title: Modify a captured image in unity3d
body: <p>I have a plane which contain a <code>WebCamTexture</code> and a button to capture the image 
  <img src="https://i.stack.imgur.com/QyDEz.png" alt="enter image description here"></p>
  
  <p>script to capture the image</p>
  
  <pre><code>void CaptureAndSave () {
      Debug.Log (Camera_panel_script.webCameraTexture);
      Texture2D snap = new Texture2D(Camera_panel_script.webCameraTexture.width, Camera_panel_script.webCameraTexture.height);
      snap.SetPixels(Camera_panel_script.webCameraTexture.GetPixels());
      snap.Apply();
      Debug.Log (Application.persistentDataPath.ToString());
      System.IO.File.WriteAllBytes(
          Application.persistentDataPath+"/my_image.png",
          snap.EncodeToPNG()
          );
  }
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/Uukxf.png" alt="enter image description here"></p>
  
  <p>this is the resulted image </p>
  
  <p>how can i modify my code to add <code>the image</code> logo to my resulted picture ? so the captured image would look like this :</p>
  
  <p><img src="https://i.stack.imgur.com/FEu8W.png" alt="enter image description here"></p>