OpenVDB: Houdini to Blender export

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Hello,

Blender 2.77 has OpenVDB caching for smoke and fire. Reading Blenders VDB works straightforwardly in houdini and displays nicely in Viewport. Other way around though will result in Blender crashing.

By comparing Spreadsheets and node information, the difference in data storing becomes evident. I figure a good place to start is to try to replicate variables that Blender uses.

First problem that I face is velocity being split into 3 components (vel.x , vel.y, vel.z ) and stored as floats while in Blender you have a velocity “group” stored as vec3. Is it possible to convert these 3 groups(vel.*) into 1(velocity, vec3)? e.g in ConvertVDB node would be nice to have Group: @name=density @name=heat @name=`velocity=vector(vel.x,vel.y,vel.z)` if that makes any sense.

All in all this forum is filled with bright minds. If anyone is up to the challenge, they can grab 2.77 Blender build and see if they can figure it out.

Any information, help is highly appreciated.

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Try a vdb vector merge, that'll collapse any split x/y/z scalar field into a vector.
http://www.tokeru.com/cgwiki [www.tokeru.com]
https://www.patreon.com/mattestela [www.patreon.com]
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how does realflow export the velocity values?

it would make sense that software that can create vdb's use the same naming and file type for reducing interportability conflicts!

the openvdb team should defines some base naming(example vel, density, heat, fuel…… ) and filetype(float,int, vec) to each name definition.
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Any news on this?
I've gotten in touch with a few guys allot smarter than me, and we are all working on a solution for getting stuff from houdini into blender.
Its based on this :
https://www.youtube.com/watch?v=XogV-b9LATc [youtube.com]
We are focusing on geometry at the moment, and we do have a working python exporter. It's just a bit slow at the moment.
One of the guys is rebuilding it in vex, so we are hoping it will be fast enough to be usable.
We would like to move on to vdb if we have success with the vex code.
If you guys know how to define vdb in houdini, so that blender understand it, maybe we can all have a happy exporter soon
G
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I know this is very old post,but if actual:
U just must delete Blender's custom field for viewport preview “Shadow”.
Edited by Ivan Malishev - 2019年7月31日 11:47:10

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