Implements a 2D slider UI element. Tracks user interactions and translates the slider position into normalized values.
The draggable handle of the slider.
The slider's movement bounds.
Normalized output values in the range [-1, 1].
Tracks whether the user is hovering over the slider.
Reference to the spotlight controller.
Half the width and height of the slider's bounds.
Tracks whether the handle is being dragged.
The initial scale of the slider handle.
Factor to scale the handle when it is being dragged.
