//Build Convex Hull using Graham Scan
private static Stack <Point> Build(List <Point> arr)
{
Point firstPoint = new Point(arr[0].X, arr[0].Y);
Stack <Point> hullStack = new Stack <Point>();
hullStack.Push(arr[0]);
hullStack.Push(arr[1]);
Point top = arr[1];
Point nextToTop = arr[0];
for (int i = 2; i < arr.Count; i++)
{
while ((ActionsWithVectors.VectorProduct(ActionsWithVectors.SubtractOf(arr[i], nextToTop),
ActionsWithVectors.SubtractOf(top, nextToTop)) <= 0) && (!Equals(top, firstPoint)))
{
top = nextToTop;
hullStack.Pop();
hullStack.Pop();
if (Equals(top, firstPoint))
{
nextToTop = top;
}
else
{
nextToTop = hullStack.Peek();
}
hullStack.Push(top);
}
hullStack.Push(arr[i]);
nextToTop = top;
top = arr[i];
}
return(hullStack);
}
public int Compare(Point v1, Point v2)
{
int result = 1;
if ((ActionsWithVectors.VectorProduct(ActionsWithVectors.SubtractOf(v1, FirstPoint), ActionsWithVectors.SubtractOf(v2, FirstPoint)) < 0) ||
(ActionsWithVectors.VectorProduct(ActionsWithVectors.SubtractOf(v1, FirstPoint), ActionsWithVectors.SubtractOf(v2, FirstPoint)) == 0) &&
(ActionsWithVectors.Distance(v1, FirstPoint) < ActionsWithVectors.Distance(v2, FirstPoint)))
{
result = -1;
}
if ((v1.X == v2.X) && (v1.Y == v2.Y))
{
result = 0;
}
return(result);
}
public static bool[,] GetFieldFilling(int rows, int columns, List <Point> Minutiae)
{
bool[,] Field = new bool[rows, columns];
List <Point> Hull = ConvexHull.GetConvexHull(Minutiae);
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < columns; j++)
{
Point CurPoint = new Point(i, j);
bool GoodPoint = true;
for (int k = Hull.Count - 1; (k > 0) && GoodPoint; k--)
{
if (ActionsWithVectors.VectorProduct(ActionsWithVectors.SubtractOf(Hull[k - 1], Hull[k]),
ActionsWithVectors.SubtractOf(CurPoint, Hull[k])) > 0)
{
GoodPoint = false;
}
}
if (GoodPoint)
{
if (ActionsWithVectors.VectorProduct(ActionsWithVectors.SubtractOf(Hull[Hull.Count - 1], Hull[0]),
ActionsWithVectors.SubtractOf(CurPoint, Hull[0])) > 0)
{
GoodPoint = false;
}
}
if (GoodPoint)
{
Field[i, j] = true;
}
else
{
Field[i, j] = false;
}
}
}
return(Field);
}
