#include <Leap.h>

Inheritance diagram for Leap::CircleGesture:

Detailed Description

The CircleGesture classes represents a circular finger movement.

A circle movement is recognized when the tip of a finger draws a circle within the Leap field of view.

Important: To use circle gestures in your application, you must enable recognition of the circle gesture. You can enable recognition with:

Circle gestures are continuous. The CircleGesture objects for the gesture have three possible states:

State::STATE_START – The circle gesture has just started. The movement has progressed far enough for the recognizer to classify it as a circle.
State::STATE_UPDATE – The circle gesture is continuing.
State::STATE_STOP – The circle gesture is finished.

You can set the minimum radius and minimum arc length required for a movement to be recognized as a circle using the config attribute of a connected Controller object. Use the following keys to configure circle recognition:

Key string	Value type	Default value	Units
Gesture.Circle.MinRadius	float	5.0	mm
Gesture.Circle.MinArc	float	1.5*pi	radians

The following example demonstrates how to set the circle configuration parameters:

Public Member Functions
LEAP_EXPORT	CircleGesture ()

LEAP_EXPORT	CircleGesture (const Gesture &rhs)

LEAP_EXPORT Vector	center () const

LEAP_EXPORT Vector	normal () const

LEAP_EXPORT float	progress () const

LEAP_EXPORT float	radius () const

LEAP_EXPORT Pointable	pointable () const

Public Member Functions inherited from Leap::Gesture
	Gesture (GestureImplementation *)

LEAP_EXPORT	Gesture ()

LEAP_EXPORT	Gesture (const Gesture &rhs)

LEAP_EXPORT Type	type () const

LEAP_EXPORT State	state () const

LEAP_EXPORT int32_t	id () const

LEAP_EXPORT int64_t	duration () const

LEAP_EXPORT float	durationSeconds () const

LEAP_EXPORT Frame	frame () const

LEAP_EXPORT HandList	hands () const

LEAP_EXPORT PointableList	pointables () const

LEAP_EXPORT bool	isValid () const

LEAP_EXPORT bool	operator== (const Gesture &rhs) const

LEAP_EXPORT bool	operator!= (const Gesture &rhs) const

LEAP_EXPORT std::string	toString () const

Static Public Member Functions
static Type	classType ()

Static Public Member Functions inherited from Leap::Gesture
static LEAP_EXPORT const Gesture &	invalid ()

Additional Inherited Members
Protected Attributes inherited from Leap::Interface
class SharedObject *	m_object

Protected Member Functions inherited from Leap::Interface
LEAP_EXPORT	Interface (void *owner)

LEAP_EXPORT	Interface (Implementation reference, void owner)

LEAP_EXPORT	Interface (const Interface &rhs)

LEAP_EXPORT Interface &	operator= (const Interface &rhs)

virtual LEAP_EXPORT	~Interface ()

template<typename T >
T *	get () const

Constructor details

◆ CircleGesture() [1/2]

LEAP_EXPORT Leap::CircleGesture::CircleGesture ( )

Constructs a new CircleGesture object.

An uninitialized CircleGesture object is considered invalid. Get valid instances of the CircleGesture class from a Frame object.

◆ CircleGesture() [2/2]

LEAP_EXPORT Leap::CircleGesture::CircleGesture ( const Gesture & rhs )

Constructs a CircleGesture object from an instance of the Gesture class.

Parameters

rhs	The Gesture instance to specialize. This Gesture instance must be a CircleGesture object.

Function details

◆ center()

LEAP_EXPORT Vector Leap::CircleGesture::center ( ) const

The center point of the circle within the Leap frame of reference.

Returns: Vector The center of the circle in mm from the Leap origin.

◆ classType()

static Type Leap::CircleGesture::classType ( )

inlinestatic

The circle gesture type.

Returns: Type The type value designating a circle gesture.

◆ normal()

LEAP_EXPORT Vector Leap::CircleGesture::normal ( ) const

Returns the normal vector for the circle being traced.

If you draw the circle clockwise, the normal vector points in the same general direction as the pointable object drawing the circle. If you draw the circle counterclockwise, the normal points back toward the pointable. If the angle between the normal and the pointable object drawing the circle is less than 90 degrees, then the circle is clockwise.

std::string clockwiseness; if (circle.pointable().direction().angleTo(circle.normal()) <= PI/4) { clockwiseness = "clockwise"; } else { clockwiseness = "counterclockwise"; }

Returns: Vector the normal vector for the circle being traced

◆ pointable()

LEAP_EXPORT Pointable Leap::CircleGesture::pointable ( ) const

The finger performing the circle gesture.

Returns: Pointable A Pointable object representing the circling finger.

◆ progress()

LEAP_EXPORT float Leap::CircleGesture::progress ( ) const

The number of times the finger tip has traversed the circle.

Progress is reported as a positive number of the number. For example, a progress value of .5 indicates that the finger has gone halfway around, while a value of 3 indicates that the finger has gone around the the circle three times.

Progress starts where the circle gesture began. Since it the circle must be partially formed before the Leap can recognize it, progress will be greater than zero when a circle gesture first appears in the frame.

Returns: float A positive number indicating the gesture progress.

◆ radius()

LEAP_EXPORT float Leap::CircleGesture::radius ( ) const

The radius of the circle.

Returns: The circle radius in mm.