private ArrayList<Vertex> GetNeighboursVertexes(Vertex vertex) {
ArrayList<Vertex> neighboursVertexes = new ArrayList();
HalfEdge startEdge = vertex.getHalfEdge();
HalfEdge currentEdge = startEdge;
do {
neighboursVertexes.add(currentEdge.getOppositeHalfEdge().getStartVertex());
currentEdge = currentEdge.getOppositeHalfEdge().getNextHalfEdge();
} while (currentEdge != startEdge);
return neighboursVertexes;
}