public void subtract(Shape s)
{
int area = this.set.Count;
Point? center = s.getCenter();
int cx = center.Value.X;
int cy = center.Value.Y;
foreach (Point? p in s.set)
{
this.set.Remove(p);
}
this.sumX -= area * cx;
this.sumY -= area * cy;
// BIG WARNING! Margin points and coords are not moved back.
}
/**
* Extracts a horizontal or vertical shape of the original Shape.
* The area of the new, smaller flat shape will be smaller thatn the areaLimit.
* sizeLimit specifies the width of the flat, extracted shape.
*/
public static Shape reduceShapeHVAreaLimit(Shape originalShape, Point? firstPoint, int sizeLimit, bool horizontal, int areaLimit)
{
int px, py, nx, ny;
int[] neighx = { -1, 0, 1, -1, 1, -1, 0, 1 }, neighy = { -1, -1, 1, 0, 0, 1, 1, 1 };
Shape reducedShape = new Shape();
Queue<Point?> queue = new Queue<Point?>();
if (originalShape == null)
{
return null;
}
if (!originalShape.contains(firstPoint))
{
return null;
}
queue.Enqueue(firstPoint);
while (true)
{
Point? head = queue.Dequeue();
reducedShape.Add(head);
int reducedArea = reducedShape.Area;
Point? shapeCenter = reducedShape.getCenter();
px = head.Value.X;
py = head.Value.Y;
for (int i = 0; i < 8; i++)
{
nx = px + neighx[i];
ny = py + neighy[i];
Point? neighbour = new Point(nx, ny);
if ((originalShape.contains(neighbour))
&& (!reducedShape.contains(neighbour)) && (!queue.Contains(neighbour))
&& (queue.Count() + reducedArea < areaLimit)
&& (((horizontal) && (Math.Abs(nx - shapeCenter.Value.X) < sizeLimit))
|| ((!horizontal) && (Math.Abs(ny - shapeCenter.Value.Y) < sizeLimit)))
)
{
queue.Enqueue(neighbour);
}
}
if ((reducedArea > areaLimit) || (queue.Count == 0))
{
break;
}
}
return reducedShape;
}
