I'm trying to create cheerios falling into milk.
I did a test with 2 toruses falling into a flip sim.
If the toruses are separate RBD hero objects, then the sim works fine.
https://drive.google.com/open?id=1Z98WekxuaIQ89vmxReqRHTgWjxgkuPUX [drive.google.com]
However, if I try using packed RBD objects, then the sim explodes.
https://drive.google.com/open?id=13U4Su0a3iVEpLx38lEuWxpORUdciKZCP [drive.google.com]
I tried reducing the flip solver interaction scale from 1 to 0.5, but that didn't help.
Do packed rbd objects interact correctly with flip correctly in houdini 16.5?
What am I missing?
thanks
Packed RBD Objects and Flip Explodes
5653 13 1- syntheticperson
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- Enivob
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I think what you are seeing is the result of different collision types. The hero object uses Volume Based collision which creates a volume to represent the torus with a hole in the center. But the default collision type for RBD is bullet convex hull which makes a pill type shape, not a torus type shape. (i.e. the hole in the center is not detected). To fix this turn on Show Guide geometry on the RBD Packed Object and choose Concave for the geometry representation. This will give you a collision object that better represents the torus.
Using Houdini Indie 20.0
Windows 11 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
Windows 11 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
- syntheticperson
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- syntheticperson
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That fixed the problem!
Much thanks!
https://drive.google.com/open?id=18nTq-8GFyKJA9IBRB2Rswbb6aZxw0AI_ [drive.google.com]
Much thanks!
https://drive.google.com/open?id=18nTq-8GFyKJA9IBRB2Rswbb6aZxw0AI_ [drive.google.com]
- syntheticperson
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Sorry, I celebrated too soon.
The previous test turned out to be 4 hero RBD objects with the friction and bounce fixed.
The 2 packed RDB objects still explode with the concave collision geometry.
Here is a flip book:
https://drive.google.com/open?id=1qylYEp4lXltHR_e7ef3nvvARQzUwadyn [drive.google.com]
One torus gets stuck in the collision walls of the fluid container.
The other torus shoots off frame over one frame.
I reduced their bounce and friction to 0.1
What am I missing?
thanks
The previous test turned out to be 4 hero RBD objects with the friction and bounce fixed.
The 2 packed RDB objects still explode with the concave collision geometry.
Here is a flip book:
https://drive.google.com/open?id=1qylYEp4lXltHR_e7ef3nvvARQzUwadyn [drive.google.com]
One torus gets stuck in the collision walls of the fluid container.
The other torus shoots off frame over one frame.
I reduced their bounce and friction to 0.1
What am I missing?
thanks
- N-G
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- syntheticperson
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Good to know. I do want mutual relationship between the RBDs and the flip.
Does this mean that packed RBDs are really not suited for this?
When you say “unpack rigid body objects”, do you mean there is a way to convert a packed RBD object into hero RBD objects procedurally?
Or do I need to rebuild my sim so I'm using hero RBDs only?
If that is the case, how do you manage many hero RBDs?
I want to be able to have potentially 100s of hero RBDs interacting with flip.
Is there a way to do this so that I don't have to set them all up manually?
Does this mean that packed RBDs are really not suited for this?
When you say “unpack rigid body objects”, do you mean there is a way to convert a packed RBD object into hero RBD objects procedurally?
Or do I need to rebuild my sim so I'm using hero RBDs only?
If that is the case, how do you manage many hero RBDs?
I want to be able to have potentially 100s of hero RBDs interacting with flip.
Is there a way to do this so that I don't have to set them all up manually?
- N-G
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- Enivob
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- syntheticperson
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- syntheticperson
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- N-G
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- syntheticperson
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- HarmonCreative
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