Android Question GPS Vs Proximity

Discussion in 'Android Questions' started by DeviousD, May 29, 2015.

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  1. DeviousD

    DeviousD Member Licensed User


    I have a need to determine the location of other devices in the vicinity on the current device.

    I'm using HTTP push to send current device GPS coords to a mysql database with PHP backend.

    Using this PHP function i can get the distance away from me...

    function haversineGreatCircleDistance(
    $latitudeFrom, $longitudeFrom, $latitudeTo, $longitudeTo, $earthMeanRadius = 6371)
    $deltaLatitude = deg2rad($latitudeTo - $latitudeFrom);
    $deltaLongitude = deg2rad($longitudeTo - $longitudeFrom);
    $a = sin($deltaLatitude / 2) * sin($deltaLatitude / 2) +
    cos(deg2rad($latitudeFrom)) * cos(deg2rad(latitudeTo)) *
    sin($deltaLongitude / 2) * sin($deltaLongitude / 2);
    $c = 2 * atan2(sqrt($a), sqrt(1-$a));
    return $earthMeanRadius * $c;

    I can fetch devices that are within a certain distance from my PHP dataservice... but...

    How would i go about getting the bearing of where other devices are in relation to me and then plot them?

    I have used the GPS samples for Other projects and this works to a degree, Not sure the proximity samples will work as I'm not sure how to bring these elements together.

    Any suggestions on how to tackle this?
  2. Erel

    Erel Administrator Staff Member Licensed User

    Let the server return a list of the near devices coordinates. You can then use Location.DistanceTo and BearingTo to find those values.
    Peter Simpson likes this.
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