public Builder setXAnchor(final float xAnchor) {
            this.xAnchor = Math.min(1f, Math.max(0f, xAnchor));
            return this;
        }
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