Cloth retopo.

[Gary Dave]

Having a very frustrating time with 3d coat today!

 

First off, I created a retopo of a shirt, used the cloth tool in voxel room on that mesh, created it as a voxel object when I was finished, then sent it back to the retopo room, only for my original retopo to go absolutely crazy when trying to snap to the voxelized shirt.

 

Annoying, but whatever, I decided to just ditch the retopo mesh, keep the voxelized version and manually make a new retopo over it. And now I keep getting verts snapping to the inside of the cloth instead of the outer surface which is just driving me absolutely insane.

 

I then spent a good 10 minutes trying to find the freeze tool in the voxel room, in the hopes of painting an area for the retopo room to ignore, but apparently no such thing exists?

 

I know that retopo > cloth > retopo is a common workflow (even built into the cloth tool), so I'm really hoping that I'm missing something stupid here, because I can't keep working like this.

 

I don't mind starting from scratch on the shirt, so long as I know the pipeline will definitely work, at the moment it feels like every new corner I turn with 3d coat, I'm met with something unexpected.

 

[stusutcliffe]

I cant really offer a solution to this because it all too clever for me! But having done a few experiments with this I know where you are coming from. I usually use a combination of Carrara and 3dcoat for my limited attempts at cloth sims.

I have never tried to "snap" back a retopo to the simulation, But I am aware of 3dcoat getting confused by thin sections. Perhaps some lateral thinking? Maybe make the cloth really thick by increasing the inset depth,thus giving the snapping back something easier to go at ? When I need my finished cloth to have a thickness, it is usually at the sleeve, I extrude it in Carrara later.

 

( I dont think the freeze tool works on Voxels anyway, because it a solid lump of "stuff" so it would not know what to freeze. You could change to surface to freeze,but like you say I dont think there is a way of using this to not retopo an area.)

 

 

For what its worth my current workflow is something like this,  https://dl.dropboxusercontent.com/u/7219382/drape.pdf   It a really quick thing I did to show someone on the Carrara forum. But obviously not much use to you if you do not use Carrara, but I suppose any 3d software will be capable.

 

If you find any sneaky workarounds let the forum know.

[Gary Dave]

Hey stusutcliffe, thanks for the reply.

 

Yeah I had thought about increasing the thickness after I made the post, I'm avoiding 3d coat at the moment though to allow myself to "cool down", hah.

 

I'm honestly more tempted to just ditch cloth all together and sculpt the clothes the "old fashioned" way, this will certainly be easier to deal with at the retopo stage.

[stusutcliffe]

Yeah, if its a tight fitting shirt or jacket its good to sculpt ( with a bit of google reference) But its good to do a dynamic if you have a flimsy fly away bit! ( or a poncho.......strange thing is , I have never needed to make a poncho...)

 

I usually have a cool down period when I do Autopo....not quite figured that one out yet. The latest incarnation does seem to work better for me but it just takes  flippin' ages to calculate! Unfortunately my 5+ year old computer is going to have to be a 6+ year old computer.

[Ghastly]

I've got a bunch of meshes I made while I was using the beta of Marvelous Designer 3. I wonder how well they'll retopo in 3D Coat. MD3 for all it's faults actually does a pretty decent cloth sim although the mesh it generates is made of random tris. Theoretically I believe I could use 3D Coat to mix and match the meshes I've already made in MD3's beta to create an infinite combo of outfits (ie. sleeves from this outfit with torso from this outfit with skirt from this dress and collar from this shirt).

[ajz3d]

It's the weakest side of 3D Coat retopo and I'm glad you started this thread. Maybe we can hope for some improvements in this department.

Retopo mesh vertices snapping to backfaces is nothing new and I constantly have to fight them when doing clothes and other thin stuff. If I'm to create a cloth, I try to keep it a non-solid (thin-walled or whatever other term we can come up with) as long as possible. When I feel that my work with a particular cloth is complete, I move to retopo room to retopologise it. This eliminates the problem of dealing with "sunken" vertices. At least in most cases, because if the cloth has some pockets or other accessories that are not merged with the main cloth surface (they're children of the cloth layer or they are merged with it, but are separate meshes), it will not work and I have to carefully inspect the surface of my retopo mesh and fix any errors I manage to catch.

Anyway, after I'm done in the retopo room, I switch back to voxel room and add thickness with a Turn surface to shell command. This however introduces new problems, because 3D Coat generates thickness with no spans at all, which means that it will react to brushes more severely than other parts of your layer. A remedy to this is a conversion to super hi poly voxel mesh. Depending on your system specifications, you can get away with it or not. I can't, even though I work on quite a beefy machine. Most of the time I have to resort to using CutOff tool to fix the bumpiness aused by various smoothing tools (tangent smoothing included) at the edges of the cloth. It's impossible to smooth it even with Smoother tool.

And what about the thin-walled retopo mesh? I export it to external modelling program to add some thickness to it. Just enough so it encompasses the sculpture.

 

P. S. I even tried to temporarily scale the cloth layer up in order to increase the distance between the outer and inner walls of the model. To no avail of course. Still got sunken vertices everywhere.

[Gary Dave]

I've been playing with it more and more, and I can certainly understand the difficulty in coding up something like this... I mean, what if you wanted to snap to the inner surface? How do you really expect 3d coat to know what you have planned. I was thinking about some sort of "Fill inner" tool, that would just, well, fill the inside of a tee shirt, for example, but even if that was a relatively "simple" job to do, there are always going to be cases where you want the best of both worlds, like "Yeah I want a tee shirt, and yeah I need the mesh filled.. but umm, not the sleeves or the bottom!"

 

I managed to get a good work flow with just using the points/faces retopo tool, there was still the odd issue here and there, like literally 2 verts would end up on the inside, but on the whole it was a pretty pleasant experience. It only starts to get messy as hell when using the strokes tool... which is a shame, as I often lay out the major forms with strokes, but oh well.