Activate gravity if temperature is higher than 0?
5251 8 0- prapra
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New to Houdini here.
I'm melting a cube that is floating in the air as a sphere used as a temperature source passes through it, but when the simulation starts the cube falls down due to gravity. I want it to stay in the air, except for the parts that are melting. So I was thinking I would set gravity's Activate property to 1 if a particle's temperature is higher than 0, and then check if then for those particles clamp the activation to 1 so it stays affected by gravity even if it was to cool down afterwards.
This way I should have a floating cube, and the parts that melt fall as they melt.
Except I have really no idea how to go about the expression. I have looked at some tutorials on expression, but it's still rather unclear to me
Thanks
I'm melting a cube that is floating in the air as a sphere used as a temperature source passes through it, but when the simulation starts the cube falls down due to gravity. I want it to stay in the air, except for the parts that are melting. So I was thinking I would set gravity's Activate property to 1 if a particle's temperature is higher than 0, and then check if then for those particles clamp the activation to 1 so it stays affected by gravity even if it was to cool down afterwards.
This way I should have a floating cube, and the parts that melt fall as they melt.
Except I have really no idea how to go about the expression. I have looked at some tutorials on expression, but it's still rather unclear to me
Thanks
- Enivob
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The gravity force can affect a group so you may want to take that approach. Migrate particles to the gravity group based upon temperature. Sorry I don't have an exact expression or setup for you.
Check out the example files under the help card of the PopObject. There are quite a few examples that show how to manipulate popstreams (stream essentially are groups).
Check out the example files under the help card of the PopObject. There are quite a few examples that show how to manipulate popstreams (stream essentially are groups).
Using Houdini Indie 20.0
Ubuntu 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
Ubuntu 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
- prapra
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- patar
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- prapra
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Hello Patar,
I added the scene, hopefully you can open it.
I tried groups, since streams don't work with flipfluid object, but it didn't workout. I'm not able to figure out where to put the group (after the solver I assume?) nor how to write the expression properly to get the resulting group desired, etc. I tried putting @temperature >0 in the group expression, but it always returns 0 since I presume it only checks for the temperature at the start, not every frame.
I added the scene, hopefully you can open it.
I tried groups, since streams don't work with flipfluid object, but it didn't workout. I'm not able to figure out where to put the group (after the solver I assume?) nor how to write the expression properly to get the resulting group desired, etc. I tried putting @temperature >0 in the group expression, but it always returns 0 since I presume it only checks for the temperature at the start, not every frame.
Edited by prapra - Aug. 29, 2016 16:41:03
- Enivob
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Here is my attempt at trying to solve this. I used a PopWrangle to add particles to the group “hot” when the temperature is over 0.38, however, even though the group is created, the Gravity node can not detect that the group exists?
When I specify the hot group manually in the gravity node nothing moves.
Maybe someone at SideFX can look into this. I thought this was supposed to work…?
When I specify the hot group manually in the gravity node nothing moves.
Maybe someone at SideFX can look into this. I thought this was supposed to work…?
Edited by Enivob - Aug. 29, 2016 21:58:25
Using Houdini Indie 20.0
Ubuntu 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
Ubuntu 64GB Ryzen 16 core.
nVidia 3050RTX 8BG RAM.
- patar
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- Enivob
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- prapra
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