/* Navigation */
/**
* Report neighbor opposite the given vertex of simplex.
* @param vertex a vertex of simplex
* @param simplex we want the neighbor of this Simplex
* @return the neighbor opposite vertex of simplex; null if none
* @throws IllegalArgumentException if vertex is not in this Simplex
*/
public Simplex neighborOpposite(Object vertex, Simplex simplex)
{
if (!simplex.contains(vertex))
{
throw new InvalidOperationException("Bad vertex; not in simplex");
}
for (Iterator it = ((Set)_neighbors.get(simplex)).iterator(); it.hasNext();)
{
Simplex s = (Simplex)it.next();
for (Iterator otherIt = simplex.iterator(); otherIt.hasNext();)
{
var v = otherIt.next();
if (v.Equals(vertex))
{
continue;
}
if (!s.contains(v))
{
s = null;
break;
}
}
if (s == null)
{
continue;
}
return(s);
}
return(null);
}
/**
* Draw all the empty circles (one for each triangle) of the DT.
*/
public void drawAllCircles()
{
// Loop through all triangles of the DT
for (Iterator it = dt.iterator(); it.hasNext();)
{
Simplex triangle = (Simplex)it.next();
for (Iterator otherIt = initialTriangle.iterator(); otherIt.hasNext();)
{
Pnt p = (Pnt)otherIt.next();
if (triangle.contains(p))
{
triangle = null;
break;
}
}
if (triangle != null)
{
Pnt c = Pnt.circumcenter((Pnt[])triangle.toArray(new Pnt[0]));
double radius = c.subtract((Pnt)triangle.iterator().next()).magnitude();
draw(c, radius, null);
}
}
}
/* Navigation */
/**
* Report neighbor opposite the given vertex of simplex.
* @param vertex a vertex of simplex
* @param simplex we want the neighbor of this Simplex
* @return the neighbor opposite vertex of simplex; null if none
* @throws IllegalArgumentException if vertex is not in this Simplex
*/
public Simplex neighborOpposite(Object vertex, Simplex simplex)
{
if (!simplex.contains(vertex))
throw new InvalidOperationException("Bad vertex; not in simplex");
for (Iterator it = ((Set)_neighbors.get(simplex)).iterator(); it.hasNext(); )
{
Simplex s = (Simplex)it.next();
for (Iterator otherIt = simplex.iterator(); otherIt.hasNext(); )
{
var v = otherIt.next();
if (v.Equals(vertex)) continue;
if (!s.contains(v))
{
s = null;
break;
}
}
if (s == null)
continue;
return s;
}
return null;
}
/**
* Place a new point site into the DT.
* @param site the new Pnt
* @return set of all new triangles created
*/
public Set delaunayPlace(Pnt site)
{
Set newTriangles = new HashSet();
Set oldTriangles = new HashSet();
Set doneSet = new HashSet();
LinkedList waitingQ = new LinkedList();
// Locate containing triangle
if (debug)
{
Console.WriteLine("Locate");
}
Simplex triangle = locate(site);
// Give up if no containing triangle or if site is already in DT
var triangle_null = triangle == null;
if (triangle_null || triangle.contains(site))
{
return(newTriangles);
}
// Find Delaunay cavity (those triangles with site in their circumcircles)
if (debug)
{
Console.WriteLine("Cavity");
}
waitingQ.add(triangle);
while (!waitingQ.isEmpty())
{
triangle = (Simplex)waitingQ.removeFirst();
if (site.vsCircumcircle((Pnt[])triangle.toArray(new Pnt[0])) == 1)
{
continue;
}
oldTriangles.add(triangle);
Iterator it = this.neighbors(triangle).iterator();
for (; it.hasNext();)
{
Simplex tri = (Simplex)it.next();
if (doneSet.contains(tri))
{
continue;
}
doneSet.add(tri);
waitingQ.add(tri);
}
}
// Create the new triangles
if (debug)
{
Console.WriteLine("Create");
}
for (Iterator it = Simplex.boundary(oldTriangles).iterator(); it.hasNext();)
{
Set facet = (Set)it.next();
facet.add(site);
newTriangles.add(new Simplex(facet));
}
// Replace old triangles with new triangles
if (debug)
{
Console.WriteLine("Update");
}
this.update(oldTriangles, newTriangles);
// Update mostRecent triangle
if (!newTriangles.isEmpty())
{
mostRecent = (Simplex)newTriangles.iterator().next();
}
return(newTriangles);
}