private void QueryRange(IntervalTreeNode intervalTreeNode, Int64 start, Int64 end, List <T> results)
{
for (int i = intervalTreeNode.first; i <= intervalTreeNode.last; i++)
{
var entry = m_Entries[i];
if (end >= entry.intervalStart && start < entry.intervalEnd)
{
results.Add(entry.item);
}
}
if (intervalTreeNode.center == kCenterUnknown)
{
return;
}
if (intervalTreeNode.left != kInvalidNode && start < intervalTreeNode.center)
{
QueryRange(m_Nodes[intervalTreeNode.left], start, end, results);
}
if (intervalTreeNode.right != kInvalidNode && end > intervalTreeNode.center)
{
QueryRange(m_Nodes[intervalTreeNode.right], start, end, results);
}
}
private void Query(IntervalTreeNode intervalTreeNode, Int64 value, List <T> results)
{
for (int i = intervalTreeNode.first; i <= intervalTreeNode.last; i++)
{
var entry = m_Entries[i];
if (value >= entry.intervalStart && value < entry.intervalEnd)
{
results.Add(entry.item);
}
}
if (intervalTreeNode.center == kCenterUnknown)
{
return;
}
if (intervalTreeNode.left != kInvalidNode && value < intervalTreeNode.center)
{
Query(m_Nodes[intervalTreeNode.left], value, results);
}
if (intervalTreeNode.right != kInvalidNode && value > intervalTreeNode.center)
{
Query(m_Nodes[intervalTreeNode.right], value, results);
}
}
private int Rebuild(int start, int end)
{
IntervalTreeNode intervalTreeNode = new IntervalTreeNode();
// minimum size, don't subdivide
int count = end - start + 1;
if (count < kMinNodeSize)
{
intervalTreeNode = new IntervalTreeNode()
{
center = kCenterUnknown, first = start, last = end, left = kInvalidNode, right = kInvalidNode
};
m_Nodes.Add(intervalTreeNode);
return(m_Nodes.Count - 1);
}
var min = Int64.MaxValue;
var max = Int64.MinValue;
for (int i = start; i <= end; i++)
{
var o = m_Entries[i];
min = Math.Min(min, o.intervalStart);
max = Math.Max(max, o.intervalEnd);
}
var center = (max + min) / 2;
intervalTreeNode.center = center;
// first pass, put every thing left of center, left
int x = start;
int y = end;
while (true)
{
while (x <= end && m_Entries[x].intervalEnd < center)
{
x++;
}
while (y >= start && m_Entries[y].intervalEnd >= center)
{
y--;
}
if (x > y)
{
break;
}
var nodeX = m_Entries[x];
var nodeY = m_Entries[y];
m_Entries[y] = nodeX;
m_Entries[x] = nodeY;
}
intervalTreeNode.first = x;
// second pass, put every start passed the center right
y = end;
while (true)
{
while (x <= end && m_Entries[x].intervalStart <= center)
{
x++;
}
while (y >= start && m_Entries[y].intervalStart > center)
{
y--;
}
if (x > y)
{
break;
}
var nodeX = m_Entries[x];
var nodeY = m_Entries[y];
m_Entries[y] = nodeX;
m_Entries[x] = nodeY;
}
intervalTreeNode.last = y;
// reserve a place
m_Nodes.Add(new IntervalTreeNode());
int index = m_Nodes.Count - 1;
intervalTreeNode.left = kInvalidNode;
intervalTreeNode.right = kInvalidNode;
if (start < intervalTreeNode.first)
{
intervalTreeNode.left = Rebuild(start, intervalTreeNode.first - 1);
}
if (end > intervalTreeNode.last)
{
intervalTreeNode.right = Rebuild(intervalTreeNode.last + 1, end);
}
m_Nodes[index] = intervalTreeNode;
return(index);
}
