/// <summary>
/// Splits the given node in two other nodes.
/// </summary>
/// <param name="node"></param>
/// <param name="minimumSize"></param>
/// <returns></returns>
private static Node[] SplitNode(Node node, int minimumSize)
{
bool leaf = (node.Children is List <T>);
// create the target nodes.
var nodes = new Node[2];
nodes[0] = new Node();
nodes[0].Boxes = new List <BoxF2D>();
if (leaf)
{
nodes[0].Children = new List <T>();
}
else
{
nodes[0].Children = new List <Node>();
}
nodes[1] = new Node();
nodes[1].Boxes = new List <BoxF2D>();
if (leaf)
{
nodes[1].Children = new List <T>();
}
else
{
nodes[1].Children = new List <Node>();
}
// select the seed boxes.
int[] seeds = RTreeMemoryIndex <T> .SelectSeeds(node.Boxes);
// add the boxes.
nodes[0].Boxes.Add(node.Boxes[seeds[0]]);
nodes[1].Boxes.Add(node.Boxes[seeds[1]]);
nodes[0].Children.Add(node.Children[seeds[0]]);
nodes[1].Children.Add(node.Children[seeds[1]]);
// create the boxes.
var boxes = new BoxF2D[2]
{
node.Boxes[seeds[0]], node.Boxes[seeds[1]]
};
node.Boxes.RemoveAt(seeds[0]); // seeds[1] is always < seeds[0].
node.Boxes.RemoveAt(seeds[1]);
node.Children.RemoveAt(seeds[0]);
node.Children.RemoveAt(seeds[1]);
while (node.Boxes.Count > 0)
{
// check if one of them needs em all!
if (nodes[0].Boxes.Count + node.Boxes.Count == minimumSize)
{ // all remaining boxes need te be assigned here.
for (int idx = 0; node.Boxes.Count > 0; idx++)
{
boxes[0] = boxes[0].Union(node.Boxes[0]);
nodes[0].Boxes.Add(node.Boxes[0]);
nodes[0].Children.Add(node.Children[0]);
node.Boxes.RemoveAt(0);
node.Children.RemoveAt(0);
}
}
else if (nodes[1].Boxes.Count + node.Boxes.Count == minimumSize)
{ // all remaining boxes need te be assigned here.
for (int idx = 0; node.Boxes.Count > 0; idx++)
{
boxes[1] = boxes[1].Union(node.Boxes[0]);
nodes[1].Boxes.Add(node.Boxes[0]);
nodes[1].Children.Add(node.Children[0]);
node.Boxes.RemoveAt(0);
node.Children.RemoveAt(0);
}
}
else
{ // choose one of the leaves.
int leafIdx;
int nextId = RTreeMemoryIndex <T> .PickNext(boxes, node.Boxes, out leafIdx);
boxes[leafIdx] = boxes[leafIdx].Union(node.Boxes[nextId]);
nodes[leafIdx].Boxes.Add(node.Boxes[nextId]);
nodes[leafIdx].Children.Add(node.Children[nextId]);
node.Boxes.RemoveAt(nextId);
node.Children.RemoveAt(nextId);
}
}
RTreeMemoryIndex <T> .SetParents(nodes[0]);
RTreeMemoryIndex <T> .SetParents(nodes[1]);
return(nodes);
}
private static RTreeMemoryIndex <T> .Node[] SplitNode(RTreeMemoryIndex <T> .Node node, int minimumSize)
{
int num1 = node.Children is List <T>? 1 : 0;
RTreeMemoryIndex <T> .Node[] nodeArray = new RTreeMemoryIndex <T> .Node[2]
{
new RTreeMemoryIndex <T> .Node(),
null
};
nodeArray[0].Boxes = new List <BoxF2D>();
nodeArray[0].Children = num1 == 0 ? (IList) new List <RTreeMemoryIndex <T> .Node>() : (IList) new List <T>();
nodeArray[1] = new RTreeMemoryIndex <T> .Node();
nodeArray[1].Boxes = new List <BoxF2D>();
nodeArray[1].Children = num1 == 0 ? (IList) new List <RTreeMemoryIndex <T> .Node>() : (IList) new List <T>();
int[] numArray = RTreeMemoryIndex <T> .SelectSeeds(node.Boxes);
nodeArray[0].Boxes.Add(node.Boxes[numArray[0]]);
nodeArray[1].Boxes.Add(node.Boxes[numArray[1]]);
nodeArray[0].Children.Add(node.Children[numArray[0]]);
nodeArray[1].Children.Add(node.Children[numArray[1]]);
BoxF2D[] nodeBoxes = new BoxF2D[2]
{
node.Boxes[numArray[0]],
node.Boxes[numArray[1]]
};
node.Boxes.RemoveAt(numArray[0]);
node.Boxes.RemoveAt(numArray[1]);
node.Children.RemoveAt(numArray[0]);
node.Children.RemoveAt(numArray[1]);
while (node.Boxes.Count > 0)
{
if (nodeArray[0].Boxes.Count + node.Boxes.Count == minimumSize)
{
int num2 = 0;
while (node.Boxes.Count > 0)
{
nodeBoxes[0] = nodeBoxes[0].Union(node.Boxes[0]);
nodeArray[0].Boxes.Add(node.Boxes[0]);
nodeArray[0].Children.Add(node.Children[0]);
node.Boxes.RemoveAt(0);
node.Children.RemoveAt(0);
++num2;
}
}
else if (nodeArray[1].Boxes.Count + node.Boxes.Count == minimumSize)
{
int num2 = 0;
while (node.Boxes.Count > 0)
{
nodeBoxes[1] = nodeBoxes[1].Union(node.Boxes[0]);
nodeArray[1].Boxes.Add(node.Boxes[0]);
nodeArray[1].Children.Add(node.Children[0]);
node.Boxes.RemoveAt(0);
node.Children.RemoveAt(0);
++num2;
}
}
else
{
int nodeBoxIndex;
int index = RTreeMemoryIndex <T> .PickNext(nodeBoxes, (IList <BoxF2D>) node.Boxes, out nodeBoxIndex);
nodeBoxes[nodeBoxIndex] = nodeBoxes[nodeBoxIndex].Union(node.Boxes[index]);
nodeArray[nodeBoxIndex].Boxes.Add(node.Boxes[index]);
nodeArray[nodeBoxIndex].Children.Add(node.Children[index]);
node.Boxes.RemoveAt(index);
node.Children.RemoveAt(index);
}
}
RTreeMemoryIndex <T> .SetParents(nodeArray[0]);
RTreeMemoryIndex <T> .SetParents(nodeArray[1]);
return(nodeArray);
}