How to increase distance with google maps api?

Question

I already googled trying to find the answer, but nothing.

I'm creating a site where user can search and choose a place with google geocoding api, then i get the bounds of that place, but then user should be able to increase those bounds.

For example, user could increase distance from that place in 5km, so i would be able to increase bounds in 5km.

This is the result when user seacrh for some place:

"geometry" : {
        "bounds" : {
           "northeast" : {
              "lat" : 42.15420480,
              "lng" : -6.19020910
           },
           "southwest" : {
              "lat" : 32.403740,
              "lng" : -31.2751580
           }
        },

Now i need to increase the bounds with 5km. How can i do that in javascript considering that i have to convert km into degrees?

Thank you very much.

EDIT

I tryed this thanks to @geocodezip but something is not qorking. I try as it says here at "Destination point given distance and bearing from start point", but something is not working right. This is the code:

//convert decimal to degree
function getDD2DMS(dms, type){
    var sign = 1, Abs=0;
    var days, minutes, secounds, direction;

    if(dms < 0)  { sign = -1; }
    Abs = Math.abs( Math.round(dms * 1000000.));
    //Math.round is used to eliminate the small error caused by rounding in the computer:
    //e.g. 0.2 is not the same as 0.20000000000284
    //Error checks
    if(type == 'lat' && Abs > (90 * 1000000)){
        //alert(' Degrees Latitude must be in the range of -90. to 90. ');
        return false;
    } else if(type == 'lng' && Abs > (180 * 1000000)){
        //alert(' Degrees Longitude must be in the range of -180 to 180. ');
        return false;
    }
    days = Math.floor(Abs / 1000000);
    minutes = Math.floor(((Abs/1000000) - days) * 60);
    secounds = ( Math.floor((( ((Abs/1000000) - days) * 60) - minutes) * 100000) *60/100000 ).toFixed();
    days = days * sign;
    if(type == 'lat') direction = days<0 ? 'S' : 'N';
    if(type == 'lng') direction = days<0 ? 'W' : 'E';
    //else return value     
    return (days * sign) + 'º ' + minutes + "' " + secounds + "'' " + direction;
}

//calculate
    var R = 6371; // km
    var d = 10; //km
    var brng = 0; //0 vertical, 90 horizontal
    var lat1 = (42.15420480).toRad();
    var lon1 = (-6.19020910).toRad();
    var lat2 = Math.asin( Math.sin(lat1)*Math.cos(d/R) + Math.cos(lat1)*Math.sin(d/R)*Math.cos(brng) );
    var lon2 = lon1 + Math.atan2(Math.sin(brng)*Math.sin(d/R)*Math.cos(lat1), Math.cos(d/R)-Math.sin(lat1)*Math.sin(lat2));

    console.log('lat2 = ' + getDD2DMS(lat2, 'lat'));
    console.log('lon2 = ' + getDD2DMS(lon2, 'lng'));

The result is not the same as the link. Help me. Thank you very much.

Answer 1

I do not fully understand your question, but you could try to draw a bounding box and send a search through using the bounds as a bias.

var bounds;
google.maps.event.addListener(drawingManager, 'rectanglecomplete', function (rectangle) {
     bounds = rectangle.getBounds();
     //search
     google.maps.event.addListener(rectangle, 'bounds_changed', function () {
            bounds = rectangle.getBounds();
            //search
     }
}

//this is a copy of the search function in my app
function codeAddress(type, geo) {
var bounds = map.getBounds(); //get the current map bounds (should not be greater than the bounding box)
geocoder.geocode({ 'address': geo, 'bounds': bounds }, function (results, status) { //geocode the lat/long of incoming with a bias towards the bounds
    if (status == google.maps.GeocoderStatus.OK) { //if it worked
        map.setCenter(results[0].geometry.location); //set the center of map to the results
        testBounds(); //test to make sure we are indeed in the bounds (have to do this because gmaps only allows for a BIAS of bounds and is not strict)
        if (mapInBounds == "yes") { //if it is inside bounds
            if (searchCount > 0) { //check to see if this is the first time searched, if not
                searchResult.setMap(null); //set old search result to not display on map
            } else { //if it is the first time
                searchCount++; //just interate
            }
            searchResult = new google.maps.Marker({ //create a new marker
                map: map, //add to current map
                position: results[0].geometry.location //set position to search results
            });
            document.getElementById("search_results").innerHTML = "<div id=\"searchResult\">" + geo + " <a href=\"#\" onclick=\"searchResultDeleteMe();\"><img src=\"images/delete.png\"/></a></div><br\>"; //add list div
        } else { //if location found was outside strict map bounds...
            displayMessage("Could not find within bounds."); //say so
        }

    } else { //if the entire geocode did not work
        alert(L6); //localization...
    }
});
}               //get the location of a lat/long or address
function codeLatLng(latlng) {
if (geocoder) {
    geocoder.geocode({ 'latLng': latlng }, function (results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
            if (results[1]) {
                document.getElementById("rgItem").innerHTML = results[0].formatted_address;
            }
            else {
                document.getElementById("rgItem").innerHTML = "Geocoder failed due to: " + status;
                document.getElementById("rgItem").innerHTML = "";
            }
        }
    });
}
}                   //get th