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ranhell
02-01-2013, 10:24 PM
Trying out 11.5 bullet cloth Sims interesting setup with bullet definitely will have to be a new work flow for cloth dynamics for me….

http://www.youtube.com/watch?v=10aq3UQ7vnk

Surrealist.
02-01-2013, 11:07 PM
I don't have the 11.5 interface or manual in front of me, but what that looks like is that you need to adjust your collision distance from the body. Once the cloth intersects a collision object the sim will loose it. That is the basic place to be starting when setting up your objects. Make sure that they have enough distance to keep from intersecting. That is just my first impression and where I'd try and look for a solution without knowing anything else about the parameters.

erikals
02-02-2013, 02:26 AM
my guess too...

i'm curious to see if anyone can get rid of the "rubber feel" of Bullet-Soft though...

OnlineRender
02-02-2013, 02:32 AM
I can but I cant post it here :) essentially its to do with the linear stiffness and how much retention of the mesh you keep also weight maps help

ranhell
02-02-2013, 07:25 PM
this is my first try with bullet cloth I have not looked at the manual yet linear stiffness does loosen up the cloth quite a bit it still has a rubber spring to it I will have to actually read what the settings do in the manual...as of right now the default distance settings are just fine. Thanks for checking it out guys....

hrgiger
02-02-2013, 07:37 PM
Forget the cloth, what the hell happened to her head?

hrgiger
02-02-2013, 07:40 PM
What is the geometry like in the dress? I find it works best with equally sized quads if possible. Here is a test I did the other day:


http://www.youtube.com/watch?v=6-qAER1W9Ko

Surrealist.
02-02-2013, 09:16 PM
[
as of right now the default distance settings are just fine.


But wait a minute. You're dress is penetrating the leg. How can the default distances be correct? That is the first sign of collision distance problems. (or quality settings) This is true with Syflex, nCloth, LightWave (original) cloth, Blender Cloth. In nCloth for example they have great visual cues set up for just this problem. And I am willing to be you that this is also true in Bullet softbody. It is just the nature of the beast.

111025

Image for illustration. Basically, there is a reason that feature is there in nCloth and a reason it is a visual feedback for both the cloth object, the collision object and for Self Collisions on the Cloth Object. You adjust the distance and the yellow spheres enlarge or deflate to show you the distance. This is the very first thing to check and it is dependent on the scene scale so this can be widely variable.

The next thing to check (after your distance actually is fine) is the quality setting. Basically that will be how many iterations per frame it is calculating. Not sure where that is in Bullet but it is sure to be there. If it is not making enough calculations per frame it can be off on collisions.

Next after these two would be the actual cloth attributes like stretch (how closely it holds to the actual poly shape) and so on.

Just want to drive home that these things are the basics for cloth sims.

@hrgiger.

Nice sim. I wonder if you can tie metalink to this so that you can drive another object with the cloth sim using Bullet?

ranhell
02-02-2013, 10:09 PM
hey hrgiger nice sim. i completely understand what you are saying Surrealist.
my issue is my collison obj not the cloth take a close look at my image
111026
the geometry collapses on its self I think i have this fixed now....

Never adjusted the collision distance as the cloth gets better...however I just might have to as I get the cloth to loosen up from its rubber feel the obj penetrates the cloth....

http://www.youtube.com/watch?v=sWoN6rVTaPQ&feature=youtu.be

Surrealist.
02-02-2013, 11:30 PM
Looks like you have it penetrating the leg still. Also it kinda looks like there is a lot of friction.

Remember something very simple. It is not a distance that seems correct from real world standards. It is based on what simulates realistically. The closer the cloth object is to collision object, the greater chance of penetration. Because it is all about accuracy. Once it fails to determine where to collide it penetrates. And since it is still trying to collide it will start colliding with the inside and stick. That is what you have there near the end, you can see it inside the leg.

erikals
02-02-2013, 11:43 PM
could also be a sub-structure / hold-structure / stretch limit thing.
or mm accuracy, if such exists in bullet...

JBT27
02-03-2013, 10:15 AM
Two hours ago, I thought I'd just do a quick drop a sheet of cloth onto a shallow cube thing, but I've only just got it anything like plausible, though the rubber effect is apparent. Samples turned up from the default 6 to 100, the collision distance increased beyond anything that makes sense to the real scale, but works for the scene. Change one thing and the collision distance has to be changed again because of penetration. In one run, once the cloth slid off the cube, it increased along its local Z to several times its original length. I haven't yet managed to get anything that feels zero rubbery. But I'm saying all this is me and newness. Someone is going to do well out of tutorials and presets, come the day - need to sit down and test this one alot to make sense of it.

Julian.

Wade
02-03-2013, 10:33 AM
Reminds me a little of the "making of the incredibles" on DVD 2 Everything from the cloth to the hair going off on its own was part of the processes for them in the making of that movie. So for someone new to cloth and such you are right on track keep at it.

ranhell
02-04-2013, 06:44 PM
Ok back to basics

http://www.youtube.com/watch?v=f9Aq22mZZWg&feature=youtu.be

Surrealist.
02-04-2013, 09:00 PM
Interesting, looks like it actually has self collisions. Is there a way to key frame any of the parameters at all?

taimoor
02-05-2013, 02:54 AM
Hey guys!
I tried cloth dynamics like just simply wrap the cloth around a dummy character it works fine even if I move my mesh manually by keyframing. But the problem happened when I rigged that dummy character with bones and applied weight maps and animated the character somehow the cloth on top of this character is not reacting the animated mesh. so how do I need to make it work with a character animated using bones?

ranhell
02-05-2013, 10:29 AM
Surrealist I think you do most of the parameters have envelope buttons next to them
im happy with the look now its time to face fiberfx.....

ranhell
02-05-2013, 11:52 AM
taimoor here are all the setting for the collision obj

111150

Greenlaw
02-05-2013, 03:17 PM
Nice! :)

Surrealist.
02-06-2013, 03:02 AM
Hey guys!
I tried cloth dynamics like just simply wrap the cloth around a dummy character it works fine even if I move my mesh manually by keyframing. But the problem happened when I rigged that dummy character with bones and applied weight maps and animated the character somehow the cloth on top of this character is not reacting the animated mesh. so how do I need to make it work with a character animated using bones?

I don't know what the particulars are in Bullet. It kind of sounds, though like you did not have any dynamics going before that.

But in general you would fix certain points (weight map etc) to the bones. To do this you chose "use bones from" on the cloth object and it will follow the bones. You can use bone influence or weight maps but the fix points need to be the ones you don't want to move other than with for example the waist of hips.

The unfixed points will follow dynamics.

lino.grandi
02-07-2013, 05:12 AM
You can find several cloth samples in the 11.5 content! My advice is to take a look at them! ;)