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LukeLetellier

Issues with VDB as RBD Collision Object

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I have a series of objects that I've merged together & created a VDB to be used as a fixed collision object in an RBD sim where a bunch of objects pour down on top of it. The problem I'm having is that the bounding box of the VDB is being used as the collision object rather than the VDB itself. 

Sample scene attached, in which two separate cubes are merged into one VFB, but the falling spheres believe the bounding box is the obstacle. 

GIF of sample scene to demonstrate the issue:

giphy.gif

How might I remedy this?

 

Thanks!

Luke

VFB_RBD_Debug.hiplc

Edited by LukeLetellier

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If you want to use RBDs, you need to change the drop down on the rigid body solver from bullet to RBD. Since it is set to bullet, it is creating a convex hull across to connect each box.

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Like Ryan says, if you want to use VBDs as collision you should change the solver type to RBD. However, for a sim like this Bullet might be a good solution since it tends to be faster (but less accurate as RBD). To fix the issue you could set the geometry representation in the Bullet Data tab of your static object to Concave. Don't forget to direct the SOP Path to the collision mesh instead of the VDB.

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Thank you for your help & clarifications! 

To be honest, I wasn't even aware of the drop-down menu that distinguished between RBD & Bullet (I was also using the two terms interchangeably, due to my use of another app. Oops.)

Bullet appears to be more stable for my current sim (or at least, it doesn't require me to go through and change a lot of parameters). 

I also didn't realize that VDBs only worked with the RBD solver; I'm used to using them as obstacles for FLIP and smoke sims, so I just assumed that it'd migrate over. "Never assume..."

Learning every day!

Edited by LukeLetellier

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I'm really sorry that I want to ask you some other questions here. Because I have no time and I'm really anxious.

I find that you have successfully used  HQueue  on windows. So I hope you can help me .Sincerely thanks .

Below  are  my problems:

my hqueue client can't render . error: can't find the output file on job '2'

I have disabled the firewall.
I have changed the shared directory to be identical on both machines.
I have configured the Hqueue client and server to login under each machines user/pass
I have changed the HqueueServer path on both machines to:
hqserver.sharedNetwork.path.windows = \\RENDR2\HoudiniShared

I am getting near the point of giving up as I really don't know what else to try as I have followed the instructions provided by SideFX.

 my sever computer can see the client computer ,but only the local client computer can work well,other clients can not find the output file and failed.

can you assist me ? thanks again.

my config like this:

 

hq003.JPG

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Sorry that you're having issues! I notice that you're using an early version of H14, so I'm not sure if this will line up 1 to 1 with what I have. 

In your hq_Render node, see where there's the option that currently says "Render Current Hip File"? Change it to "Render Target HIP File", and then type in the direct path to the file, similar to how you typed in the direct path in the "Target HFS" Field: "H:/MyProject/Houdini/myHoudiniHipFile.hip"  <--- or whatever it'd be. On this particular field, be sure to use the full path, *not* $HIP. But be sure that every other external file reference node in your scene (Alembic, ROPs, Read/Write nodes, etc) are all using $HIP paths. 

Since you're still on H14, I'm guessing that you're on the full version of Houdini rather than Indie? If you are using Indie, be sure to go into the "Mantra Options" tab of the Hqueue render node, and uncheck the "Generate IFDs" box. 

With any luck that'll work!

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Thank you very much for your timely reply!I have tried this method before,but it seems that it doesn’t work. The permission problems sometimes are complicate. I was wondering if there were any other ways? Thanks in advance. These are my errors.

0~ZO5R7%V)7V[4_(19WFGNO.png

B(YW90GA~WIK$0DCFZ%O%L1.png

Edited by mmdxs

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Thanks again for your help!  I will take your advice and have a try.May everything goes well.

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