public void applyOptions() {
Double dRankSpacing = (Double) rankSpacing.getValue();
Double dSiblingSpacing = (Double) siblingSpacing.getValue();
DotLayoutEngineProperties dotLayoutEngineProperties = DotLayoutEngineProperties.getInstance();
dotLayoutEngineProperties.setRankSpacing(dRankSpacing.doubleValue());
dotLayoutEngineProperties.setSiblingSpacing(dSiblingSpacing.doubleValue());
}