title: Swift 3 Add custom annotation pin to MKMapSnapShotter snapshot
body: <p>I'm learning Swift 3 on my own, and my current learning project involves allowing the user to snap a photo and get a map snapshot with the current location pinned.</p>
  
  <p>I've relied on <a href="https://stackoverflow.com/questions/32121778/mkmapsnapshotoptions-adding-snapshot-of-custom-pin-annotation-view-or-uiview">this answer</a> from Aug 2015 and <a href="https://stackoverflow.com/questions/37964914/show-annotation-title-and-subtitle-in-custom-mkpinannotationview">this answer</a> from Jun 2016 for guidance, but I still can't find the right path.  </p>
  
  <p>Right now, I can...</p>
  
  <ol>
  <li>Get the photo from the buffer</li>
  <li>Get a map snapshot</li>
  </ol>
  
  <p>But I just can't place the pin.  I know that my code is incomplete and ineffective -- so this is more than just a debugging question.  Here is what I've been working with (as well as many variations based on the links above):</p>
  
  <pre><code>let snapShotter = MKMapSnapshotter(options: mapSnapshotOptions)
  
  snapShotter.start() {
  
      snapshot, error in
  
          guard let snapshot = snapshot else {
              return
          }
  
          let image = snapshot.image
          let annotation = MKPointAnnotation()
          annotation.coordinate = needleLocation  // is a CLLocationCoordinate2D
          annotation.title = "My Title"
  
          let annotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "annotation")
  
          // I want to push the final image to a global variable
          // can't figure out how to define finalImage as the pinned map
          self.myMap = finalImage
  
  
          } // close snapShotter.start
  </code></pre>
  
  <p>I've been stuck for days now, so I certainly would appreciate any insights.  Thanks!</p>