How do I find the the exact lat/lng coordinates of a birdseye scene in Virtual Earth?

Question

I'm trying to find the latitude and longitude of the corners of my map while in birdseye view. I want to be able to plot pins on the map, but I have hundreds of thousands of addresses that I want to be able to limit to the ones that need to show on the map.

In normal view, VEMap.GetMapView().TopLeftLatLong and .BottomRightLatLong return the coordinates I need; but in Birdseye view they return blank (or encrypted values). The SDK recommends using VEBirdseyeScene.GetBoundingRectangle(), but this returns bounds of up to two miles from the center of my scene which in major cities still returns way too many addresses.

In previous versions of the VE Control, there was an undocumented VEDecoder object I could use to decrypt the LatLong values for the birdseye scenes, but this object seems to have disappeared (probably been renamed). How can I decode these values in version 6.1?

Answer 1

Here's the code for getting the Center Lat/Long point of the map. This method works in both Road/Aerial and Birdseye/Oblique map styles.

function GetCenterLatLong()
        {
            //Check if in Birdseye or Oblique Map Style
            if (map.GetMapStyle() == VEMapStyle.Birdseye || map.GetMapStyle() == VEMapStyle.BirdseyeHybrid)
            {
                //IN Birdseye or Oblique Map Style


                //Get the BirdseyeScene being displayed
                var birdseyeScene = map.GetBirdseyeScene();


                //Get approximate center coordinate of the map
                var x = birdseyeScene.GetWidth() / 2;
                var y = birdseyeScene.GetHeight() / 2;

                // Get the Lat/Long 
                var center = birdseyeScene.PixelToLatLong(new VEPixel(x,y), map.GetZoomLevel());

                // Convert the BirdseyeScene LatLong to a normal LatLong we can use
                return (new _xy1).Decode(center);
            }
            else
            {
                // NOT in Birdseye or Oblique Map Style
                return map.GetCenter();
            }
        } 

This code was copied from here: http://pietschsoft.com/post/2008/06/Virtual-Earth-Get-Center-LatLong-When-In-Birdseye-or-Oblique-Map-Style.aspx