Hi,

I have a simple setup where I am emitting from a surface packed geometry, both fractured and non. The name attribute is unique for each piece and everything works fine as is.

I would like also to delete some of those based on their age or distance from camera and can be done easily, but its causing pre-fractured objects to explode in the air, without any collision or any other force applied to them. I am guessing that has to do with the point number and I am not sure how to fix this.

There is an attached file to demonstrate the problem.

Also last and least important question, is there any way to have a constrain network to be updated while new pieces are emitted?

That bug was fixed a few days ago:

Houdini 13.0.488: Fixed a bug in the Bullet solver that could cause initially overlapping objects to explode after an object was deleted from the simulation.

For your second question, you want to make sure that you don't completely rebuild the constraint network each frame, since that could introduce glue bonds between objects that are close together on the current frame but weren't initially close together. One approach would be to run a SOP Solver over the constraint network's geometry, and add in new constraints for the objects that were just added to the sim.

Thanks for your reply.

I am installing the latest production build and I hope everything will go smoothly on that side.

Regarding constrain network. So, I create a sop solver, inside the constrain network geo, which adds constrains of new objects in the existing constrain network. Or can I do it inside DOPs in the sopsolver connected to constrain_networkDOP (input: constrain solvers) which for now deletes the broken constrains?

I think it's probably easiest to do it in DOPs inside the same SOP solver that deletes the broken constraints.