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Netvudu
03-14-2012, 05:00 PM
Itīs no mystery that with the new bullet dynamics coupled with the Fracture tool, no structure is safe anymore inside our computers :D Now, itīs only logical this is going to make a killer combination teamed with Turbulence.

I am lucky enough to own both products at work, but I canīt find a really good way of making bullet work along with Turbulence.
Of course, I can add manual emitters here and there and get good looking scenes, but we should strive for a way to somehow use bullet fractured pieces as Turbulence emitters.
So far at work, weīve come with particle based solutions (particles coming from parts of the fracturing model) which are just so so IMHO.

Any ideas?

EDIT: Of course, the problem Iīm talking about happens only when parts of the model blow up (which is quite common, by the way). Otherwise it would be easy to make the whole object a Turbulence emitter.

Netvudu
03-15-2012, 09:13 PM
well, Iīm gonna guess no replies means nobody has an idea on how to do this...yet

back to the drawing board :p

Netvudu
03-20-2012, 11:36 AM
Exactly, all these methods are manageable as long as you donīt have 100s (or 1000s) of pieces flying around.
A speed parameter would indeed help a lot, but itīs not the end all of it all because you might want a lot of stopped pieces emitting depending on the situation.
The simplest thing would be to have acces to bullet fragments somehow. That would simplify everything.
Maybe an option to convert a fractured simulated bullet object into many different objects, might also help a lot.

VonBon
03-20-2012, 05:48 PM
I don't have Turbulence but if it works with geometry then shouldn't you
Be able to use a "layered" fractured object?

Lol now I read your post Oliver. Mybad

Gumby22don
03-20-2012, 08:46 PM
I'd like to simply simulate, and then paint (a weight map for example) where I want dust/smoke/etc. to appear. To define when, it should probably offer a fadeout factor that could be set for individual brushstrokes. You're correct, right now - as with most of animation/simulation/dynamics in LW - it's manual work until boredom. :)

Instead of a painted weight map, what about using multiply by a distance-to-nearest-particle gradient on a simple particle system that over time intersects with the broken object? (Less than 30 particles shouldn't be all that slow - I think?)

Don
have a great day

Netvudu
03-21-2012, 05:52 AM
Well, in Houdini fragments get automagically sorted into groups. So you just make those groups geometry smoke/pyro sources...

...and they say Houdini is tough *shrugh*...

this is why I want bullet to give us some more info. So that we can play. The more "destruction", the more information we will need not to babysit every step of the way.

Thomas Leitner
03-21-2012, 06:44 AM
Well, in Houdini fragments get automagically sorted into groups. So you just make those groups geometry smoke/pyro sources...

Hi,
maybe I donīt understand you right, but in TFD you also can take the fractured object and let it emit smoke/dust/pyro.


this is why I want bullet to give us some more info. So that we can play. The more "destruction", the more information we will need not to babysit every step of the way.

Of course you are right, itīs always good to have more information available.

ciao
Thomas

Thomas Leitner
03-21-2012, 07:18 AM
It's about controlling where and when to emit in TFD. Simply defining all the bullet simulated geometry to emit is simply to much to call it "controllable". Not a good idea to design something a little more complex. :)
Hi Oliver,
you can control where TFD emit with a texture map so itīs possible to choose only parts of the geometry of an fractured object.
Controlling the time (varying for different parts of the same object) will be difficult. Maybe one of the "node gurus" find a way to contol a gradient with the speed of specific vertices of an object. My knowledge of nodes is to lousy for that.

ciao
Thomas

Netvudu
03-21-2012, 07:29 AM
Hi Thomas,

Yes, you can control where to emit with a texture map, but letīs take a look at a typical destruction example and maybe you will understand my problems:

- We create a wall with 100s of fragments, letīs say 500, something that bullet can perfectly simulate. In fact most production examples will need more than this.

- Now a collider comes and pushes away part of the wall. Some fragments fly away right away. Some others are untouched. A few, because of glue, remain for a few frames and then start falling.


- Now, how do you exactly create a texture map to account for all this? Itīs quite a lot of work, because, not only you need an animated texture map, or several map layers, but also you need to check ONE-BY-ONE the positions of those 500s fragments in your map to see which ones are going to get "white" and emit!!


It is seriously a lot of work, and the more fragments, the slower the process. Itīs better to use a workaround with weight maps and transformed objects from different positions in the simulation, as someone suggested in Turbulenceīs message board, but still...itīs a workaround. :grumpy:

The fact that not many people understand this problem beforehand simply tells me that very few are creating production level destructions with the new tools yet.
Letīs anticipate the problem beforehand and try to find good workflows, I say.

Thomas Leitner
03-21-2012, 08:28 AM
Hi Thomas,

Yes, you can control where to emit with a texture map, but letīs take a look at a typical destruction example and maybe you will understand my problems:

please donīt pretend that I donīt understand your questions:


....Of course, I can add manual emitters here and there and get good looking scenes, but we should strive for a way to somehow use bullet fractured pieces as Turbulence emitters.
So far at work, weīve come with particle based solutions (particles coming from parts of the fracturing model) which are just so so IMHO.

Any ideas?

EDIT: Of course, the problem Iīm talking about happens only when parts of the model blow up (which is quite common, by the way). Otherwise it would be easy to make the whole object a Turbulence emitter.

Itīs possible.


....I'd like to simply simulate, and then paint (a weight map for example) where I want dust/smoke/etc. to appear.

Itīs possible.


....So you just make those groups geometry smoke/pyro sources...

You can do it with TFD too.


....Of course you are right, itīs always good to have more information available.

...


....Controlling the time (varying for different parts of the same object) will be difficult. Maybe one of the "node gurus" find a way to contol a gradient with the speed of specific vertices of an object. My knowledge of nodes is to lousy for that.

...


....Letīs anticipate the problem beforehand and try to find good workflows, I say.

that was my attempt.

ciao
Thomas

Netvudu
03-21-2012, 09:06 AM
uh? whatīs with the attitude?

I do know youīre trying to help. So am I, and the rest of us posting here. I was pointing that given that your solution is doable but pretty slow and cumbersome to the point of being unuseable for big scenes the example would illustrate why I think that way.

"Possible" doesnīt mean good. Itīs humanly possible to create a photorealistic image with Windows Paint, but that doesnīt mean itīs the best workflow.


You quoted a lot of stuff, but not


"- Now, how do you exactly create a texture map to account for all this? Itīs quite a lot of work, because, not only you need an animated texture map, or several map layers, but also you need to check ONE-BY-ONE the positions of those 500s fragments in your map to see which ones are going to get "white" and emit"

which is where I explain why your proposed solution wonīt be good enough for most production shots.


Maybe you should try to relax. Weīre all on the same side AFAIK.

GregMalick
03-21-2012, 10:33 AM
I don't own Turbulence (too expensive for me)..

But whenever I hear the word tedious, I think of Scripting.
Is there some way that a Python script could check the size (bounding box would be sufficient) and motion of all those pieces at each frame and change the points weight value accordingly?

This thought was based on some assumptions:
1. It seems that the small pieces are the ones that should emit smoke.
2. When pieces stop moving, emitting should cease (or diminish).
3. Turbulence will re-evaluate the weights at every frame,
4. A Python script can evaluate and set the weights before Turbulence.

A script like that would not be exceptionally fast - but it would be certainly much faster than a person doing it by hand.



And please forgive any ramblings here due to my not understanding Turbulence...