Intersection / Hit / In-Out-Volume Test between Objects and Particle Shapes
#1
Hi!

Is it allready possible to test if there are intersections between objects and particles shapes? Or if an object hits a particles shape? Or if a particles shape is partially or complete inside or outside of an object?

I don't want any physical behavior at this point, just a test from which particles can be send to another event.
The problem when I test just the particles instead of their shapes is, that the particle itself mostly is in the center of the shape, and so the shape crosses the object to be tested against much earlier than the particle.

If it is possible, can please someone tell me how it can be achieved?

Thanks Smile!
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#2
In many ways. Smile
Object test, surface test,, collision operators... to name a few... they all can lead to the next event where intersecting particles can be sent.
Start with Collision operator, and just change from bounce, to continue...
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#3
(02-19-2020, 11:12 AM)d4rk3lf Wrote: In many ways.  Smile
Object test, surface test,, collision operators... to name a few... they all can lead to the next event where intersecting particles can be sent.
Start with Collision operator, and just change from bounce, to continue...

Hey thanks for your reply!

But do the operators you listed test the particles shape mesh (its ture visible geometry) or just the particle (the point in the center of the shape)?

I think they do the second and that's not what I am looking for.  Or do I missunderstand something?
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#4
Sorry... after re reading your initial post again, I have better option.

If you want to test particles inside surface that is already present, then you can use surface test operator, and select "volume inside"

Is that what you have looking for?

(02-19-2020, 11:20 AM)TubeSmokeGuy Wrote: But do the operators you listed test the particles shape mesh (its ture visible geometry) or just the particle (the point in the center of the shape)?

I think this is how it works for mentioned operators:
(someoe correct me if I am wrong)

Collision operator:
It test only surface polygons, and if they collide with particles. You can check if you want to test inner side of the surface, outer, or both. You can also switch from bounce, to continue, so the don't bounce, and just go to the next event.

Surface test:
Similar to collision, but with lots of sub-options, like the mentioned volume inside/outside test 

Object test:
I think this one operates on pivot point based distance (but I m not 100% sure). So, you basically enter how much distance you want to select particles, within object pivot.
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#5
Thats all clear to me. But I want to test is if the particles shape mesh (not the particle as point) collides with or intersects or hits an object or is in/out of an object.
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#6
ohh that.. sorry again...  Big Grin

I think there could be workaround on that:
Try adding cloth bind operator, and then bellow particle switch (set to disable all binding)
The trick here, is that you don't need a cloth solver (that's why you are deactivating it right away), but cloth bind operator will add particle to each vertex of the mesh, if your mesh doesn't have enough verticies, then you can add subdivide operator before. 
I dont know if its possible to test it only on the polygon level... but on vertex.. yes...

Hope that helps.

Ok...

I just did a quick test, and that should be it.... attaching


Attached Files
.rar   ty-meshtest.rar (Size: 117.7 KB / Downloads: 302)
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#7
The problem of this solution is that the particles which you are testing are others than you want to send out.
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#8
You can give the particles a PhysX Shape, use a PhysX Switch to set them to "kinematic" (so they are part of the sim but don't collide or have PhysX dynamics applied), then use a PhysX Collider op to test their collisions (ie intersections) with whatever geo you want (make sure the PhysX Collider mode is set to Mesh if it's not a convex surface). The final step to get this working is to go into the tyFlow's PhysX settings and enable "kinematic collision pairs".
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#9
This does the job! Great!

Thank you!
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