public static int calculateGamma(Point u, Point v, Graph currFacets, int[] gi, int[] facetDiameter)
{
int shortestPath = ShortestPath.BFS(currFacets, u, v);
if (shortestPath < 0)
{
shortestPath = Globals.maxDiameter[Globals.k] + Globals.k - Globals.gap;
}
return(Globals.maxDiameter[Globals.k] + Globals.k - Globals.gap - Math.Min(shortestPath, calculateDDot(u, v, currFacets, facetDiameter)));
}
private static List <Graph> shellHelper(Graph currFacets, List <Point> vertexSet, List <Point> nonVertexSet, List <Point> coreSet, bool[] facetsUsed, Point u, Point v, int[] facetDiameter)
{
List <Graph> result = new List <Graph>();
int sp;
bool uRedundant, vRedundant; //track if either u or v is redundant. For message output.
bool[] _facetsUsed = new bool[facetsUsed.Length];
List <Point> _nonVertexSet = new List <Point>(), _corePointSet = new List <Point>(), _vertexSet = new List <Point>();
//creating copies of reference data
for (int i = 0; i < facetsUsed.Length; i++)
{
_facetsUsed[i] = facetsUsed[i];
}
foreach (Point p in nonVertexSet)
{
_nonVertexSet.Add(p.clone());
}
foreach (Point p in coreSet)
{
_corePointSet.Add(p.clone());
}
foreach (Point p in vertexSet)
{
_vertexSet.Add(p.clone());
}
//calculates gi values
int[] gi = updateGi(currFacets, u, v);
//calculates next facet to add
int nextFacet = calculateNextFacet(u, v, currFacets, facetsUsed, gi);
List <Point> facetPoints = currFacets.getAllContainedPoints(nextFacet);
List <Point> dMinus1FacetPoints = new List <Point>();
foreach (Point p in facetPoints)
{
if (Convert.ToInt32(p.Coordinates[nextFacet / 2].ToString()) == ((nextFacet % 2 == 0) ? 0 : Globals.k))
{
dMinus1FacetPoints.Add(p.decreaseDimensionality(nextFacet / 2));
}
}
//generate all valid d-1 polytopes that can be considered as a facet.
List <Graph> possibleFacets = Generate.dMinus1Polytopes(dMinus1FacetPoints, gi[nextFacet]);
_facetsUsed[nextFacet] = true;
if (possibleFacets != null && possibleFacets.Count > 0)
{
if (Globals.messageOn)
{
Console.WriteLine("Number of possible facets: " + possibleFacets.Count);
}
//try every possible facet as a shell
foreach (Graph f in possibleFacets)
{
//todo -- test if .clone() is actually required
Graph temp = currFacets.clone();
Graph h = f.clone();
//set values for current selected facet to shell
facetDiameter[nextFacet] = f.Points.Count / 2;
//increase dimensionality of facet
h.addDimensionality(nextFacet / 2, (nextFacet % 2 == 0) ? true : false);
//add facet to gamma
temp.AddFacet(h);
//check 1 - looks for sp from u to v
sp = ShortestPath.BFS(temp, u, v);
if (sp >= 0 && sp < Globals.maxDiameter[Globals.k] + Globals.k - Globals.gap)
{
if (Globals.messageOn)
{
Console.WriteLine("SP < " + Globals.maxLength);
}
continue;
}
//check 2 - gamma check
int gamma = calculateGamma(u, v, temp, gi, facetDiameter);
if (gamma > 0)
{
if (Globals.messageOn)
{
Console.WriteLine("Gamma > 0.");
}
continue;
}
//check 3 - convex core check -- u and v must be vertices of the convex hull generated by the current subgraph.
if (!checkCore(u, v, gi, temp.getAllContainedPoints(), out uRedundant, out vRedundant))
{
if (Globals.messageOn)
{
Console.WriteLine("Convex Core Check. {0}", ((uRedundant && vRedundant) ? "u and v are not vertices." : (uRedundant ? "u is not a vertex." : "v is not a vertex.")));
}
continue;
}
//if shelling is incomplete
if (checkUnshelledFacet(_facetsUsed))
{
result.AddRange(shellHelper(temp, _vertexSet, _nonVertexSet, _corePointSet, _facetsUsed, u, v, facetDiameter));
}
else
{
if (!CDD.compareAlToPoints(temp.Points)) //convex hull call
{
continue;
}
totalShelling++;
if (Globals.messageOn)
{
Console.WriteLine("***** FULL SHELLING FOUND *****");
Console.WriteLine(temp);
}
result.Add(temp);
}
}
facetDiameter[nextFacet] = Globals.maxDiameter[Globals.k];
if (Globals.messageOn)
{
Console.WriteLine("All facets checked.");
}
return(result);
}
else
{
if (Globals.messageOn)
{
Console.WriteLine("No possible facets.");
}
return(new List <Graph>());
}
}
public static int calculateDistanceToFacet(Point u, Graph currFacets, int facet)
{
return(Math.Min(ShortestPath.BFStoFacet(currFacets, u, facet), ShortestPath.BFStoFacetEstimator(currFacets, u, facet)));
}