Ask Dave #1

[@SabaKuNoLuki]

Hey Dave, thanks for your answer, I really appreciate it!
I will surely look into soup and check it out.
The things is that Houdini indie is now 199$ a year which is not that far from the soup license price.
I wondered if the same solution you mentioned(importing and meshing the particles) can be done inside of Houdini?
Anyway, thanks again, looking forward for your next tutorials

[@Davesplaining]

Sorry for the late response Shirel,
Yes indeed Houdini is obviously a good path to go down, and exactly this would not be hard to do with Houdini.
In fact since I made this video we have also the new bifrost plugin which I'll look into using for remeshing, so far what I've played with it seems really powerful but not very well documented yet. So in the meantime best of luck with houdini ;)

[@SakshamThukral]

@@Davesplaining Hey Dave, I found a better and much simpler way to get motion blur working, actually two ways (Also messaged you on Twitter).
Note that I'm a Cinema 4D user so I'm not too sure about Maya, but I assume the process should be same for the most part.
*First way:*
First of all, ofcourse, enable Motion Blur and Deformation blur in Redshift render settings.
Now, when I import the mesh as alembic, it comes with three vertex maps applied to it, named Velocity 0, 1 and 2. They contain velocity data for each axis.
So now, you just simply apply a Redshift Object tag to the mesh, go to the motion blur tab, and then enable 'Motion Vector' (in the older versions this option was called 'use velocity data'). Now, under Motion Vector are three blanks asking for X, Y and Z data. There you just fill those 3 Vertex maps. You would need to select each vertex map first and see which one is for X, Y and Z, since they don't come in the correct order (Atleast not in C4D).
The motion blur is now working but you might not see the result right away as the result is very very subtle. So you need to change two more options in the same tab called Scale and Unit.
I found that putting the scale value to 100, and then the Unit to 'seconds' gives a nice look. But you can play with both of these options to give a more intense, or less intense motion blur.
You do the same for the Foam particles as well, but for that you don't Need to mess with Scale or Unit (but you can If you want to), neither add any vertex maps (for this one there aren't any to begin with). Just simply add the RS Object tag and enable motion vector and it'll work right out of the box. I think one reason it works right out of the box might be because Cinema 4D automatically converts alembic particles into its native particle system on import. Not sure how it would be on Maya.
This is also great because you can control the intensity of motion blur for Foam and Water separately.
I can show you some screen recordings to explain better if you need me to? Just let me know on Twitter (check DMs). I'm pretty sure this same thing can be done in Maya, there are videos about Redshift Motion vectors in Maya out there.
*The second way:*
For this you need Vray. Vray has a proxy system which supports Alembic files. So you import the mesh as a Vray proxy file, and it automatically reads the velocity data correctly, and so motion blur should work right out of the box in vray render.
Apparently you can also use other render engines such as redshift, to render vray proxy files. You just need to turn off the "preview" option. For explaination, Vray proxy files have a preview option which reduces poly-count in viewport, and only renders full mesh in final render, however if we use other render engines to render Vray proxy, they just end up rendering out the preview version only. So we need to turn off preview for this to work. However I can't confirm that because atleast in C4D, Vray proxy doesn't have the option to turn off the preview.