Keijiro's AprilTag for scene tracking

PictureTest.cs

using UnityEngine;
using System.Linq;
using UI = UnityEngine.UI;
using AprilTag;

sealed class PicTest : MonoBehaviour
{
    [SerializeField] Vector2Int _resolution = new Vector2Int(1280, 720);
    [SerializeField] int _decimation = 4;
    [SerializeField] float _tagSize = 0.05f;
    [SerializeField] UI.RawImage _picPreview = null;
    [SerializeField] Material _tagMaterial = null;
    [SerializeField] UI.Text _debugText = null;
    public Texture2D sourceImage;
    Color32[] _readBuffer;
    public RenderTexture myRenderTexture;


    // AprilTag detector and drawer
    AprilTag.TagDetector _detector;
    TagDrawer _drawer;

    void Start()
    {
        _readBuffer = new Color32[_resolution.x * _resolution.y];
        _picPreview.texture = sourceImage;
        
        // Detector and drawer
        _detector = new AprilTag.TagDetector(_resolution.x, _resolution.y, _decimation);
        _drawer = new TagDrawer(_tagMaterial);

    }

    void OnDestroy()
    {
        // Destroy(sourceImage);
        // Destroy(myRenderTexture);

        _detector.Dispose();
        _drawer.Dispose();
    }

    void Update()
    {
        // Image conversion and buffering
        sourceImage = toTexture2D(myRenderTexture);
        _readBuffer = sourceImage.GetPixels32();
        

        // AprilTag detection
        var fov = GetComponent<Camera>().fieldOfView * Mathf.Deg2Rad;
        _detector.ProcessImage(_readBuffer, fov, _tagSize);

        Destroy(sourceImage);

        // Detected tag visualization
        foreach (var tag in _detector.DetectedTags)
        {
            _drawer.Draw(tag.ID, tag.Position, tag.Rotation, _tagSize);
            Debug.LogFormat("ID: {0}, Pos: {1}, Rot: {2}", tag.ID, tag.Position, tag.Rotation);

        }

        // Profile data output (with 30 frame interval)
        if (Time.frameCount % 30 == 0)
            _debugText.text = _detector.ProfileData.Aggregate
              ("Profile (usec)", (c, n) => $"{c}\n{n.name} : {n.time}");
    }
    private Texture2D toTexture2D(RenderTexture rt)
    {
        var texture = new Texture2D(rt.width, rt.height, TextureFormat.ARGB32, false);
        RenderTexture.active = rt;
        texture.ReadPixels(new Rect(0, 0, rt.width, rt.height), 0, 0);
        texture.Apply();

        RenderTexture.active = null;

        return texture;
    }

}