vtkCellLocator Class Reference

#include <vtkCellLocator.h>

Inheritance diagram for vtkCellLocator:

[legend]

Collaboration diagram for vtkCellLocator:

[legend]

List of all members.

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Detailed Description

octree-based spatial search object to quickly locate cells

vtkCellLocator is a spatial search object to quickly locate cells in 3D. vtkCellLocator uses a uniform-level octree subdivision, where each octant (an octant is also referred to as a bucket) carries an indication of whether it is empty or not, and each leaf octant carries a list of the cells inside of it. (An octant is not empty if it has one or more cells inside of it.) Typical operations are intersection with a line to return candidate cells, or intersection with another vtkCellLocator to return candidate cells.

Warning:

Many other types of spatial locators have been developed, such as variable depth octrees and kd-trees. These are often more efficient for the operations described here. vtkCellLocator has been designed for subclassing; so these locators can be derived if necessary.

See also:

vtkLocator vtkPointLocator vtkOBBTree

Tests:

vtkCellLocator (Tests)

Definition at line 51 of file vtkCellLocator.h.

Public Types
typedef vtkLocator	Superclass
Public Member Functions
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
virtual vtkIdList *	GetCells (int bucket)
virtual int	GetNumberOfBuckets (void)
void	FindCellsWithinBounds (double *bbox, vtkIdList *cells)
virtual void	SetNumberOfCellsPerBucket (int)
virtual int	GetNumberOfCellsPerBucket ()
virtual void	SetCacheCellBounds (int)
virtual int	GetCacheCellBounds ()
virtual void	CacheCellBoundsOn ()
virtual void	CacheCellBoundsOff ()
virtual int	IntersectWithLine (double a0[3], double a1[3], double tol, double &t, double x[3], double pcoords[3], int &subId)
virtual int	IntersectWithLine (double a0[3], double a1[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId)
virtual int	IntersectWithLine (double a0[3], double a1[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId, vtkGenericCell *cell)
void	FindClosestPoint (double x[3], double closestPoint[3], vtkIdType &cellId, int &subId, double &dist2)
void	FindClosestPoint (double x[3], double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2)
int	FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkIdType &cellId, int &subId, double &dist2)
int	FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2)
int	FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2, int &inside)
void	FindCellsAlongLine (double p1[3], double p2[3], double tolerance, vtkIdList *cells)
void	FreeSearchStructure ()
void	BuildLocator ()
void	GenerateRepresentation (int level, vtkPolyData *pd)
Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkCellLocator *	SafeDownCast (vtkObject *o)
static vtkCellLocator *	New ()
Protected Member Functions
	vtkCellLocator ()
	~vtkCellLocator ()
void	GetBucketNeighbors (int ijk[3], int ndivs, int level)
void	GetOverlappingBuckets (double x[3], int ijk[3], double dist, int prevMinLevel[3], int prevMaxLevel[3])
void	ClearCellHasBeenVisited ()
void	ClearCellHasBeenVisited (int id)
double	Distance2ToBucket (double x[3], int nei[3])
double	Distance2ToBounds (double x[3], double bounds[6])
void	MarkParents (void *, int, int, int, int, int)
void	GetChildren (int idx, int level, int children[8])
int	GenerateIndex (int offset, int numDivs, int i, int j, int k, vtkIdType &idx)
void	GenerateFace (int face, int numDivs, int i, int j, int k, vtkPoints *pts, vtkCellArray *polys)
void	ComputeOctantBounds (int i, int j, int k)
int	IsInOctantBounds (double x[3])
Protected Attributes
int	NumberOfCellsPerBucket
int	NumberOfOctants
double	Bounds [6]
int	NumberOfParents
double	H [3]
int	NumberOfDivisions
vtkIdList **	Tree
vtkNeighborCells *	Buckets
unsigned char *	CellHasBeenVisited
unsigned char	QueryNumber
int	CacheCellBounds
double(*	CellBounds )[6]
double	OctantBounds [6]

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Member Typedef Documentation

typedef vtkLocator vtkCellLocator::Superclass

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

Definition at line 54 of file vtkCellLocator.h.

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Constructor & Destructor Documentation

vtkCellLocator::vtkCellLocator

(

)

[protected]

vtkCellLocator::~vtkCellLocator

(

)

[protected]

---

Member Function Documentation

virtual const char* vtkCellLocator::GetClassName

(

)

[virtual]

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

static int vtkCellLocator::IsTypeOf

(

const char *

name

)

[static]

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

virtual int vtkCellLocator::IsA

(

const char *

name

)

[virtual]

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

static vtkCellLocator* vtkCellLocator::SafeDownCast

(

vtkObject *

o

)

[static]

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

void vtkCellLocator::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)			[virtual]

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkLocator.

Reimplemented in vtkOBBTree.

static vtkCellLocator* vtkCellLocator::New

(

)

[static]

Construct with automatic computation of divisions, averaging 25 cells per bucket.

Reimplemented from vtkObject.

Reimplemented in vtkOBBTree.

virtual void vtkCellLocator::SetNumberOfCellsPerBucket

(

int

)

[virtual]

Specify the average number of cells in each octant.

virtual int vtkCellLocator::GetNumberOfCellsPerBucket

(

)

[virtual]

Specify the average number of cells in each octant.

virtual void vtkCellLocator::SetCacheCellBounds

(

int

)

[virtual]

Boolean controls whether the bounds of each cell are computed only once and then saved. Should be 10 to 20% faster if repeatedly calling any of the FindClosestPoint routines and the extra memory won't cause disk caching (24 extra bytes per cell are required to save the bounds).

virtual int vtkCellLocator::GetCacheCellBounds

(

)

[virtual]

Boolean controls whether the bounds of each cell are computed only once and then saved. Should be 10 to 20% faster if repeatedly calling any of the FindClosestPoint routines and the extra memory won't cause disk caching (24 extra bytes per cell are required to save the bounds).

virtual void vtkCellLocator::CacheCellBoundsOn

(

)

[virtual]

Boolean controls whether the bounds of each cell are computed only once and then saved. Should be 10 to 20% faster if repeatedly calling any of the FindClosestPoint routines and the extra memory won't cause disk caching (24 extra bytes per cell are required to save the bounds).

virtual void vtkCellLocator::CacheCellBoundsOff

(

)

[virtual]

Boolean controls whether the bounds of each cell are computed only once and then saved. Should be 10 to 20% faster if repeatedly calling any of the FindClosestPoint routines and the extra memory won't cause disk caching (24 extra bytes per cell are required to save the bounds).

virtual int vtkCellLocator::IntersectWithLine	(	double	a0[3],
		double	a1[3],
		double	tol,
		double &	t,
		double	x[3],
		double	pcoords[3],
		int &	subId
	)			[virtual]

Return intersection point (if any) of finite line with cells contained in cell locator.

Reimplemented in vtkOBBTree.

virtual int vtkCellLocator::IntersectWithLine	(	double	a0[3],
		double	a1[3],
		double	tol,
		double &	t,
		double	x[3],
		double	pcoords[3],
		int &	subId,
		vtkIdType &	cellId
	)			[virtual]

Return intersection point (if any) AND the cell which was intersected by the finite line.

Reimplemented in vtkOBBTree.

virtual int vtkCellLocator::IntersectWithLine	(	double	a0[3],
		double	a1[3],
		double	tol,
		double &	t,
		double	x[3],
		double	pcoords[3],
		int &	subId,
		vtkIdType &	cellId,
		vtkGenericCell *	cell
	)			[virtual]

Return intersection point (if any) AND the cell which was intersected by the finite line. The cell is returned as a cell id and as a generic cell.

Reimplemented in vtkOBBTree.

void vtkCellLocator::FindClosestPoint	(	double	x[3],
		double	closestPoint[3],
		vtkIdType &	cellId,
		int &	subId,
		double &	dist2
	)

Return the closest point and the cell which is closest to the point x. The closest point is somewhere on a cell, it need not be one of the vertices of the cell.

void vtkCellLocator::FindClosestPoint	(	double	x[3],
		double	closestPoint[3],
		vtkGenericCell *	cell,
		vtkIdType &	cellId,
		int &	subId,
		double &	dist2
	)

Return the closest point and the cell which is closest to the point x. The closest point is somewhere on a cell, it need not be one of the vertices of the cell. This version takes in a vtkGenericCell to avoid allocating and deallocating the cell. This is much faster than the version which does not take a *cell, especially when this function is called many times in a row such as by a for loop, where the allocation and deallocation can be done only once outside the for loop. If a cell is found, "cell" contains the points and ptIds for the cell "cellId" upon exit.

int vtkCellLocator::FindClosestPointWithinRadius	(	double	x[3],
		double	radius,
		double	closestPoint[3],
		vtkIdType &	cellId,
		int &	subId,
		double &	dist2
	)

Return the closest point within a specified radius and the cell which is closest to the point x. The closest point is somewhere on a cell, it need not be one of the vertices of the cell. This method returns 1 if a point is found within the specified radius. If there are no cells within the specified radius, the method returns 0 and the values of closestPoint, cellId, subId, and dist2 are undefined.

int vtkCellLocator::FindClosestPointWithinRadius	(	double	x[3],
		double	radius,
		double	closestPoint[3],
		vtkGenericCell *	cell,
		vtkIdType &	cellId,
		int &	subId,
		double &	dist2
	)

Return the closest point within a specified radius and the cell which is closest to the point x. The closest point is somewhere on a cell, it need not be one of the vertices of the cell. This method returns 1 if a point is found within the specified radius. If there are no cells within the specified radius, the method returns 0 and the values of closestPoint, cellId, subId, and dist2 are undefined. This version takes in a vtkGenericCell to avoid allocating and deallocating the cell. This is much faster than the version which does not take a *cell, especially when this function is called many times in a row such as by a for loop, where the allocation and deallocation can be done only once outside the for loop. If a closest point is found, "cell" contains the points and ptIds for the cell "cellId" upon exit.

int vtkCellLocator::FindClosestPointWithinRadius	(	double	x[3],
		double	radius,
		double	closestPoint[3],
		vtkGenericCell *	cell,
		vtkIdType &	cellId,
		int &	subId,
		double &	dist2,
		int &	inside
	)

Return the closest point within a specified radius and the cell which is closest to the point x. The closest point is somewhere on a cell, it need not be one of the vertices of the cell. This method returns 1 if a point is found within the specified radius. If there are no cells within the specified radius, the method returns 0 and the values of closestPoint, cellId, subId, and dist2 are undefined. This version takes in a vtkGenericCell to avoid allocating and deallocating the cell. This is much faster than the version which does not take a *cell, especially when this function is called many times in a row such as by a for loop, where the allocation and dealloction can be done only once outside the for loop. If a closest point is found, "cell" contains the points and ptIds for the cell "cellId" upon exit. If a closest point is found, inside returns the return value of the EvaluatePosition call to the closest cell; inside(=1) or outside(=0).

virtual vtkIdList* vtkCellLocator::GetCells

(

int

bucket

)

[virtual]

Get the cells in a particular bucket.

virtual int vtkCellLocator::GetNumberOfBuckets

(

void

)

[virtual]

Return number of buckets available. Insure that the locator has been built before attempting to access buckets (octants).

void vtkCellLocator::FindCellsWithinBounds	(	double *	bbox,
		vtkIdList *	cells
	)

Return a list of unique cell ids inside of a given bounding box. The user must provide the vtkIdList to populate. This method returns data only after the locator has been built.

void vtkCellLocator::FindCellsAlongLine	(	double	p1[3],
		double	p2[3],
		double	tolerance,
		vtkIdList *	cells
	)

Given a finite line defined by the two points (p1,p2), return the list of unique cell ids in the buckets containing the line. It is possible that an empty cell list is returned. The user must provide the vtkIdList to populate. This method returns data only after the locator has been built.

void vtkCellLocator::FreeSearchStructure

(

)

[virtual]

Satisfy vtkLocator abstract interface.

Implements vtkLocator.

Reimplemented in vtkOBBTree.

void vtkCellLocator::BuildLocator

(

)

[virtual]

Satisfy vtkLocator abstract interface.

Implements vtkLocator.

Reimplemented in vtkOBBTree.

void vtkCellLocator::GenerateRepresentation	(	int	level,
		vtkPolyData *	pd
	)			[virtual]

Satisfy vtkLocator abstract interface.

Implements vtkLocator.

Reimplemented in vtkOBBTree.

void vtkCellLocator::GetBucketNeighbors	(	int	ijk[3],
		int	ndivs,
		int	level
	)			[protected]

void vtkCellLocator::GetOverlappingBuckets	(	double	x[3],
		int	ijk[3],
		double	dist,
		int	prevMinLevel[3],
		int	prevMaxLevel[3]
	)			[protected]

void vtkCellLocator::ClearCellHasBeenVisited

(

)

[protected]

void vtkCellLocator::ClearCellHasBeenVisited

(

int

id

)

[protected]

double vtkCellLocator::Distance2ToBucket	(	double	x[3],
		int	nei[3]
	)			[protected]

double vtkCellLocator::Distance2ToBounds	(	double	x[3],
		double	bounds[6]
	)			[protected]

void vtkCellLocator::MarkParents	(	void *	,
		int	,
		int	,
		int	,
		int	,
		int
	)			[protected]

void vtkCellLocator::GetChildren	(	int	idx,
		int	level,
		int	children[8]
	)			[protected]

int vtkCellLocator::GenerateIndex	(	int	offset,
		int	numDivs,
		int	i,
		int	j,
		int	k,
		vtkIdType &	idx
	)			[protected]

void vtkCellLocator::GenerateFace	(	int	face,
		int	numDivs,
		int	i,
		int	j,
		int	k,
		vtkPoints *	pts,
		vtkCellArray *	polys
	)			[protected]

void vtkCellLocator::ComputeOctantBounds	(	int	i,
		int	j,
		int	k
	)			[protected]

int vtkCellLocator::IsInOctantBounds

(

double

x[3]

)

[inline, protected]

Definition at line 249 of file vtkCellLocator.h.

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Member Data Documentation

int vtkCellLocator::NumberOfCellsPerBucket [protected]

Definition at line 224 of file vtkCellLocator.h.

int vtkCellLocator::NumberOfOctants [protected]

Definition at line 225 of file vtkCellLocator.h.

double vtkCellLocator::Bounds[6] [protected]

Definition at line 226 of file vtkCellLocator.h.

int vtkCellLocator::NumberOfParents [protected]

Definition at line 227 of file vtkCellLocator.h.

double vtkCellLocator::H[3] [protected]

Definition at line 228 of file vtkCellLocator.h.

int vtkCellLocator::NumberOfDivisions [protected]

Definition at line 229 of file vtkCellLocator.h.

vtkIdList** vtkCellLocator::Tree [protected]

Reimplemented in vtkOBBTree.

Definition at line 230 of file vtkCellLocator.h.

vtkNeighborCells* vtkCellLocator::Buckets [protected]

Definition at line 239 of file vtkCellLocator.h.

unsigned char* vtkCellLocator::CellHasBeenVisited [protected]

Definition at line 240 of file vtkCellLocator.h.

unsigned char vtkCellLocator::QueryNumber [protected]

Definition at line 241 of file vtkCellLocator.h.

int vtkCellLocator::CacheCellBounds [protected]

Definition at line 242 of file vtkCellLocator.h.

double(* vtkCellLocator::CellBounds)[6] [protected]

Definition at line 244 of file vtkCellLocator.h.

double vtkCellLocator::OctantBounds[6] [protected]

Definition at line 248 of file vtkCellLocator.h.

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

• dox/Filtering/vtkCellLocator.h