I always wanted to do this, a 3D drone survey.
I took photographs from my drone in various grid patterns. These photographs were then processed using OpenDroneMap. The process took a lot of computing power, with some taking 48 hours on a 24-core processor.
Measurements can be taken for heights, widths, distances and volume accurate to around an inch.
You can view it online here:
Use your mouse to spin it around.