot.

Regarding smoothing - newest Smoother tool is topology/valence independent (this principle was never used before, instead of iterative smoothing it solves equations directly), it may smooth just all very accurately.

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I understand. 3d-coat's aproach is simply not subdivsion level friendly. I find it awesome as it is, however I still say that sometimes it is really relaxing knowing that you can go up and down subdivisions, cause as I said, diferent levels contain different aspects of your model, and somehow my mind is adjusted to organize these "detail levels" in "subdivision levels". I'm sure this happens to many digital sculptors, so if loop subdivision in surface mode is already implemented, I think many people would appreciate the possibility to go up and down. Proxy mode is different, it is not a progressive, "macro to micro" way of working, it's more like a posibility to edit faster. Not the same thing. 

 

Edit:

I must say that about the "base mesh quality" I no longer have complaints, cntrl+shift smoothing and "smooth all + tangent" options are good enough for this :D  . I still thing it would be nice to do a "projected quads" thing directly in the viewport with no need to export/import

Edited by DavidF

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a solution will be this mantis feature request:

 

0000950: Add Sculpt layers to Surface Mode

http://3d-coat.com/mantis/view.php?id=950

 

When sculpting on a layer, the software calculates the difference between the position of vertices after a tool stroke and their original position on the base mesh.
Only the difference in position (the delta) is stored on the layer.

This delta is added to the base mesh and to the deltas stored in all the other layers to arrive at the final shape of the model.

Because the sculpt layers combine in an additive manner, the order of layers is not important to the final result.

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I understand. 3d-coat's aproach is simply not subdivsion level friendly. I find it awesome as it is, however I still say that sometimes it is really relaxing knowing that you can go up and down subdivisions, cause as I said, diferent levels contain different aspects of your model, and somehow my mind is adjusted to organize these "detail levels" in "subdivision levels". I'm sure this happens to many digital sculptors, so if loop subdivision in surface mode is already implemented, I think many people would appreciate the possibility to go up and down. Proxy mode is different, it is not a progressive, "macro to micro" way of working, it's more like a posibility to edit faster. Not the same thing. 

 

Edit:

I must say that about the "base mesh quality" I no longer have complaints, cntrl+shift smoothing and "smooth all + tangent" options are good enough for this :D  . I still thing it would be nice to do a "projected quads" thing directly in the viewport with no need to export/import

Stepping down in resolution is almost exclusively to work in a manner that isn't feasible with the higher resolution version. So, yes....at the end of the day, it's to allow you to work faster when you need to make large scale edits on dense objects. Multi-res proxy work is merely a different approach for the same task.

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Proxy mode will let work faster IF the process is... fast.

 

Atm i found the downgrade/upgrade process very slow if you work with 3M model or more, making it useless -for me-

And only work with surfave mode, any voxel mode is converted to surface after proxy

 

And what about this request to make it accessible easily too ?

0000911: Moving Proxy Visualization to the bottom of the Vox Tree

http://3d-coat.com/mantis/view.php?id=911

 

post-10142-0-36717700-1374654864_thumb.p

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The problem with the proxy visualization is that since I made that image more options have been added, there are 8 of them now. Having that many on the VoxTree might be too much.

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old topic i guess.

 

But it would definitly be sweet if we could implement ( since all the tools are there anyway) multi level sculpting. Basically i think it would be sweet as an upgrade to the Tweak room. Throw some surface tools in there. And a scroll bar for sub-d levels And it would be stupendous =)

 

This way 3d coat would cater to all the people missing the sub-d level workflow. It might not be as good as the 3d coat workflow. But it's really logical And i like have a low poly cage i can always come back to. It makes me feel more in control. I feel that sometimes 3d coat gives me a bit too much freedom. Especially at later stages of the sculpt.

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Multi level sculpting should definitely implemented one way or another. I get the 3D Coat workflow, but have to say that IMO the ZBrush workflow makes more sense and - above all - produces clean surface results far easier.

 

It sometimes is very hard in 3D Coat - or at least much harder than it is in ZBrush - to produce clean, even surfaces without bumps all over the place that cannot be smoothed away (or it takes too much time to do so).

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I was considering this problem recently and I wonder if the reason is as simple as the fact that on a quad based mesh, the normals for each polygon are aligned nicely whereas on a triangle based mesh the polys seem to bend in so many different places especially after a few strokes rather than only being able to bend along edges that are evenly arranged, leading to normals that face all different directions.

 

I've said it before, but I would love to see a 3rd option for quad based meshes in the sculpt room in addition to surface mode and voxel mode.  It would utilize the autotopo algorithm to convert to a quad based mesh for subdivision based sculpting and an appropriate toolset (this would make the tweak room unnecessary).

 

This would be a real game changer IMHO. 

 

Please look into this Andrew!

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The Multi-Resolution workflow in the Voxel Room is a different approach to the same task. You can step down in subdivision at any time, at any level...reduce or decimate. Then have your original version restored, with all the changes translated to it. What's missing is Sculpt layers per object. Andrew said that was going to be a big priority.

 

At some point I do wish he would spend some time in the Tweak room and update it. It's the oldest, most neglected part of the app. Transform gizmo/tools are totally different and not consistent at all. The performance isn't up to par and a bunch of Surface mode brushes should be added there.

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Hi Abn, I think that way is perfectly valid for projects that begin in 3d coat. But what happens when you begin your basemesh in another app and you need to go back and forth while doing a little sculpting in 3d coat? Voxelizing or converting your mesh to Surface mode becomes a destructive step which would require you to do several more steps just to get a quad mesh back into your original app.

A professional tool has to play nice with the other tools in a professional workflow. Otherwise as cool as the features are. The app will be avoided and something that does does bridge the gap well will be used instead.

Not to mention the other benefits of a traditional multi resolution workflow and sculpting on a quad based mesh.

Updates to the tweak room would likely do the trick, however adding quad based multires sculpting to the sculpt room would provide the most power and flexibility for the artist.

Btw, I'm not that familiar with them, but sculpt layers sound really cool.

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If you bring a mesh in from another app, it's always best to send a copy of that to the Retopo Room first, so in the event you need to make large scale edits in the Voxel Room, you can enable "Conform Retopo Mesh" and it will follow the edits you make in the Voxel Room. That was a feature I talked to Andrew directly, about....so one would not have such a broken workflow. Small scale changes via sculpting brushes and such, can be easily massaged (to snap in the Retopo room with the Brush tool, without any real fuss. This is also great if you are told by your client or art director to make some significant changes after the fact.

 

 

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Once you have gone through all the stages to get your finished result into the Paint Room, you can still go back and sculpt some more in the Voxel Room > bake a new Normal/Displacement map in the Retopo Room via the RETOPO menu > Texture Baking tool (not merging to the paint room). Once baked, in the Paint Room you can import those maps via the TEXTURES menu > IMPORT > Normal or Displacement map

 

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I do wish Andrew would streamline the process of sending a mesh from the Paint Room to the Voxel Room and Retopo room....for this purpose (using the Sculpt tools there) and baking maps directly to a new Paint layer...or replacing the mesh in the Paint Room (should you want to fix some geometry issues or even add to the mesh for such things as creating a mouth cavity or something). Currently, people have to send too much stuff outside of 3D Coat and then import it back in. That's just a product of the developer not having to use the app much. Andrew doesn't see the need for this kind of thing.

 

After mentioning this to him multiple times, he said he agreed, but it's one of those things that is going to get pushed to the back of the line on his "To Do" list. I hope the new programmers he recently hired, are able to help accelerate things before too long. A lot of big things to do

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