Group particles and animate whole group
#1
First off again I cannot stress enough how great tyflow is

...but since I still suck pretty bad at using it I have some questions:


Basically what I am trying to do is a spinning rotor which gets fractured into bits when it collides with another object. Since I had problems with using the original spinning rotation animation of the original mesh through an actor and some (probably too complicated setup) I chose to simplify everything. Now I have only a "Birth Objects" loading the original mesh, a "voronoi fracture " breaking it up, a "Particle Bind" for holding everything together, a "PhysicX Shape" for setting up collisions.

I wanted to use a "Spin" node to animate the rotation but I would have to sort of group everything and center the pivot first. Is there a way to do that or is my approach completely nonsense?

Thank you in advance
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#2
The way I would do it is:
- Birth object (pick up the source )
- Object Bind (pick up the source, and that will drive spinning animation), select - lock to surface
- Voronoi
- PhysX shape
- PhysX Switch - kinematic (so it preserves the animation)
- PhysX Collision (pick up any collision object that you want your particles to activate and send into event where they are not bind to object)
.... So... above PhysX Collision lead to next event where you only have...
- Physx Switch - activate
- PhysX Shape (probably not needed, because PhysX Shape automatically transfer to next evet, but you might wanna change some settings)

In your setup, there's a few things you need to be aware of... mainly is Particle Bind and PhysX shape.
They don't work together.
Keep in mind there is a 2 ways to simulate rigid dynamics: PhysX, and Particle Physics.
Both solver have their own binding operator, switch operator, and others.

Particle force is simpler, and faster then Physx Shape, but it can't work on voronoi shapes, it only works as particle (sphere) that collides with each others, then can't use any other shapes.... it's ideal for sand simulation.

Hope this helps, and clear some of your dilemma.

Cheers. Smile
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#3
(03-10-2020, 03:43 PM)Thanks very much, d4rk3lf!I tried it out d4rk3lf Wrote: Thanks very much, d4rk3lf!

Especially for clearing up the difference between the particles and physX solvers. Now I get why there are seperate "Binds" and "Breaks" and "Switches" for particle AND PhysX.


I tried to put it in, like you wrote, got a little confused with the part, where it should branch of into the new event and ended up with this...

(see attachment)

For some reason it would work without the PhysX Switches, so I turned them of.

It is pretty fine the way it is now and I tried saving the "inertia" of the rotation using "Speed". On "From Last Position (Verlet)"-setting it does quite that, but is there a better way maybe?


Anyway....thank you very much. It is a huge step forward.



The way I would do it is:
- Birth object (pick up the source )
- Object Bind (pick up the source, and that will drive spinning animation), select - lock to surface
- Voronoi
- PhysX shape
- PhysX Switch - kinematic (so it preserves the animation)
- PhysX Collision (pick up any collision object that you want your particles to activate and send into event where they are not bind to object)
.... So... above PhysX Collision lead to next event where you only have...
- Physx Switch - activate
- PhysX Shape  (probably not needed, because PhysX Shape automatically transfer to next evet, but you might wanna change some settings)

In your setup, there's a few things you need to be aware of... mainly is Particle Bind and PhysX shape.
They don't work together.
Keep in mind there is a 2 ways to simulate rigid dynamics: PhysX, and Particle Physics.
Both solver have their own binding operator, switch operator, and others.

Particle force is simpler, and faster then Physx Shape, but it can't work on voronoi shapes, it only works as particle (sphere) that collides with each others, then can't use any other shapes.... it's ideal for sand simulation.

Hope this helps, and clear some of your dilemma.

Cheers. Smile


Attached Files Thumbnail(s)
   
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#4
Ok, great.
It's hard for me to tell from screenshot what exact behavior you want, but here is my thoughts:
- Try placing Voronoi above object bind operator. That way the fractures itself should be rotated, so you might not need speed operator to inherit their motion... not sure really... just a guess.
- It's actually logical why this work without switch operators, because, in first event, object bind is forcing PhysX shape to just follow it, and in the second event there is no object bind, so PhysX can behave freely. But keep in mind those switch operators, because they will come handy in future, for some different scenes.

Cheers Smile
  Reply
#5
Thanks mate!

I will definitely keep those switches in mind. So often I struggle finding tools doing specific stuff and then recognize (mostly with kind help of others Wink  ) they were in there all along.

Cheers!
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