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Julez4001
12-04-2003, 12:54 PM
http://www.flarenova.com/sbd1.jpg


Not necessary a tutorial (but I will do one if its still vague).

This is for everyone who wants to do a character with the skirt

http:\\www.flarenova.com\sbd_skirt2.mpj

** There are two collision proxie spheres:
1 parented to the Thigh and other to the shin.
So you wil have to add more objects for parts you want to collide.

There are some collision rules to SBD clothes in messiah

1. You must add some thickness to your CLOTH model for pressure. Not necessary for SBD effects but for collision - yes!
2 Its better to use collision objects (preferablly spheres but u can make crude replicas of the objects (collision proxies) that will the colliding objects)
a. use radius for edge adjust
b. set your collision radius

3 For lightwavers, Do not use layered objects..create separate objects for body, the cloth and the collision proxy objects
4. Keep replacing objects to a minimal, SBD sometimes use the same deformation information from previous object on ur new object when you replace.
5. Write your sbd settings down
6. sbd is realtime, so it can change from playback to playback
check setting to make sure you get the same repeated performance..sometimes it could be the metanurbs slowing down playback or such.
7. Good starting point for softbody settings SLIDER BAR

Set everything to 0 except for Global weight and Gravity Scale..set them to 1.

SideNotes

Triple objects or proxies to see what changes in dynamics, you may get better results.

Add more polys especially in the bending areas of the cloth.
Higher the poly count, the better deformation but also the slower but there always MetaNurbs :)

Unnecessary uses cloth dynamics:
- Jackets and shirts unless the sleeves or flaps hang
- Capes and hanging cloth shouldn't solely use SBD - use bones as well and you have more control. Add SBD after bone animation, think about using PointOven. By this I mean ..
do you animation with just bones and then save teh deformation and apply sbd via messiah or third party (maya syflex or lw MD)..whatever you do apply sbd after main deformations.

---------------------------------------------------------------

FTM:

Key: Moves through the existing keyframe numbers. Enter a number in the entry field to go to a specific key or use the arrows to scroll through. Note: This is not referring to the frame number, but rather whether it's the first keyframe, second keyframe, etc. For example, the first keyframe might be on frame 0, and the second keyframe might be on frame 65.

Frame: Displays the frame number that a keyframe is on. Also, you can type a number in here to change the actual frame that a keyframe is on. For example, lets say you have keyframe #2 and it's on frame 33. Just type in 52 and now keyframe #2 will be on frame 52. It's a really fast way to accurately move a keyframe.

Fluid Density: Sets the density of the atmosphere that the object is moving through. For example, you can set this to be thick, like water, or thin like air. The higher the number, the "thicker" the atmosphere.

Damping: Sets the damping of the movement-- how quickly it stops jiggling or waving, or whatever.

Global Weight: The weight of the points in the object. A positive number will make it weigh more, a negative weights will make it float.

Internal Pressure: An imaginary force that comes from within the object that pushes out toward the surface normals of the points. Picture a hot air balloon: a gust of wind will push in and deform it, but the pressure of the hot air inside the balloon pushes it back out into its original shape.

Gravity Scale: A multiplier for gravity. The default gravity in messiah is set for real gravity. If you need it more intense or less intense, use this setting.

Spring Damping: This dampens the reaction to compression and stretch.

tangledpath
12-04-2003, 03:25 PM
This looks awesome. I'll defintely be looking into this when my copy of studio arrives.

Question, why does the model need to have thickness and what does this mean exactly? Also, if collision spheres are being used, why would the model need to have thickness? Or do you mean the skirt model?

This rocks :buttrock:

Julez4001
12-04-2003, 03:56 PM
the skirt model has to have thickness, i correct that.

Thickness ... helps the model behave like you think it will and this is for collision reference, you don't have touse it but i ind that the cloth just pops all of the place even with a nice global weight setting.

chikega
12-05-2003, 03:04 AM
Thanks, Julian - nice info there:beer:

bradenbickle
09-08-2004, 06:07 AM
I would love to see one from beginning to end. Step one, launch Messiah and so on and so forth. I'm not much of a newbie anymore but it is still a little mind boggling as to how the dynamics work.

Also, could you post an fxs file with the lwo file as well?

I've tried to play around with the file and even swap out geometry just to see what would happen and nothing happened at all.

bradenbickle
09-08-2004, 06:07 AM
Also, have you tried this method with guide chains? That would be cool to see.

Julez4001
09-08-2004, 03:40 PM
Works with guide chain as well.

Use a crude sphere as your collision object and not he head itself.
Like noted above, keep the 'replacing object" to a minimum. You will usually have to replace (remove effect and reapply) the sbd effects if you replace the object as it uses the old info on the vertex (point) count to determine deformation.

Actualy MotionDynamics would be better or a combinationof the two.

bradenbickle
09-08-2004, 04:42 PM
I have a theory I was thinking about trying, but wanted to see if you have already gone down this road.

What if I put some bones in the bottom of the head and applied Lazy bones to them, and then used a spherize effect to force the mesh away from the shoulders?

Just a thought as an alternative.

bradenbickle
09-08-2004, 04:42 PM
Correction:

Bones in the bottom of the hair, not the head

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