I've got a big and slow DOP simulation with a lot of objects breaking up. Now the way I was taught was to use the ROP OUTPUT node to output .bgeo files from the simulated geometry (at object level ) and reimport into the same object once I'm happy for the final output and disconnect the simulation. Easy enough.

However, now that I've got 10 separate objects all being output to .bgeo. I've got a an issue. The ROP OUTPUT node doesn't automatically output on playback like the FILE node can and has to be “rendered” out manually. I'm assuming theres a different/better way as I can't believe I'd really want to manually re-simulate 10 times for each output node and object.

What's a good workflow?

Thanks!

whats happens when you chain the rops?

About Automatically export your geometry on playback ,you have different solution ,for example you can use Python script to press Render button in the ROP Output driver !

you can use Script SOP for executing this Python script on every frame to press Render Button or you can create an optional Digital Asset and put your ROP nodes in it ,then put your Python script in this Digital Asset (e.g you can use Python Module).

I can't remember this Script right now ,But you can find it in the Houdini Forums !

But If you just wanna resimulate your dynamic objects on every frame and export them to files on the Disk automatically ,one of the simplest way is to use Explicit Cache instead of ROP Output driver !

Just turn on Explicit cache option on the AutoDopNetwork !

One of the great feature of the Explicit cache is you can continue your simulation after last simulated frame every time that you like.

But about ROP Output Driver ,If you wanna continue your simulation after specify frame for example frame 150 ,you have to resimualte your Dynamic object at the first frame !!! :idea:

Sorry I don have Houdini right now for example files :cry:

Just started using explicit cache after reading this.

Slightly confused about one thing. How come the .sim files appear before it steps and displays in the scene view? The .sim file frame number seems to be accelerating away too.

What is going on?

Thanks

Joker386
But If you just wanna resimulate your dynamic objects on every frame and export them to files on the Disk automatically ,one of the simplest way is to use Explicit Cache instead of ROP Output driver !
Just turn on Explicit cache option on the AutoDopNetwork !
One of the great feature of the Explicit cache is you can continue your simulation after last simulated frame every time that you like.

Only problem with Explicit Cache is it's slower for larger .sim files.

Just noticed its $SF substep frame data. Thats the answer to my question.

Yes , you right.
Caching simulation on both Hard Disk or event Ram is longer than play simulation without cache , You can see if you Turn Off “Cache Simulation” option on the AutoDopNetwork ,Your dynamic play very quickly !

But there is no way , If you are sure about your simulation result , you can render your project without caching , But if you take a problem on certain frame or your system shutting down immediately , you should resimulate your project from first frame !

About playback problem ($F or $SF) , If you use Explicit cache , So you should use $SF , But if you use simple File SOP for reading bgeo files , So you should use $F :wink: