fonction intersection

	public void intersection(AbstractImage image1, AbstractImage image2) {

		Iterator<NodeState> it1 = image1.iterator();
		Iterator<NodeState> it2 = image2.iterator();
		Iterator<NodeState> it3 = this.iterator();

		it3.clear();

		if (!it1.isEmpty() && !it2.isEmpty()){
			intersectionR(it1, it2, it3);
		}

	}

	private void intersectionR(Iterator<NodeState> it1, Iterator<NodeState> it2, Iterator<NodeState> itThis) {
		if (!it1.isEmpty() && !it2.isEmpty()){
			NodeState ns1 = it1.getValue();
			NodeState ns2 = it2.getValue();

			if (ns1.equals(NodeState.valueOf(0)) || ns2.equals(NodeState.valueOf(0))) {
				itThis.addValue(NodeState.valueOf(0));
			}
			else if (ns1.equals(NodeState.valueOf(1)) && ns2.equals(NodeState.valueOf(1))) {
				itThis.addValue(NodeState.valueOf(1));
			}
			else if (ns1.equals(NodeState.valueOf(2)) && ns2.equals(NodeState.valueOf(2))) {
				itThis.addValue(NodeState.valueOf(2));
			}
			else {
				itThis.addValue(NodeState.valueOf(2));
				if (ns1.equals(NodeState.valueOf(1))) {
					it1.goLeft();
					it1.addValue(NodeState.valueOf(1));
					it1.goUp();
					it1.goRight();
					it1.addValue(NodeState.valueOf(1));
					it1.goUp();
				} else {
					it2.goLeft();
					it2.addValue(NodeState.valueOf(1));
					it2.goUp();
					it2.goRight();
					it2.addValue(NodeState.valueOf(1));
					it2.goUp();
				}
			}

			it1.goLeft();
			it2.goLeft();
			itThis.goLeft();
			intersectionR(it1, it2, itThis);
			it1.goUp();
			it2.goUp();
			itThis.goUp();
			it1.goRight();
			it2.goRight();
			itThis.goRight();
			intersectionR(it1, it2, itThis);
			it1.goUp();
			it2.goUp();
			itThis.goUp();

		}
	}