Automate Caching and Rendering in One Process?

[pupps09]

Hi,

Pretty much a beginner in Houdini and was wondering if there is an efficient way to automate the following process.

step 1. write out a cache(.bgeo, etc...) using a DOP I/O or File Cache SOP.
step 2. After the files are written, automatically have the SOP switch to "Load from Disk"
step 3. render out the result in Mantra.

Was thinking a Post-Render Script which would switch the read/write inputs inside the DOP I/O or File Cache SOP would be the answer, but not exactly proficient in scripting.

Any kind of help would be appreciated. Thank you in advance.

P.S. Attached an example to clarify what I'm trying to do. 

[carlo_c]

Hey so I'm not sure if this is the *best* way of doing it, but it's what I do when I need to do something along these lines and it works for me  I've put sticky notes in the example as I think it's easier to understand in Houdini, confused myself trying to type it out here 

cache_render.hipnc

[pupps09]

Hey Carlo, thx for the hip file!

It works great...but if I were to have to cache out another node downstream, for example the flip surface cache in the example above, does that mean that I would have to break apart the existing node tree and add a file SOP(reading the output geo from import_wavetank) before the particle fluid surface node?

[carlo_c]

Yeah so where ever you want to cache you can just put a null there and a file sop after. In the case of your network above, you'd put a null after particlefluidsurface1 then you can drop a geometry node into out and use that to render your cache. You'd have a file SOP after the null reading back in the cached geo. The idea is to get all the actual geometry render nodes into the out context so you can chain them up to render together.

I'm not sure how to do it any other way, if there is a way hopefully someone will jump in but I find this way the simplest for me to understand and implement.

[pupps09]

OK, I understand the thinking behind your process and there's no doubt it works. Will def implement this until I find another solution 

Was just hoping there was a way without breaking the node tree apart, just in case I had to re-adjust the simulation. 

Thx for the help! Much appreciated.

[carlo_c]

Having slept on this, you could always wire up a switch like so. If you have multiple switches, channel reference all their inputs to a master value on a null so one toggle switches them all between cache and pass through.

 

Edited September 30, 2016 by carlo_c

[pupps09]

Thx! Havent yet tried this out, but if you're gonna do it through switches, I believe that the DOP I/O SOP is actually doing the switch internally, so maybe better to reference the internal switch and not have to add the extra File SOP?

Anyways, will give it a try later. Thx for the advice.