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DrStrik9
11-09-2015, 04:49 PM
Maybe my brain is getting too old, or I had a dream, or possibly semi-recalled an old fuzzy memory ...

Wasn't there a way to edit Bullet sims, via individually-numbered pieces or objects, or individual objects? Or am I remembering a different pre-Bullet earlier "FX" thing?

Somebody please wake me up ... :+)

cagey5
11-09-2015, 05:47 PM
That was certainly doable in the native lightwave dynamic simulations. Can't recall it in bullet but happy to be proved wrong.

prometheus
11-09-2015, 06:06 PM
Thinking of edit fx?
would have to fx scan the simulation with old clothfx or softfx.

Soft fx add null make path, or move the selected object etc...you need to set operator map to none.
or go with clothFx scan the motion to mdd, and use edit fx to move around.

so thereīs some difference, donīt try to calculate clothfx, use the file tab and scan motion to get access to editfx tools in cloth fx.
with soft fx you need to calculate or load an already existing mdd.

You could probably use dp kit and some node stuff to handle it too, but I havenīt tried.

DrStrik9
11-09-2015, 06:19 PM
Yeah, you're right. Dang.

Wouldn't it be cool if Bullet allowed individual object editing after initial solution in a similar way?

The whole reason I thought of this is because in current Bullet, I have at least one parts-body object falling through the static-body floor ...

hrgiger
11-09-2015, 06:31 PM
Well there's also Chronosculpt as well to edit simulations.

prometheus
11-09-2015, 06:40 PM
with soft fx...you can move individual parts in the animated time line, you need to set edit frame all, check the fix box and set start 0 and end of timeline use checked hard for size falloff, I think it is a bit tricky with that fall off though, you donīt want to affect surrounding pieces and itīs vertexes, but set right it can allow you to move around a bullet piece to another place than it was landed during simulation.

Hard fx edit was good to use in the old fx system, since it would just move the selected node piece not risking interference with deforming vertices...the hardfx uses bdd caching, so that will not work properly with editfx in hardfx..nor use mdd to reload in to hardfx for editing.

I hope they can implement that tech to work with bullet, I am actually sure they can..but currently that is restricted to chronosculpt, in fact...the chronosculpt editing tech is an enhancment of edit fx...I think I saw Rob mentioning that...wether or not it is a business selling argument or a technical obstacle not implementing chronosculpt editing of dynamic simulations....who knows?
fixing and editing the simulations like in chronosculpt is nice, for me personally... I dislike the idea of having to applications for it though...and I am not in desperate need of it..even though it would be nice.

Ryan Roye
11-09-2015, 06:52 PM
This video shows some 3rd party solutions


https://www.youtube.com/watch?v=5xLXxqU4v5o

DrStrik9
11-09-2015, 06:58 PM
Of course! Thank you. Would Chronosculpt allow this? I confess: my problem is that I just naturally feel sad paying additional for what was an included feature previously. I know; that was a program concept, not a promise of future development. And that was also in FX from a LONG time ago, not our current Bullet ... so I'm already getting over it. :+) Still, as much as I would like to have its use, I can't really justify $399 UDS right now. (I've seen some of the awesome stuff created using Chronosculpt.) So for now, I'll have to experiment with various slightly-changed starting points and Bullet settings for the offending objects. I also want to keep my ears open to learn about development of future controls, and hope for the best.

hrgiger
11-09-2015, 07:01 PM
Cool use of the lattice Deformer Ryan.

prometheus
11-09-2015, 07:08 PM
check this chronosculpt review by Ryan Roye...may not be the most positive, awesome if it was included in lightwave...but as an expensive separate softwave addition for correcting errors and changing dynamics..well..but it will give an idea on what you can use chronosculpt for..then thereīs a lot more of course on lightwave3d youtube pages.


https://www.youtube.com/watch?v=86Jpcln6nag

Ryan Roye
11-09-2015, 07:24 PM
Chronosculpt's main feature is performance. If you need full speed playback while editing baked, extremely-polygon-dense MDD cache data, this is what Chronosculpt was designed for and few programs, if any, come close to what it can do.

If you want value versus cost however, I'd recommend cage deformer over chronosculpt as not only can it be made to work with your objects directly in Lightwave, but it has countless other applications that are pretty much guaranteed to boost your productivity and capabilities many times over (if you're a rigger/animator anyways).

In this example, I use cage deformer to achieve ragdoll physics that you can hand-animate on top of:


https://www.youtube.com/watch?v=B5XnZl1jrlk

But you have to consider that cage deformer has limits as well... you have to be aware of how dense you make cages and how many polygons the mesh you are editing has.

prometheus
11-09-2015, 07:33 PM
Chronosculpt's main feature is performance. If you need full speed playback while editing baked, extremely-polygon-dense MDD cache data, this is what Chronosculpt was designed for and few programs, if any, come close to what it can do.

If you want value versus cost however, I'd recommend cage deformer over chronosculpt as not only can it be made to work with your objects directly in Lightwave, but it has countless other applications that are pretty much guaranteed to boost your productivity and capabilities many times over (if you're a rigger/animator anyways).

In this example, I use cage deformer to achieve ragdoll physics that you can hand-animate on top of:


https://www.youtube.com/watch?v=B5XnZl1jrlk

But you have to consider that cage deformer has limits as well... you have to be aware of how dense you make cages and how many polygons the mesh you are editing has.

Yes..thanks for reminding all that again, Itīs an area I want to look more in to later on ..bullet bone dynamics and manual keying in tranformations and editing..apart from that cage deformer ..I want to get hold of all 3rd powers tools, foremost and especially metamesh, then comes lw brush..and the rest of the tools...maybe he will have a christmas deal later on...and after that it might be interesting taking a look at your training vids..but it wonīt be until after christmas probably.

cheers.

Michael

jeric_synergy
11-09-2015, 07:39 PM
This video shows some 3rd party solutions

https://www.youtube.com/watch?v=5xLXxqU4v5o
Not to be a fanboy or anything but: is it just me, or does Ryan come up with surprising uses for all sorts of LW features, uses most people never think of??

MonroePoteet
11-09-2015, 07:49 PM
Yeah, you're right. Dang.

Wouldn't it be cool if Bullet allowed individual object editing after initial solution in a similar way?

The whole reason I thought of this is because in current Bullet, I have at least one parts-body object falling through the static-body floor ...

In another thread, I learned that the granularity of the Bullet collision detection can be improved by increased the Bullet simulation frame rate. NOT the scene frame rate, but the "Dynamics Framerate" in the Global tab of the Bullet Item Information panel (FX Tools=>Item Information). It defaults to 180, but if you crank it up to 600 or so, the collision detection may prevent the Parts object from falling through the floor. Maybe.

mTp

Greenlaw
11-09-2015, 08:01 PM
If you're using multipart objects in your Bullet sim, use BDD Scan.

http://dpont.pagesperso-orange.fr/plugins/MDD_Pointer.html

It will create a motion path for each piece in the Bullet sim that you can edit in Layout like a normal object.

One issue with Chronosculpt is that you cannot change the rotation of a selected part. I was working on a movie last year where I had to do that for one of my sims, and I wound up killing that piece and just keyframing a copy of it by hand. This is not a deal killer (CS is otherwise pretty awesome) but it's a limitation you may need to be aware of.

G.

DrStrik9
11-10-2015, 06:22 AM
In another thread, I learned that the granularity of the Bullet collision detection can be improved by increased the Bullet simulation frame rate. NOT the scene frame rate, but the "Dynamics Framerate" in the Global tab of the Bullet Item Information panel (FX Tools=>Item Information). It defaults to 180, but if you crank it up to 600 or so, the collision detection may prevent the Parts object from falling through the floor. Maybe.

mTp

Thanks, I'll give that a try. I first saw that dynamics framerate setting the other day, and have been thinking about it. Since you can greatly expand the scene framerate after sim calc (for slow-mo effects), I thought maybe the bullet sim was possibly parametric, with no framerate, but then I saw that setting.

DrStrik9
11-10-2015, 06:24 AM
If you're using multipart objects in your Bullet sim, use BDD Scan.

http://dpont.pagesperso-orange.fr/plugins/MDD_Pointer.html

It will create a motion path for each piece in the Bullet sim that you can edit in Layout like a normal object.

One issue with Chronosculpt is that you cannot change the rotation of a selected part. I was working on a movie last year where I had to do that for one of my sims, and I wound up killing that piece and just keyframing a copy of it by hand. This is not a deal killer (CS is otherwise pretty awesome) but it's a limitation you may need to be aware of.

G.

Thanks for that. It looks like another DuPont miracle. :+) I'll give it a try. I hope it still works with LW 2015.3.

DrStrik9
11-10-2015, 07:21 AM
Yes, I can confirm that upping the Dynamics Framerate (from 180 default to around 600) in this case did solve a number of "falling through the floor" problems. And the 150-frame sim only took 45 minutes to calculate! :+)

Ryan Roye
11-10-2015, 07:44 AM
Yes, I can confirm that upping the Dynamics Framerate (from 180 default to around 600) in this case did solve a number of "falling through the floor" problems. And the 150-frame sim only took 45 minutes to calculate! :+)

You should be able to get acceptable results with a bullet dynamics framerate of around 50-60... 180 is what I consider a high detail setting. I would experiment with the scale of your objects and ensure that it is optimal for what you are trying to do. In the LW manual, it says objects between 1-10m operate best with bullet. Topology of course is important too... avoid overly stretched polygons and other odd geometrical surfaces.

More advanced simulation softwares have a setting to globally adjust scale, but bullet (or lightwave's implementation of bullet) does not so you have to compensate for that.

BeeVee
11-10-2015, 09:34 AM
The whole reason I thought of this is because in current Bullet, I have at least one parts-body object falling through the static-body floor ...

Hi,

Somebody else might have mentioned this already but there are several ways to minimise Bullet interpenetrations. For your static object, (similar to FX dynamics actually) try to subdivide the floor. For the other objects, try to use the pre-made bounding Shapes - Convex pieces is a good one for parts objects and faster to calculate than the default Mesh.

B

DrStrik9
11-10-2015, 02:40 PM
Thanks, everyone, for your very helpful comments. This exercise has helped me get a bit more familiar with Bullet Dynamics, although I still have a long way to go still ... :+) I appreciate the LW community very much!

Greenlaw: thanks for recommending BDD Scan. I will try it out as soon as my long re-calc is finished.

Ryan Roye: Thanks for the reminder on object size: this one is within the recommended range. A Dynamics Framerate of 50-60 just looks way too "basic" here. 180 is better, but some mesh/convex parts are still falling through or sticking into the floor. 600 seems to be the winning ticket for this particular scene.

BeeVee: I already subdivided the floor: no real help; maybe a far tighter sub-div would be good. Changing the shape to convex pieces yielded a MUCH faster calc time (1:00 instead of 45:00!) <wow> But in this particular scene, the sim just doesn't look as cool as with all parts shapes set to mesh. I can only guess this is because so MUCH more calculation is going into the sim (?). I can live with long calc times, as long as the very subjective "cool factor" is there when the calc is complete. Sometimes you get what you pay for. :+)

jeric_synergy
11-10-2015, 07:26 PM
DrStrik9, can you quantify the lack of coolness in the convex shape simulation? Perhaps the algorithms could be tweeked-- I'd think a 4500% improvement in simulation time is worth some programming effort, even if it HALVED it to only 2250% improvement. ;)

++++
Or:
"Rough Convex"= current algorithm, 4500% improvement
"Fine Convex"= next algorithm, 2250% improvement
"Advanced Convex"= next algorithm, 1000% improvement.

Chose the one that fits your needs.

Those would be nice options, wouldn't they?

DrStrik9
11-10-2015, 11:06 PM
I probably cannot adequately QUANTIFY to anyone's satisfaction except my own, the difference between a full sim with shape:mesh as opposed to shape:convex, but I can tell you, one looked real and the other did not. I assume that this would not always be the case, so in the future, with similar scenes, I will probably always start with convex, for the much-shorter calc time, and only move on to mesh if it doesn't look real enough to me.

Art, after all, is purely subjective, and I happen to be one opinionated SOB ... :+)

Cheers