/// <summary>
/// Searches for an indexed face by iterating.
/// </summary>
/// <param name="index">The index of the face to return.</param>
/// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="index"/> is negative or too large.</exception>
/// <returns>The specified face.</returns>
public Face GetFace(Int32 index)
{
if (index < 0)
{
throw new ArgumentOutOfRangeException("index", index, "The given index cannot be negative.");
}
try
{
return(Faces.Skip(index).First());
}
catch (InvalidOperationException)
{
throw new ArgumentOutOfRangeException("index", index, "The given index is too large.");
}
}
public List <int[]> Edges()
{
var edgeConnectivities = new List <int[]>();
// Get face connectivities and close loop
var faceConnnectivities = new List <int[]>();
for (var i = 0; i < Faces.Count(); i++)
{
var numVertices = Faces[i] + 3;
i++;
faceConnnectivities.Add(Faces.Skip(i).Take(numVertices).Concat(Faces.Skip(i).Take(1)).ToArray());
i += numVertices - 1;
}
// Get distinct edges
var edges = new List <Tuple <int, int, string, string, double> >();
foreach (var conn in faceConnnectivities)
{
for (var i = 0; i < conn.Length - 1; i++)
{
var c1 = string.Join(",", Vertices.Skip(conn[i] * 3).Take(3).Select(x => Math.Round(x, 4).ToString()));
var c2 = string.Join(",", Vertices.Skip(conn[i + 1] * 3).Take(3).Select(x => Math.Round(x, 4).ToString()));
var length = Math.Pow(Vertices.Skip(conn[i] * 3).Take(1).First() - Vertices.Skip(conn[i + 1] * 3).Take(1).First(), 2) +
Math.Pow(Vertices.Skip(conn[i] * 3 + 1).Take(1).First() - Vertices.Skip(conn[i + 1] * 3 + 1).Take(1).First(), 2) +
Math.Pow(Vertices.Skip(conn[i] * 3 + 2).Take(1).First() - Vertices.Skip(conn[i + 1] * 3 + 2).Take(1).First(), 2);
length = Math.Sqrt(length);
if (edges.Any(e => (e.Item3 == c1 && e.Item4 == c2) |
(e.Item3 == c2 && e.Item4 == c1)))
{
edges.RemoveAll(x => (x.Item3 == c1 && x.Item4 == c2) || (x.Item3 == c2 && x.Item4 == c1));
}
else
{
if (conn[i] < conn[i + 1])
{
edges.Add(new Tuple <int, int, string, string, double>(conn[i], conn[i + 1], c1, c2, length));
}
else
{
edges.Add(new Tuple <int, int, string, string, double>(conn[i + 1], conn[i], c2, c1, length));
}
}
}
}
// Reorder the edges
var lengthsOfEdges = new List <double>();
double currentLength = 0;
var currentLoop = new List <int>();
var flatCoor = new List <string>();
currentLoop.Add(edges[0].Item1);
currentLoop.Add(edges[0].Item2);
flatCoor.Add(edges[0].Item3);
flatCoor.Add(edges[0].Item4);
edges.RemoveAt(0);
while (edges.Count > 0)
{
var commonVertex = flatCoor.Last();
var nextEdge = edges.Where(e => e.Item3 == commonVertex | e.Item4 == commonVertex).ToList();
if (nextEdge.Count > 0)
{
currentLoop.Add(nextEdge[0].Item3 == commonVertex ? nextEdge[0].Item2 : nextEdge[0].Item1);
flatCoor.Add(nextEdge[0].Item3 == commonVertex ? nextEdge[0].Item4 : nextEdge[0].Item3);
edges.Remove(nextEdge[0]);
currentLength += nextEdge[0].Item5;
}
else
{
// Next edge not found. Stop looking for more
break;
}
if (currentLoop[0] == currentLoop.Last())
{
currentLoop.RemoveAt(0);
edgeConnectivities.Add(currentLoop.ToArray());
lengthsOfEdges.Add(currentLength);
currentLength = 0;
currentLoop = new List <int>();
faceConnnectivities = new List <int[]>();
if (edges.Count > 0)
{
currentLoop.Add(edges[0].Item1);
currentLoop.Add(edges[0].Item2);
flatCoor.Add(edges[0].Item3);
flatCoor.Add(edges[0].Item4);
edges.RemoveAt(0);
}
}
}
// Sort based on length
var ordered = lengthsOfEdges
.Select((x, i) => new KeyValuePair <double, int>(x, i))
.OrderBy(x => x.Key)
.Select(x => x.Value)
.Reverse();
var sortedEdgeConnectivities = new List <int[]>();
foreach (var i in ordered)
{
sortedEdgeConnectivities.Add(edgeConnectivities[i]);
}
return(sortedEdgeConnectivities);
}
