I guess this is more of a workflow issue, as I'm not quite sure if I'm going about this correctly.

First off, the details. I'm running Apprentice 10.0.249.5 on OS X 10.5.5. I've been following the PyroFX Tools Tutorial included in the help files, and have run into a bit of a problem. I first ran a low res sim of just a simple billowy smoke container, and got the overall motion looking more or less how I wanted. I baked out the low res sim to disk by going into the “pyrofields” node inside the “lowrespyro” object.

I then hit play to run the sim back to say frame 100 for example, with the low res pyrofields node set to Load from Disk, and density turned on in the visualization options for the uprespyro node inside the AutoDopNetwork. So far so good. I tweak the turbulence settings and what not for the uprespyrosolver node, and get the test renders looking how I want.

Now, I go to repeat the process of cacheing out the sim, only this time (obviously) with the pyrofields node from the uprespyro object. The problem is, once I do this, the high res sim looks totally different. It's as if it's not reading the velocity and density information from the low res solver, and is recalculating everything on its own, which kind of defeats the purpose. I noticed there is a check box for “Use Low Res Source” on the uprespyrosolver node, which is off by default. Turning it on didn't seem to make a difference.

Any suggestions as to what I'm doing wrong?

You are using Houdini 10.5.5!

10.5.5 is the OS X version. Trippul_G is using 10.0.249.5.

Trippul_G, it's hard to know what you did without seeing your hip file. Are you still able to get the renders looking how you want from the dop sim? If yes, it's best to post your hip file so we can take a look to see.

Cheers!
steven

Ah, ok then. The hip file's at work. I'll see if I can work something out myself over the weekend, and if I still am having problems, I'll post what I have when I get back to work on Tuesday. Thanks!

Ok, quick question: so I've kept things basic…just added a default sphere for emission, and added the default billowy smoke Pyro FX.

Didn't change any of the settings other than the frame range, and making the simulation box a bit bigger (10/20/10). I can get both the high res and low res to render, but it seems that if I cache them out to disk (and subsequently turn on the Load from Disk checkbox), when I hit render, nothing shows. If I uncheck Load from Disk, the smoke renders. Is this a limitation of the Apprentice version, or is there perhaps something else I'm doing wrong?

I can attach the hipnc file if it'd make it easier…?

Hi,

It didn't occur to me until now. Please check out this thread [sidefx.com] for the reason why writing out to disk on OS X is giving you problems.

I highly recommend updating to the latest build as it defaults to the Houdini file browser.

Cheers!
steven

Thanks for pointing me to that other thread, I think I've got things straightened out now. Though I still can't seem to figure out why, even after caching out both high and low res sims, Houdini still insists on re-cooking the sim if I close the file and then re-open it…? But at least I've gotten this far…baby steps, I guess…lol. :?

Hi,

I'm glad things are sorted out now. With regards to cooking, you have to be aware with what's displayed. If there's a display flag set on a SOP that's reading from the sim, Houdini will cook. Or if the DOP Network itself is display, that will cause cooking too.

All said, you can always hit the Esc key to cancel any cooking.

Cheers!
steven