Unigine.Plugins.LeapMotion.Bone Struct
Notice
LeapMotion plugin must be loaded.
This structure represents a bone of a finger. All coordinates are relative to the origin of the Leap Motion coordinate system.
The Bone structure is declared as follows:
Source code (C#)
public struct Bone
{
public int type;
public float length;
public float width;
public int is_valid;
public vec3 prev_joint;
public vec3 next_joint;
public vec3 center;
public vec3 direction;
public mat4 basis;
};
LeapMotionBone Class
Enums
TYPE#
Name | Description |
---|---|
METACARPAL = 0 | Metacarpal bone. A bone connected to the wrist inside the palm. |
PROXIMAL = 1 | Proximal bone. A bone connecting to the palm. |
INTERMEDIATE = 2 | Intermediate bone. A bone between the tip and the base. |
DISTAL = 3 | Distal bone. A bone at the tip of the finger. |
NUM_TYPES = | Total number of bone types. |
Properties
int type#
Returns the type of the bone, one of the TYPE values.
float length#
Returns the length of the bone.
float width#
Returns the width of the bone, in meters.
vec3 prev_joint#
Returns the coordinates of the end of the bone, closest to the wrist (proximal).
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
vec3 next_joint#
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 bone.
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
vec3 direction#
Returns the normalized direction of the bone from wrist to tip.
Notice
All coordinates are relative to the origin of the Leap Motion coordinate system.
mat4 basis#
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. Increases in the upward direction.
- Z - Aligned with the longitudinal axis of the bone. Increases 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.
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 bone contains valid tracking data; otherwise, 0.
Members
Last update:
2020-07-31
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