Need Help Calculating Longitude And Latitude Midpoint Using Javascript From Php Values

I am currently working on a project and have run into quite a snag. I am running a mapping application using the google maps API and I need to calculate the midpoint between two po

Solution 1:

in PHP

function midpoint ($lat1, $lng1, $lat2, $lng2) {

    $lat1= deg2rad($lat1);
    $lng1= deg2rad($lng1);
    $lat2= deg2rad($lat2);
    $lng2= deg2rad($lng2);

    $dlng = $lng2 - $lng1;
    $Bx = cos($lat2) * cos($dlng);
    $By = cos($lat2) * sin($dlng);
    $lat3 = atan2( sin($lat1)+sin($lat2),
    sqrt((cos($lat1)+$Bx)*(cos($lat1)+$Bx) + $By*$By ));
    $lng3 = $lng1 + atan2($By, (cos($lat1) + $Bx));
    $pi = pi();
    return ($lat3*180)/$pi .' '. ($lng3*180)/$pi;
}

Solution 2:

function distance($lat1, $lon1, $lat2, $lon2, $unit) { 

  $theta = $lon1 - $lon2; 
  $dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) +  cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta)); 
  $dist = acos($dist); 
  $dist = rad2deg($dist); 
  $miles = $dist * 60 * 1.1515;
  $unit = strtoupper($unit);

  if ($unit == "K") {
    return ($miles * 1.609344); 
  } elseif ($unit == "N") {
      return ($miles * 0.8684);
    } else {
        return $miles;
      }
}

This function will help you

Solution 3:

Use Openlayers and it helps to do this. http://www.openlayers.org/

Solution 4:

For a javascript version I converted @vineesh's answer.

functionmidpoint ($lat1, $lng1, $lat2, $lng2) {
    $lat1 = $lat1 * 0.017453292519943295;
    $lng1 = $lng1 * 0.017453292519943295;
    $lat2 = $lat2 * 0.017453292519943295;
    $lng2 = $lng2 * 0.017453292519943295;

    $dlng = $lng2 - $lng1;
    $Bx = Math.cos($lat2) * Math.cos($dlng);
    $By = Math.cos($lat2) * Math.sin($dlng);
    $lat3 = Math.atan2( Math.sin($lat1)+Math.sin($lat2),
    Math.sqrt((Math.cos($lat1)+$Bx)*(Math.cos($lat1)+$Bx) + $By*$By ));
    $lng3 = $lng1 + Math.atan2($By, (Math.cos($lat1) + $Bx));
    $pi = 3.141592653589793;
    $lat = ($lat3*180)/$pi;
    $lng = ($lng3*180)/$pi;
    return [$lat,$lng];
}