/// <summary>
/// Impose alternating cuts on given vertex array.
/// </summary>
/// <param name="array">The vertex array.</param>
/// <param name="length">The number of vertices to sort.</param>
/// <param name="seed">Random seed used for pivoting.</param>
internal static void Alternate(Vertex[] array, int length, int seed = RANDOM_SEED)
{
var qs = new VertexSorter(array, seed);
int divider = length >> 1;
// Re-sort the array of vertices to accommodate alternating cuts.
if (length - divider >= 2)
{
if (divider >= 2)
{
qs.AlternateAxes(0, divider - 1, 1);
}
qs.AlternateAxes(divider, length - 1, 1);
}
}
/// <summary>
/// Test the polygon for duplicate vertices.
/// </summary>
internal static bool HasDuplicateVertices(IPolygon poly)
{
var logger = Log.Instance;
int horrors = 0;
var points = poly.Points.ToArray();
VertexSorter.Sort(points);
for (int i = 1; i < points.Length; i++)
{
if (points[i - 1] == points[i])
{
horrors++;
logger.Warning(String.Format("Found duplicate point {0}.", points[i]),
"PolygonValidator.HasDuplicateVertices()");
}
}
return(horrors > 0);
}
/// <summary>
/// Sorts the given vertex array by x-coordinate.
/// </summary>
/// <param name="array">The vertex array.</param>
/// <param name="seed">Random seed used for pivoting.</param>
internal static void Sort(Vertex[] array, int seed = RANDOM_SEED)
{
var qs = new VertexSorter(array, seed);
qs.QuickSort(0, array.Length - 1);
}