#include <PointHashGrid3.h>

Public Member Functions
	TPointHashGrid3 (RealType CellSize, PointDataType InvalidValue)

void	Reserve (int32 Num)

void	Reset (RealType NewCellSize)

PointDataType	GetInvalidValue () const

void	InsertPoint (const PointDataType &Value, const TVector< RealType > &Position)

void	InsertPointUnsafe (const PointDataType &Value, const TVector< RealType > &Position)

bool	RemovePoint (const PointDataType &Value, const TVector< RealType > &Position)

bool	RemovePointUnsafe (const PointDataType &Value, const TVector< RealType > &Position)

bool	IsCellEmpty (const TVector< RealType > &Position)

bool	IsCellEmptyUnsafe (const TVector< RealType > &Position)

void	UpdatePoint (const PointDataType &Value, const TVector< RealType > &OldPosition, const TVector< RealType > &NewPosition)

void	UpdatePointUnsafe (const PointDataType &Value, const TVector< RealType > &OldPosition, const TVector< RealType > &NewPosition)

TPair< PointDataType, RealType >	FindNearestInRadius (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc, TFunctionRef< bool(const PointDataType &)> IgnoreFunc) const

TPair< PointDataType, RealType >	FindNearestInRadius (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc) const

TPair< PointDataType, RealType >	FindAnyInRadius (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc, TFunctionRef< bool(const PointDataType &)> IgnoreFunc) const

TPair< PointDataType, RealType >	FindAnyInRadius (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc) const

int	FindPointsInBall (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc, TArray< PointDataType > &ResultsOut, TFunctionRef< bool(const PointDataType &)> IgnoreFunc=[](const PointDataType &data) { return false;}) const

void	EnumeratePointsInBall (const TVector< RealType > &QueryPoint, RealType Radius, TFunctionRef< RealType(const PointDataType &)> DistanceSqFunc, TFunctionRef< bool(PointDataType, double)> ProcessPointFunc, TFunctionRef< bool(const PointDataType &)> IgnoreFunc=[](const PointDataType &data) { return false;}) const

Detailed Description

template<typename PointDataType, typename RealType>
class UE::Geometry::TPointHashGrid3< PointDataType, RealType >

Hash Grid for values associated with 3D points.

This class addresses the situation where you have a list of (point, point_data) and you would like to be able to do efficient proximity queries, i.e. find the nearest point_data for a given query point.

We don't store copies of the 3D points. You provide a point_data type. This could just be the integer index into your list for example, a pointer to something more complex, etc. Insert and Remove functions require you to pass in the 3D point for the point_data. To Update a point you need to know its old and new 3D coordinates.

Constructor & Destructor Documentation

◆ TPointHashGrid3()

template<typename PointDataType , typename RealType >

UE::Geometry::TPointHashGrid3< PointDataType, RealType >::TPointHashGrid3	(	RealType	CellSize,
		PointDataType	InvalidValue
	)

inline

Construct 3D hash grid

Parameters

CellSize	size of grid cells. Clamped to at least a small tolerance size.
InvalidValue	this value will be returned by queries if no valid result is found (e.g. bounded-distance query)

Member Function Documentation

◆ EnumeratePointsInBall()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::EnumeratePointsInBall	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc,
		TFunctionRef< bool(PointDataType, double)>	ProcessPointFunc,
		TFunctionRef< bool(const PointDataType &)>	IgnoreFunc = `[](const PointDataType& data) { return false; }`
	)		const

inline

Call ProcessPointFunc on all points in grid within a given sphere, or until the function returns false Note: Not thread-safe to update, remove or insert points during enumeration.

Parameters

QueryPoint	the center of the query sphere
Radius	the radius of the query sphere
DistanceSqFunc	Function you provide which measures the squared distance between QueryPoint and a Value
ProcessPointFunc	Function you provide to process each found point. Takes point data and the distance squared; returns true to continue iteration, or false to stop.
IgnoreFunc	optional Function you may provide which will result in a Value being ignored if IgnoreFunc(Value) returns true

◆ FindAnyInRadius() [1/2]

template<typename PointDataType , typename RealType >

TPair< PointDataType, RealType > UE::Geometry::TPointHashGrid3< PointDataType, RealType >::FindAnyInRadius	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc
	)		const

inline

◆ FindAnyInRadius() [2/2]

template<typename PointDataType , typename RealType >

TPair< PointDataType, RealType > UE::Geometry::TPointHashGrid3< PointDataType, RealType >::FindAnyInRadius	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc,
		TFunctionRef< bool(const PointDataType &)>	IgnoreFunc
	)		const

inline

Find any point within radius. Note: Not thread-safe to update, remove or insert points during this query.

Parameters

QueryPoint	the center of the query sphere
Radius	the radius of the query sphere
DistanceSqFunc	Function you provide which measures the squared distance between QueryPoint and a Value
IgnoreFunc	optional Function you may provide which will result in a Value being ignored if IgnoreFunc(Value) returns true

Returns: the found pair (Value,DistanceSqFunc(Value)), or (InvalidValue,MaxDouble) if not found

◆ FindNearestInRadius() [1/2]

template<typename PointDataType , typename RealType >

TPair< PointDataType, RealType > UE::Geometry::TPointHashGrid3< PointDataType, RealType >::FindNearestInRadius	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc
	)		const

inline

◆ FindNearestInRadius() [2/2]

template<typename PointDataType , typename RealType >

TPair< PointDataType, RealType > UE::Geometry::TPointHashGrid3< PointDataType, RealType >::FindNearestInRadius	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc,
		TFunctionRef< bool(const PointDataType &)>	IgnoreFunc
	)		const

inline

Find nearest point within radius. Note: Not thread-safe to update, remove or insert points during this query.

Parameters

QueryPoint	the center of the query sphere
Radius	the radius of the query sphere
DistanceSqFunc	Function you provide which measures the squared distance between QueryPoint and a Value
IgnoreFunc	optional Function you may provide which will result in a Value being ignored if IgnoreFunc(Value) returns true

Returns: the found pair (Value,DistanceSqFunc(Value)), or (InvalidValue,MaxDouble) if not found

◆ FindPointsInBall()

template<typename PointDataType , typename RealType >

int UE::Geometry::TPointHashGrid3< PointDataType, RealType >::FindPointsInBall	(	const TVector< RealType > &	QueryPoint,
		RealType	Radius,
		TFunctionRef< RealType(const PointDataType &)>	DistanceSqFunc,
		TArray< PointDataType > &	ResultsOut,
		TFunctionRef< bool(const PointDataType &)>	IgnoreFunc = `[](const PointDataType& data) { return false; }`
	)		const

inline

Find all points in grid within a given sphere. Note: Not thread-safe to update, remove or insert points during this query.

Parameters

QueryPoint	the center of the query sphere
Radius	the radius of the query sphere
DistanceSqFunc	Function you provide which measures the squared distance between QueryPoint and a Value
ResultsOut	Array that points in sphere will be added to
IgnoreFunc	optional Function you may provide which will result in a Value being ignored if IgnoreFunc(Value) returns true

Returns: the number of found points

◆ GetInvalidValue()

template<typename PointDataType , typename RealType >

PointDataType UE::Geometry::TPointHashGrid3< PointDataType, RealType >::GetInvalidValue ( ) const

inline

Invalid grid value

◆ InsertPoint()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::InsertPoint	(	const PointDataType &	Value,
		const TVector< RealType > &	Position
	)

inline

Insert at given position. This function is thread-safe.

Parameters

Value	the point/value to insert
Position	the position associated with this value

◆ InsertPointUnsafe()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::InsertPointUnsafe	(	const PointDataType &	Value,
		const TVector< RealType > &	Position
	)

inline

Insert at given position, without locking / thread-safety

Parameters

Value	the point/value to insert
Position	the position associated with this value

◆ IsCellEmpty()

template<typename PointDataType , typename RealType >

bool UE::Geometry::TPointHashGrid3< PointDataType, RealType >::IsCellEmpty ( const TVector< RealType > & Position )

inline

Test if the cell containing Position is empty. This function is thread-safe. Can be used to skip a more expensive range search, in some cases.

Returns: true if the cell containing Position is empty

◆ IsCellEmptyUnsafe()

template<typename PointDataType , typename RealType >

bool UE::Geometry::TPointHashGrid3< PointDataType, RealType >::IsCellEmptyUnsafe ( const TVector< RealType > & Position )

inline

Test if the whole cell containing Position is empty, without locking / thread-safety Can be used to skip a more expensive range search, in some cases.

Returns: true if the cell containing Position is empty

◆ RemovePoint()

template<typename PointDataType , typename RealType >

bool UE::Geometry::TPointHashGrid3< PointDataType, RealType >::RemovePoint	(	const PointDataType &	Value,
		const TVector< RealType > &	Position
	)

inline

Remove at given position. This function is thread-safe.

Parameters

Value	the point/value to remove
Position	the position associated with this value

Returns: true if the value existed at this position

◆ RemovePointUnsafe()

template<typename PointDataType , typename RealType >

bool UE::Geometry::TPointHashGrid3< PointDataType, RealType >::RemovePointUnsafe	(	const PointDataType &	Value,
		const TVector< RealType > &	Position
	)

inline

Remove at given position, without locking / thread-safety

Parameters

Value	the point/value to remove
Position	the position associated with this value

Returns: true if the value existed at this position

◆ Reserve()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::Reserve ( int32 Num )

inline

Reserve space in the underlying hash map

Parameters

Num	amount of elements to reserve

◆ Reset()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::Reset ( RealType NewCellSize )

inline

Remove all entries in the underlying hash map, without resizing or releasing any allocations, and reset the cell size.

Parameters

NewCellSize The size of grid cells. Clamped to at least a small tolerance size.

◆ UpdatePoint()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::UpdatePoint	(	const PointDataType &	Value,
		const TVector< RealType > &	OldPosition,
		const TVector< RealType > &	NewPosition
	)

inline

Move value from old to new position. This function is thread-safe.

Parameters

Value	the point/value to update
OldPosition	the current position associated with this value
NewPosition	the new position for this value

◆ UpdatePointUnsafe()

template<typename PointDataType , typename RealType >

void UE::Geometry::TPointHashGrid3< PointDataType, RealType >::UpdatePointUnsafe	(	const PointDataType &	Value,
		const TVector< RealType > &	OldPosition,
		const TVector< RealType > &	NewPosition
	)

inline

Move value from old to new position, without locking / thread-safety

Parameters

Value	the point/value to update
OldPosition	the current position associated with this value
NewPosition	the new position for this value

The documentation for this class was generated from the following file:

Engine/Source/Runtime/GeometryCore/Public/Spatial/PointHashGrid3.h

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ TPointHashGrid3()

Member Function Documentation

◆ EnumeratePointsInBall()

◆ FindAnyInRadius() [1/2]

◆ FindAnyInRadius() [2/2]

◆ FindNearestInRadius() [1/2]

◆ FindNearestInRadius() [2/2]

◆ FindPointsInBall()

◆ GetInvalidValue()

◆ InsertPoint()

◆ InsertPointUnsafe()

◆ IsCellEmpty()

◆ IsCellEmptyUnsafe()

◆ RemovePoint()

◆ RemovePointUnsafe()

◆ Reserve()

◆ Reset()

◆ UpdatePoint()

◆ UpdatePointUnsafe()