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Andy Webb
11-05-2018, 11:12 AM
I'm testing a flag with wind FX.

My problem is I have a point selection set down one side as a fixed group and the flag works as expected,
but as soon as I turn subpatch on the fixed side (point selection set) no longer has an affect, the flag just blows around all over the place.

Any thoughts why?

Cheers

erikals
11-05-2018, 11:28 AM
not quite sure, perhaps take a look at this scene...

download > http://forums.newtek.com/attachment.php?attachmentid=83364&d=1269295836

11-05-2018, 11:54 AM
Subdivision might need to be last.

prometheus
11-05-2018, 01:08 PM
Subdivision might need to be last.

Itīs not necessary, it should work with it set to first, it is probably something related to the created fixed points, clear map, select again and make a new fixed pointset, try again with default clothfx settings.

prometheus
11-05-2018, 02:00 PM
I'm testing a flag with wind FX.

My problem is I have a point selection set down one side as a fixed group and the flag works as expected,
but as soon as I turn subpatch on the fixed side (point selection set) no longer has an affect, the flag just blows around all over the place.

Any thoughts why?

Cheers

nevermind, I missed that you missed a word between subpatch, or a comma.

Cloth flags can be so delicate in fabric, that a subpatch level of last isnīt good enough in my opinion to catch all the details, for that you would probably like to have it set to first..same principles as making waves.

Andy Webb
11-05-2018, 04:41 PM
nevermind, I missed that you missed a word between subpatch, or a comma.

Cloth flags can be so delicate in fabric, that a subpatch level of last isnīt good enough in my opinion to catch all the details, for that you would probably like to have it set to first..same principles as making waves.

Now can someone tell me where you set subdivision order in 2018, I just cannot find it, it seems to have moved from the previouse version.

Andy Webb
11-05-2018, 04:50 PM
Never mind, I just realised how to do it, moving subdivision to after cloth FX.

Any way that worked and thanks for you guys help.

prometheus
11-06-2018, 01:35 AM
Never mind, I just realised how to do it, moving subdivision to after cloth FX.

Any way that worked and thanks for you guys help.

You shouldnīt have to set it to subdivision last, something is wrong in 2018 if that is required, besides..you may loose out on cloth folding detail when using subdivision last, it depends on..it can help using a lot of initial divisions before you set it to last.

Andy Webb
11-06-2018, 03:18 AM
You shouldnīt have to set it to subdivision last, something is wrong in 2018 if that is required, besides..you may loose out on cloth folding detail when using subdivision last, it depends on..it can help using a lot of initial divisions before you set it to last.

Well it worked and before I set it to last it was appalling, fixing edges just completely failed :(

prometheus
11-06-2018, 12:28 PM
Well it worked and before I set it to last it was appalling, fixing edges just completely failed :(

Just keep in mind to give the flag enough main divisions in modeler before you subpatch it and raise subpatch levels, and keep subpatch levels low ..if you do so and use subdivisions set to last, you can get
good enough detail while using clothfxm this is a bit of the opposite to having low Main divisions, and raising subpatch levels and use subpatch set to first.

jwiede
11-06-2018, 07:20 PM
fixing edges just completely failed :(

Were you using ClothFX or Bullet SBD?

prometheus
11-07-2018, 07:23 AM
Were you using ClothFX or Bullet SBD?

I think we should assume it is legacy clothfx.
Hw mentions that..and if i recall it right..bullet dont use fixed point sets.

Greenlaw
11-07-2018, 01:39 PM
Just curious but why use ClothFX for this? Bullet is faster and works great for flag effects. (I've used it for flag effects in a few movies.) ClothFX may still have a few uses but I pretty much stopped using it several years ago in favor of Bullet, especially for fairly simple cloth dynamic fx like a flag.

The trick with Bullet is you want to have enough real polygons in the mesh for credible folds and wrinkles. You can still use subpatch with the object but the Bullet calculations are performed on the base shape vertices, not the subpatched vertices. I know in general, many LightWavers want to model with as few polygons as possible, but this is a situation where more polygons can be better and more accurate. And it will still be faster than ClothFX.

Hope this helps and good luck!

prometheus
11-08-2018, 05:45 AM
Just curious but why use ClothFX for this? Bullet is faster and works great for flag effects. (I've used it for flag effects in a few movies.) ClothFX may still have a few uses but I pretty much stopped using it several years ago in favor of Bullet, especially for fairly simple cloth dynamic fx like a flag.

The trick with Bullet is you want to have enough real polygons in the mesh for credible folds and wrinkles. You can still use subpatch with the object but the Bullet calculations are performed on the base shape vertices, not the subpatched vertices. I know in general, many LightWavers want to model with as few polygons as possible, but this is a situation where more polygons can be better and more accurate. And it will still be faster than ClothFX.

Hope this helps and good luck!

I may not have worked with bullet to such extent that I could make good flag effect, after your advice I will take a look at that again..but to what I found out the short time I tried it, I didnīt like the result for trying to simulate cloth, as you said and it may be similar to using high amount of initial polys before subpatch to last in cloth fx...using more polys initially is crucial.

otherwise I like the clothfx results better, but will have a stab at it, by the way..do you have a rendered sample or an opengl preview to see the results you think is better with bullet?

Greenlaw
11-08-2018, 09:58 AM
...otherwise I like the clothfx results better, but will have a stab at it, by the way..do you have a rendered sample or an opengl preview to see the results you think is better with bullet?

There are a couple of shots of a flag on my old 'Asylum' demo reel. (http://littlegreendog.com/2017/03/23/asylum-vfx-demo-reel-2015/) I've created flags and banners in a few other situations but this is probably where a flag is featured more prominently. Scrub to around 2:36 or so for the first one; the second follows a few shots later (I think the first clip shows more detail though.) This entire scene knocked out pretty quickly because I only had a couple of days to design, assemble, animate (thank goodness for iPi Mocap Studio!) and composite both shots. Considering the tight schedule, I think it turned out pretty decently. BTW, this was also the first time I tried Bullet Bone Dynamics in LightWave. I used the constraint for the cable dragging the flag. At the time, LightWave 2015 was still in beta and bone dynamics was a little buggy, but it still got the job done. (I believe the bugs have been since fixed.)

I poked around my test album on Vimeo and found some old but interesting Bullet examples. These aren't meant to be perfect effects, they were just quick tests I created to demo some features:

A while back somebody in the forums asked about getting details in Bullet cloth, so I threw together this simple example to illustrate the different qualities I get with higher polygon density:

FlagResComparisons (https://vimeo.com/142009369/3e4271aeaa)

The interesting thing about this example is that my 'high res' flag is actually lower res than the sub-patch model, but shows more detail in the simulation. This is because of what I mentioned in the earlier post.

If you need even more wrinkles, you can use more polys and maybe add some 'cross wind' to the wind effect. Oh, almost forgot: It's important that the polygons are roughly the same size. If they vary too much, the dynamics can get less realistic. (Generally true in many 'fast' dynamics programs.)

Here's another simple example I threw together when somebody in the forums said that Bullet cloth couldn't create enough detail for a realistic skirt animation:

‘Quick and Dirty’ Bullet Cloth Test (https://vimeo.com/142006826/8fc3451d53)

The 'Sister' animation was something I already created in Brudders R&D, and it took me maybe a half hour to add the skirt and apply Bullet to it.

This next Bullet test isn't very 'flag-like' but it shows how more polygons can allow nice folds to occur in bending joints:

LightWave Bullet Cloth Folds Test (https://vimeo.com/234184917/6bed0e4d37)

It also illustrates how quickly Bullet calculates a simulation when it's set up for efficiency. Years ago, when the only choice was ClothFX, this sim would have taken me an hour or more. Generally, my work schedules didn't allow for that so I would wind up using using a cage object...but then the folds were not as realistic either. (But it would get done on time, which was always more important.) :)

Hope this helps

prometheus
11-08-2018, 10:42 AM
Hope this helps

Except your demo reel....The links are not working, I know that vimeo as of latest years.. have screwed this up somehow, linking to youtube is working to embedd in these forums..but not vimeo.

And yes..the flag behind the aeroplane is looking good, but you see..the thing is that it doesnīt fold over itself very much, so that effect I know I could get with bullet fx,
itīs when the wind is dropping rapidly..then picking up force again that you may see a flag fold overlap a bit..itīs not present in the reel.

Unfortunately I can not verify if you had something that shows this in the other links...sadly broken.

I Will put up a sample of what I mean about more detailed cloth folding of the flag in the weekend, dog tired and have to jump in to bed to manage tomorrows work.

Check those links..check those links :)

Greenlaw
11-08-2018, 10:45 AM
That's really weird...all the links are working here. The first one goes to my website, the rest go directly to the Vimeo website.

If anybody else here can check, please do.

I'll check the privacy settings for the videos.

Edit 1: Ok, I'm back. The privacy setting on two of the links didn't include this domain. I set these to work 'anywhere'. The other two should have been ok.

Edit 2: Actually, I don't think that should have made any difference since I'm not embedding the videos here. These videos at Vimeo are all set to allow anybody to view, so the links really should work here.

prometheus
11-08-2018, 10:47 AM
That's really weird...all the links are working here. The first one goes to my website, the rest go directly to the vimeo site.

I'll check the privacy settings.

If anybody else here can check, please do.

log out and use this forum as a guest and try the links.
perhaps also clear browser cache before doing so.

prometheus
11-08-2018, 10:53 AM
I can not find any of those videos on your main vimeo page, only some reels and other stuff, so I think they are not public..not listed or something.

Can only get your demo reel to work when clicking on any of the links, I think you need to re-paste the new links to those vids you change settings for.

Greenlaw
11-08-2018, 10:58 AM
A-ha! Thanks. I logged out of Vimeo, and you're right, I can't link to the videos from here. I think the links are okay but something must be funny about the privacy settings. I'll look at it again later.

BTW, you won't find them searching on Vimeo. That's been disabled except as direct links since I don't want a zillion test videos appearing in our public channels.

As for the flag folding against itself, that's just a matter of turning on self-collision. The same would be true if you're using ClothFX. I obviously didn't need it in that example, and I usually leave it off unless it's absolutely necessary. (Time, money, blah, blah, blah...)

I'll see if I can dig up an example with self-collision. The shirt example in the last link (which isn't showing up yet) has folding but it doesn't really have self-collision, it just looks like it does.

Greenlaw
11-08-2018, 11:18 AM
Ok, they should be working now. I had to make everything a private link to work from here.

Thanks for helping me sort that out. :)

Regarding the Newtek forum's inline videos feature, yeah, this seems have been broken for Vimeo for a while now. YouTube still works, as you noted.

prometheus
11-08-2018, 11:28 AM
Ok, they should be working now. I had to make everything a private link to work from here.

Thanks for helping me sort that out. :)

Regarding the LightWave forum's inline videos, yeah, this feature seems have been broken for Vimeo for a while; YouTube still works, as you noted.

Great..all links working now.
Good samples, it still isnīt quite the detailed flag or cloth fold I am refering to, you have some good folds in the brudder character for cloth, but that is more standard cloth, imagine very thin flag or silk style...I will try and render something this weekend ..as well as trying out the same with bullet to compare clothfx and bullet.

Flags can of course be of various materials, thinner silk like cloth and you got it folding with wrinkles quite detailed.

Regarding Vimeo...I think someone needs to notify the Vimeo guys that it is problematic to link/ embedd videos from their site, as opposed to Youtube.

Greenlaw
11-08-2018, 11:33 AM
Regarding Vimeo...I think someone needs to notify the Vimeo guys that it is problematic to link/ embedd videos from their site, as opposed to Youtube.

I don't think it's a Vimeo problem. I can embed videos from Vimeo to other forums and to my own website just fine. It's only here where it seems broken.

Probably should report this to Newtek's support.

prometheus
11-08-2018, 11:44 AM
I don't think it's a Vimeo problem. I can embed videos from Vimeo to other forums and to my own website just fine. It's only here where it seems broken.

Probably should report this to Newtek's support.

That could of course be the case.

Hitting the sack for now, back at the weekend for checking more clothFX and bullet flags.

erikals
11-08-2018, 06:00 PM
i still prefer the look of ClothFX for simpler simulations,
having said that, neither Bullet or ClothFX is perfect, both of them are alright for their use.
both have cons/pros.