Unigine::Plugins::LeapMotion::Hand Struct
| Header: | #include <UnigineLeapMotion.h> |
Hands are the main entity tracked by the Leap Motion controller. The controller maintains an inner model of the human hand and validates the data from its sensors against this model. This allows the controller to track finger positions even when a finger is not completely visible.
The Leap Motion software matches the internal model against the existing data. In some cases, the software can make an incorrect match – for example, identifying a right hand as a left hand.
This structure represents a physical hand detected by the Leap and provides access to its attributes describing the hand position, orientation, and movement. All coordinates are relative to the origin of the Leap Motion coordinate system.
The Hand structure is declared as follows:
struct Hand
{
int id;
int type;
int is_valid;
float palm_width;
Unigine::Math::vec3 palm_position;
Unigine::Math::vec3 palm_stabilized_position;
Unigine::Math::vec3 wrist_position;
Unigine::Math::vec3 palm_velocity;
Unigine::Math::vec3 palm_normal;
Unigine::Math::vec3 direction;
Unigine::Math::mat4 basis;
Arm arm;
Unigine::Map<int, Finger> fingers;
};The last two items of the struct are:
| arm | Arm of the hand. |
| fingers | List of all fingers of the hand. |
LeapMotionHand Class
Members
int getId ( ) #
Returns the id of the hand.Return value
ID of the handint getType ( ) #
Returns the type of the hand.Return value
Type of the hand:- 0 - left hand
- 1 - right hand
float getPalmWidth ( ) #
Returns the width of the palm when the hand is in a flat position, in meters.Return value
Width of the palm when the hand is in a flat position, in meters.vec3 getPalmPosition ( ) #
Returns the coordinates of the position of the palm.Return value
Coordinates of the position of the palm.vec3 getStabilizedPalmPosition ( ) #
Returns the modified palm position with some additional smoothing and stabilization applied. Smoothing and stabilization is performed in order to make this value more suitable for interaction with 2D content. The stabilized position lags behind the palm position by a variable amount, depending primarily on the speed of movement.Return value
Coordinates of the modified palm position with some additional smoothing and stabilization applied. Smoothing and stabilization is performed in order to make this value more suitable for interaction with 2D content. The stabilized position lags behind the palm position by a variable amount, depending primarily on the speed of movement.vec3 getWristPosition ( ) #
Returns the coordinates of the position of the wrist.Return value
Coordinates of the position of the wrist.vec3 getPalmVelocity ( ) #
Returns the rate of change of the palm position, in m/s.Return value
Rate of change of the palm position, in m/s.vec3 getPalmNormal ( ) #
Returns the coordinates of the normal vector to the palm. If a hand is flat, this vector will point downward, or "out" of the front surface of your palm.Return value
Coordinates of the normal vector to the palm.vec3 getDirection ( ) #
Returns the normalized direction from the palm position toward the fingers.Return value
Normalized direction from the palm position toward the fingers.mat4 getBasis ( ) #
Returns the orthonormal basis vectors for this Bone as a Matrix.
Basis vectors specify the orientation of a bone:
- X - Perpendicular to the longitudinal axis of the bone; exits the sides of the finger.
- Y (or up vector) - Perpendicular to the longitudinal axis of the bone; exits the top and bottom of the finger. More positive in the upward direction.
- Z - Aligned with the longitudinal axis of the bone. More positive toward the base of the finger.
The bases provided for the right hand use the right-hand rule; those for the left hand use the left-hand rule. Thus, the positive direction of the x-basis is to the right for the right hand and to the left for the left hand. You can change from right-hand to left-hand rule by multiplying the z basis vector by -1.
You can use the basis vectors for such purposes as measuring complex finger poses and skeletal animation.
