Unigine.Plugins.LeapMotion.Arm Struct
Notice
LeapMotion plugin must be loaded.
This structure represents a forearm. All coordinates are relative to the origin of the Leap Motion coordinate system.
The Arm structure is declared as follows:
Source code (C#)
public struct Arm
{
public float width;
public int is_valid;
public vec3 direction;
public vec3 elbow_position;
public vec3 wrist_position;
public vec3 center;
public mat4 basis;
};LeapMotionArm Class
Properties
float width#
Returns the width of the forearm, in meters.
vec3 elbow_position#
Returns the coordinates of the elbow position.
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
vec3 wrist_position#
Returns the coordinates of the end of the bone, closest to the finger tip (distal).
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
vec3 center#
Returns the coordinates of the center of the forearm.
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
vec3 direction#
Returns the normalized direction in which the arm is pointing (from elbow to wrist).
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
mat4 basis#
Returns the orthonormal basis vectors for the arm as a Matrix.
Basis vectors specify the orientation of the arm bone:
- X - Perpendicular to the longitudinal axis of the arm bone; exits the arm laterally through the sides of the wrist.
- Y (or up vector) - Perpendicular to the longitudinal axis of the arm bone; exits the top and bottom of the arm. Increases in the upward direction.
- Z - Aligned with the longitudinal axis of the arm bone. Increases toward the wrist.
The bases provided for the right arm use the right-hand rule; those for the left arm use the left-hand rule. Thus, the positive direction of the x-basis is to the right for the right arm and to the left for the left arm. 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.
Notice
Converting the basis vectors directly into a quaternion representation is not mathematically valid. If you use quaternions, create them from the derived rotation matrix not directly from the bases.
int is_valid#
Returns 1 if the arm contains valid tracking data; otherwise, 0.
Members
Last update:
2021-04-29
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