private OctreeBox(List <Point> pts, OctreeBox parent,
int remainingNotLeafLayers, int positionInParent)
{
// I'm even more proud about this boundary finder :)
for (int i = 2; i >= 0; i--)
{
int n = (int)System.Math.Pow(2, i);
if (positionInParent >= n)
{
_dimensionsMax[i] = parent._dimensionsMax[i];
_dimensionsMin[i] = parent.Mean(i);
positionInParent -= n;
}
else
{
_dimensionsMax[i] = parent.Mean(i);
_dimensionsMin[i] = parent._dimensionsMin[i];
}
}
if (remainingNotLeafLayers == 0)
{
this.IsLeaf = true;
this.SubBoxes = null;
this.Points = pts;
}
else
{
// All points in pts MUST lie within this box!
Subdivide(pts, remainingNotLeafLayers - 1);
}
}
//DOKU
private List <OctreeBox> BoxesInRange(Point query, double squareRange,
OctreeBox node)
{
List <OctreeBox> fittingSubBoxes = new List <OctreeBox>();
if (node.IsLeaf)
{
fittingSubBoxes.Add(node);
}
else
{
foreach (OctreeBox box in node.SubBoxes)
{
// skip nodes that are too far away
if (box.MinimumSquareDistanceTo(query) > squareRange)
{
continue;
}
if (box.IsLeaf)
{
fittingSubBoxes.Add(box);
}
else
{
fittingSubBoxes.AddRange(
BoxesInRange(query, squareRange, box));
}
}
}
return(fittingSubBoxes);
}
//DOKU
private void TraverseSearch(Point query,
OctreeBox node, NeigbourCollector neighbours)
{
if (node.IsLeaf)
{
foreach (Point p in node.Points)
{
neighbours.AddNeighbour(p);
}
return;
}
// not leaf
foreach (OctreeBox subNode in node.SubBoxes)
{
double curMinSDist = subNode.MinimumSquareDistanceTo(query);
//TODO that shit about the Neighbourlist count
// is really, really crappy!
if (neighbours.BestNeighbours.Count > 0 &&
curMinSDist > neighbours.LargestSquareDistance)
{
continue;
}
TraverseSearch(query, subNode, neighbours);
}
return;
}
//DOKU
public List <OctreeBox> GetLeafs(OctreeBox parent)
{
List <OctreeBox> leafs = new List <OctreeBox>();
if (parent.IsLeaf)
{
leafs.Add(parent);
return(leafs);
}
foreach (OctreeBox child in parent.SubBoxes)
{
leafs.AddRange(GetLeafs(child));
}
return(leafs);
}
//DOKU
private OctreeBox[] Subdivide(List <Point> pts, int remainingNoLeafLayers)
{
this.SubBoxes = new OctreeBox[8];
List <Point>[] subdividedPointCloud = new List <Point> [8];
// initialize array
for (int i = 0; i < 8; i++)
{
subdividedPointCloud[i] = new List <Point>();
}
foreach (Point p in pts)
{
// I'm proud of this simple method of assigning the point :-)
int boxNumber = 0;
if (p.Z > Zmean)
{
boxNumber += 4;
}
if (p.Y > Ymean)
{
boxNumber += 2;
}
if (p.X > Xmean)
{
boxNumber += 1;
}
subdividedPointCloud[boxNumber].Add(p);
}
// write divided points to subboxes
for (int i = 0; i < 8; i++)
{
SubBoxes[i] =
new OctreeBox(subdividedPointCloud[i], this, remainingNoLeafLayers, i);
}
// reset Points to null, for all points are now Points of the SubBoxes
this.Points = null;
this.IsLeaf = false;
return(this.SubBoxes);
}
//DOKU
public Octree(Point[] pts, int nonLeafLayers, int maxPointsPerBox)
{
if (maxPointsPerBox == 0)
{
throw new ArgumentException(
"An octree with the maximul leaf size 0 is impossible!");
}
_rootNode = new OctreeBox(pts.ToList(), nonLeafLayers);
// If there is no point cap, the tree is done here.
if (maxPointsPerBox < 0)
{
return;
}
// Get all the leafs to decide if a subdivision is
// necessary or not
List <OctreeBox> leafs = GetLeafs(_rootNode);
// Divide all leafs into smaller boxes.
// If a box has too many points, add it to
// the list of boxes that shall be divided.
int i = 0;
while (i < leafs.Count)
{
OctreeBox box = leafs[i];
if (box.Points.Count <= maxPointsPerBox)
{
i++;
continue;
}
leafs.RemoveAt(i);
leafs.AddRange(box.Subdivide());
}
}
