type Button int32

const (
	ButtonNone   Button = +0
	ButtonLeft   Button = +1
	ButtonMiddle Button = +2
	ButtonRight  Button = +3

	ButtonWheelUp    Button = -1
	ButtonWheelDown  Button = -2
	ButtonWheelLeft  Button = -3
	ButtonWheelRight Button = -4
)

type Direction uint8

const (
	DirNone    Direction = 0
	DirPress   Direction = 1
	DirRelease Direction = 2
	// DirStep is a simultaneous press and release, such as a single step of a
	// mouse wheel.
	//
	// Its value equals DirPress | DirRelease.
	DirStep Direction = 3
)

type Event struct {
	// X and Y are the mouse location, in pixels.
	X, Y float32

	// Button is the mouse button being pressed or released. Its value may be
	// zero, for a mouse move or drag without any button change.
	Button Button

	// Modifiers is a bitmask representing a set of modifier keys:
	// key.ModShift, key.ModAlt, etc.
	Modifiers key.Modifiers

	// Direction is the direction of the mouse event: DirPress, DirRelease,
	// or DirNone (for mouse moves or drags).
	Direction Direction
}