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Losing UV's on Import when repair a 3D scanned model


CMPharis
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I'm trying to repair a 3D scanned model of a person.

 

I choose 'Repair Scanned Mesh,' then 'Import as Voxels' with 'Close All Holes' selected. On import there are no UV's. If I bring this mesh in to Mudbox or Maya there are UV's.

 

Secondly...

The next step I want to take is to retopologize it automatically in to quads but keeping textures, which means I'd need to use PTEX. I don't want to bake one mesh on to another as it takes too long. In Mudbox that's a couple buttons, can that be done in 3DCoat?

 

Thank you.

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You're importing it as a voxel object, voxels do not have UV's.

 

As for actually solving your issue, I'm not entirely sure. I guess the question here is: "Can I import an already UV'd/Textured mesh, and alter its geometry/retopo it, while keeping the existing texture (either via the same UV's or newly generated ones)"

 

I know you can use PTEX on sculpts, and presumably retopo and bake that data. But the exact pipeline you're after has me a bit stumped, I'd be curious to know the answer myself.

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Gary is right, however, if you click the V icon, (on the left side of the layer) of the VoxTree layer which the object will be applied to, it will switch to "S," meaning the object will come in as a Surface mode object...rather than Voxels. Another alternative to this step is, when the IMPORT tool is active, in the Tool Options panel, make sure "Import w/o Voxelization" is checked. It will automatically switch the layer to Surface mode in the process.

 

The reason it's important to be in Surface mode is that 3D Coat will try to bake the color from your color image map onto the vertices of the Surface mode object. But remember, the higher the poly count, the more resolution the model has to accurately capture that image data. If it all comes in looking right, you can proceed to Auto Retopologize the model, but you will have a choice to make regarding the UV's. You can bake using Ptex, or you can choose AutoUV in the Baking Export dialog.

 

If you could PM me, and provide a copy of the scanned mesh strictly for demonstration/training purposes only, I could record a tutorial on how to do this process, using your model, so others with a similar task will know how to handle it, as well...if that is ok by you?

 

Here is a video showing image maps being baked to the vertices of the incoming mesh.

 

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Okay thanks I'll look in to these suggestions.

 

I've tried importing as a surface too, not voxels, and the UV's still aren't there.

 

Mudbox nearly does everything I want, except it won't close holes or auto-cleanup. Baking from one map to another is not an option for me. I need to do 300 of these a week so it needs to be incredibly fast.

 

All I need to do is scan the mesh, import the OBJ, clean up artefacts and texture then do a quick retropologize with PTEX so it has cleaner geometry to add a little more definition before printing.

Everything here is a few buttons in Mudbox, it just doesn't clean up the geometry automatically like 3DCoat does.

 

No other software I've tried does a clean up like 3DCoat.

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So I don't think 3D Coat is the tool for me. I need to automatically repair a 3D scanned mesh, to the efficiency of 3D Coat without it voxelizing it. Because of course I need to keep the materials, why would I not want them?

 

I'll have to try some other software.

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I don't think you have understood the post from AbnRanger.  Of course you can keep your materials. 

 

 

All I need to do is scan the mesh, import the OBJ, clean up artefacts and texture then do a quick retropologize with PTEX so it has cleaner geometry to add a little more definition before printing.

 

No other software I've tried does a clean up like 3DCoat.

All this is doable in 3D-Coat.

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I don't think you have understood the post from AbnRanger.  Of course you can keep your materials. 

 

All this is doable in 3D-Coat.

 

Voxelizing the mesh seems to be the only way to automatically clean up a 3D scan, but it removes my UV's. How do I do it?

The only option that seems to bring in my UV's is the "Paint UV Mapped Mesh (Per-Pixel) one.

 

You also suggested right clicking the volume and selecting "autopo" but the tutorials I've seen show people clicking the volume, but there's nothing in my layers that's the actual mesh to right click.

http://prntscr.com/akdkyy

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So I don't think 3D Coat is the tool for me. I need to automatically repair a 3D scanned mesh, to the efficiency of 3D Coat without it voxelizing it. Because of course I need to keep the materials, why would I not want them?

 

I'll have to try some other software.

If you are going to take a scan into Mudbox with a dense scan mesh, can you please explain just how you can get Mudbox to Auto-Retopologize it AND transfer the original UV's to the Auto-Retopologized mesh....in just a few clicks? Did you miss the part where I said you could either do an AUTO-UV on your Auto-Retopologized mesh, or use PTEX? 3D Coat can then bake all that color info onto the new UV map or PTex...which is an elegant Auto UV tool Disney developed (downside is that the map has the polys arranged in a non-visually coherent manner).

 

In both Mudbox or 3D Coat, you will still have two completely different meshes, and in neither case could you transfer your UV's. It just doesn't work that way, when you use an auto-retopologize toolset. Mudbox would have to bake the image date from the original scan mesh to the new mesh. 3D Coat does the same thing, as I mentioned in my previous post. Where is 3D Coat lacking, then?

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Voxelizing the mesh seems to be the only way to automatically clean up a 3D scan, but it removes my UV's. How do I do it?

The only option that seems to bring in my UV's is the "Paint UV Mapped Mesh (Per-Pixel) one.

 

You also suggested right clicking the volume and selecting "autopo" but the tutorials I've seen show people clicking the volume, but there's nothing in my layers that's the actual mesh to right click.

http://prntscr.com/akdkyy

If you committed the imported mesh to a layer, there should be something in the Vox Tree panel. Could you close the app and restart and see if it was just some UI glitch?

 

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I sent you the mesh, I'm sure I'm just being stupid. I have a good background in 3D but a lot of this voxel stuff I've never seen before in Autodesk software. I only ever do hard surface modelling in Maya.

 

Perhaps I worded it wrong. I don't want to transfer my UV's, just the materials. PTEX does the job in Mudbox. There's a "retopologize with PTEX" option which I'm trying to figure out in 3D-Coat. Just my version of the software seems to be slightly different to those people use in the tutorials, I've tried following them step by step.

 

But other than that problem I also need to figure out how to have 3D-Coat clean up my scanned mesh automatically without destroying my UV's. I've tried your method, there are like 14 different import options, I never know which one to choose. The tutorials show someone dragging a mesh in to the viewport and the import tool settings pop up but dragging in doesn't work in my version. I'm using 4.5.19 (educational).

 

If you are going to take a scan into Mudbox with a dense scan mesh, can you please explain just how you can get Mudbox to Auto-Retopologize it AND transfer the original UV's to the Auto-Retopologized mesh....in just a few clicks? Did you miss the part where I said you could either do an AUTO-UV on your Auto-Retopologized mesh, or use PTEX? 3D Coat can then bake all that color info onto the new UV map or PTex...which is an elegant Auto UV tool Disney developed (downside is that the map has the polys arranged in a non-visually coherent manner).

 

In both Mudbox or 3D Coat, you will still have two completely different meshes, and in neither case could you transfer your UV's. It just doesn't work that way, when you use an auto-retopologize toolset. Mudbox would have to bake the image date from the original scan mesh to the new mesh. 3D Coat does the same thing, as I mentioned in my previous post. Where is 3D Coat lacking, then?

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What option should I use to import my mesh with? Like I said the only one that seems to keep my UV's is the "Paint UV Mapped Mesh" option. But then that won't let me right click it as a layer, it also won't give me the Import Tool options.

 

If I try to import my mesh in to the sculpt tab with the Import tool, which gives me the Import tool options and select 'Import w/o Voxelation' I still don't get my UV's.

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This is all I'm doing. My mesh definitely has UV's.

1. http://prntscr.com/ake4ij
2. http://prntscr.com/ake4pg (UV's are completely blank)

 

Importing should not be such a difficult process. It should just be, "File > Import > Select Mesh" and there you go, done, it's in, it has UV's, everything. If I try to import FBX's it's just invisible. I don't know wth I'm doing so wrong.

 

I understand the voxel thing now and I get that that can't have UV's. But not how to import my mesh with UV's, voxelize it so it cleans up the scan, then convert it back to a surface so that I still have my UV's.

Edited by CMPharis
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What option should I use to import my mesh with? Like I said the only one that seems to keep my UV's is the "Paint UV Mapped Mesh" option. But then that won't let me right click it as a layer, it also won't give me the Import Tool options.

 

If I try to import my mesh in to the sculpt tab with the Import tool, which gives me the Import tool options and select 'Import w/o Voxelation' I still don't get my UV's.

You won't get any texutres without the .MTL file. No program can assign an image map exported with an OBJ file, without that accompanying file

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Ah... one thing to note, the UV room is a weird one. I think it only applies to when you bake an object within 3dc (same with Tweak I believe)

 

You're going to lose your UV's either way. Even if you import as a surface object you will not retain UV's. The only way to keep UV's on an imported mesh is to import it straight into the paint room (as per-pixel or PTEX).

 

The thing AbnRanger is showing is that you should be able to embed your colour information from an image file, onto the verts of the surface object you wish to import. So more verts = more texture detail. From there, you would do an autoretopo, and then you'll have to bake (you can also set the UV's to generate automatically)

 

The problem, if I'm understanding correctly... is that you absolutely need to jump into voxel mode at some point as that's the only way to repair/clean the mesh. This is the heart of the problem, since voxel mode = bye bye vert colour, as well as UV's.

Edited by Gary Dave
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This is all I'm doing. My mesh definitely has UV's.

1. http://prntscr.com/ake4ij

2. http://prntscr.com/ake4pg (UV's are completely blank)

 

Importing should not be such a difficult process. It should just be, "File > Import > Select Mesh" and there you go, done, it's in, it has UV's, everything. If I try to import FBX's it's just invisible. I don't know wth I'm doing so wrong.

 

I understand the voxel thing now and I get that that can't have UV's. But not how to import my mesh with UV's, voxelize it so it cleans up the scan, then convert it back to a surface so that I still have my UV's.

It's not a difficult process. You just have to have the patience to learn how the applications (you are trying to use) works. If you just try to dive in with a scant amount of information, you are going to be frustrated, naturally. It's that way with all of us when learning a new app

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Ah... one thing to note, the UV room is a weird one. I think it only applies to when you bake an object within 3dc (same with Tweak I believe)

 

You're going to lose your UV's either way. Even if you import as a surface object you will not retain UV's. The only way to keep UV's on an imported mesh is to import it straight into the paint room (as per-pixel or PTEX).

 

The thing AbnRanger is showing is that you should be able to embed your colour information from an image file, onto the verts of the surface object you wish to import. So more verts = more texture detail. From there, you would do an autoretopo, and then you'll have to bake (you can also set the UV's to generate automatically)

 

The problem, if I'm understanding correctly... is that you absolutely need to jump into voxel mode at some point as that's the only way to repair/clean the mesh. This is the heart of the problem, since voxel mode = bye bye vert colour, as well as UV's.

True, except IF you have vertex color applied to a Surface mode mesh > convert to Voxels, 3D Coat will still try to store the color information and bake it back onto the model once you switch back to Surface mode. Depends on just how much work is done in voxel mode, but 3D Coat does try to keep as much of the image data as it can.

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Carlosan
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Gary Dave was awarded the badge 'Helpful' and 1 points.

IF you have vertex color applied to a Surface mode mesh > convert to Voxels, 3D Coat will still try to store the color information and bake it back onto the model once you switch back to Surface mode.

 

 

Ah okay, that's a good bit of information. So... I think this is what CMPharis needs to do:

- Import his .obj as surface object (with .mtl file and texture image in same location as the obj? So 3dc knows what colour to apply to the verts?)

- Switch object to voxel mode to repair it (little fuzzy on this, does it require manual work here, or does switching to voxels repair the mesh enough automatically?)

- switch back to surface

- perform auto-retopo

- bake to PTEX? Or per pixel with auto UV's

- Export out new retopo + textures.

Yes? No?

Edited by Gary Dave
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Ah okay, that's a good bit of information. So... I think this is what CMPharis needs to do:

- Import his .obj as surface object (with .mtl file and texture image in same location as the obj? So 3dc knows what colour to apply to the verts?)

- Switch object to voxel mode to repair it (little fuzzy on this, does it require manual work here, or does switching to voxels repair the mesh enough automatically?)

- switch back to surface

- perform auto-retopo

- bake to PTEX? Or per pixel with auto UV's

- Export out new retopo + textures.

Yes? No?

That's correct. But, as mentioned in the video above, it's best to subdivide the model quite a bit before importing it into the Sculpt workspace. So, If I were coming from 3ds Max, I would subdivide it a few times in Max > import it into Sculpt room.

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I'll try this. I've never use OBJ's before so I've never understood what MTL's are. I always use FBX. I thought bringing an OBJ in to Maya or Mudbox it never seems to need the MTL, but I guess I just never noticed.

Whenever you export an OBJ, if you have a UV assigned to the model, it should generate an MTL file that accompanies it. This isn't a 3D Coat thing. It's an OBJ thing

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Ah okay, that's a good bit of information. So... I think this is what CMPharis needs to do:

- Import his .obj as surface object (with .mtl file and texture image in same location as the obj? So 3dc knows what colour to apply to the verts?)

- Switch object to voxel mode to repair it (little fuzzy on this, does it require manual work here, or does switching to voxels repair the mesh enough automatically?)

- switch back to surface

- perform auto-retopo

- bake to PTEX? Or per pixel with auto UV's

- Export out new retopo + textures.

Yes? No?

 

I tried that, still no UV's. I can bring the mesh without the MTL file using the "Paint UV Mapped Mesh" and I see my UV's just fine. I can bring it in to Maya too without the MTL and I see the UV's and can apply my texture. I suppose I'll just have to wait for Abn's video or guide to explain it because this is really baffling me. ^^;

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when you export an OBJ with a UV map assigned to it, it should generate an .mtl file, like you see here...

 

I understand that, but I've actually put the OBJ in to a folder, deleted the MLT, brought the OBJ in to Maya and it has UV's.

Why are we even using OBJ's, aren't FBX's the new modern norm?

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The .mtl isn't for the UV's, as I said before, you're going to lose your UV's either way when importing to the sculpt room (either as voxels or as surface)

No UV's. Nada UV's. UV's finito, gone, banished, disregardo.

 

The .mtl is so 3dc knows to assign vert colours to that of your texture. It will basically drop your UV's and replace them instead for vertex painted information on your surface model. (more verts = more texture)

 

As for FBX, yes it's a standard, and I know there are options to embed media on export, this might be the same thing as the .mtl for obj's, you'll have to try it. But again, the .mtl isn't for UV's, it's a material file, that will tell another application (not just 3dc) what material need to be assigned to the mesh.

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I understand that, but I've actually put the OBJ in to a folder, deleted the MLT, brought the OBJ in to Maya and it has UV's.

Why are we even using OBJ's, aren't FBX's the new modern norm?

You could try an fbx. It should import as well. I'm just not sure it will have the color image baked into the vertices of the model. I'll have to check, if you have an FBX version with the image map assigned, when you export. What I am thinking the problem is, that you may have a third party render shader applied to the object when you export, and it isn't writing the color map assignment upon export. 3ds Max does this if you try to use anything but a default Max shader

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