Compare photo location to record location

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This example demonstrates how to compare the geotagged location of an attached photo with the location of the record to alert the user if there may be an issue. NOTE: The LATITUDE and LONGITUDE functions will only return values if a record's geometry type is set to Point, and there is a location set. Unless you have enabled Lines and Polygons for your app, the Point type will be the only available geometry type for records in the app.

// source: https://www.geodatasource.com/developers/javascript
function findDistance(lat1, lon1, lat2, lon2, unit) {
  var radlat1 = Math.PI * lat1 / 180;
  var radlat2 = Math.PI * lat2 / 180;
  var theta = lon1 - lon2;
  var radtheta = Math.PI * theta / 180;
  var dist = Math.sin(radlat1) * Math.sin(radlat2) + Math.cos(radlat1) * Math.cos(radlat2) * Math.cos(radtheta);
  dist = Math.acos(dist);
  dist = dist * 180 / Math.PI;
  dist = dist * 60 * 1.1515;
  if (unit == "K") {
    dist = dist * 1.609344;
  }
  if (unit == "N") {
    dist = dist * 0.8684;
  }
  return dist;
}

function validateDistance(event) {
  if (event.value.latitude && event.value.longitude) {
    var kilometers = findDistance(event.value.latitude, event.value.longitude, LATITUDE(), LONGITUDE(), 'K');
    var meters = Math.round(kilometers * 1000);
    if (meters > 20) {
      ALERT('This photo is over 20 meters from the record location. (' + meters + ' meters)');
    }
  }
}

ON('load-record', function(event) {
  // loop through the photo fields
  DATANAMES('PhotoField').forEach(function(dataName) {
    // listen for add-photo event
    ON('add-photo', dataName, validateDistance);
  });
});

Updated 6 months ago