Avogadro::Core::NeighborPerceiver#

class NeighborPerceiver#

This class can be used to find physically neighboring points in linear average time.

Public Functions

NeighborPerceiver(const Array<Vector3> points, float maxDistance)#

Creates a NeighborPerceiver that detects neighbors up to at least some distance.

The bin size always equals maxDistance. Only occupied bins are stored, so memory is proportional to the number of points however widely they are spread. Points with non-finite coordinates are ignored: they are never returned as neighbors, and do not affect the other points.

Parameters:

points – Positions in 3D space to detect neighbors among.
maxDistance – All neighbors strictly within this distance will be detected. Should be as low as possible for best performance.

Array<Index> getNeighborsInclusive(const Vector3 &point) const#

Returns a list of neighboring points. Linear time to number of neighbors. Can include some neighbors up to 2*sqrt(3) times the bin size, which always equals the maximum distance. A non-finite query point has no neighbors. The list is newly allocated on every call; if performance/fragmentation is a concern, prefer NeighborPerceiver::getNeighborsInclusiveInPlace().

Parameters:: point – Position to return neighbors of, can be located anywhere.

void getNeighborsInclusiveInPlace(Array<Index> &out, const Vector3 &point) const#

Fills an array with all neighboring points. Linear time to number of neighbors. Can include some neighbors up to 2*sqrt(3) times the bin size, which always equals the maximum distance. A non-finite query point has no neighbors.

Parameters:

out – Array to output neighbor indices in.
point – Position to return neighbors of, can be located anywhere.

Protected Attributes

float m_maxDistance#

double m_binSize#: Edge length of the cubic bins. Always equal to m_maxDistance.

std::unordered_map<BinKey, std::vector<Index>, BinKeyHash> m_bins#: Only occupied bins are stored (sparse), in insertion order per bin.

Vector3 m_anchor = Vector3::Zero()#: Origin of the bin grid: the bounding box minimum of the finite points, or the origin if the extent is too large for a minimum-anchored grid.

Vector3 m_minPos = Vector3::Zero()#

Vector3 m_maxPos = Vector3::Zero()#