I seem to be missing an icon for horizontal dimensions.
It also seems more logical to me to have the icons in the order:
Another nice detail would be if the expandable toolbar is aligned in such a way that the current selection of the expanded bar is next to the original icon.
Other measurements I would find very useful are measurements to add the horizontal, vertical, or both (X, Y) distance from a reference position. These measurements are particularly useful for manual operations on a machine with a DRO (Digital Read Out), as is common these days.
Graphical it could look like:
- Horizontal leader for vertical measurements.
- Vertical leader for horizontal measurements.
- The angled leader with X and Y between parentheses, I.e: ( 203, 45)