public static IPoly RemoveDuplicateVerticies(IPoly poly)
{
List <Vector3> output = new List <Vector3>();
for (int i = 0; i < poly.Resolution; i++)
{
if (output.Count == 0)
{
output.Add(poly.GetPoint(i));
}
else
{
Vector3 point = poly.GetPoint(i);
Vector3 last = output[output.Count - 1];
if (!Math3d.Compare(point, last))
{
output.Add(point);
}
}
}
if (Math3d.Compare(output[0], output[output.Count - 1]))
{
output.RemoveAt(0);
}
return(poly.Clone(output.ToArray()));
}
/// <summary>
/// Create a polygon from a set of edges
/// For this algorithm to work as expected, the edges must wrap to form a polygon
/// Optimize output will merge consecutive edges with have the same line
/// </summary>
/// <param name="edges"></param>
/// <param name="constructor"></param>
/// <param name="optimizeOutput"></param>
/// <returns></returns>
public static IPoly GetPolygonFromEdges(IEnumerable <IEdge> edges, Func <IEnumerable <IEdge>, IPoly> constructor = null, bool optimizeOutput = true)
{
if (constructor == null)
{
constructor = (x) => new EdgePoly(x);
}
//create a hash set of all edges
HashSet <IEdge> hashSet = new HashSet <IEdge>(edges);
IEdge current = hashSet.First();
DoubleLinkNode <IEdge> currentNode = new DoubleLinkNode <IEdge>(current);
DoubleLinkNode <IEdge> firstNode = currentNode;
hashSet.Remove(current);
while (hashSet.Count > 0)
{
//find next node
IEdge next = hashSet.FirstOrDefault(x => Math3d.Compare(current.B, x.A));
//error check
if (next == null)
{
return(null);
}
//remove the node from the hash set
hashSet.Remove(next);
//create the next link node
currentNode.next = new DoubleLinkNode <IEdge>(next);
currentNode.next.previous = currentNode;
//advance the search space
current = next;
currentNode = currentNode.next;
}
//link ends
currentNode.next = firstNode;
firstNode.previous = currentNode;
if (optimizeOutput)
{
//rotate list to find good canidate for first node
for (currentNode = firstNode.next; currentNode != firstNode; currentNode = currentNode.next)
{
if (!IsParallel(currentNode.previous.value, currentNode.value))
{
break;
}
}
firstNode = currentNode;
//break link to prevent infinate loops over bad geometry
firstNode.previous.next = null;
firstNode.previous = null;
var last = firstNode;
//eliminate extra edges
for (var node = firstNode; node != null; node = node.next)
{
if (node != null)
{
last = node;
}
while (node.next != null && IsParallel(node.value, node.next.value))
{
node.value = new Edge(node.value.A, node.next.value.B);
node.next = node.next.next;
}
}
//relink ends
last.next = firstNode;
firstNode.previous = last;
}
//construct output to ngon
List <IEdge> outputList = new List <IEdge>();
outputList.Add(firstNode.value);
for (var node = firstNode.next; node != firstNode; node = node.next)
{
outputList.Add(node.value);
}
return(constructor(outputList));
}
