A valuator is a representation of the state of an input device in
terms of a physical quantity such as length. A valuator event, of
type gii_val_event, reports a change in any of those quantities.
GENERATED EVENTS
This structure is used for the evValRelative and evValAbsolute
events.
STRUCTURE MEMBERS
A valuator may be either absolute or relative, like pointer motion
events.
To interpret the numbers, query valuator device info with the
GII_CMDCODE_GETVALINFO command code.