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tielax11

RBD material constrained to animated geo

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For some reason, I am having a difficult time constraining RBD objects to animated geo. I have done this in the past inside dops, but I am trying to do it in the new RBD workflow.
I am fracturing a box and then successfully creating constraints to static ground geometry. I am then replacing the static ground geometry after creating the constraints with the animated one, and using the rbdconfigure to make the animated ground non-active, animated, and deforming while keeping the fractured box with the default settings. My animated ground is moving as expected in the sim, but it doesn't look like the constraints are moving the box with the ground's animation. Is there something I am missing?

I have attached a simple scene explaining what I am referring to.
Thanks in advance for the help.

rbdHelp_v001.hiplcrbdHelp_v001.hiplc

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I don't think, it'll work with an animated ground like that, when the ground moves the constraints will grow longer or shorter in the sop level to make sure they attach both the geo plus if you pass the ground in dops as "animated" it won't be simmed it'll follow it's animation and since the constraints are also growing and shrinking in sops it will do nothing. Also I don't think bullet solver updates constraint animation but I might be wrong. What you can do is try moving the ground like that with initial velocity inside dops or please tell the specific effect you want and I will give it a try and let you know the solution.

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Hmm, it should be able to work. I Here is a different example with a manual rbd dop setup, and the animation moves the constraints in the setup. The animated object has active=0 and animated=1 like in my help file. This is because the Initial Object Type is set to Create Animated Static Objects, though you would think with in the new workflow the object would get changed when with the attributes. 

constraint_anim_to_dops_fix.hip

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@tielax11 cool, I saw your file and I have made a version for you in the same file using the latest bullet solver node on sop, please check it out :) The secret is you can't animate the constraint geo in sops you have to put the animated geo separately in dops that isn't constrained. 

constraint_anim_to_dops_fix.hipnc

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Thank you for the help, however in your scene file I would be trying to constrain the box to the moving ground, in your scene you are just constraining the box to itself.

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@tielax11 The box is constrainted to the moving ground only, that's why it is moving and breaking, as I said you can't animate the constraints in sop else it won't work that's why I did the moving ground separately from the constrained ground, here's the same file with less complexity to show you that the box is moving because of the ground. 

constraint_anim_to_dops_fix_2.hipnc

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