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jasonwestmas
03-11-2012, 02:03 PM
Has anyone here been involved with any effects that include exploding rigs or ragdolls that fall apart dynamically? I'm having trouble finding information on that. This may or may not include bones and joints.

jasonwestmas
03-11-2012, 05:01 PM
Toward the end the destruction dynamics are applied. I gotta figure out how to do that!

http://www.youtube.com/watch?v=SrctNgySC48

Surrealist.
03-12-2012, 06:10 AM
I know you can do this very straight forward in Softimage. You can have a dynamic get its force from the animation and start at a specified frame.

In LightWave you might be able to come up with a trick but I am not sure how elegant it would be.

I think I saw it demonstrated in this series:

http://www.digitaltutors.com/11/training.php?pid=378&autoplay=1

For a rig I think you could keyframe the constraints to have the dynamics take over. Not sure exactly how you'd set it all up but I am sure it is possible.

In LightWave my first thought is something like freeze transformed and apply the dynamics from a given frame forward with the trans objects in place. Something like that. So basically you'd key the rig out of the render on frame say 200 and on 201 key in the static trrans objects in with dynamics starting on that frame. Could even be done in two scenes. Lots of ideas to play with there.

jasonwestmas
03-12-2012, 09:40 AM
In LightWave my first thought is something like freeze transformed and apply the dynamics from a given frame forward with the trans objects in place. Something like that. So basically you'd key the rig out of the render on frame say 200 and on 201 key in the static trrans objects in with dynamics starting on that frame. Could even be done in two scenes. Lots of ideas to play with there.

gosh, not sure why I didn't think of that, that's a great idea and straight forward.

I'll check out the softimage solution as well.

Thanks!

jasonwestmas
03-12-2012, 10:39 AM
I think what I can do also is after the dynamics blow off an arm or whatever. I can freeze the remaining mesh and apply it back onto the original rig and then continue animating the limbless robot few frames later and let the bullet animation continue it's cached calculations. Not for sure on that but I'll give a whirl.

Surrealist.
03-12-2012, 01:07 PM
Interesting. Hoping you can post some results. Would be cool to see. :)

Actually, thinking about it... you would only have to freeze the arm or whatever gets blown off right? So in effect you could have two scenes or rigs. One pre dynamics and one post. Something like that?

erikals
03-12-2012, 02:59 PM
you could also use a clip map to hide / reveal the two arms. (so no need for 2 scenes)
might give you some motion blur benefits during post work.

(does bullet have start by collision btw?)

jasonwestmas
03-12-2012, 03:18 PM
(does bullet have start by collision btw?)

not sure what you mean exactly.

erikals
03-12-2012, 03:34 PM
hardfx has a "start by collision" feature, so was wondering if bullet has the same
hardfx however has certain issues (lack of accuracy)

looks like it might... (?)

Initial Activation:
- Start Active:
- Start Sleeping:
- Always Active:
 

RebelHill
03-12-2012, 03:59 PM
Bullet doesnt care if a dynamic item has a parent right?? Meaning, if the parent keeps on moving, the bullet controlled child just keeps on as if it had been "broken" from its parent... no?

If so, why not just use a regular ol bone/null rig, parent the robo parts to the appropriate parts, and let bullet blow them off.

jasonwestmas
03-12-2012, 04:31 PM
I was told that bullet doesn't respect any of LW's "tools". But I shall find out. Thanks for the suggestions.

Surrealist.
03-12-2012, 05:41 PM
Jason, i have to apologize. I was completely thinking about the old dynamics. I have not even looked at Bullet yet. But here is a simple test. Very simple to set up in LW 11 Bullet. Set to Activate by last key. Not sure how it will work with bones but it works with objects that are keyed. It will take the last key and use the inertia of the animation to fling the object off into space. Only thing you'd have to make sure is that you have a keyframe for the object on the frame it gets hit. In that case it would likely follow the collision which would be a stronger force of course. So you'll have to experiment. But I am sure you can get what you want from LW Bullet. man... just been focusing on other things lately. Sorry.

And there is probably an even more elegant way in the old dynamics such as start by event or collision... having a slow metal process day, I think.

But here it is in Bullet:

jasonwestmas
03-12-2012, 06:56 PM
very cool Surrealist. If I don't get the bones or joints to work with it I can certainly FK stuff like toy story style.

RebelHill
03-12-2012, 06:59 PM
doesnt have to be bones though... U could build the rig out of nulls.... or cameras.

jasonwestmas
03-12-2012, 07:22 PM
doesnt have to be bones though... U could build the rig out of nulls.... or cameras.

Roger that, I'm working on a little test box-man atm.

jasonwestmas
03-13-2012, 11:57 AM
Ok, here it is. Though it technically works, the IK chain in the right leg gets wonky after I apply bullet to the objects in parts mode. Hmm, maybe I need to apply parts mode to the nulls too. I'll try that.

jasonwestmas
03-13-2012, 03:45 PM
Ah ok, Baking the entire leg including the goal objects fixes the IK instability when using "Parts". I have to do more testing to be sure though.

Surrealist.
03-13-2012, 04:01 PM
That's odd.

Does anyone know where these two items are?

Where do yo save and manage dynamics cache files?

How do yo tell dynamics when to start?

I mean a key-able global switch. Or even allow you to set a key range.

I don't see this in the interface. Is it hidden someplace?

As far as this particular problem. That is real strange that you have these items set to start by last frame and they are going wonky.

A simple global switch to turn Bullet on or off by a keyframe would be a good feature.

Other workarounds would take longer, but I would lean more toward simply having two rigs one with and one without dynamics. Pop on in and one out kind of thing. This would give you the freedom to rig how you want.

Also a more complex scene set up like we discussed earlier would allow for bones.

Interesting to see what you come up with for a solution.

EDIT: OK saw your fix to bake the animation. Interesting. Still that is kind of an odd workaround. But if that works so be it. Seems that Bullet is missing key elements of control in this release. Unless I missed it. Hope NT has plans to upgrade the interface to add more needed control.

What you should be able to do is have the Dynamics start and end within a key range within the scene.

jasonwestmas
03-13-2012, 04:57 PM
That's odd.

Does anyone know where these two items are?

Where do yo save and manage dynamics cache files?

How do yo tell dynamics when to start?

I mean a key-able global switch. Or even allow you to set a key range.

I don't see this in the interface. Is it hidden someplace?

As far as this particular problem. That is real strange that you have these items set to start by last frame and they are going wonky.

A simple global switch to turn Bullet on or off by a keyframe would be a good feature.

Other workarounds would take longer, but I would lean more toward simply having two rigs one with and one without dynamics. Pop on in and one out kind of thing. This would give you the freedom to rig how you want.

Also a more complex scene set up like we discussed earlier would allow for bones.

Interesting to see what you come up with for a solution.

EDIT: OK saw your fix to bake the animation. Interesting. Still that is kind of an odd workaround. But if that works so be it. Seems that Bullet is missing key elements of control in this release. Unless I missed it. Hope NT has plans to upgrade the interface to add more needed control.

What you should be able to do is have the Dynamics start and end within a key range within the scene.

Yeah that's the thing, the dynamics aren't "REALLY" supposed to take effect till the last frame, but they are obviously doing something to the IK. The IK in this example look better but the pivots or something are being displaced/offset for some reason.

I may try this with bones later instead of just object pivots to see if I get any other results.

Dynamics Cache is recorded automatically according to the project path.

jasonwestmas
03-13-2012, 07:14 PM
This is basically the same kind of scene Surrealist did but with a leg structure. So FK does work with bullet, no question about that. I just wanted to be sure the issue wasn't with the pivots. I'll have to come up with a different solution if I wanted to use IK with bullet, assuming it's possible in some way.

Surrealist.
03-13-2012, 07:25 PM
By the way good job on setting this up.

Seems to me that Bullet in LW has a ways to go. But it is a start.

There are several elements of control missing. I found out that it saves the cache in the dynamics folder of the current directory. But missing here are the usual controls you would be looking for such as being able to name and load files. Have playback controls for the files, start time and so on.

Seems by my initial look at it that there is much missing.

I mean it is simple and all but there is much missing.

Jason I think currently the solution in LightWave then is to fake it. Something along the lines of my first "from the hip" idea.

SI has all of the control parameters to set this up exactly as you want it if you decide to go that route.

jasonwestmas
03-13-2012, 07:30 PM
Yeah I'll try it in SI too but I'm still stubborn on this one and want to get it working just in case I might need it in this enviro too.

I actually found something really odd with the Right Hip box. It disappears when the dynamics become active. Maybe there's a bug going on.

Edit: I made a new hip box and that corrected the problem.

Surrealist.
03-13-2012, 09:16 PM
Cool. I am very interested in what you come up with.,

I played with the scene but could not find anything that worked.

Left me thinking the only way was to fake it. But prove me wrong man!:D

jasonwestmas
03-13-2012, 09:22 PM
Well, I had it working fine with a more stable IK chain and using the Mental Fish Motion Baker for baking the rotations to the legs. Then after I save it, the ankle box disappears when I enable dynamics. . . which of course destroyed what I was trying to do sadly.

Maybe next release. =)

I'll probably try this with bones and weight maps and see what that does. Hopefully something interesting.

jasonwestmas
03-13-2012, 10:24 PM
Fog Ticket: 44881_ehcnmorf

http://forums.newtek.com/showthread.php?p=1228616#post1228616

Surrealist.
03-13-2012, 11:20 PM
Hmmm... too bad.

Well there is a list of things I like to see with this. Probably would refine the list after becoming more familiar.

There are some other crash bugs too. Not sure what it was related to, but It crashes regularly if you try and change the dynamic type of an item with Dynamics enabled. I think there was at least one other crash but I don't remember what it was.

jasonwestmas
03-14-2012, 05:56 AM
Yeah better luck next time, thanks for the help. =)

RebelHill
03-14-2012, 06:14 AM
Im not surprised ur getting errors... The objects that become dynamic are also being controlled by IK... Try instead to create an IK setup, and parent each box to each part of that rig... then the boxes have no motion control other than dynamics and the 2 shouldnt interfere.

For quickness... jsut select each of your boxes, replace with null, bring in the box objects again and parent to each appropriate null... set dynamics on the boxes.

jasonwestmas
03-14-2012, 07:23 AM
Im not surprised ur getting errors... The objects that become dynamic are also being controlled by IK... Try instead to create an IK setup, and parent each box to each part of that rig... then the boxes have no motion control other than dynamics and the 2 shouldnt interfere.

For quickness... jsut select each of your boxes, replace with null, bring in the box objects again and parent to each appropriate null... set dynamics on the boxes.

In this last example I turned off the IK, Goals and MC for each of the right leg boxes and even baked them with Mental Fish Baker. Unless I missed something, which is possible. Also it did work until I saved the scene which seems pretty weird. If you turn off the enable IK and Enable MC you can see that the baked keyframes have completely taken over the FK animation.

I should perhaps try a shadow rig setup if your suggestion doesn't work with the dynamics.

http://forums.newtek.com/showthread.php?t=126645

jasonwestmas
03-14-2012, 10:46 AM
Well the parenting of the boxes to the joints makes the boxes not follow the rig anymore when bullet is enabled. I assume the same thing would happen with a nulls rig.

jasonwestmas
03-14-2012, 11:39 AM
I don't suppose there is a way to do some kind of dynamic parenting setup is there? Found some videos. Might be an answer there.

RebelHill
03-14-2012, 11:45 AM
same as item?

jasonwestmas
03-14-2012, 11:50 AM
same as item?

yeah, I know you can envelope that. I'll try it later.

jasonwestmas
03-14-2012, 12:03 PM
Newtek is calling the previous IK box setup a current limitation with bullet. Except I saw it work, but then broke when I saved the scene. Could have something to do with how the cache is being saved out then.

"Current limitation of Bullet implementation

Is one of the main things on for next revision."

Edit: It's more like I need bullet to be enveloped some how, not the rig/parenting itself. That was Surrealists original point I think. =)

Surrealist.
03-14-2012, 02:28 PM
Yeah, I think that would be more elegant within the current limitations. Seems to me a way to do that would be a lot easier to implement than making it work with constraints. But what do I know?

jasonwestmas
03-14-2012, 02:31 PM
I know that it takes me a while to get used to rigging in LW again. So I like your idea best so far. ;)

Surrealist.
03-14-2012, 03:14 PM
Oh right. Funny, I was talking about development of Bullet implementation. But, yeah, a rig/object swap or something like that would be more flexible rigging-wise. Given there is no way to actually start and stop the dynamics. (that actually works in this case that is)

So what I meant was it seems that adding this feature to Bullet would have been easier, or would be easier than trying to implement the use of constraints. I am thinking like a point upgrade kind of thing or even a service pack if Newtek is listening.

Just a simple frame range control of the dynamic effect. Or playback feature of cache, or both. But I have no idea how hard either thing would be to do. But it is a feature that should be there in any case regardless.

This would allow the construction of more complex scenes without having a lot of complex features implemented yet.