cn.jimmiez.pcu.common.graphics

类 Octree

java.lang.Object

cn.jimmiez.pcu.common.graphics.Octree

直接已知子类:

OctreeVoxelizer

public class Octree
extends Object

An octree recursively divide a box 3d space into eight octants and can accelerate the process of searching nearest neighbors of points.

嵌套类概要

嵌套类

限定符和类型	类和说明
class	Octree.OctreeNode The octree node in the 3d space.

字段概要

字段

限定符和类型	字段和说明
protected static int	MAX_DEPTH the max depth of this tree, theoretically it shall be less than 21, because every three bits in a Long-type octree-node index is used to locate its position of siblings.
protected Map<Long,Octree.OctreeNode>	octreeIndices used to find an octree node by its index the index of an octree node is generated according to its spatial position
protected List<javax.vecmath.Point3d>	points
protected Octree.OctreeNode	root the root node of the octree, the size of root node is the bounding box of point cloud

构造器概要

构造器

构造器和说明
Octree()

方法概要

限定符和类型	方法和说明
List<Octree.OctreeNode>	adjacentNodes(Long nodeIndex, Adjacency adjacency) search adjacent nodes of an octree node
void	buildIndex(List<javax.vecmath.Point3d> points) build spatial index for point cloud note that the length double array in List points must be 3
protected void	createOctree(int currentDepth, Octree.OctreeNode currentNode) partition the space recursively
int	getMaxPointsPerNode()
protected Long	locateOctreeNode(Octree.OctreeNode node, javax.vecmath.Point3d point) find the index of octree node in which the target point is located
List<Integer>	searchAllNeighborsWithinDistance(int index, double radius) search all neighboring points of the point with specified index within distance
List<Integer>	searchAllNeighborsWithinDistance(javax.vecmath.Point3d point, double radius) search all neighboring points of specified point within distance
int[]	searchNearestNeighbors(int k, int index) If you want to acquire the k-nearest neighbors of a certain point p, call this function, octree will decrease the time cost
int[]	searchNearestNeighbors(int k, javax.vecmath.Point3d point) search k nearest neighbors for the point
void	setMaxPointsPerNode(int m)

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

字段详细资料

root

protected Octree.OctreeNode root

the root node of the octree, the size of root node is the bounding box of point cloud

points

protected List<javax.vecmath.Point3d> points

octreeIndices

protected Map<Long,Octree.OctreeNode> octreeIndices

used to find an octree node by its index the index of an octree node is generated according to its spatial position

MAX_DEPTH

protected static final int MAX_DEPTH

the max depth of this tree, theoretically it shall be less than 21, because every three bits in a Long-type octree-node index is used to locate its position of siblings.

另请参阅:

常量字段值

构造器详细资料

Octree

public Octree()

方法详细资料

buildIndex

public void buildIndex(List<javax.vecmath.Point3d> points)

build spatial index for point cloud note that the length double array in List points must be 3

参数:

points - the point cloud

searchNearestNeighbors

public int[] searchNearestNeighbors(int k,
                                    int index)

If you want to acquire the k-nearest neighbors of a certain point p, call this function, octree will decrease the time cost

参数:

k - the number of nearest neighbors

index - the index of point p

返回:

the indices of nearest neighbors

searchNearestNeighbors

public int[] searchNearestNeighbors(int k,
                                    javax.vecmath.Point3d point)

search k nearest neighbors for the point

参数:

k - the number of nearest neighbors, 0 <= k < points.size()

point - the point, non-null

返回:

an array of indices of neighboring point, the length is k,

抛出:

IllegalStateException - if previously forget to call buildIndex()

IllegalArgumentException - if size of points is less than k + 1

createOctree

protected void createOctree(int currentDepth,
                            Octree.OctreeNode currentNode)

partition the space recursively

参数:

currentDepth - the depth of current octree node

currentNode - current octree node

locateOctreeNode

protected Long locateOctreeNode(Octree.OctreeNode node,
                                javax.vecmath.Point3d point)

find the index of octree node in which the target point is located

参数:

node - the root octree node

point - the target point

返回:

the index of leaf node

searchAllNeighborsWithinDistance

public List<Integer> searchAllNeighborsWithinDistance(javax.vecmath.Point3d point,
                                                      double radius)

search all neighboring points of specified point within distance

参数:

point - the point

radius - the distance

返回:

a List of indices of neighboring points

searchAllNeighborsWithinDistance

public List<Integer> searchAllNeighborsWithinDistance(int index,
                                                      double radius)

search all neighboring points of the point with specified index within distance

参数:

index - the index of a point

radius - radius of neighborhood

返回:

indices of neighboring points of this point

adjacentNodes

public List<Octree.OctreeNode> adjacentNodes(Long nodeIndex,
                                             Adjacency adjacency)

search adjacent nodes of an octree node

参数:

nodeIndex - the index of octree node

adjacency - see Adjacency

返回:

the list of adjacent octree nodes

getMaxPointsPerNode

public int getMaxPointsPerNode()

setMaxPointsPerNode

public void setMaxPointsPerNode(int m)