protected QuadNode <T> SearchColumn(QuadNode <T> root, QuadNode <T> node)
{
if (root == null)
{
return(null);
}
if (root == node)
{
return(root);
}
else
{
return(SearchColumn(root.Bottom, node));
}
}
public bool AddNodeToBottom(QuadNode <T> node, int column)
{
int newNodeHeight = GetColumnHeight(column);
//add node to node above
if (newNodeHeight != 0)
{
QuadNode <T> aboveNode = GetTheMostBottomNode(column);
if (aboveNode != null)
{
aboveNode.Bottom = node;
node.Top = aboveNode;
}
}
else
{
_columnsRoots[column] = node;
}
//add node to left column
if (column > 0)
{
QuadNode <T> leftNode = SearchColumn(_columnsRoots[column - 1], newNodeHeight);
if (leftNode != null)
{
leftNode.Right = node;
node.Left = leftNode;
}
}
//add node to right column
if (column < NumberOfColumns - 1)
{
QuadNode <T> rightNode = SearchColumn(_columnsRoots[column + 1], newNodeHeight);
if (rightNode != null)
{
rightNode.Left = node;
node.Right = rightNode;
}
}
return(true);
}
public Neighbours IsAdjacentToNode(QuadNode <T> node)
{
if (Top != null && Top == node)
{
return(Neighbours.Top);
}
if (Left != null && Left == node)
{
return(Neighbours.Left);
}
if (Bottom != null && Bottom == node)
{
return(Neighbours.Bottom);
}
if (Right != null && Right == node)
{
return(Neighbours.Right);
}
return(Neighbours.None);
}
/// <summary>
/// Switchs the position of the node with a neighbouring node. Has in consideration the references of the neigbour node neighbours.
/// </summary>
/// <param name="neighbour">The relative position of the node we want to switch places with.</param>
/// <returns>Returns <see langword="false"/> if the neigbour node is null.</returns>
public bool SwitchNodePosition(Neighbours neighbour)
{
switch (neighbour)
{
case Neighbours.Top:
if (Top == null)
{
return(false);
}
QuadNode <T> temporary = Top.MemberwiseClone() as QuadNode <T>;
QuadNode <T> substitute = Top;
////assign nodes to the neigbour nodes of the involved pieces
if (substitute.Left != null)
{
substitute.Left.Right = this;
}
if (substitute.Right != null)
{
substitute.Right.Left = this;
}
if (substitute.Top != null)
{
substitute.Top.Bottom = this;
}
if (this.Left != null)
{
this.Left.Right = substitute;
}
if (this.Bottom != null)
{
this.Bottom.Top = substitute;
}
if (this.Right != null)
{
this.Right.Left = substitute;
}
////---------------------------------------
////assign nodes of the involved pieces
substitute.Left = this.Left;
substitute.Top = this;
substitute.Bottom = this.Bottom;
substitute.Right = this.Right;
this.Top = temporary.Top;
this.Left = temporary.Left;
this.Right = temporary.Right;
this.Bottom = substitute;
return(true);
case Neighbours.Left:
if (this.Left == null)
{
return(false);
}
temporary = this.Left.MemberwiseClone() as QuadNode <T>;
substitute = this.Left;
//deal with neigbors of the involved pieces
if (substitute.Left != null)
{
substitute.Left.Right = this;
}
if (substitute.Top != null)
{
substitute.Top.Bottom = this;
}
if (substitute.Bottom != null)
{
substitute.Bottom.Top = this;
}
if (this.Top != null)
{
this.Top.Bottom = substitute;
}
if (this.Right != null)
{
this.Right.Left = substitute;
}
if (this.Bottom != null)
{
this.Bottom.Top = substitute;
}
//assign end nodes of the involved pieces
substitute.Left = this;
substitute.Top = this.Top;
substitute.Bottom = this.Bottom;
substitute.Right = this.Right;
this.Top = temporary.Top;
this.Left = temporary.Left;
this.Bottom = temporary.Bottom;
this.Right = substitute;
return(true);
case Neighbours.Bottom:
if (this.Bottom == null)
{
return(false);
}
temporary = this.Bottom.MemberwiseClone() as QuadNode <T>;
substitute = this.Bottom;
//deal with neigbors of the involved pieces
if (substitute.Left != null)
{
substitute.Left.Right = this;
}
if (substitute.Bottom != null)
{
substitute.Bottom.Top = this;
}
if (substitute.Right != null)
{
substitute.Right.Left = this;
}
if (this.Top != null)
{
this.Top.Bottom = substitute;
}
if (this.Left != null)
{
this.Left.Right = substitute;
}
if (this.Right != null)
{
this.Right.Left = substitute;
}
//assing end nodes of the involved pieces
this.Bottom.Bottom = this;
substitute.Left = this.Left;
substitute.Top = this.Top;
substitute.Right = this.Right;
this.Top = substitute;
this.Left = temporary.Left;
this.Bottom = temporary.Bottom;
this.Right = temporary.Right;
return(true);
case Neighbours.Right:
if (this.Right == null)
{
return(false);
}
temporary = this.Right.MemberwiseClone() as QuadNode <T>;
substitute = this.Right;
//assign end nodes of the neighbour nodes of the involved pieces
if (substitute.Top != null)
{
substitute.Top.Bottom = this;
}
if (substitute.Right != null)
{
substitute.Right.Left = this;
}
if (substitute.Bottom != null)
{
substitute.Bottom.Top = this;
}
if (this.Top != null)
{
this.Top.Bottom = substitute;
}
if (this.Left != null)
{
this.Left.Right = substitute;
}
if (this.Bottom != null)
{
this.Bottom.Top = substitute;
}
//assign end nodes of the involved pieces
substitute.Right = this;
substitute.Left = this.Left;
substitute.Bottom = this.Bottom;
substitute.Top = this.Top;
this.Top = temporary.Top;
this.Left = substitute;
this.Bottom = temporary.Bottom;
this.Right = temporary.Right;
return(true);
default:
break;
}
return(false);
}
/// <summary>
/// Recursive function that looks for a path from a root node to an endNode passing through objects of the same type.
/// </summary>
/// <param name="root"></param>
/// <param name="endNode"></param>
/// <param name="history"> We add a List to dont repeat nodes.</param>
/// <returns>Returns true if a path exists.</returns>
public bool CanConnectThroughType(QuadNode <T> root, QuadNode <T> endNode, List <QuadNode <T> > history)
{
//nulll checks
if (root.TypeID != endNode.TypeID)
{
return(false);
}
//add this node to the history list.
history.Add(root);
//enters the if statement if the root.Top is not null and we never checked the root.Top node
//Is the same for the rest of the nodes (Left, Bottom, Right).
if (root.Top != null && !history.Contains(root.Top))
{
if (root.Top == endNode)
{
return(true);
}
if (CanConnectThroughType(root.Top, endNode, history))
{
return(true);
}
}
if (root.Left != null && !history.Contains(root.Left))
{
if (root.Left == endNode)
{
return(true);
}
if (CanConnectThroughType(root.Left, endNode, history))
{
return(true);
}
}
if (root.Bottom != null && !history.Contains(root.Bottom))
{
if (root.Bottom == endNode)
{
return(true);
}
if (CanConnectThroughType(root.Bottom, endNode, history))
{
return(true);
}
}
if (root.Right != null && !history.Contains(root.Right))
{
if (root.Right == endNode)
{
return(true);
}
if (CanConnectThroughType(root.Right, endNode, history))
{
return(true);
}
}
return(false);
}
public QuadNode <T> GetNode(QuadNode <T> node, int column)
{
return(SearchColumn(_columnsRoots[column], node));
}