Jump to content
3DCoat Forums

Detailing Problem - Need Advice


Chip_M
 Share

Recommended Posts

  • Member

I'm running into some issues and need some workflow advice because I'm probably missing some things on how to best manage the task at hand for efficiency. I've sculpted the basic form for a character's hair and now I'm adding the fine details that I'll bake into a normal map so that there will be individual strands in the specular highlights. I'm using the scratches2 tool in spline mode with a radius of about .250 to create the strands. I lay down my spline and apply scratches2 and then switch to freeze and apply it along the same spline so I mask what I've already done and can get the look of interweaving strands without ending up with crosshatching. In order to resolve the strands and not have them pixelated junk I had to crank the resulution up to 16x. This is causing me all sorts of problems. I've lost hours of progress to out of memory crashes, have holes and tears appear in the surface for no reason, and it's just generally turning out to be a miserable experience. I tried caching the mesh in surface mode and that seemed to be working great, until I tried to save my progress and had another out of memory crash and a corrupted save file as a result. This is on a machine with 32GB of RAM. How are people able to do very fine detail in 3DC in surface mode without these problems? This is in the latest beta build. Any advice would be greatly appreciated.

Link to comment
Share on other sites

  • Member

In surface mode isn't the size arbitrary? Seems the only thing that would matter is polygon density, and it had to be dense enough to resolve the scratches. Muscles and curves are great for building the corn but not for final detailing. I tried to take as screenshot when the first hole appeared which is usually a sign of impending doom but it was too unresponsive at that point. I'll take some tomorrow to show what I'm doing.

Link to comment
Share on other sites

  • Reputable Contributor

In surface mode isn't the size arbitrary? Seems the only thing that would matter is polygon density, and it had to be dense enough to resolve the scratches. Muscles and curves are great for building the corn but not for final detailing. I tried to take as screenshot when the first hole appeared which is usually a sign of impending doom but it was too unresponsive at that point. I'll take some tomorrow to show what I'm doing.

In many cases, that is true, but you can build hair strands on top of head, while being on it's own separate layer. I just find that working with Muscles tool in Volume more, is more fluid and fast. It's much slower, IMHO, in Surface mode, for some reason. I think it's because 3D Coat is literally just building the strands with voxels, and is less calculation intensive than build geometry from scratch. It's also why merging different layers and booleans are MUCH faster in Volume mode, than surface mode. Surface is faster in just pure sculpting terms. But most everything else, Voxels are faster.

Link to comment
Share on other sites

  • Member

Here's a screenshot from 3ds Max of the end result of one I'd done this way previously without running in to this problem. I'm not really sure what's different this time around other than that I'm doing the strands a bit smaller than I did on this one.

 

R2ROjDy.jpg

 

Here's the finished product inside Second Life which is the target platform.

 

PECvl7F.jpg

Edited by Chip_M
Link to comment
Share on other sites

  • Member

In polygon density you mean? If it's less dense it won't resolve the scratches tool cleanly. Since the end result of the scratches ends up being a specular map I could do it outside of 3DC but being able to work directly on the form rather than on the UV template makes it much easier. I've exported the finished base as a new obj and am going to experiment with changing it's scale before brining it back into 3DC for another try. I'm really at a loss as to why I was able to do this without issue before and this time can't get more than a few strokes in before a crash. If memory serves I was at 8X last time, but was hoping to achieve a finer, cleaner result this time. Can 3DC just not handle that kind of poly density?

Link to comment
Share on other sites

  • Member

The first hole appears. This is in the middle of a spline stroke and it should only be moving vertices. Notice how the freeze is darker around it as if it applied the stroke twice at that control point? Am I hitting a bug in the spline tool?

 

u1xsQWG.jpg

 

 

When I brought the exported obj into Max to check scale it was huge so I scaled it down to a realistic size in real world units, reset its xform, and reexported to 3DC to see if that would make a difference. It had been 67 million polys at 16X previously, and is 44 million at 16X now. I can understand scale making a big difference in voxel mode, but what difference does it make in surface mode beyond floating point precision?

Link to comment
Share on other sites

  • Reputable Contributor

Every once in a while I get this kind of issue, but it's pretty rare. I don't switch to voxel mode, unless I need to do some kind of Boolean operation or if I need to use the Muscles tool, etc. Didn't have any trouble at all working with hair on this model....lots of LiveClay work on the skin pores and hair...used the Crease clay (inverted) tool on the eyebrows, etc. Try and send the file to Andrew (support@3d-coat.com) and explain the trouble you are having. He's usually pretty responsive regarding bugs.

 

In all of this, you never did mention what build you were using. Sometimes people are using a very old beta build and they are madder than a hornet cause the BETA build isn't rock solid. Andrew did a lot of work recently to fix holes in meshes and such.

 

  • Like 1
Link to comment
Share on other sites

  • Member

I was using the latest beta build. I reverted back to the current release build to see if that made a difference but I encountered the same problems there as well. Random holes appearing in the mesh and out of memory errors. The bottom line seems to be that I just can't work in sufficient resolution to do what I want to do. I'm currently working on retopo and will try getting the effect in the paint room instead.

 

One thing I can't seem to figure out is how to get a brush with a mask to behave the same way the scratches tool does. I thought maybe I could use a brush alpha that's just a few dots and have it follow along a spline path and achieve basically the same thing, allowing me to do several strands at once. Is something like that possible? If not I'm not going to be able to do it in the paint room either. Having to do one strand at a time would take days. Because of the length of the strands and needing the look of finely combed hair, being able to use the stroke along spline is really what I need. It's not something I can freehand and get the look I'm after.

Link to comment
Share on other sites

  • Reputable Contributor

You can do what you are trying to do, in the Voxel Room, but it's hard to tell what really is going on, without a screen recording of some kind. JING is always a good free option...and you can upload the rendered video to their server (screencast.com)

 

 

The stills help a little, but a recording helps best on really tricky issues. Try to close the file > close the app > delete the Options.xml file in your "MyDocs/3D Coat V4 folder (it gets buggered up once in a while and exhibits bug-like behavior). Then re-open the app and file.

 

This might help a bit as well:

 

There is also a new FILL HOLES tool in Surface mode. You might want to test that.

Edited by AbnRanger
Link to comment
Share on other sites

  • Member

I should have also mentioned that I'm running the 64bit CUDA version, Win 8.1, 32GB RAM, and a GTX 780. It's possible I could be running into a RAM or drive issue but I've not had issues previously. When I first started having holes appear I tried the fill holes tool and 3DC didn't find them even though they're clearly visible in wireframe.

 

There may just be something funky with this model too. I built the base forms in Max using splines with cross section and surface modifiers then shelling them and adding a turbosmooth. I merged those pieces into a voxel layer in 3DC, closed invisibe hulls and filled voids, then finished off the base form with a lot of smoothing, and laying down curves and blending them in, I didn't have any problems at all until switching to surface mode to do strand detailing.

Link to comment
Share on other sites

  • Reputable Contributor

I should have also mentioned that I'm running the 64bit CUDA version, Win 8.1, 32GB RAM, and a GTX 780. It's possible I could be running into a RAM or drive issue but I've not had issues previously. When I first started having holes appear I tried the fill holes tool and 3DC didn't find them even though they're clearly visible in wireframe.

 

There may just be something funky with this model too. I built the base forms in Max using splines with cross section and surface modifiers then shelling them and adding a turbosmooth. I merged those pieces into a voxel layer in 3DC, closed invisibe hulls and filled voids, then finished off the base form with a lot of smoothing, and laying down curves and blending them in, I didn't have any problems at all until switching to surface mode to do strand detailing.

I think I recall some mention of holes/explosions when using the scratch brushes...but I thought that was some time ago. I never use them. Personally, I'd just rely on the Gum brush for that, and a good brush alpha with those scratches/lines. In the Brush Options panel, you can experiment with SPACING at the bottom and check rotate brush with curve, etc. Another thing you could do is create a group of strands (use a plane that is stored on another separate layer) with the Muscles tool, or snakes tool. Once you have the strands looking right > drag and drop that (strands only) layer into the models pallet. This will store it in MyDocs/3D Coat V4/ VoxStamps/Objects.

 

Now go to the STRIPS pallet and click on the + icon. This will let you find that new obj file of the strands (you just created), once you find/pick it, you'll have a new panel come up that lets you create a 3D brush alpha from a model. Instead of just an object in the center, you want this to extend from the top to the bottom (no gaps)...so that the strips can continue on in an uninterrupted pattern, along the length of your stroke/spline.

 

You can see the process about halfway through this video:

 

 

This is what was used for the sticthes in this video:

 

Edited by AbnRanger
Link to comment
Share on other sites

  • Member

I finished doing retopo and UV layout and tried making a custom strip and using it to paint depth in the paint room instead. It's working perfectly so far and giving me the same ability to switch between applying the brush along a spline and then freezing the same stroke. Thanks a bunch for the help.

Edited by Chip_M
Link to comment
Share on other sites

  • Reputable Contributor

I finished doing retopo and UV layout and tried making a custom strip and using it to paint depth in the paint room instead. It's working perfectly so far and giving me the same ability to switch between applying the brush along a spline and then freezing the same stroke. Thanks a bunch for the help.

Yeah....some things can be done as easily or more efficiently in the Paint Room. Skin Pores and very fine wrinkles is one such example. Some Dragon Scales and the like, would be another.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...