public void AddNode(NodeBase node)
{
Quadrant quad = GetQuadrant(node.Position);
node.CurrentQuadrant = quad;
quad.AddNode(node);
}
public QuadTree()
{
// create the quadrants
Quadrants = new Quadrant[Width, Height];
for (int x = 0; x < Width; x++)
{
for (int y = 0; y < Height; y++)
{
Rect r = new Rect(x * quadrantLength, y * quadrantLength, quadrantLength, quadrantLength);
Quadrants[x, y] = new Quadrant(x, y, r);
}
}
// set the neigbours
for (int x = 0; x < Width; x++)
{
for (int y = 0; y < Height; y++)
{
Quadrant quad = Quadrants[x, y];
quad.north = TryGetQuadrant(x, y - 1);
quad.northEast = TryGetQuadrant(x + 1, y - 1);
quad.east = TryGetQuadrant(x + 1, y);
quad.southEast = TryGetQuadrant(x + 1, y + 1);
quad.south = TryGetQuadrant(x, y + 1);
quad.southWest = TryGetQuadrant(x - 1, y + 1);
quad.west = TryGetQuadrant(x - 1, y);
quad.northWest = TryGetQuadrant(x - 1, y - 1);
}
}
}
public void Clear()
{
for (int x = 0; x < Width; x++)
{
for (int y = 0; y < Height; y++)
{
Quadrant q = Quadrants[x, y];
q.Clear();
}
}
}
public void UpdateNodeQuadrant(NodeBase node)
{
Quadrant quad = GetQuadrant(node.Position);
if (quad != node.CurrentQuadrant)
{
node.CurrentQuadrant.RemoveNode(node);
node.CurrentQuadrant = quad;
quad.AddNode(node);
}
}
/// <summary>
/// Enumerates all quadrants
/// </summary>
public IEnumerable <Quadrant> AllQuadrants()
{
for (int x = 0; x < Width; x++)
{
for (int y = 0; y < Height; y++)
{
Quadrant q = Quadrants[x, y];
yield return(q);
}
}
}
/// <summary>
/// Efficiently gets all the nodes in a given rectangle
/// </summary>
public IEnumerable <NodeBase> GetNodesInRect(Rect rectangle)
{
Quadrant topLeftQuad = GetQuadrant(rectangle.TopLeft);
Quadrant bottomRightQuad = GetQuadrant(rectangle.BottomRight);
for (int x = topLeftQuad.X; x <= bottomRightQuad.X; x++)
{
for (int y = topLeftQuad.Y; y <= bottomRightQuad.Y; y++)
{
Quadrant q = Quadrants[x, y];
foreach (NodeBase n in q.Nodes)
{
if (rectangle.Contains(n.Position))
{
yield return(n);
}
}
}
}
}
