Applied Dynamics: Volume Source & Smoke Object

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Hello,

this is related to Stephen Knipping's Advanced Dynamics Tutorial Series. I'm not sure if his tutorials qualify as being part of the SideFX.com - if not, apologies but I'm hoping we can move it to the Technical Discussion instead.

So I'm a bit confused about the SmokeObject's Initial Data and the VolumeSource. In Applied Dynamics II he says that he doesn't need to input Density SOP Path and Temperature SOP Path in Initial Data because he will use the (Houdini 16) Source Volume to source those. So now in Houdini 17 - following his Houdini 17 update - I use a VolumeSource. Everything is great so far.

However when I was trying to cache my sim using a File SOP and a DOPImportField, it wouldn't play the cache unless I added my SOURCE (PyroSource's Null) to the Density/Temperature SOP Path. Once I did that it would play the cache I had saved.

So I'm a bit confused, I may be doing something wrong, or this might just be the case.

Thank you and again I'm sorry if I should have posted this question in the Technical Discussion.

PS: Sorry but English isn't my first language.
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ImNotJohnSmith
However when I was trying to cache my sim using a File SOP and a DOPImportField, it wouldn't play the cache unless I added my SOURCE (PyroSource's Null) to the Density/Temperature SOP Path. Once I did that it would play the cache I had saved.


This part is not really that clear. Usually there isn't the need to use the Density and Temperature SOP path you mentioned.

If you use the VolumeSource, have you selected the PyroSource's Null in “SOP path” (always inside the VolumeSource)?

If yes and you can see the simulation running correctly inside the DOP network, I guess is a problem with the DOPImportField. Maybe you aren't importing the right fields from DOP?
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Hello,

thank you for getting back to me. I'm happy to tell you that I (think I) figured it out. I was being a bit stupid actually and was mixing up the SmokeObject and the VolumeSource. I was basically using the VolumeSource to import the fields from my Source in the PyroSim, but I was asking Houdini to cache the data imported by the SmokeObject. The SmokeObject hadn't imported any data (Initial Data should have been empty right?) because the VolumeSource was doing it. So naturally there wouldn't be any cache to play. Or at least that's what I think was happening. I'm caching right now and I'm importing everything from the VolumeSource this time. I think that was what I was doing wrong, I hope I'm not wrong and this was the error on my part.

I'm eagerly awaiting the feeling of satisfaction that comes with solving such small issues.
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Yes you are right. The Initial Data should be empty if you import your fields with the VolumeSource.

For example, using DOP Import Fields to import the volumes from DOP I usually put:
In DOP Network the path for it -> /obj/dopnet_pyrosim
In Default Object the name of the SmokeObject -> smokeobject
Then you can select one of the presets in the dropdown menu -> Pyro for example

That should be enough
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hello, i am relateded to dust storm i added a dop network and added a pyro slover and smoke object and volumeobject i linked my volume with main geo and i want to add a source object to smoke object i am clicking parameter setting it is showing no preset but in tutorial it shows source object
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