Making parts of soft body "kinematic"
#1
Hello everybody!
Im sure im not using the right terms for my question, pretty new to particle systems.
But i´d like to have parts of the particle objects not influenced by the simulation. Couldnt figure out how to do that so far and tuts i found didnt explain this.
How do i do that?

Best regards!
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#2
Use a Particle Switch -> deactivate.

Or if you're using PhysX, PhysX Switch -> kinematic
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#3
(03-19-2020, 08:17 AM)tyFlow Wrote: Use a Particle Switch -> deactivate.

Or if you're using PhysX, PhysX Switch -> kinematic

Hello!

Im trying that right now, but its just making the whole object completly rigid. What im looking for is to have parts of the object being rigid and manipulatable and the rest under the influence of the particle system as soft body.
For example, a waving flag which has its side edge attached to a pole.
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#4
Yes, you would use those same operators I mentioned to do that.

If you check the official example files you can find places where I show how to use them.
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#5
(03-21-2020, 12:11 AM)tyFlow Wrote: Yes, you would use those same operators I mentioned to do that.

If you check the official example files you can find places where I show how to use them.

Ok i went through the examples, but couldnt find any that would make a part of the particle object absolut rigid. The flag example file is partially rigid while bound to the cord/pole, and won´t follow it when moved around.
I was thinking of something like the cloth modifier does. It lets you select verts, that you can make rigid and attach/link to an animated object. Or the surface option with soft constrainment.
Can you tell me in which example file to look to get the same results, please?
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#6
If you add an object bind operator on event 03 (in the flag sample scene), and pick that cylinder pole, you will get the effect you want (flag following the pole movement).
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#7
(03-23-2020, 11:44 AM)d4rk3lf Wrote: If you add an object bind operator on event 03 (in the flag sample scene), and  pick that cylinder pole, you will get the effect you want  (flag following the pole movement).


That worked thank you, but i still got the problem that the edge of the flag wont attach entirely to the cord/pole. Not the whole edge is bind, but only the top and bottom of it.
Maybe this setup example isnt ideal to accomplish what i was looking for? Are there other ways, maybe a more direct one for this?
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#8
It's because object tests (with points) makes only those parts of the flag being sent to another event where they move with pole (with object bind).
Just replace object test with surface test, and pick a cylinder.
That way , parts of the flag, all along (close to the cylinder) will be transferred to next event.

I hope you understand the principle (object tests sends basically parts of the flag that are close to pivot point of the objects... surface test sends particles that are close to actual surface mesh).

If it's not clear, feel free to ask, and I will elaborate more.
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#9
(03-23-2020, 01:03 PM)d4rk3lf Wrote: It's because object tests (with points) makes only those parts of the flag being sent to another event where they move with pole (with object bind).
Just replace object test with surface test, and pick a cylinder.
That way , parts of the flag, all along (close to the cylinder) will be transferred to next event.

I hope you understand the principle (object tests sends basically parts of the flag that are close to pivot point of the objects... surface test sends particles that are close to actual surface mesh).

If it's not clear, feel free to ask, and I will elaborate more.

Yes please. I really have difficulties understanding the concept off particle systems. All i know is that you do everything with particle interaction, but i dont get how you control this.
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#10
Attached you a file of most simple flag setup I can make. 

So, here's what's going: 
EVENT 01
- Birth Object 
Obviously, we pick the plane that we want to be the flag. 
- Cloth Bind
Now this is very useful and powerful operator. It's not only that adds cloth behavior, it also create particle on each vertex of the plane, and on top of that, it creates plane that is "skinned" to those particles. So, before this modifier, we only had one particle, with this modifier, we have a particle on each vertex + mesh (cloth) that will follow those particles. 
Sometimes, you will use cloth just to get particle on each vertex (even you won't use cloth), because it's an awesome way to achieve some other stuff. 
- Force 
We use this operator to just add a little bit of gravity 
- Collision 
I use this modifier to select the ground, so cloth collides with ground. You can pick whatever you want. Even animated geometry, or deflectors. 
- Suface test (distance) 
Remember that with cloth we have now particle on each vertex? So, we place this operator, and we pick cylinder. Right now, the distance value is 10cm, so I am telling him, grab every particle that is 10cm (or closer) to the cylinder pole, and send them to next event. 

EVENT 02
So, here are these grabbed particles from previous event, and they chill out here now :Smile They still have cloth properties. 
- Particle switch - deactivate 
We tell them to disable any cloth behavior they inherited  from previous event 
- Object bind - pick cylinder 
We tell them "you see this object - cylinder", go on and stick with it... just follow it whenever it goes. 
-------------------

Additionally (I disabled this particle setup), I created you a version where cloth have self collision. 
It is achieved by adding Particle Physics operator, that basically force particles to have self collision, therefore preventing cloth to self-intersect. 
You can also add a turbosmooth modifier on Tyflow Icon, if you want too smooth cloth out. 
But for nice cloth sim, you should go with more plane segments, but I created low poly, so it's more clear what is going on. 

Hope this helps. Smile

Ups, forgot attachment


Attached Files
.rar   Simple_Flag.rar (Size: 42.5 KB / Downloads: 6)
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#11
(03-23-2020, 02:23 PM)d4rk3lf Wrote: Attached you a file of most simple flag setup I can make. 

So, here's what's going: 
EVENT 01
- Birth Object 
Obviously, we pick the plane that we want to be the flag. 
- Cloth Bind
Now this is very useful and powerful operator. It's not only that adds cloth behavior, it also create particle on each vertex of the plane, and on top of that, it creates plane that is "skinned" to those particles. So, before this modifier, we only had one particle, with this modifier, we have a particle on each vertex + mesh (cloth) that will follow those particles. 
Sometimes, you will use cloth just to get particle on each vertex (even you won't use cloth), because it's an awesome way to achieve some other stuff. 
- Force 
We use this operator to just add a little bit of gravity 
- Collision 
I use this modifier to select the ground, so cloth collides with ground. You can pick whatever you want. Even animated geometry, or deflectors. 
- Suface test (distance) 
Remember that with cloth we have now particle on each vertex? So, we place this operator, and we pick cylinder. Right now, the distance value is 10cm, so I am telling him, grab every particle that is 10cm (or closer) to the cylinder pole, and send them to next event. 

EVENT 02
So, here are these grabbed particles from previous event, and they chill out here now :Smile They still have cloth properties. 
- Particle switch - deactivate 
We tell them to disable any cloth behavior they inherited  from previous event 
- Object bind - pick cylinder 
We tell them "you see this object - cylinder", go on and stick with it... just follow it whenever it goes. 
-------------------

Additionally (I disabled this particle setup), I created you a version where cloth have self collision. 
It is achieved by adding Particle Physics operator, that basically force particles to have self collision, therefore preventing cloth to self-intersect. 
You can also add a turbosmooth modifier on Tyflow Icon, if you want too smooth cloth out. 
But for nice cloth sim, you should go with more plane segments, but I created low poly, so it's more clear what is going on. 

Hope this helps. Smile

Ups, forgot attachment

Thats great! Thank you for taking the time to do this. Will come back to you after testing around to understand it better!
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#12
Hello d4rk3lf!

Went through the save and i think i understand better now. But is there another way of disabling particles and binding them to another object? As far as i understand i have to generate a mesh that is formed like the particles i want to disable and use that to bind and move around.
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#13
Not sure what you're trying to do.... however.. yes... there's million ways how you can send particles to next event... surface test is just most logical and most used for this kind of sims, because it sends particles closest to the cylinder (pole) object
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#14
Right now this is my approach to achieve what i described earlier.
On the 1. pic is a geosphere, that i want to control through the marked verts. Binding them to another object while the rest of the geosphere is under the influence of the particle system.
2. and 3. pic i created an mesh that will be disabe particles through a surface test and send them to a bind object event.

So is this how to do it the right way? Is it the most efficient mehtod?


Attached Files Thumbnail(s)
           
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#15
Could somebody give me clarification on this, please?
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