VIVE-OpenXR-Unity/com.htc.upm.vive.openxr/OpenXRHandTracking/Samples~/Scripts/RenderHand.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using VIVE.HandTracking;

namespace VIVE.HandTracking.Sample
{
    public class RenderHand : MonoBehaviour
    {
        // Links between keypoints, 2*i & 2*i+1 forms a link.
        // keypoint index: 1: palm, 2-5: thumb, 6-10: index, 11-15: middle, 16-20: ring, 21-25: pinky
        // fingers are counted from bottom to top
        private static int[] Connections = new int[] {
    1,  2,  1,  6,  1,  11, 1,  16, 1, 21,  // palm and finger starts
    2,  6,  6,  11, 11, 16, 16, 21,         // finger starts
    2,  3,  3,  4,  4,  5,                  // thumb
    6,  7,  7,  8,  8,  9,  9,  10,                  // index
    11, 12, 12, 13, 13, 14, 14, 15,                 // middle
    16, 17, 17, 18, 18, 19, 19, 20,                // ring
    21, 22, 22, 23, 23, 24, 24, 25                 // pinky
  };
        [Tooltip("Draw left hand if true, right hand otherwise")]
        public bool isLeft = false;
        [Tooltip("Use inferred or last-known posed when hand loses tracking if true.")]
        public bool allowUntrackedPose = false;
        [Tooltip("Default color of hand points")]
        public Color pointColor = Color.green;
        [Tooltip("Default color of links between keypoints in skeleton mode")]
        public Color linkColor = Color.white;
        [Tooltip("Material for hand points and links")]
        [SerializeField]
        private Material material = null;
        private XrHandJointsMotionRangeEXT MotionType = XrHandJointsMotionRangeEXT.XR_HAND_JOINTS_MOTION_RANGE_MAX_ENUM_EXT;
        [Tooltip("Type of hand joints range of motion")]
        [ReadOnly] public string HandJointsMotionRange;

        private List<GameObject> points = new List<GameObject>();
        // list of links created (only for skeleton)
        private List<GameObject> links = new List<GameObject>();
        // Start is called before the first frame update
        private XrHandJointLocationEXT[] HandjointLocations = new
            XrHandJointLocationEXT[(int)XrHandJointEXT.XR_HAND_JOINT_MAX_ENUM_EXT];
        // shared material for all point objects
        private Material pointMat = null;
        // shared material for all link objects
        private Material linkMat = null;
        private void Start()
        {
            HandManager.StartFrameWork(isLeft);
            pointMat = new Material(material);
            if (isLeft)
            {
                pointColor = Color.blue;
            }
            else
            {
                pointColor = Color.red;
            }
            pointMat.color = pointColor;
            linkMat = new Material(material);
            linkMat.color = linkColor;

            for (int i = 0; i < (int)XrHandJointEXT.XR_HAND_JOINT_MAX_ENUM_EXT; i++)
            {
                var go = GameObject.CreatePrimitive(PrimitiveType.Sphere);
                go.name = ((XrHandJointEXT)i).ToString();
                go.transform.parent = transform;
                go.transform.localScale = Vector3.one * 0.012f;
                go.SetActive(false);
                points.Add(go);
                go.transform.position = new Vector3((float)i * 0.1f, 0, 0);
                // handle layer
                go.layer = gameObject.layer;
                // handle material
                go.GetComponent<Renderer>().sharedMaterial = pointMat;
            }

            // create game objects for links between keypoints, only used in skeleton mode
            for (int i = 0; i < Connections.Length; i += 2)
            {
                var go = GameObject.CreatePrimitive(PrimitiveType.Cylinder);
                go.name = "link" + i;
                go.transform.parent = transform;
                go.transform.localScale = Vector3.one * 0.005f;
                go.SetActive(false);
                links.Add(go);
                // handle layer
                go.layer = gameObject.layer;
                // handle material
                go.GetComponent<Renderer>().sharedMaterial = linkMat;
            }
        }
        // Update is called once per frame
        private void Update()
        {
            if (HandManager.GetJointLocation(isLeft, out HandjointLocations, ref MotionType))
            {
                UpdateJointLocation();
                switch (MotionType)
                {
                    case XrHandJointsMotionRangeEXT.XR_HAND_JOINTS_MOTION_RANGE_UNOBSTRUCTED_EXT:
                        HandJointsMotionRange = "UNOBSTRUCTED";
                        break;
                    case XrHandJointsMotionRangeEXT.XR_HAND_JOINTS_MOTION_RANGE_CONFORMING_TO_CONTROLLER_EXT:
                        HandJointsMotionRange = "CONTROLLER";
                        break;
                    default:
                        HandJointsMotionRange = "";
                        break;
                }
            }
            else
            {
                for (int i = 0; i < points.Count; i++)
                {
                    var go = points[i];
                    go.SetActive(false);
                }

                for (int i = 0; i < links.Count; i++)
                {
                    var link = links[i];
                    link.SetActive(false);
                }
            }
        }

        private void UpdateJointLocation()
        {
            for (int i = 0; i < points.Count; i++)
            {
                var go = points[i];
                XrQuaternionf orientation;
                XrVector3f position;
                float radius = HandjointLocations[i].radius;
                if (allowUntrackedPose) //Use inferred or last-known pose when lost tracking 
                {
                    orientation = HandjointLocations[i].pose.orientation;
                    position = HandjointLocations[i].pose.position;
                    go.transform.localPosition = new Vector3(position.x, position.y, -position.z);
                    go.SetActive(true);
                }
                else
                {
                    if ((HandjointLocations[i].locationFlags & (ulong)XrSpaceLocationFlags.XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT) != 0)
                    {
                        orientation = HandjointLocations[i].pose.orientation;
                    }
                    if ((HandjointLocations[i].locationFlags & (ulong)XrSpaceLocationFlags.XR_SPACE_LOCATION_POSITION_TRACKED_BIT) != 0)
                    {
                        position = HandjointLocations[i].pose.position;
                        go.transform.localPosition = new Vector3(position.x, position.y, -position.z);
                        go.SetActive(true);
                    }
                    else
                    {
                        UnityEngine.Debug.Log("Lost tracking");
                        go.SetActive(false);
                    }
                }
            }

            for (int i = 0; i < links.Count; i++)
            {
                var link = links[i];
                var pose1 = points[Connections[i * 2]].transform.position;
                var pose2 = points[Connections[i * 2 + 1]].transform.position;

                // calculate link position and rotation based on points on both end
                link.SetActive(true);
                link.transform.position = (pose1 + pose2) / 2;
                var direction = pose2 - pose1;
                link.transform.rotation = Quaternion.FromToRotation(Vector3.up, direction);
                link.transform.localScale = new Vector3(0.006f, direction.magnitude / 2f - 0.0051f, 0.006f);
            }

        }
        private void OnDestroy()
        {
            HandManager.StopFrameWork(isLeft);
            UnityEngine.Debug.Log("OnDestroy");
        }

        //public void setHandVisible(bool isVisible)
        //{
        //    Hand.SetActive(isVisible);
        //}
    }

}