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Hello, and a few questions

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Hello everyone, i just found this software recently and i've been having a lot of fun with the trial and i'm seriously considering buying it. I have run into a problem though which has stopped me in my tracks and i was wondering if anyone can give me some advice/suggestions.

My problem is with using a mesh to create a new voxel volume. I have tried mutliple different import formats (obj,lwo,3ds) and experimented a lot with scaling and increasing the density of the volume before i create the object, but 3D-Coat always seems to create some very strange artifacts. Generally the profile of the mesh transfers well, but concave surfaces seem to get filled in most of the time, and sometimes the artifacts they create (lots of 'stepped' patterns and holes) will be projected to the opposite surface of the model. Is this a known problem, and has there been any word on fixing it?

I'm very new to modeling so perhaps i'm doing something incorrectly, but this feature is absolutely amazing when it works right and would have me sold right away if it worked reliably!

Another thing i was wondering about is the possibility to paint directly to the voxels in the future. I understand that 99% of people only use the voxel models to bake normal/displacement maps for low poly meshes, but i think it would be a very nice feature! I have read that some game engine developers are thinking about using voxels for next generation engines (for world objects and anything that doesn't need to animate) so perhaps this might actually become very relevant in the next few years. I am guessing that it won't be possible to add this while 3D-Coat renders voxels as polygons for sculpting, but maybe there could be an alternate rendering option to show the 'true' voxel volume?

Anyway, thanks a lot for your time! The software is really amazing, and if i can only fix this problem with merging meshes i will be all set!

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Are you using an open mesh? For example, a head with the neck area not closed. If so try closing it yourself or clicking the Make Mesh Closed button while merging.

As for painting on voxels, it has been discussed many times before and I don't think we will see it happen very soon. aside from how extremely difficult it would be, most people just don't need or want it bad enough.

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Are you using an open mesh? For example, a head with the neck area not closed. If so try closing it yourself or clicking the Make Mesh Closed button while merging.

As for painting on voxels, it has been discussed many times before and I don't think we will see it happen very soon. aside from how extremely difficult it would be, most people just don't need or want it bad enough.

Sorry i should have been clearer in my post. It's not an open mesh, it's a solid object made only by subdividing faces and extruding etc.. It seems to happen mostly on circular or irregularly shaped faces that are drawn in from the surface (hope that makes sense). I also tried the 'close mesh' option on import but that didn't seem to alter anything at all. Like i said i am literally just getting started with modeling (4 days in so far!) so perhaps there is actually something wrong with my mesh to begin with. I was just wondering if this was a known bug, or does the merge function usually work perfectly if everything is ok with the source mesh? If so i will have to read some more Blender tutorials and try and find what i'm doing wrong.

That's a shame about the Voxel painting! My mind literally exploded at the thought of it lol. I would really like an alternate rendering mode to show the true voxel form of the object, but i understand that the current polygon method works very well for organic modeling. Oh well maybe in the future it could be added - it's certainly not a deal breaker.

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I takes a little experimentation sometimes to get a good merge in the Voxel Room. You may want to subdivide your model a time or two (from within the Voxel Room), and then increase the resolution of the voxels before you hit "Apply." You can also go straight into the Retopo room as soon as you get your model merged and import the original mesh there. Along the way, as you sculpt, you can re-snap the mesh to the changes, and when you are done, you can use your original mesh as a base to tweak from, instead of having to start retopo'ing from scratch.

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Hi Cube and Welcome

Once you learn how better to check your mesh as you learn modeling,you will find less and less problems merging for voxels.Holes in the mesh causes the problem you are having. Check your mesh for duplicated or unmerged vertices. Even one unmerged vertice will cause a hole you cannot even see. Most software can check for unmerged vertices or duplicated ones. 3DCoat cannot fill an unmerged vertice hole. You can even upload the obj model here and I will take a look at it if ya like...

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Thanks for the help guys, i'll try subdividing the mesh a few times first. If it doesn't fix it i'll spend a couple of hours going over Blender again and see if i can figure this out, if not i will post the model for you to look at.

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I managed to fix my issue, turns out that a ring of edges were indeed not connected properly, even though they appeared to be physically joined. Just tried several merge operations with the fixed mesh and it's working great, the results at higher voxel density are really quite impressive! I think i'll have to upgrade my computer if i buy 3D-coat though, some of the merges have taken 10 minutes - it reminds me of watching my brother rendering images on his Atari ST when i was a kid :)

Thanks again for your help guys, it's all bit confusing at the moment, but i'll get there eventually - i hope!

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I managed to fix my issue, turns out that a ring of edges were indeed not connected properly, even though they appeared to be physically joined. Just tried several merge operations with the fixed mesh and it's working great, the results at higher voxel density are really quite impressive! I think i'll have to upgrade my computer if i buy 3D-coat though, some of the merges have taken 10 minutes - it reminds me of watching my brother rendering images on his Atari ST when i was a kid :)

Thanks again for your help guys, it's all bit confusing at the moment, but i'll get there eventually - i hope!

Great, you got it working, Try merging your model in at a lower voxel resolution,just enough to catch all the details(less time to merge that way). Sculpt in your larger form changes, then increase the resolution for your finer details.

Blender is great but sometimes, your just want a straight subdivision modeller. Check out Wings3d (Free)

It has a very intuitive interface and is very quick for making basic models for sculpting though it's not limited to basic modeling.

http://www.wings3d.com/

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Cool thanks digman, i'll have to give that a try. I grabbed Blender because it was the only free 3D app i knew of, and the documentation is good, but it is really much too complicated for the basic things i am doing!

About the merge times, yes you are definately right, at lower levels it calculates very quickly, but if i merge an object with ~16m triangles it takes a while. I also tried doing a 24m merge just to see what would happen, i ended up closing 3D-Coat through task manager as it just kept going and going and it was having to use the page file a lot. I have a Core2Duo 2.66ghz with 4gb of ram, so maybe upgrading to 8gb might be worth it. I don't have the money for an i7 system at the moment so i'll have to learn what i can handle complexity-wise.

The first models i have been experimenting with are just very geometric doodles, but i was surprised at how well they can be represented with 8m voxels or so. The only telling areas are radial lines etc.. but with some very light smoothing they look great too. I have yet to scuplt anything organic (just been doing surface detail experiments), but i look forward to trying that.

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Hi Cube and welcome to the community :drinks: !!!

I may suggest you to avoid very thin details because low-res merging to voxels can destroy them. I suppose that you you have 16 or 20 millions of tris because you scale the object you're merging too much. Am I right? You could send one of your base meshes (in OBJ for everyone or in BLEND for me and other blender users) and I'll try to find compromise :)

About Wings3D and Blender. I started with Wings3D. It is really cool 3D app for box modeling. Very intuitive, easy to navigate and use. But has it's limitations. After that I've tried Blender (it takes some time to get used to it!) So now I don't use Wings at all.

The cool thing about Blender it is a complete 3D package... So good luck! ;)

If you'll have 3DC-Blender connection questions you may freely ask (here's a lot of people using Blender)

Hope will see your works soon! :brush:

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Hi Cube and welcome to the community :drinks: !!!

I may suggest you to avoid very thin details because low-res merging to voxels can destroy them. I suppose that you you have 16 or 20 millions of tris because you scale the object you're merging too much. Am I right? You could send one of your base meshes (in OBJ for everyone or in BLEND for me and other blender users) and I'll try to find compromise :)

About Wings3D and Blender. I started with Wings3D. It is really cool 3D app for box modeling. Very intuitive, easy to navigate and use. But has it's limitations. After that I've tried Blender (it takes some time to get used to it!) So now I don't use Wings at all.

The cool thing about Blender it is a complete 3D package... So good luck! ;)

If you'll have 3DC-Blender connection questions you may freely ask (here's a lot of people using Blender)

Hope will see your works soon! :brush:

Yes it's only the thin details that give me the problem with merge - but i will learn eventually how to get the details with sculpting/projection instead i think. Here is a quick render of new model made this morning for fun (made with Google Sketchup for speed), it's a kind of Art-Deco radio type of thing. You can see that at default model scale even when i increase density in VoxTree volume (8x), the details come out poor, but if i scale the model 10-16m it can work very well (some small artifacts on the radial lines, but easy to smooth with very light pressure).

One thing i noticed though when i tried to render this, the yellow box that comes up (custom size) is totally out of line with finished picture, maybe this is a known bug?

post-2502-12672413552468_thumb.jpg

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