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Nitisara
10-28-2008, 11:28 PM
When calculating cloth dynamics, cloth disappears after 1st frame of calculation. Only fixed points remain on their places - other cloth polygons just disappear as they never been there.
Animation movement is very slow and simple, there is no excessive stretching, forces etc what could lead to unpredictable or unstable cloth behaviour. There are no colliders, self collision or anything.
Calculation resolution changes makes no difference.

Main cloth parameters are:
Weight=0.2
Spring=100
Viscosity=100
Resistance=1
Sub structure=100
Self structure=1000
Compress stress=100
Stretch limit=10
Polygon size=100

Surrealist.
10-29-2008, 09:15 AM
It may just be a display issue. Does the calculation go through? Also if you have a lot of points that may be it.

Dirk
10-29-2008, 10:55 AM
Could be an issue or wrong settings for the collision object (I use advances object and use an invisible collision object that deformes with the character - "use bones from"). Also, you can try to use the edit tool and see where the dissapearing nodes are, this might give you a hint about whats wrong.

Dirk
10-29-2008, 11:10 AM
Oh, and a self structur of 1000 seems to be much to high.

Self structur can help to deform clothing, since you can tell the cloth to deform with the character when You set the cloth to "use bones from object".

Nitisara
10-29-2008, 02:23 PM
It may just be a display issue. Does the calculation go through? Also if you have a lot of points that may be it.
Yes, calculation goes through, but very fast, because it misses all cloth points except fixed ones.

Could be an issue or wrong settings for the collision object (I use advances object and use an invisible collision object that deformes with the character - "use bones from"). Also, you can try to use the edit tool and see where the dissapearing nodes are, this might give you a hint about whats wrong.
There is no collision object.

erikals
10-29-2008, 02:43 PM
it's not always easy, try to lower the Spring and Viscosity. I've come to that I often have to have to do a lot of testing to get things right.
maybe you could share the scene?

Surrealist.
10-29-2008, 03:12 PM
Yes, calculation goes through, but very fast, because it misses all cloth points except fixed ones.

There is no collision object.

Have you tried deleting the cloth dynamic from the object and starting fresh?

Nitisara
10-29-2008, 11:39 PM
Ok, lowering Viscosity to 10 helped. But the problem was so serious because sometimes these settings worked well, and sometimes - not. Sometimes increasing calculation resolution helped, sometimes - not. Sometimes adding collider affected, sometimes - not. Sometimes collider settings worked well, sometimes - not. So it was very difficult to get what setting should be changed to make it work.

Surrealist.
10-30-2008, 12:35 AM
Cloth Voodoo! I feel your pain.

Dirk has come up with some very good techniques though and there is a cloth thread he started in the Gallery WIP worth looking at. :)

Surrealist.
11-01-2008, 06:50 AM
This actually just happened today. I hit calculate and the object was gone......!!!

Turned out I forgot to set subdivision to last. Don't know if that will help you or not but I thought I'd mention it.

erikals
11-01-2008, 07:41 AM
I've read that scalling the object to a bigger size at times can help as far as speed goes. you might try it, see what happens..