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How to retime a dynamically fractured RBD simulation cache?

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I've found a few threads on this topic, but I haven't seen any concrete solutions or explanations that I can understand.  I've followed the DT course on how to control your fractures to start, but now I'm getting pretty stuck with what I'm trying to accomplish (explained below). I still have a lot to learn about Houdini, so please let me know if my process if 



To cache out a sim of a solid object that fractures a little bit when in the air, then shatters even more when it impacts the ground.  I'd then like to take this cached out sim and retime it.


My Process:

- Make a base object called geo_orig and fracture it with a voronoi fracture sop

- Make the geo_orig a packed "RBD fractured object"

- Use "glue adjacent" on geo_orig so I can control where the in-air shattering occurs by deleting unwanted constraints. 

- Then I go into the RBD packed object and hit "make breakable" and cache out the sim with a ROP output driver.

- I make a new geometry called geo_read_sim and drop a file node within to read the cached sim

- I append the time blend and time shift sops within the geo_read_sim node and that's when the problems start


The Problems:

- When I play the retimed sim, the geometry freaks out the moment a shatter happens.  I think this is due to new points being generated on impact?)

- Shattering related, retime unrelated: I can see shattered geometry coming out of unshattered geometry.  Like the original geometry stays behind while a duplicate geometry shatters off and penetrates through the old.  Any thoughts on why this might be occuring?



I've looked at the hip on here, but this deals with retiming a simulation, not a cached one.



This one deals mostly with volume retiming. 



This is the best one.  It says on the 1st post of the 2nd page that changing the rbd solver from bullet to rbd and messing with the FPS works... but every time i turn the rbd solver on, I lose the fracturing on impact and glue constraint work.




Any help or pointers would really be appreciated.



Edited by borbs727

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