01
Live vector field
Use a wheel or trackpad in any direction. The marker follows the input while the event values update in real time.
North
East
South
West
Scroll anywhere in this field
Primary delta
0
Direction
Idle
Normalized X
0
Normalized Y
0
Delta factor
0 px
Reported distance
0 px
Pointer offset
0, 0
02
Horizontal scrub rail
Vertical wheel movement becomes precise horizontal travel. Native page scrolling pauses while the cursor is over the rail.
Position 0 px
Last input 0 px
03
Propagation chamber
Switch between a bubbling event and an isolated child event, then scroll inside either surface to compare the counters.
Child surface
Scroll inside this circle