Say with size 1m × 2m × 4m.

What is the shortest path from A to B.

Say from point A at h = 10cm of midpoint of the shortest edge

and B at opposite side.

Solution

And now h = 20cm ?
Solution

An what if h = 30cm ?
Solution

And even more, for the pros :

A room 1m wide × 1.20m height × 1.24 length