Ohhh! So it makes sense why there's not such a function. I finally ended up doing my setup using that auxiliary voxel to point step. But like you, I thought it was a waste of resources. I could avoid it in the past because I could calculate the value of the voxel. This time I am translating voxels and the inverse function is not easy to calculate from the destination. It was actually faster than I thought - translating around 5 million voxels took less than a second.
And actually, I am using around 40% of the voxels in the container so this 'voxel to point' system might save some computation time. If calculate from the destination I would have to query every single voxel to see if the origin is active.
Thanks for the feedback, howiem!!