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gamedesign1
04-04-2016, 11:08 AM
Hi All

I am having a bit of trouble getting cloth to move from a rigged mesh.
I have one layer which is the rigged mesh and another layer which is the clothes mesh.
The rigged mesh is set to kinematic and the clothes mesh is set to deforming.
The rigged mesh moves great with the genoma bones, but the cloth is not recognizing the deformed mesh, it just hangs on to the original position of the rigged mesh and doesn't move when i move the bones.

Any thoughts?

CaptainMarlowe
04-04-2016, 12:20 PM
The rigged mesh must be a deforming one with 100% Shape retention and translation and rotation locked. This is documented in the manual, I believe (can't check right now).

prometheus
04-04-2016, 01:25 PM
You could also have forgotten to set the deforming cloth subdivision to last or after displacement in the object subdivision settings, if you have it set to first it will not work.

gamedesign1
04-04-2016, 01:36 PM
I have done that and my model just wants to fall with the gravity then. Not sure how to stop that. OK I stopped it falling with gravity when i set it to locked translation and rotation.
But now the arm is bubbling like its reacting to gravity and the other mesh :( Also the calculations are really slow now, its just not manageable. hmmmm....

gamedesign1
04-04-2016, 01:47 PM
Maybe cloth simulation just isn't in my reach with this machine

gamedesign1
04-04-2016, 02:06 PM
how do i stop the rigged mesh being affected by the clothes mesh?

gamedesign1
04-04-2016, 02:13 PM
By setting the clothes mesh to deforming it seems like it is having to do a load of unnecessary calculations as it interacts with the rigged mesh. surely the rigged mesh should only be thinking about how it deforms based on the bones that it is rigged with. But by setting it to deforming it is also looking at what the the clothes mesh is doing.

prometheus
04-04-2016, 03:15 PM
I have done that and my model just wants to fall with the gravity then. Not sure how to stop that. OK I stopped it falling with gravity when i set it to locked translation and rotation.
But now the arm is bubbling like its reacting to gravity and the other mesh :( Also the calculations are really slow now, its just not manageable. hmmmm....

I am unfortunatly no expert myself on bullet softody and cloth situations and rigged character, been messing with some other bullet deforming stuff though.

Of course the model will fall ...thatīs what is happening if you drop a cloth in the air without nothing to hold it in real life as well:D

You need another item to hold it up, for instance you could add nulls and make them kinematic I think ..or use simple box object as kinematic..make sure it covers the end part..like if you had a superman cloak ..the parts that are on the shoulder needs to be within or enclosed by the kinematic object, you can move the kinematic object around and that would move the cloak as well.
so if you had a setup with nulls parented to bones, and the null had the same hiearchy as I described above..it might work.

You could also set up the same but both the kinamatic parented to a null object that isnīt a dynamic object ..so even if you move the null object without any dynamics itīs child dynamic will move, and consequently also the deforming cloak cloth..even though the cloth isnīt parented to any of those.

Maybe start with such simple samples, then continue with rigs?
2015 has hinges and other items that may work..though I havenīt tried it out.

Good luck and share what you find.

prometheus
04-04-2016, 03:31 PM
simple sample...

prometheus
04-04-2016, 04:32 PM
Making bones themself kinematic should work to ...at least in lw 2015.

gamedesign1
04-04-2016, 09:19 PM
I am unfortunatly no expert myself on bullet softody and cloth situations and rigged character, been messing with some other bullet deforming stuff though.

Of course the model will fall ...thatīs what is happening if you drop a cloth in the air without nothing to hold it in real life as well:D

You need another item to hold it up, for instance you could add nulls and make them kinematic I think ..or use simple box object as kinematic..make sure it covers the end part..like if you had a superman cloak ..the parts that are on the shoulder needs to be within or enclosed by the kinematic object, you can move the kinematic object around and that would move the cloak as well.
so if you had a setup with nulls parented to bones, and the null had the same hiearchy as I described above..it might work.

You could also set up the same but both the kinamatic parented to a null object that isnīt a dynamic object ..so even if you move the null object without any dynamics itīs child dynamic will move, and consequently also the deforming cloak cloth..even though the cloth isnīt parented to any of those.

Maybe start with such simple samples, then continue with rigs?
2015 has hinges and other items that may work..though I havenīt tried it out.

Good luck and share what you find.

Thanks for replying, I'm not trying to stop the cloth from falling, it's the rigged mesh that I don't want to fall. The rigged mesh is the body inside the clothes. I will take a look at that zip tomorrow when I'm at my pc :)

lightscape
04-04-2016, 10:36 PM
You should use a very low poly version of your rigged mesh or just primitives parented to its bones as collision for your cloth sim.

prometheus
04-04-2016, 11:29 PM
Thanks for replying, I'm not trying to stop the cloth from falling, it's the rigged mesh that I don't want to fall. The rigged mesh is the body inside the clothes. I will take a look at that zip tomorrow when I'm at my pc :)

if the character is entirely a deforming body, it will fall as well, guess you need to support it with kinematics..by bones maybe that are kinematic, or make the whole body kinematic..maybe it can work if you baked mdd and use that as kinematic full body, not sure about that.

Thomas Leitner
04-05-2016, 12:22 AM
By setting the clothes mesh to deforming it seems like it is having to do a load of unnecessary calculations as it interacts with the rigged mesh. surely the rigged mesh should only be thinking about how it deforms based on the bones that it is rigged with. But by setting it to deforming it is also looking at what the the clothes mesh is doing.

Hi, as CaptainMarlowe said:
If you want to maintain the original shape of the deformed object, you need to set some parameters in the Bullet Softbodies panel:
• Shape Retention must be set to 100%
• Shape Lock must be set to Translation & Rotation
• Both Linear and Angular Stiffness must be set to 0
• Volume Conservation must be set to 0.
(Manual, page 818)

And donīt forget:
Make sure you set the Subdivision Order to After Displacement or Last for any Deforming Body subpatch objects or they will not work.
(Manual, page 815)

ciao
Thomas

gamedesign1
04-05-2016, 09:05 AM
Hi, as CaptainMarlowe said:
If you want to maintain the original shape of the deformed object, you need to set some parameters in the Bullet Softbodies panel:
• Shape Retention must be set to 100%
• Shape Lock must be set to Translation & Rotation
• Both Linear and Angular Stiffness must be set to 0
• Volume Conservation must be set to 0.
(Manual, page 818)

And donīt forget:
Make sure you set the Subdivision Order to After Displacement or Last for any Deforming Body subpatch objects or they will not work.
(Manual, page 815)

ciao
Thomas

Thanks, got that all working now :)

gamedesign1
04-05-2016, 09:07 AM
You should use a very low poly version of your rigged mesh or just primitives parented to its bones as collision for your cloth sim.

I have done what you have suggested and used a low poly mesh as the collision object, which works great.
If I used a low poly mesh as well for the cloth, is there a way of getting a high res mesh to roughly follow a low poly mesh?

When using the old FX_Cloth plugins you could use a FX_Metalink plugin to get it to follow the parent mesh deformations. But the FX_Metalink obviously only works with FX_Cloth. I just wondered if there was a way of doing the same thing with Bullet.

Thomas Leitner
04-05-2016, 10:01 AM
I have done what you have suggested and used a low poly mesh as the collision object, which works great.
If I used a low poly mesh as well for the cloth, is there a way of getting a high res mesh to roughly follow a low poly mesh?

When using the old FX_Cloth plugins you could use a FX_Metalink plugin to get it to follow the parent mesh deformations. But the FX_Metalink obviously only works with FX_Cloth. I just wondered if there was a way of doing the same thing with Bullet.

Yes,
you can use the same method. Apply ClothFX. Donīt change any settings. Scan motion. Deactivate bullet. Use Metalink as usual.

ciao
Thomas

gamedesign1
04-05-2016, 10:31 AM
Yes,
you can use the same method. Apply ClothFX. Donīt change any settings. Scan motion. Deactivate bullet. Use Metalink as usual.

ciao
Thomas

I find ClothFX really fiddly to use and difficult to get the results i want. Is there anyway I can use Bullet for this?

prometheus
04-05-2016, 02:48 PM
I find ClothFX really fiddly to use and difficult to get the results i want. Is there anyway I can use Bullet for this?


I thought he just ment scan the bullet deforming body with clothfx, thatīs not difficult at all, just add clothfx on the object and scan the modion, once done you got direct replay of the mdd if you need, or can set the mdd up to work with metalink with nodes etc.

gamedesign1
04-07-2016, 04:42 PM
That's great I didn't realize that ClothFX could scan motion. I have always used MD Baker for that. Thanks for your help guys!