vdb activate and deactivate puzzle

[anicg 12]

I attach a file where I expand and then deactivate the vdb. Question: since it is a vdb which, correct me if I'm wrong, only computes voxels where there is density information, why is it that when I use vdbactivate the number of voxels increase while there is visible no density there? does vdbactivate add a tiny vdb value just the additional voxels? And if that's the case how does the vdb deactivate know which voxels need to be deactivated, there are empty, right, but if they are empty they shouldn't be counted in the number of voxels in vdb activate.

Any idea why the number of voxels increase with vdb activate and how does vdb deactivate know which voxels to shrink?

vdb activate and deactivate.hiplc

[Benyee 5]

Quote

On 2022/6/22 at 12:34 AM, anicg said:

Any idea why the number of voxels increase with vdb activate and how does vdb deactivate know which voxels to shrink?

 

"vdb deactive" always detects voxels whose value equals background value currently and get them deactive or "removed"

the value of voxels you expanded equal background value,so qualified,

and for SDF is in the the same way

hope i helps

vdb activate and deactivate_v2_od.hiplc

 

 

Edited Friday at 01:43 PM by Benyee