private IEnumerable <T> EnumerateSphere(ITuple center, double distance, bool tHemisphere)
{
Node[] stack;
int sp;
int i;
Leaf leaf;
double distance2 = distance * distance;
double[] centerValues = new double[dimMax];
for (int dim = dimMax; --dim >= 0;)
{
centerValues[dim] = center.GetDimValue(dim);
}
stack = new Node[StackDepth];
sp = 0;
IElement ele = eleRoot;
while (ele is Node)
{
Node node = (Node)ele;
if (center.GetDimValue(node.dim) - distance <= node.splitValue)
{
if (sp == StackDepth)
{
throw new ApplicationException("Bspt.EnumerateSphere tree stack overflow");
}
stack[sp++] = node;
ele = node.eleLE;
}
else
{
ele = node.eleGE;
}
}
leaf = (Leaf)ele;
i = 0;
while (true)
{
for (; i < leaf.count; ++i)
{
var lt = leaf.tuples[i];
var distT = lt.GetDimValue(0) - centerValues[0];
if (tHemisphere && distT < 0)
{
goto Break_Widthin;
}
double dist2 = distT * distT;
if (dist2 > distance2)
{
goto Break_Widthin;
}
for (int dim = dimMax; --dim > 0;)
{
distT = lt.GetDimValue(dim) - centerValues[dim];
dist2 += distT * distT;
if (dist2 > distance2)
{
goto Break_Widthin;
}
}
var ret = leaf.tuples[i++];
ret.Distance2 = dist2;
yield return(ret);
goto continue_while;
Break_Widthin:
;
}
if (sp == 0)
{
yield break;
}
ele = stack[--sp];
while (ele is Node)
{
Node node = (Node)ele;
if (center.GetDimValue(node.dim) + distance < node.splitValue)
{
if (sp == 0)
{
yield break;
}
ele = stack[--sp];
}
else
{
ele = node.eleGE;
while (ele is Node)
{
Node nodeLeft = (Node)ele;
stack[sp++] = nodeLeft;
ele = nodeLeft.eleLE;
}
}
}
leaf = (Leaf)ele;
i = 0;
continue_while:
;
}
}
public IEnumerable <T> EnumerateNears(ITuple center, double distance)
{
Node[] stack = new Node[StackDepth];
int sp = 0;
IElement ele = eleRoot;
while (ele is Node)
{
Node node = (Node)ele;
if (center.GetDimValue(node.dim) - distance <= node.splitValue)
{
if (sp == StackDepth)
{
throw new ApplicationException("Bspt.EnumerateNear tree stack overflow");
}
stack[sp++] = node;
ele = node.eleLE;
}
else
{
ele = node.eleGE;
}
}
Leaf leaf = (Leaf)ele;
int i = 0;
while (true)
{
if (i < leaf.count)
{
yield return(leaf.tuples[i++]);
continue;
}
if (sp == 0)
{
yield break;
}
ele = stack[--sp];
while (ele is Node)
{
Node node = (Node)ele;
if (center.GetDimValue(node.dim) + distance < node.splitValue)
{
if (sp == 0)
{
yield break;
}
ele = stack[--sp];
}
else
{
ele = node.eleGE;
while (ele is Node)
{
Node nodeLeft = (Node)ele;
stack[sp++] = nodeLeft;
ele = nodeLeft.eleLE;
}
}
}
leaf = (Leaf)ele;
i = 0;
yield return(leaf.tuples[i++]);
}
}
