RBDPointObject and Flip Solver help.

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Greetings fellow Houdini users. This is my first post in here, and I'm hoping some one with far greater knowledge of the mysterious dark arts can help me!

I'm trying to birth new RBD objects into a DOP net, using a SOP point cloud that deletes randomly over time. It's fed into RBDPointObject node.

When I combine this with a flip simulation in the same dopnet it goes wonky. To me it looks like the RBD are not seeing the flip sim, but the flipsim seems to see some of velocities of the objects, even though the merge downstream is set to ‘mutual’, and flip feedback scale is active.

Is there an issue with the collision relationship or a naming issue when the new RBD are created?

The same setup works perfectly when I just birth a few RBD objects on frame one.

Hopefully someone can help point out where I'm going wrong, as I'm stumped!. I've attached a file with a working version and the broken pointobject version. Oh and I'm using build 16.0.633.

Someone put me out of my misery!

Update:

At frame 21-22, the first RBD object reaches the FLIP particles, then disappears. If i check the geometry spreadsheet it says the RBD object has a world position of 1668.48, 14438.8, 504.771. So I'm guessing it's flying off into outer space!
Edited by Woody79 - Aug. 3, 2017 17:51:44

Attachments:
FLIP_RBD_IssueA.hiplc (2.0 MB)

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Hi Tim,

I moved some things around to get this working, it seems to be ok now.

Hopefully enough to get you going!

Best,
Cris

Attachments:
FLIP_RBD_Issue_solved.hiplc (2.0 MB)

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Hi Cris, really appreciate you taking a look! Interesting way to get around the RBDPointObject, Houdini gives so many options it's difficult to know which is the correct way to do anything!

Still looks like the Cubes disappear into infinity on collision. I wonder if your using a different build of Houdini to me? I'm using 16.0.633.

Cheers

Tim
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Woody79
Still looks like the Cubes disappear into infinity on collision. I wonder if your using a different build of Houdini to me? I'm using 16.0.633.

Tim

I believe your cubes are spawning overlapped, which results in a crazy velocity.
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Hey Khye, yeh there are a few overlapping ones. But when I drop them onto a ground plane rather than into the Flip they bounce around fine. The overlapping ones are a bit weird of course, and probably don't help at all.

Still stumped…I'll try building the setup again and see if it changes!
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