Redrawing bitmap on Google Maps v2 for Android

Question

In this scenario I want to draw a bitmap on Google Maps using gms v2 and each user position update enforces bitmap update. Currently I use following code snippet:

public void init(){
    result = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    canvas = new Canvas(result);
}

public void update(){
    // draw on canvas ...
    draw(result);
}

public void draw(Bitmap modifiedBmp) {
    if (overlay != null) {
        overlay.remove();
    }

    BitmapDescriptor descriptor = BitmapDescriptorFactory.fromBitmap(modifiedBmp);
    overlay = map.addGroundOverlay(new GroundOverlayOptions().image(descriptor).positionFromBounds(bounds).zIndex(100));
} 

The update() method is called each second. I find this approach extremely inefficient and I'm searching for a better solution (i.e. that doesn't require to add/remove overlay after each update). Drawing primitives on map using addPolygon(...) and addPolyline(...) isn't an option because I require drawing capabilities not present in standard api.

Answer 1

One optimization could be to check if the new position is the same as the old one and don't redraw if that is the case. Also I don't think that the descriptor need to be created each time.

Another approach for moving markers is described here. It's the one from the official sample.

Answer 2

I'm not sure if this is what you want, but this is how I used custom bitmaps in Google Maps.

The marker code:

BitmapDescriptor iconBitmap = BitmapDescriptorFactory
                    .fromResource(R.drawable.item_map_marker);

MarkerOptions options = new MarkerOptions();
options.position(new LatLng(hs.lat, hs.lng));
options.title(hs.sitename);
options.snippet(hs.street + ", " + hs.suburb);
options.icon(iconBitmap);

mMap.addMarker(options);

The tooltip adapter:

public class MyInfoWindowAdapter implements InfoWindowAdapter {

    public interface OnRenderCustomInfoWindow {

        public void onRender(Marker marker, View mWindow);
    }

    private View                     mWindow;

    private OnRenderCustomInfoWindow mRenderer;

    public MyInfoWindowAdapter(Context context, 
            OnRenderCustomInfoWindow onRender) {
        mRenderer = onRender;
        mWindow = LayoutInflater.from(context).inflate(
            R.layout.view_services_map_infowindow, null);
    }

    @Override
    public View getInfoWindow(Marker marker) {
        mRenderer.onRender(marker, mWindow);
        return mWindow;
    }

    @Override
    public View getInfoContents(Marker marker) {
        return null;
    }
}