Chapter 18: Directed Scanning
Directed scanning lets users steer focus with directional switches.
It works best when users have reliable control in 2+ directions and can interpret spatial movement. It can reduce waiting time, but increases cognitive load.
Switch configurations
- Full directional (4+ switches)
- Reduced directional (right + down with wrap)
- Rotating arrow selection
Reduced Switch Mode
With only two switches, systems often use right + down and wrap at edges to reach every item. It’s slower than full directional, but still reduces waiting compared to auto-scan.
Design Notes
- Make the current focus obvious (crosshair, halo, or block highlight).
- Use consistent wrap rules (end-of-row/column behavior).
- Provide a simple “undo” path to avoid dead ends.