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graviel
12-31-2015, 12:24 PM
First of all happy new year.

I am having some estrange behavior.

I have a scene in Layout with many objects loaded (about 20), all of them CC subdivisions and some of them have edge rendering on and a few endomorphs.

As expected, if subdivision order is set to "first" they look broken.
I changed the subdivision order to "last" in every one of them, they look correct but after a while they show broke again,
If a swap from "last" to "first" and back to "last" they start rendering well again but after a while, they do broke again, I yet could not figure out at what stage this happends but somehow the geometry engine seems to loose the north. If I would start fixing the subdivision order one by one, after fixing 5 of them the first one will show broken..

I am using LW2015 update 3 in OSX.

Any hints how to deal with this? The scene is otherwise ready to render...

Thanks!

graviel
12-31-2015, 12:29 PM
If I would change any other options they do look ok once again for a while, for example if I change the subpatch level. But once again after a while they display wrong both in openGL, in the VPR or in the render window.

ernpchan
12-31-2015, 04:23 PM
Have you tried regular subdivisions? Don't use CC.

Surrealist.
12-31-2015, 06:52 PM
Yeah leave CC's in LightWave as a convenient way to model until you have all quads. After that use Subpatch. There are too many issues with CC's in current LightWave to bother even using them. Hopefully LightWave will get true (or well implemented) CC's and even Open Sudiv soon.

jasonwestmas
12-31-2015, 07:17 PM
Select all subD surfaces in the w panel, hit Tab, switch your default SubD mode to subpatch and hit Tab again to Convert the CCs.

graviel
01-01-2016, 08:43 AM
Thank guys..

But this is a disaster, those models are using edge sharpness, Subpatch rounds everything, CC has edge sharpness ...I cannot use subpatch. This means I will have to model everything again because in order to keep the edges sharp I would need to add geometry.
Using the characters independently it all works just fine, but when I put them in the same scene it just brokes..

Why to implement CC but not finish it? Why is it there in the first place? I come from Maya and Softimage, so I haven't been around long enough to even learn to appreciate Subpatch... to me CC seemed to work just fine, until this bug came over... I tested this method many times, this is just happening at the very end when I brought all the parts together... I do have plenty of scenes alrready rendered, when the number of objects is small it does work.

cannot use subpatch for this, it means redoing the entire thing.. I need to find a workaround this bug...

any other ideas apart from subpatch?

JoePoe
01-01-2016, 10:12 AM
Two ideas.

1) Freeze your models? (be careful, just check on smoothing afterwards)

or

2) No promises here, but...... Way back when (when I gave CCs a shot 8~) I ran, of course, into the "breaking" issue too. So much so that I never really bothered to take them much further into Layout. But, in Modeler I found that when things started falling apart, if I selected all edges and hit Increase (or Decrease) Sharpness things would snap back together... (Not 100% correctly all the time but most of the time.) So, when they break in Layout, with the Hub open, try doing that in Modeler and see if the models update.
Edit: Whichever one you hit (increase or decrease) immediately do the other as well so the net sharpness change is 0.

Edit 2: Just did a quick test. Seems to update fine on CCs that were broken when initially brought in to Layout. Hopefully it'll do the same on those that break in the middle of your scene... for whatever reason (which I didn't try to recreate).

graviel
01-01-2016, 11:01 AM
Thanks Joe,
The first option is doable, so once everything is ready I guess I could just freeze the geometry.

As for the second one, the geometry does refresh indeed.. it doesn't really work if I go object by object, because as long as I affect a different one the others ruin... but I was able to observe a bit better the behavior; whenever I change subdivision order in layout or increase CC sharpness in modeler, the object in question fixes, but all the rest gets ruined. I tried to decrease and increase CC sharpness in modeler to many objects at the same time and when I switched back to layout it almost worked out... it was only 1 object with the error.. I will investigate a bit more.

I guess the solution would be to refresh all objects at once. Maybe..

graviel
01-01-2016, 11:13 AM
Yeah, just select all objects, hit p, change subdivision order to all of them at the same time, e voila... I managed to preview couple of frames correctly... I hope this does it. Thank u guys, i will be back if this workaround happens to stop working...

jeric_synergy
01-01-2016, 12:00 PM
Ugh. Glad you're the one figuring this out, I'd be suicidal by now. :thumbsup:

Ma3rk
01-01-2016, 01:35 PM
If it got down to it, you could use subpatch weight painting. It's a bit hidden and kind of klunky, but it does work to smooth/sharpen subpatches at the point level. You need to have one panel open for weight shade viewing then select the SubPatch Weight tab.

131712 131713

Or, perhaps easier is to simply select the desired points, click the "i" key to bring up the info panel and manually set the weights. You can select multiple points, set value individually or select Edit All and set all to the same weight.

Hope it works out.

Surrealist.
01-01-2016, 02:06 PM
Regarding the questions about CC and why it has not been fully developed I have no idea. Perhaps it is hung up on some limitations in Modeler which is 25 + years old... ;) So we probably won't see any fixes to this until mesh editing comes to Layout with the new Unified Geometry Engine.

I also had a large project with a ton of modeling all committed to CCs about 8-9 years ago. I remember coming into some bug in Layout with Displacements. I don't recall what it was exactly I was specifically doing but the thread is here:

http://forums.newtek.com/showthread.php?64896-Nodes-Normal-Direction-Surface-Displacement

And the end it never sorted. CC supbatches just did not work, no matter what I did. And because the objects had some ngons I had to go back and fix the models to work with Subpatch. That was a pain in the arse.

Then another thing as far as I know is still broken, (just tested and yep seems to be FUBAR in 2015) is you can not turn on Subpacth interpolation of your UVs if you use CC.

So for any serious work with textures, forget it.

I think most people eventually come across some issue or another with CCs.

Until this is absolutely fixed, just don't use them, outside of initially modeling with nGons.Then revert back to Subpatch.

Yeah that is odd it is strange, CCs are far superior.... oh well.

graviel
01-01-2016, 02:54 PM
Well it is kind of annoying to hear since CC has his own permanent button always visible in modeler, it does not look like some experimental command...

Ma3rk, when I started this project I gave a long try to sub patch weights, but for the kind of work I do it would require more effort and CC is more precise, assign sharpness levels per edge becomes a modeling tool on its own.
I was already warned once about CC (dont remember who, maybe Ernest), and I had difficulties mirroring weights, but I figured out how to solve all the other issues (for example CC weights are double sided, so after mirroring you just have to flip the normal).

I have been using endomophs as animation keys, and for that CC is my favorite since I can go with the minimum geometry and still have a mixture of organic and rational shapes which might be painful to do any other way... did not have difficulties with UV maps so far... so, it is not the first time that this gives me headache, but it is the first time that I get into a dead end bug.

But I still somehow find it worth to walk-around this or that headache... lets see, hope I can just finish this thing without incidents.

jeric_synergy
01-01-2016, 03:26 PM
After watching everybody else struggle with them, sometimes 'WAYYYyyyy far into the production process when it hurts most, I've avoided them like I avoid missionaries: religiously. :D

Surrealist.
01-01-2016, 03:33 PM
lol well annoying like everything that has not gotten fixed in years.... Like "Self Collision" button in Cloth FX. Never fixed. Still not fixed. Works in Bullet though.

And now you see why we are so exited to see v2016 coming, not a moment too soon...

I also use Maya and used XSi for a while. I also use Blender. All of these apps have much better implementation of CC's

So my advice is to take LightWave at face value. You have been warned. :D

Use CC's at your own risk. ;)

graviel
01-02-2016, 08:48 AM
yeah.. I see the consequences. You can workaround limitations in the workflow, like the mirroring example, but this kind of bugs are too much of a risk.
So, this has been around for 10 years... not nice, even the blender folks get things sharper sooner.
My experience with LW until this small incident has been so far very positive, considering XSI was put to dead and Maya was soaked in wax. It allowed me to continue working without having to deal with the big A. I do personally like treating local and global spaces separately, so did not have a complaint about modeler itself, but well any effort to get rid of long lasting bugs such as this make sense... I did miss nodal while modeling, and from now on I guess Ill miss CC. Hope they fix it soon.

anyway, very many thanks for all advice.

Surrealist.
01-02-2016, 04:14 PM
So I know this is a controversial subject. But here goes. There is a reason 15 years ago the original LW team started developing a new app from scratch. They left NewTek and what came from that was Modo. And have a look at how long it took them to get to an app that is now fully featured. Meanwhile LightWave was still here and being developed on top of the same old crap code and design decisions that the original team bailed on. Do you get the picture?

And starting about 8 years ago gradually people left LightWave for Maya XSI, Blender etc. Core happened durring all of that.

Skip to the present and the goal of rewriting LW to be a more modern architecture is finally at a place where they replaced the geometry engine in LW Layout and tools can go there for modeling eventually etc.

The moral of the story is, LightWave is grand. It is a great app with lots of wonderful features and workflow.

But take it at face value and don't get upset about these things you run into. Most of it is just things they could not change because of old code and design decisions. That has finally changed for the better.

In the mean time take LightWave at face value enjoy it. It has many benefits.

Ztreem
01-02-2016, 05:33 PM
Just a little tip: if you model with ngons and cc and want quads only to convert to subpatch, freeze the model in cc mode with it set to a low level and it will freeze the model with only quads.

jeric_synergy
01-02-2016, 05:44 PM
Just a little tip: if you model with ngons and cc and want quads only to convert to subpatch, freeze the model in cc mode with it set to a low level and it will freeze the model with only quads.
Is that 100%, or more like "99% quads"? Good tip, either way, just sort of academic interest.

Ztreem
01-03-2016, 07:17 PM
Is that 100%, or more like "99% quads"? Good tip, either way, just sort of academic interest.

I must admit that I don't remember. It may add some tris as well, but it's subpatch friendly(no ngons).

jeric_synergy
01-03-2016, 07:31 PM
I just did a quick check (surprisingly hard to MAKE n-gons after years of avoiding it) had some tris, some n-gons, FROZE it, all quads. Tried with 3 diff levels of CC subd'ing, and all resulted in quads only, so BIG WIN HERE! Thanks for the tip, that is EXCELLENT! :thumbsup:

You should post this over in the BASIC THINGS thread, because I think it's a very valuable technique, and you deserve the credit for it.

Ztreem
01-03-2016, 07:57 PM
I just did a quick check (surprisingly hard to MAKE n-gons after years of avoiding it) had some tris, some n-gons, FROZE it, all quads. Tried with 3 diff levels of CC subd'ing, and all resulted in quads only, so BIG WIN HERE! Thanks for the tip, that is EXCELLENT! :thumbsup:

You should post this over in the BASIC THINGS thread, because I think it's a very valuable technique, and you deserve the credit for it.

I can post it there, but I don't deserve the credit for it. I learned the technique from these forums years ago. :hey: