Double-tap state
Timestamp of the last tap.
Dragging state
Previous pointer coordinates [x, y] during drag.
Start coordinates and timestamp [x, y, time] of the drag.
Pinching state
The image being pinched (relevant for split-screen).
Initial distance between pinch points.
Was panning active before pinching started?
State for debouncing 'update' events.
Stack of event types that triggered the update.
Timeout ID for the debounced update.
Internal state variables used by the Events controller.