public boolean touchesIcon(final Geopoint tap, final Geopoint iconBase, @Nullable final ToScreenProjector toScreenCoordFunc) {
        if (tap == null || iconBase == null || toScreenCoordFunc == null) {
            return false;
        }
        ensureBmSizes();
        return GeoItemUtils.touchesPixelArea(tap, iconBase, bmWidth, bmHeight, xAnchor, yAnchor, toScreenCoordFunc);
    }
if the marker should rotate together with the map (flat mode) or should be displayed as billboard popup. Default is billboard.
main/src/main/java/cgeo/geocaching/models/geoitem/GeoIcon.java