Hello,
I'm trying to create collision geometry for a riverbed terrain. I tried using the “Terrain Object” shelf tool, it works but it wastes a lot of polygons on side and bottom of collision Geo. Any suggestions for more efficient way to represent the riverbed. Also, does FLIP uses RBD or bullet for collisions? I tried methods I've used with bullet, but the FLIP fluid just goes through it.
Riverbed Terrain FLIP Collision Geo
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- uuLLFA
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- Enivob
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- uuLLFA
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Enivob
Neither, FLIP has it's own collision system. To increase your collision resolution you must increase your fluid resolution.
Go ahead and post your scene, if that is possible.
Thank for the reply. I just have the self tool “Terrain Object”. I changed “Uniform Division” from 30 to 300. Is there a tutorial or page, where I can read more about FLIP collisions. I couldn't find anything specific in the docs.
Thanks!
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- Enivob
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The Terrain object may need to be converted to a mesh before you can collide with it. Drop down a Convert node at the end.
Turn off the collision guide for the Terrain object, that will slow down processing. Also you don't need 300, just use 50-90, because main collision is going to be determined by FLIP, not RBD.
On the FLIPObject turn on the Collision Guide. Then when you sim, you will see the “True” representation of the collider in light purple.
If you have not watched the Master Class on fluid, click on the Learn menu at the top of this page and locate it amoung the many tutorials.
Turn off the collision guide for the Terrain object, that will slow down processing. Also you don't need 300, just use 50-90, because main collision is going to be determined by FLIP, not RBD.
On the FLIPObject turn on the Collision Guide. Then when you sim, you will see the “True” representation of the collider in light purple.
If you have not watched the Master Class on fluid, click on the Learn menu at the top of this page and locate it amoung the many tutorials.
Edited by Enivob - Aug. 16, 2017 08:34:22
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.
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- uuLLFA
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Hi Enivob,
Thank you for this. I did turn on collision guide, and as you mentioned, the resolution goes up as particle separation goes down. Does this mean I don't even need the terrian object and/or static solver for collision? The only thing I'm simulating is water hitting riverbed, so I don't need any other RBDs. I've attached screenshot of my current node network and FLIP Collision Guide.
Thank you for this. I did turn on collision guide, and as you mentioned, the resolution goes up as particle separation goes down. Does this mean I don't even need the terrian object and/or static solver for collision? The only thing I'm simulating is water hitting riverbed, so I don't need any other RBDs. I've attached screenshot of my current node network and FLIP Collision Guide.
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- Enivob
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You do still need the Terrain collision object. FLIP basically resamples that collision object to create it's own internal collision object. I don't know why, that is just how it works. But you can get away with a lower uniform division. Also remember to turn off the volume based collision guide when simming. If it is on, it will be recalculated every frame. On a static object, you don't need that and you can pick up a little more performance by leaving it off.
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.
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