public static Shape reduceShapeToAreaAndRatio(Shape originalShape, Point? firstPoint, double ratioLimit, int areaLowerLimit, int areaHigherLimit)
{
int[] neighx = { -1, 0, 1, -1, 1, -1, 0, 1 };
int[] neighy = { -1, -1, 1, 0, 0, 1, 1, 1 };
if (ratioLimit <= 0)
{
return null;
}
double ratioLimitInv = 1 / ratioLimit;
int px = 0, py = 0, nx, ny;
Point? head, neighbour;
Shape reducedShape = new Shape();
int reducedArea = 0;
double reducedRatio = 1.0;
Queue<Point?> queue = new Queue<Point?>();
if (originalShape == null)
{
return null;
}
if (!originalShape.contains(firstPoint))
{
return null;
}
queue.Enqueue(firstPoint);
while (true)
{
head = queue.Dequeue();
reducedShape.Add(head);
reducedRatio = reducedShape.getAspectRatio();
reducedArea = reducedShape.Set.Count;
py = head.Value.Y;
for (int i = 0; i < 8; i++)
{
nx = px + neighx[i];
ny = py + neighy[i];
neighbour = new Point(nx, ny);
if ((originalShape.contains(neighbour))
&& (!reducedShape.contains(neighbour)) && (!queue.Contains(neighbour))
&& (reducedArea + queue.Count < areaHigherLimit))
{
queue.Enqueue(neighbour);
}
}
/*
* Stop condition. It's weird but it's faster
*/
if (!(queue.Count > 0))
{
break;
}
else
{
if (reducedArea < areaLowerLimit)
{
continue;
}
else if (reducedArea > areaHigherLimit)
{
break;
}
else
{
if ((ratioLimitInv < reducedRatio) && (reducedRatio < ratioLimit))
{
continue;
}
else
{
break;
}
}
}
}
if ((reducedShape.Set.Count < areaLowerLimit) || ((ratioLimitInv < reducedRatio) && (reducedRatio < ratioLimit)))
{
return null;
}
return reducedShape;
}
