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Hey Guys I have an issue here with volumes and attributes in general in fact.

So in my scene if you take a look at it, I have a vdbfromparticlefluid node that I want to change the voxel scale value based on a colored ramp that runs down the particles and colors the points from black to white. I want to force the voxelscale parameter to be pretty much like .5 when high in the air and .2 when lower in the air. I don't know enough about attributes yet to achieve this, but I want to achieve it using color from the particles. It seems almost impossible to change original parameters stored in geometry (that are essentially locked ) based on new attributes.


Of course, this being a volume, I have lost all point data information so I can't use color or anything based on points


To explain this better: How would I say take a sphere's radius in x and force the radius in x to be an newly named attribute so that when i change the new attribute, the radius changes in the original sphere based on that attribute?  So basically like channel referencing, only it will be channel referencing on an attribute that was created after the fact.  


So this is more of a "how do I change original geometry parameters based on new attributes that I created after the fact" question. I tried everything under the sun to get this to work. Channel referencing,  Volume Vops, (Don't know those yet). Attrib transfer, Solvers in Sop level, Volume from attribute, all kinds of things...


Can anyone help me? I need this for a project and I'm on a tight deadline so any help at all will be super highly appreciative. Thank you! 


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Sorry, no time to check hip files but why can't you just create attribute named "pscale" (particle scale)on your points and set that to whatever you want (ie. based on ramp, values of of other attributes like Cd (color), etc.). The VDB From Particle Fluid will automatically take the pscale attribute into account.

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Thank you for your response! Very thankful! I tried that and it works perfectly except it isn't quite the look I am desiring. Very useful trick though. The reason I am wanting this is so I can get less defined liquid at the top and more defined towards the bottom. I'm trying to create a paint effect and it looks weird to have high res throughout the whole sim, it would look cooler to look more like a stream at the top and then have a splatter look at the bottom. Thank you though for your time! Houdini is still pretty new to me but I'm trying my best to learn it quickly.

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