gistfile1.txt

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.VR;
using Valve.VR;

public class Cubeoverlay : MonoBehaviour 
{

  public GameObject Cube;
  private RenderTexture renderTexture { get; set; }
  private ulong OverlayHandle;
  public Camera mainCamera;
  private uint openvrid;

  void Start()
  {

    OverlayHandle = Valve.VR.OpenVR.k_ulOverlayHandleInvalid;

    HmdColor_t hmdColor_T = new HmdColor_t();

    hmdColor_T.a = 1;
    hmdColor_T.b = 1;
    hmdColor_T.g = 1;
    hmdColor_T.r = 1;

    Debug.Log(gameObject.name);

    Debug.Log(OverlayHandle.ToString());

    OpenVR.Overlay.CreateOverlay(gameObject.name, gameObject.name, ref OverlayHandle);

    OpenVR.Overlay.SetOverlayRenderModel(OverlayHandle, Cube.name, ref hmdColor_T);

    OpenVR.Overlay.ShowOverlay(OverlayHandle);
    RenderTexture renderTexture = new RenderTexture(1000, 1000, 1000);
    mainCamera.targetTexture = renderTexture;

    SteamVR_Camera Cam = SteamVR_Render.Top();
    SteamVR_Utils.RigidTransform offset = new SteamVR_Utils.RigidTransform(transform);
    offset.pos.x /= Cam.origin.localScale.x;
    offset.pos.y /= Cam.origin.localScale.y;
    offset.pos.z /= Cam.origin.localScale.z;
    HmdMatrix34_t matrix = offset.ToHmdMatrix34();
    
    OpenVR.Overlay.SetOverlayTransformTrackedDeviceRelative(OverlayHandle, OpenVR.k_unTrackedDeviceIndexInvalid, ref matrix);
    
    Texture_t overlayTexture = new Texture_t();
    overlayTexture.handle = renderTexture.GetNativeTexturePtr();

    OpenVR.Overlay.SetOverlayTexture(OverlayHandle, ref overlayTexture);

  }
 }