Displaying markers within a Bing maps Polygon

Question

I am using Bing maps to display markers on the map.

Now I am adding a functionality where I allow the user to draw a circle around any marker of his choice and let him specify the radius of the circle in kilometres.

I want the circle(polygon) to contain markers within the latitude/longitude bounds of that circle and the markers outside of the circle to disappear.

How do I achieve this?

Answer 1

You have provided no code.

However, I was involved in a similar project so I have an idea what you are talking about. SInce you are looking for custom polygon you can have a look at this link.

Another way to do it would be to the x,y coordinates of the marker and using Javascript to draw a circle around the map.

THIS JAVASCRIPT SHOULD HELP

function drawCircle(radius, origin) {
    var RadPerDeg = Math.PI / 180;
    var earthRadius = 3959;  
    var lat = origin.latitude * RadPerDeg;
    var lon = origin.longitude * RadPerDeg;
    var locs = new Array();
    var AngDist = parseFloat(radius) / earthRadius;
    for (x = 0; x <= 360; x++) { //making a 360-sided polygon
        var pLatitude, pLongitude;
        // With a nice, flat earth we could just say p2.Longitude = lon * sin(brng) and p2.Latitude = lat * cos(brng)
        // But it ain't, so we can't.  See http://www.movable-type.co.uk/scripts/latlong.html
        brng = x * RadPerDeg;
        pLatitude = Math.asin(Math.sin(lat) * Math.cos(AngDist) + Math.cos(lat) * Math.sin(AngDist) * Math.cos(brng)); //still in radians
        pLongitude = lon + Math.atan2(Math.sin(brng) * Math.sin(AngDist) * Math.cos(lat), Math.cos(AngDist) - Math.sin(lat) * Math.sin(pLatitude));
        pLatitude = pLatitude / RadPerDeg;
        pLongitude = pLongitude / RadPerDeg;
        locs.push(new MM.Location(pLatitude, pLongitude));
    };
    circle = new MM.Polyline(locs, { visible: true, strokeThickness: 2, strokeDashArray: "1", strokeColor: new MM.Color(200, 0, 0, 200, 0) });
    map.entities.push(circle);
};