kinect/codes/Azure-Kinect-Samples/body-tracking-samples/sample_unity_bodytracking/Assets/Scripts/Body.cs

using Microsoft.Azure.Kinect.BodyTracking;
using Microsoft.Azure.Kinect.Sensor;
using System;
using System.Numerics;
using UnityEngine;
using System.Runtime.Serialization;

// Class with relevant information about body
// bodyId and 2d and 3d points of all joints
[Serializable]
public struct Body : ISerializable
{
    public System.Numerics.Vector3[] JointPositions3D;

    public System.Numerics.Vector2[] JointPositions2D;

    public System.Numerics.Quaternion[] JointRotations;

    public JointConfidenceLevel[] JointPrecisions;

    public int Length;

    public uint Id;

    public Body(int maxJointsLength)
    {
        JointPositions3D = new System.Numerics.Vector3[maxJointsLength];
        JointPositions2D = new System.Numerics.Vector2[maxJointsLength];
        JointRotations = new System.Numerics.Quaternion[maxJointsLength];
        JointPrecisions = new JointConfidenceLevel[maxJointsLength];

        Length = 0;
        Id = 0;
    }

    public static Body DeepCopy(Body copyFromBody)
    {
        int maxJointsLength = copyFromBody.Length;
        Body copiedBody = new Body(maxJointsLength);

        for (int i = 0; i < maxJointsLength; i++)
        {
            copiedBody.JointPositions2D[i] = copyFromBody.JointPositions2D[i];
            copiedBody.JointPositions3D[i] = copyFromBody.JointPositions3D[i];
            copiedBody.JointRotations[i] = copyFromBody.JointRotations[i];
            copiedBody.JointPrecisions[i] = copyFromBody.JointPrecisions[i];
        }
        copiedBody.Id = copyFromBody.Id;
        copiedBody.Length = copyFromBody.Length;
        return copiedBody;
    }

    public void CopyFromBodyTrackingSdk(Microsoft.Azure.Kinect.BodyTracking.Body body, Calibration sensorCalibration)
    {
        Id = body.Id;
        Length = Microsoft.Azure.Kinect.BodyTracking.Skeleton.JointCount;

        for (int bodyPoint = 0; bodyPoint < Length; bodyPoint++)
        {
            // K4ABT joint position unit is in millimeter. We need to convert to meters before we use the values.
            JointPositions3D[bodyPoint] = body.Skeleton.GetJoint(bodyPoint).Position / 1000.0f;
            JointRotations[bodyPoint] = body.Skeleton.GetJoint(bodyPoint).Quaternion;
            JointPrecisions[bodyPoint] = body.Skeleton.GetJoint(bodyPoint).ConfidenceLevel;

            var jointPosition = JointPositions3D[bodyPoint];
            var position2d = sensorCalibration.TransformTo2D(
                jointPosition,
                CalibrationDeviceType.Depth,
                CalibrationDeviceType.Depth);

            if (position2d != null)
            {
                JointPositions2D[bodyPoint] = position2d.Value;
            }
            else
            {
                JointPositions2D[bodyPoint].X = Constants.Invalid2DCoordinate;
                JointPositions2D[bodyPoint].Y = Constants.Invalid2DCoordinate;
            }
        }
    }

    public Body(SerializationInfo info, StreamingContext context)
    {
        float[] JointPositions3D_X = (float[])info.GetValue("JointPositions3D_X", typeof(float[]));
        float[] JointPositions3D_Y = (float[])info.GetValue("JointPositions3D_Y", typeof(float[]));
        float[] JointPositions3D_Z = (float[])info.GetValue("JointPositions3D_Z", typeof(float[]));
        JointPositions3D = new System.Numerics.Vector3[JointPositions3D_X.Length];
        for (int i = 0; i < JointPositions3D_X.Length; i++)
        {
            JointPositions3D[i].X = JointPositions3D_X[i];
            JointPositions3D[i].Y = JointPositions3D_Y[i];
            JointPositions3D[i].Z = JointPositions3D_Z[i];
        }

        float[] JointPositions2D_X = (float[])info.GetValue("JointPositions2D_X", typeof(float[]));
        float[] JointPositions2D_Y = (float[])info.GetValue("JointPositions2D_Y", typeof(float[]));
        JointPositions2D = new System.Numerics.Vector2[JointPositions2D_X.Length];
        for (int i = 0; i < JointPositions2D_X.Length; i++)
        {
            JointPositions2D[i].X = JointPositions2D_X[i];
            JointPositions2D[i].Y = JointPositions2D_Y[i];
        }

        float[] JointRotations_X = (float[])info.GetValue("JointRotations_X", typeof(float[]));
        float[] JointRotations_Y = (float[])info.GetValue("JointRotations_Y", typeof(float[]));
        float[] JointRotations_Z = (float[])info.GetValue("JointRotations_Z", typeof(float[]));
        float[] JointRotations_W = (float[])info.GetValue("JointRotations_W", typeof(float[]));
        JointRotations = new System.Numerics.Quaternion[JointRotations_X.Length];
        for (int i = 0; i < JointRotations_X.Length; i++)
        {
            JointRotations[i].X = JointRotations_X[i];
            JointRotations[i].Y = JointRotations_Y[i];
            JointRotations[i].Z = JointRotations_Z[i];
            JointRotations[i].W = JointRotations_W[i];
        }

        uint[] ConfidenceLevel = (uint[])info.GetValue("ConfidenceLevel", typeof(uint[]));
        JointPrecisions = new JointConfidenceLevel[ConfidenceLevel.Length];
        for (int i = 0; i < ConfidenceLevel.Length; i++)
        {
            JointPrecisions[i] = (JointConfidenceLevel)ConfidenceLevel[i];
        }


        Length = (int)info.GetValue("Length", typeof(int));
        Id = (uint)info.GetValue("Id", typeof(uint));
    }

    public void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        float[] JointPositions3D_X = new float[Length];
        float[] JointPositions3D_Y = new float[Length];
        float[] JointPositions3D_Z = new float[Length];
        for (int i = 0; i < Length; i++)
        {
            JointPositions3D_X[i] = JointPositions3D[i].X;
            JointPositions3D_Y[i] = JointPositions3D[i].Y;
            JointPositions3D_Z[i] = JointPositions3D[i].Z;
        }
        info.AddValue("JointPositions3D_X", JointPositions3D_X, typeof(float[]));
        info.AddValue("JointPositions3D_Y", JointPositions3D_Y, typeof(float[]));
        info.AddValue("JointPositions3D_Z", JointPositions3D_Z, typeof(float[]));

        float[] JointPositions2D_X = new float[Length];
        float[] JointPositions2D_Y = new float[Length];
        for (int i = 0; i < Length; i++)
        {
            JointPositions2D_X[i] = JointPositions2D[i].X;
            JointPositions2D_Y[i] = JointPositions2D[i].Y;
        }
        info.AddValue("JointPositions2D_X", JointPositions2D_X, typeof(float[]));
        info.AddValue("JointPositions2D_Y", JointPositions2D_Y, typeof(float[]));

        float[] JointRotations_X = new float[Length];
        float[] JointRotations_Y = new float[Length];
        float[] JointRotations_Z = new float[Length];
        float[] JointRotations_W = new float[Length];
        for (int i = 0; i < Length; i++)
        {
            JointRotations_X[i] = JointRotations[i].X;
            JointRotations_Y[i] = JointRotations[i].Y;
            JointRotations_Z[i] = JointRotations[i].Z;
            JointRotations_W[i] = JointRotations[i].W;

        }
        info.AddValue("JointRotations_X", JointRotations_X, typeof(float[]));
        info.AddValue("JointRotations_Y", JointRotations_Y, typeof(float[]));
        info.AddValue("JointRotations_Z", JointRotations_Z, typeof(float[]));
        info.AddValue("JointRotations_W", JointRotations_W, typeof(float[]));

        uint[] ConfidenceLevels = new uint[Length];
        for (int i = 0; i < Length; i++)
        {
            ConfidenceLevels[i] = (uint)JointPrecisions[i];
        }
        info.AddValue("ConfidenceLevels", ConfidenceLevels, typeof(uint[]));

        info.AddValue("Length", Length, typeof(int));
        info.AddValue("Id", Id, typeof(uint));
    }
}