File size increase when reading/writing vdb


is it to be expected that when reading in an existing VDB cache, then writing it back out without any modifications leads to an increase in file size?
Is there some re-compression happening that leads to degradation?

Hi Frank,

We currently interpolate the vdb cache as we are transferring it to our GPU data structure. So yes there will be numerical degradation if you read/write in place.
This might be something we can address by supporting the vdb format more natively in the future.

In regards to the file size change, i assume this might be a bug where Eddy generates a slightly larger bounded area and the additional tiles cause the increase in memory. I assume you’ll see some more sparse tiles that are empty ( they should have been removed before writing ).

I’ll add a ticket for the latter.


I see, thanks for clarifying.