Why does POLYEXTRUDE break my RBD sim?

[5DNick]

Dear ODForce,

 

I can't work out why adding a polyextrude before my RBD chain (in order to fix the dodgy looking geometry that the RBDmaterialfracture node creates) causes the simulation to not move anymore?

 

The offending node and NULL OUT I'm watching are colored red.

 

Thanks

 

5D

SPACESHIP_CRASH_010.hiplc

[sipi]

I opened your scene but I don't see the spaceship, only 548 packed alembics. Try to stash unpacked, converted geometry instead of packed alembic. Because now you only stash the alembic reference I believe.

[5DNick]

[pls ignore]

 

Edited yesterday at 05:23 PM by 5DNick
error

[5DNick]

[pls ignore]

Edited yesterday at 05:24 PM by 5DNick
error

[5DNick]

Here is my fixed .hip .......

SPACESHIP_CRASH_011.hiplc

[sipi]

First of all, opening the hip, running the sim gives this result:

Is that right?

 

Now, enabling that Polyextrude SOP drastically slows down the setup. I tried to cook the node tree, and already at the constraint creation i ran out of ram (32 GB), unfortunately i can't check the simulation with the Polyextrude ON, my machine can't take it.

All i could do is to select a small portion of the spaceship, blast the rest and run the setup with that, but in that case the sim was running. (however still got crazy)

 

I actually don't see what is your problem with the geometry with the "without polyextrude" version. Could show a picture maybe where the problem is visible? Rght now I rather worry about the simulation

 

[5DNick]

Yes that is "correct", as in what happens when you run it. It's not obviously a result I want in the end! This is just the beginning of my setup rather than anything anywhere even close to part way through!

I was more just curious as to why the polyextrude means the sim doesn't run? (as I was building a much bigger more complex setup).

Yes the level of RAM needed is excessive too, so I need to optimize anyway.

If you did get it to work you'd see the fracturing isn't very consistently sized and shaped anyway so that's another problem. I just wanted some thickness and it to look better than the problem I had. Funnily enough with the new setup that I was forced to create to fix your initial problem with my stash, that problem disappeared: must've been because of running unpacked geo into the RBD fracture.

 

[tamagochy]

I open your scene and this setup will not work normally. You need to clean up geometry separate small pieces and fracture only big ones. You change rbdfracture to treat income object as  as surface but after polyextrude it solid one. Overall better to find tutorial and start from there.