Exporting Pyro sim to Maya??

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So I've created a cool looking flame in Houdini and I want to take it into Maya so I cant render it within my scene so I can get all the lighting and shadows etc. However I'm having a lot of trouble getting anything to work. I've tried exporting it by Alembic and the only thing I get in Maya is the bounding of of the sim but no fire. I've looked all over Youtube and Google and cant find anything. I would really appreciate it if someone got back to me

I've attached my Houdini project so people can have a look at it too.
Edited by lapd100 - Feb. 3, 2021 17:35:52

Attachments:
FlameTesting.hip (1.1 MB)
Screenshot 2021-02-03 223334.png (51.4 KB)
Screenshot 2021-02-03 223535.png (516.9 KB)

Liam
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haven't tried it myself tho
https://youtu.be/qTxC0oLuhYs [youtu.be]
https://linktr.ee/Deviner_vfx [linktr.ee]
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Instead of Maya the more important thing is which renderer you are going to use inside Maya. Your best bet is to export the Houdini volume as a VDB. Redshift inside Maya can render vdb, I heard (never tried) that Arnold also can import vdbs so can render them. Give this one a try which is the way to do it with Redshift: https://www.youtube.com/watch?v=xnTFUiOpQ0M [www.youtube.com]

You might also want to try this one: https://www.youtube.com/watch?v=mRrMNWx0lGc [www.youtube.com]

There is nothing wrong with your Houdini scene. To convert your PyroSim to a vdb you can follow the steps below:
1- go into "pyro_import"
2- under "import_pyrofields" attach a "convert VDB". Inside write @name=density for Group, select VDB from the Convert to option.
3- after the "convert VDB" plug a file cache and export your volume as vdb by writing $HIPNAME.$OS.$F.vdb into Geometry File.

Attachments:
vdb setup.jpg (107.4 KB)

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OK thanks. I'm trying to export an IsoOffset node, connected into a filecache. Will Arnold in Maya render this? So far it's not working. Should I convert the isoOffset to VDB, or replace the isoOffset by a VDB node?
Houdini gamboler
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So I did more tests with this scene and I deleted my isoOffset node and replaced it with a "Convert VDB" node.

Check the attached pic : in the "pyro_import" node, I did a file cache from the import_pyrofields and plugged it into a volume visualisation node, in which I have a gradient. Then I plug this in a convert VDB node and in the bottom of my network, I use another filecache node in which I pout the vdb extension.

I understand the volume visualization node is for the viewport only, but is there a way to get these colors exported to the VDB files? And then how can I recover these colors in Maya?
Thanks
Gz

Attachments:
export VDB keep colors.png (496.7 KB)

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I reckon you need to remap the same colours in Maya based on "heat" field.
Or remap the heat field the same way in Houdini and export the "Cd" vector field to Maya.
https://linktr.ee/Deviner_vfx [linktr.ee]
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Thanks. Another question, how can I export the heat and Cd fields in the final filecache node?
BerkErdag said : in the "convert VDB" node, write @name=density for Group.
Should I write in : @name=density @name=heat @name=Cd ?
Houdini gamboler
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Hi, you also need to convert your fields to a single field.

I think this should help
It shows how to create a vector field from a float field and how to add colors to it and convert to vdb.

Attachments:
volume_vector_v001.hiplc (97.4 KB)

https://linktr.ee/Deviner_vfx [linktr.ee]
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Thanks a lot Deviner! As this file is more technical than my knowledge I have some questions :

So here's what I understand from your scene:
- box1 : You start by a cube
- vdbfrompolygons1 : You convert it into a density fog VDB
- copy_for_3_fields : You duplicate it so now you have 3 densities
- name_to_Cd : You convert each densities into color information
- volumewrangle_your_stuff_here: you create a colored ramps and you apply it into the Color (Cd). To distribute the color, you use the vertical size of the original box.

Now as you can guess I want to use the heat instead of the vertical size of the box. From my Pyro_Import node, I could extract only the heat using a delete node. But my first question would be: how can I know the range of the heat? Does it go from 0 to 1, like the Cd color?

Cheers
David
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