title: The boundary of many points on Google Map
body: <p>everyone. Recently, we have encountered a problem about the boundary on Google Map. </p>
  
  <p>We have received lots of points which are the objects as 'new google.maps.LatLng(lat,lng)'. Then, how to draw or make the boundary of this chunk. Or how to find the points (LatLng, used to draw the polygon) on the boundary, is there any JS arithmetic ? </p>
  
  <p>Just like one story: we receive many sheep(points) as presents, so how to build the sheepfold with clear boundary for them ? </p>
  
  <p>Thank you very much for any reply !!!</p>