Android Question Fix marker on screen while map rotates (like Google Maps Navigation)

    'LastLocation
    If Not(LastLocation.IsInitialized) Then
        Dim CameraPosition1 = GoogleMaps1.CameraPosition, NewCameraPosition As CameraPosition
        NewCameraPosition.Initialize2(Location1.Latitude, Location1.Longitude, CameraPosition1.Zoom, CameraPosition1.Bearing, CameraPosition1.Tilt)
        GoogleMaps1.AnimateCamera(NewCameraPosition)
        LastLocation = Location1
    End If

Dim gpsLatLng As LatLng = mo.Marker.Position
Dim jo As JavaObject = gmap
Dim projection As JavaObject = jo.RunMethod("getProjection", Null)
Dim visibleRegion As JavaObject = projection.RunMethod("getVisibleRegion", Null)
Dim latLngBounds As JavaObject = visibleRegion.GetField("latLngBounds")
Dim southwest As JavaObject = latLngBounds.GetField("southwest")
Dim northeast As JavaObject = latLngBounds.GetField("northeast")
Dim minLat As Double = southwest.GetField("latitude")
Dim maxLat As Double = northeast.GetField("latitude")
Dim bearing As Float = mo.Course
Dim LatSpan25 As Double = (maxLat - minLat) * 0.25
Dim angleRad As Double = bearing * (cPI / 180)
Dim EarthRadius As Double = 6378137
Dim MeterPerDegreeLat As Double = (cPI / 180) * EarthRadius
Dim MeterPerDegreeLng As Double = MeterPerDegreeLat * Cos(gpsLatLng.Latitude * (cPI / 180))
Dim LatSpan25Meters As Double = LatSpan25 * MeterPerDegreeLat
Dim LngSpanCompensated As Double = LatSpan25Meters / MeterPerDegreeLng
Dim newLatOffset As Double = LatSpan25 * Cos(angleRad)
Dim newLngOffset As Double = LngSpanCompensated * Sin(angleRad)
Dim newLat As Double = gpsLatLng.Latitude + newLatOffset
Dim newLng As Double = gpsLatLng.Longitude + newLngOffset
Dim cp As CameraPosition
cp.Initialize2(newLat, newLng, zoomLevel, bearing, 60)
gmap.animatecamera(cp)

Sub GetLatLngAt25PercentFromBottom(markerPos As LatLng, zoom As Float, bearing As Float) As ResumableSub
    ' Step 1: center the invisible map on the marker with the given bearing and zoom
    Dim cp As CameraPosition
    cp.Initialize2(markerPos.Latitude, markerPos.Longitude, zoom, bearing, 0)
    gmapcalc.MoveCamera(cp)
    ' Step 2: wait until the invisible map has finished moving
    Wait For (WaitMapIdle) Complete (ok As Boolean)
    ' Step 3: calculate the screen coordinates of the point at 25% from the bottom
    Dim mapWidth As Int = PnlMapCalc.Width ' panels containing the invisible map
    Dim mapHeight As Int = PnlMapCalc.Height
    Dim screenX As Int = mapWidth / 2
    Dim screenY As Int = mapHeight * 0.25
    Dim joMap As JavaObject = gmapcalc
    Dim projection As JavaObject = joMap.RunMethod("getProjection", Null)
    Dim pointClass As JavaObject
    pointClass.InitializeNewInstance("android.graphics.Point", Array(screenX, screenY))
    Dim targetLatLng As JavaObject = projection.RunMethod("fromScreenLocation", Array(pointClass))
    Dim result As LatLng
    result.Initialize(targetLatLng.GetField("latitude"), targetLatLng.GetField("longitude"))
    Return result
End Sub