more intensive than WHAT ?
What is a non-volume filter ?
again : YOUR VOLUME MAKES NO SENSE.
even in real life, a volume is described by its limit.
The only case where it’s worth it to represent a system as an aggregate of points is when there are very complex relations between those points, for example nuclear/thermal/fluid modeling.
In most cases you don’t need to have a discrete modeling of space and instead can use continuous effects, that is the “volume” is modeled as forces applying to the interesting elements of the system. So your whole system is only represented as a very little number of items to manage (that’s why it’s hollow)