// Recursively build a tree by separating points at plane boundaries.
static KdTree MakeFromPointsInner(
int depth,
int stIndex, int enIndex,
Vector3[] points,
int[] inds,
int dimensions,
KdTree tree)
{
KdTree root = tree != null ? tree : new KdTree(dimensions);
root.enabled = true;
if (depth == 0 && root.rootPoints != points)
{
root.rootPoints = points;
root.rootIndices = inds;
}
root.axis = depth % root.numDims;
int splitPoint = FindPivotIndex(points, inds, stIndex, enIndex, root.axis);
root.pivotIndex = inds[splitPoint];
root.pivot = points[root.pivotIndex];
int leftEndIndex = splitPoint - 1;
if (leftEndIndex >= stIndex)
{
root.lr[0] = MakeFromPointsInner(depth + 1, stIndex, leftEndIndex, points, inds, dimensions, root.lr[0]);
}
else if (root.lr[0] != null)
{
root.lr[0].enabled = false;
}
int rightStartIndex = splitPoint + 1;
if (rightStartIndex <= enIndex)
{
root.lr[1] = MakeFromPointsInner(depth + 1, rightStartIndex, enIndex, points, inds, dimensions, root.lr[1]);
}
else if (root.lr[1] != null)
{
root.lr[1].enabled = false;
}
return(root);
}
/// <summary>
/// Rebalance the tree.
/// </summary>
public static void Rebalance(KdTree root)
{
Regenerate(root, root.numDims, root.rootPoints);
}