'Declaration
 
Public Overloads Shared Function GetEdgesWithoutDuplicates( _
   ByVal polygons() As SilhoTriangle, _
   ByVal numVerts As Integer, _
   ByVal skipBorderEdges As Boolean _
) As Integer(,)

public static int[,] GetEdgesWithoutDuplicates( 
   SilhoTriangle[] polygons,
   int numVerts,
   bool skipBorderEdges
)

The rectangular array of the resulting - unique - edges. First and second indices are the edge vertex indices, third and fourth are the parent triangle indices. Fourth index can be -1 for edges with only one parent triangle.