Motion blur on volume object in Blender 2.83

Hi everyone! I’ve used Blender 2.83 to import an OpenVDB fire simulation from Phoenix FD for 3ds Max. Now I would like to add some motion blur to the volume object itself (to the flames moving and not to the camera). Is It possible in Blender, maybe using the velocity data from Phoenix simulation?

I know I haven’t answered your question sorry but I was wondering how you got your vdb sim from fd into blender. When I export it as vdb sequence and try import it I have nothing in the viewport but my outliner says I have a vdb. Even the little cloud icon is there for me to play with setting but I see nothing in the viewport in blender. Any tips?

It could be caused by different things.

1, check your volume size in Blender. It is automatically imported as a huge volume so you have to scale it down to a hundredth or even a thousandth its size to see it.

2, depending on which grid you have selected in the volume properties panel you see different things and sometimes some grids are either empty or shown as empty, so try to select another grid.

3, If you are in rendered mode in the viewport you need a proper shader, orherwise you won’t see anything.

Mmm, I can see vdbs from other software in blender but not fd. So it’s a problem on my end in my maya sim. Thing is redshift reads the exported vdb and so does octane… are you using fd with max, c4d or maya?

I do see a semi transparent box representing the vdb in blender. ive scaled it down, tried adding a material, played with settings and nothing…must be something im doing wrong or not doing. sorry ive not answered the question you started your thread with. Just hoping for a hand.

I’m using Phoenix with 3ds Max, I don’t know what could be the issue. Are you sure you checked all the grids you want to export in maya?

I did check them. Which ones are you checking out of curiosity? I could upload a small vbd here maybe and you could see if it works on your end? (Can I actually do that in this forum?)

I’m using Smoke_phx and Temperature_phx but I’ve also made many tests using Fuel_phx, velocity, color… Everything was interpreted correctly by Blender. Try to upload a zip file with let’s say ten frames of your simulation and I’ll check. By the way, in your shader, did you change “temperature” with “Temperature_phx” and “density” with “Smoke_phx”, right?

I did change temp and smoke in the blender shader. I can get a smoke render but it doesn’t look the same as the maya frame. Ive shown 2 screenshots, unfortunately I cant upload a zip with the vdb files because even one takes up too much memory for the blenderartist upload. If you could take a look that would be cool.

ps, notice the big block parts as well as the rest of the vdb not been there. Its all strange to me.

I think you definitely have to either increase the blackbody intensity value or the emission strenght. Try to set the blackbody intensity to a value from 1 (1 is usually fine) to 10. Then set it to 0 and try to increase the emission strenght. The block render thing I really think is some Blender 2.83 bug: I had the same effect with OpenVDBs imported from fumeFX… but only in Cycles! Eevee rendered it correctly. Try to switch to Eevee, just as a test.

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Volume Object Type is a new thing with lots of limitations.

In 2.83, only first milestone will be accomplished.
https://developer.blender.org/T73201
Support of Motion Blur is not mentioned, anywhere.

It is normal to encounter problems, now, when 2.83 is in alpha state.
You can give feedback to developers in this thread of Devtalk forum.
https://devtalk.blender.org/t/volume-object-feedback/12267

Think I’m gonna wait till 2.83 is ready. I did however try the octane version of blender and managed the vdb a lot better. Thanks for all your help mate :slight_smile:

You’re welcome