isUniqueEdge function
Implementation
bool isUniqueEdge(Vector3 start, Vector3 end, edges) {
final hash1 = "${start.x},${start.y},${start.z}-${end.x},${end.y},${end.z}";
final hash2 =
"${end.x},${end.y},${end.z}-${start.x},${start.y},${start.z}"; // coincident edge
if (edges.contains(hash1) == true || edges.contains(hash2) == true) {
return false;
} else {
edges.addAll([hash1, hash2]);
return true;
}
}