vtkPolygon Class Reference

a cell that represents an n-sided polygon More...

#include <vtkPolygon.h>

Inheritance diagram for vtkPolygon:

Collaboration diagram for vtkPolygon:

Public Types
typedef vtkCell	Superclass
Public Types inherited from vtkCell
typedef vtkObject	Superclass
Public Types inherited from vtkObject
typedef vtkObjectBase	Superclass

Public Member Functions
virtual int	IsA (const char *type)
vtkPolygon *	NewInstance () const
void	PrintSelf (ostream &os, vtkIndent indent)
double	ComputeArea ()
virtual void	InterpolateFunctions (double x[3], double *sf)
int	Triangulate (vtkIdList *outTris)
int	NonDegenerateTriangulate (vtkIdList *outTris)
int	GetCellType ()
int	GetCellDimension ()
int	GetNumberOfEdges ()
int	GetNumberOfFaces ()
vtkCell *	GetEdge (int edgeId)
vtkCell *	GetFace (int)
int	CellBoundary (int subId, double pcoords[3], vtkIdList *pts)
void	Contour (double value, vtkDataArray *cellScalars, vtkIncrementalPointLocator *locator, vtkCellArray *verts, vtkCellArray *lines, vtkCellArray *polys, vtkPointData *inPd, vtkPointData *outPd, vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd)
void	Clip (double value, vtkDataArray *cellScalars, vtkIncrementalPointLocator *locator, vtkCellArray *tris, vtkPointData *inPd, vtkPointData *outPd, vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd, int insideOut)
int	EvaluatePosition (double x[3], double *closestPoint, int &subId, double pcoords[3], double &dist2, double *weights)
void	EvaluateLocation (int &subId, double pcoords[3], double x[3], double *weights)
int	IntersectWithLine (double p1[3], double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId)
int	Triangulate (int index, vtkIdList *ptIds, vtkPoints *pts)
void	Derivatives (int subId, double pcoords[3], double *values, int dim, double *derivs)
int	IsPrimaryCell ()
int	ParameterizePolygon (double p0[3], double p10[3], double &l10, double p20[3], double &l20, double n[3])
virtual bool	GetUseMVCInterpolation ()
virtual void	SetUseMVCInterpolation (bool)
Public Member Functions inherited from vtkCell
vtkCell *	NewInstance () const
void	Initialize (int npts, vtkIdType *pts, vtkPoints *p)
virtual void	ShallowCopy (vtkCell *c)
virtual void	DeepCopy (vtkCell *c)
virtual int	IsLinear ()
virtual int	IsExplicitCell ()
vtkPoints *	GetPoints ()
vtkIdType	GetNumberOfPoints ()
vtkIdList *	GetPointIds ()
vtkIdType	GetPointId (int ptId)
void	GetBounds (double bounds[6])
double *	GetBounds ()
double	GetLength2 ()
virtual int	GetParametricCenter (double pcoords[3])
virtual double	GetParametricDistance (double pcoords[3])
virtual double *	GetParametricCoords ()
virtual int	RequiresInitialization ()
virtual void	Initialize ()
virtual int	RequiresExplicitFaceRepresentation ()
virtual void	SetFaces (vtkIdType *vtkNotUsed(faces))
virtual vtkIdType *	GetFaces ()
virtual void	InterpolateFunctions (double vtkNotUsed(pcoords)[3], double *vtkNotUsed(weight))
virtual void	InterpolateDerivs (double vtkNotUsed(pcoords)[3], double *vtkNotUsed(derivs))
Public Member Functions inherited from vtkObject
vtkObject *	NewInstance () const
virtual void	DebugOn ()
virtual void	DebugOff ()
bool	GetDebug ()
void	SetDebug (bool debugFlag)
virtual void	Modified ()
virtual unsigned long	GetMTime ()
unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
unsigned long	AddObserver (const char *event, vtkCommand *, float priority=0.0f)
vtkCommand *	GetCommand (unsigned long tag)
void	RemoveObserver (vtkCommand *)
void	RemoveObservers (unsigned long event, vtkCommand *)
void	RemoveObservers (const char *event, vtkCommand *)
int	HasObserver (unsigned long event, vtkCommand *)
int	HasObserver (const char *event, vtkCommand *)
void	RemoveObserver (unsigned long tag)
void	RemoveObservers (unsigned long event)
void	RemoveObservers (const char *event)
void	RemoveAllObservers ()
int	HasObserver (unsigned long event)
int	HasObserver (const char *event)
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
int	InvokeEvent (unsigned long event, void *callData)
int	InvokeEvent (const char *event, void *callData)
int	InvokeEvent (unsigned long event)
int	InvokeEvent (const char *event)
Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const
virtual void	Delete ()
virtual void	FastDelete ()
void	Print (ostream &os)
virtual void	Register (vtkObjectBase *o)
virtual void	UnRegister (vtkObjectBase *o)
void	SetReferenceCount (int)
void	PrintRevisions (ostream &)
virtual void	PrintHeader (ostream &os, vtkIndent indent)
virtual void	PrintTrailer (ostream &os, vtkIndent indent)
int	GetReferenceCount ()

Static Public Member Functions
static vtkPolygon *	New ()
static int	IsTypeOf (const char *type)
static vtkPolygon *	SafeDownCast (vtkObjectBase *o)
static void	ComputeNormal (int numPts, double *pts, double n[3])
static void	ComputeNormal (vtkPoints *p, int numPts, vtkIdType *pts, double n[3])
static void	ComputeNormal (vtkPoints *p, double n[3])
static void	ComputeNormal (vtkIdTypeArray *ids, vtkPoints *pts, double n[3])
static void	ComputeCentroid (vtkIdTypeArray *ids, vtkPoints *pts, double centroid[3])
static double	ComputeArea (vtkPoints *p, vtkIdType numPts, vtkIdType *pts, double normal[3])
static int	PointInPolygon (double x[3], int numPts, double *pts, double bounds[6], double n[3])
static double	DistanceToPolygon (double x[3], int numPts, double *pts, double bounds[6], double closest[3])
static int	IntersectPolygonWithPolygon (int npts, double *pts, double bounds[6], int npts2, double *pts2, double bounds2[3], double tol, double x[3])
static int	IntersectConvex2DCells (vtkCell *cell1, vtkCell *cell2, double tol, double p0[3], double p1[3])
Static Public Member Functions inherited from vtkCell
static int	IsTypeOf (const char *type)
static vtkCell *	SafeDownCast (vtkObjectBase *o)
Static Public Member Functions inherited from vtkObject
static int	IsTypeOf (const char *type)
static vtkObject *	SafeDownCast (vtkObjectBase *o)
static vtkObject *	New ()
static void	BreakOnError ()
static void	SetGlobalWarningDisplay (int val)
static void	GlobalWarningDisplayOn ()
static void	GlobalWarningDisplayOff ()
static int	GetGlobalWarningDisplay ()
Static Public Member Functions inherited from vtkObjectBase
static int	IsTypeOf (const char *name)
static vtkObjectBase *	New ()

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const
	vtkPolygon ()
	~vtkPolygon ()
void	InterpolateFunctionsUsingMVC (double x[3], double *weights)
int	EarCutTriangulation ()
Protected Member Functions inherited from vtkCell
	vtkCell ()
	~vtkCell ()
Protected Member Functions inherited from vtkObject
	vtkObject ()
virtual	~vtkObject ()
virtual void	RegisterInternal (vtkObjectBase *, int check)
virtual void	UnRegisterInternal (vtkObjectBase *, int check)
void	InternalGrabFocus (vtkCommand *mouseEvents, vtkCommand *keypressEvents=NULL)
void	InternalReleaseFocus ()
Protected Member Functions inherited from vtkObjectBase
	vtkObjectBase ()
virtual	~vtkObjectBase ()
virtual void	CollectRevisions (ostream &)
virtual void	ReportReferences (vtkGarbageCollector *)
	vtkObjectBase (const vtkObjectBase &)
void	operator= (const vtkObjectBase &)

Protected Attributes
double	Tolerance
int	SuccessfulTriangulation
double	Normal [3]
vtkIdList *	Tris
vtkTriangle *	Triangle
vtkQuad *	Quad
vtkDoubleArray *	TriScalars
vtkLine *	Line
bool	UseMVCInterpolation
Protected Attributes inherited from vtkCell
double	Bounds [6]
Protected Attributes inherited from vtkObject
bool	Debug
vtkTimeStamp	MTime
vtkSubjectHelper *	SubjectHelper
Protected Attributes inherited from vtkObjectBase
vtkAtomicInt32	ReferenceCount
vtkWeakPointerBase **	WeakPointers

Additional Inherited Members
Public Attributes inherited from vtkCell
vtkPoints *	Points
vtkIdList *	PointIds

Detailed Description

a cell that represents an n-sided polygon

vtkPolygon is a concrete implementation of vtkCell to represent a 2D n-sided polygon. The polygons cannot have any internal holes, and cannot self-intersect. Define the polygon with n-points ordered in the counter- clockwise direction; do not repeat the last point.

Examples:

vtkPolygon (Examples)

Tests:

vtkPolygon (Tests)

Definition at line 44 of file vtkPolygon.h.

Member Typedef Documentation

typedef vtkCell vtkPolygon::Superclass

Definition at line 48 of file vtkPolygon.h.

Constructor & Destructor Documentation

vtkPolygon::vtkPolygon ( )

protected

vtkPolygon::~vtkPolygon ( )

protected

Member Function Documentation

static vtkPolygon* vtkPolygon::New ( )

static

static int vtkPolygon::IsTypeOf ( const char *  type )

static

virtual int vtkPolygon::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 vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkCell.

static vtkPolygon* vtkPolygon::SafeDownCast ( vtkObjectBase *  o )

static

virtual vtkObjectBase* vtkPolygon::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkCell.

vtkPolygon* vtkPolygon::NewInstance

(

)

const

void vtkPolygon::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 vtkCell.

int vtkPolygon::GetCellType ( )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

Definition at line 53 of file vtkPolygon.h.

int vtkPolygon::GetCellDimension ( )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

Definition at line 54 of file vtkPolygon.h.

int vtkPolygon::GetNumberOfEdges ( )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

Definition at line 55 of file vtkPolygon.h.

int vtkPolygon::GetNumberOfFaces ( )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

Definition at line 56 of file vtkPolygon.h.

vtkCell* vtkPolygon::GetEdge ( int  edgeId )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

vtkCell* vtkPolygon::GetFace ( int  )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

Definition at line 58 of file vtkPolygon.h.

int vtkPolygon::CellBoundary ( int  subId, double  pcoords[3], vtkIdList *  pts  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

void vtkPolygon::Contour ( double  value, vtkDataArray *  cellScalars, vtkIncrementalPointLocator *  locator, vtkCellArray *  verts, vtkCellArray *  lines, vtkCellArray *  polys, vtkPointData *  inPd, vtkPointData *  outPd, vtkCellData *  inCd, vtkIdType  cellId, vtkCellData *  outCd  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

void vtkPolygon::Clip ( double  value, vtkDataArray *  cellScalars, vtkIncrementalPointLocator *  locator, vtkCellArray *  tris, vtkPointData *  inPd, vtkPointData *  outPd, vtkCellData *  inCd, vtkIdType  cellId, vtkCellData *  outCd, int  insideOut  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

int vtkPolygon::EvaluatePosition ( double  x[3], double *  closestPoint, int &  subId, double  pcoords[3], double &  dist2, double *  weights  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

void vtkPolygon::EvaluateLocation ( int &  subId, double  pcoords[3], double  x[3], double *  weights  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

int vtkPolygon::IntersectWithLine ( double  p1[3], double  p2[3], double  tol, double &  t, double  x[3], double  pcoords[3], int &  subId  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

int vtkPolygon::Triangulate ( int  index, vtkIdList *  ptIds, vtkPoints *  pts  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

void vtkPolygon::Derivatives ( int  subId, double  pcoords[3], double *  values, int  dim, double *  derivs  )

virtual

See the vtkCell API for descriptions of these methods.

Implements vtkCell.

int vtkPolygon::IsPrimaryCell ( )

inlinevirtual

See the vtkCell API for descriptions of these methods.

Reimplemented from vtkCell.

Definition at line 80 of file vtkPolygon.h.

double vtkPolygon::ComputeArea

(

)

Compute the area of a polygon. This is a convenience function which simply calls static double ComputeArea(vtkPoints *p, vtkIdType numPts, vtkIdType *pts, double normal[3]); with the appropriate parameters from the instantiated vtkPolygon.

virtual void vtkPolygon::InterpolateFunctions ( double  x[3], double *  sf  )

virtual

Compute the interpolation functions/derivatives. (aka shape functions/derivatives) Two interpolation algorithms are available: 1/r^2 and Mean Value Coordinate. The former is used by default. To use the second algorithm, set UseMVCInterpolation to be true. The function assumes the input point lies on the polygon plane without checking that.

static void vtkPolygon::ComputeNormal ( vtkPoints *  p, int  numPts, vtkIdType *  pts, double  n[3]  )

static

Polygon specific methods.

static void vtkPolygon::ComputeNormal ( vtkPoints *  p, double  n[3]  )

static

Polygon specific methods.

static void vtkPolygon::ComputeNormal ( vtkIdTypeArray *  ids, vtkPoints *  pts, double  n[3]  )

static

Polygon specific methods.

static void vtkPolygon::ComputeNormal ( int  numPts, double *  pts, double  n[3]  )

static

Compute the polygon normal from an array of points. This version assumes that the polygon is convex, and looks for the first valid normal.

static void vtkPolygon::ComputeCentroid ( vtkIdTypeArray *  ids, vtkPoints *  pts, double  centroid[3]  )

static

Compute the centroid of a set of points.

static double vtkPolygon::ComputeArea ( vtkPoints *  p, vtkIdType  numPts, vtkIdType *  pts, double  normal[3]  )

static

Compute the area of a polygon in 3D. The area is returned, as well as the normal (a side effect of using this method). If you desire to compute the area of a triangle, use vtkTriangleArea which is faster. If you already have a vtkPolygon instantiated, a convenience function, ComputeArea() is provided.

int vtkPolygon::ParameterizePolygon	(	double	p0[3],
		double	p10[3],
		double &	l10,
		double	p20[3],
		double &	l20,
		double	n[3]
	)

Create a local s-t coordinate system for a polygon. The point p0 is the origin of the local system, p10 is s-axis vector, and p20 is the t-axis vector. (These are expressed in the modeling coordinate system and are vectors of dimension [3].) The values l20 and l20 are the lengths of the vectors p10 and p20, and n is the polygon normal.

static int vtkPolygon::PointInPolygon ( double  x[3], int  numPts, double *  pts, double  bounds[6], double  n[3]  )

static

Determine whether point is inside polygon. Function uses ray-casting to determine if point is inside polygon. Works for arbitrary polygon shape (e.g., non-convex). Returns 0 if point is not in polygon; 1 if it is. Can also return -1 to indicate degenerate polygon.

int vtkPolygon::Triangulate

(

vtkIdList *

outTris

)

Triangulate this polygon. The user must provide the vtkIdList outTris. On output, the outTris list contains the ids of the points defining the triangulation. The ids are ordered into groups of three: each three-group defines one triangle.

int vtkPolygon::NonDegenerateTriangulate

(

vtkIdList *

outTris

)

Same as Triangulate(vtkIdList *outTris) but with a first pass to split the polygon into non-degenerate polygons.

static double vtkPolygon::DistanceToPolygon ( double  x[3], int  numPts, double *  pts, double  bounds[6], double  closest[3]  )

static

Compute the distance of a point to a polygon. The closest point on the polygon is also returned. The bounds should be provided to accelerate the computation.

static int vtkPolygon::IntersectPolygonWithPolygon ( int  npts, double *  pts, double  bounds[6], int  npts2, double *  pts2, double  bounds2[3], double  tol, double  x[3]  )

static

Method intersects two polygons. You must supply the number of points and point coordinates (npts, *pts) and the bounding box (bounds) of the two polygons. Also supply a tolerance squared for controlling error. The method returns 1 if there is an intersection, and 0 if not. A single point of intersection x[3] is also returned if there is an intersection.

static int vtkPolygon::IntersectConvex2DCells ( vtkCell *  cell1, vtkCell *  cell2, double  tol, double  p0[3], double  p1[3]  )

static

Intersect two convex 2D polygons to produce a line segment as output. The return status of the methods indicated no intersection (returns 0); a single point of intersection (returns 1); or a line segment (i.e., two points of intersection, returns 2). The points of intersection are returned in the arrays p0 and p1. If less than two points of intersection are generated then p1 and/or p0 may be indeterminiate. Finally, if the two convex polygons are parallel, then "0" is returned (i.e., no intersection) even if the triangles lie on one another.

virtual bool vtkPolygon::GetUseMVCInterpolation ( )

virtual

Set/Get the flag indicating whether to use Mean Value Coordinate for the interpolation. If true, InterpolateFunctions() uses the Mean Value Coordinate to compute weights. Otherwise, the conventional 1/r^2 method is used. The UseMVCInterpolation parameter is set to false by default.

virtual void vtkPolygon::SetUseMVCInterpolation ( bool  )

virtual

Set/Get the flag indicating whether to use Mean Value Coordinate for the interpolation. If true, InterpolateFunctions() uses the Mean Value Coordinate to compute weights. Otherwise, the conventional 1/r^2 method is used. The UseMVCInterpolation parameter is set to false by default.

void vtkPolygon::InterpolateFunctionsUsingMVC ( double  x[3], double *  weights  )

protected

int vtkPolygon::EarCutTriangulation ( )

protected

A fast triangulation method. Uses recursive divide and conquer based on plane splitting to reduce loop into triangles. The cell (e.g., triangle) is presumed properly initialized (i.e., Points and PointIds).

Member Data Documentation

double vtkPolygon::Tolerance

protected

Definition at line 208 of file vtkPolygon.h.

int vtkPolygon::SuccessfulTriangulation

protected

Definition at line 209 of file vtkPolygon.h.

double vtkPolygon::Normal[3]

protected

Definition at line 210 of file vtkPolygon.h.

vtkIdList* vtkPolygon::Tris

protected

Definition at line 211 of file vtkPolygon.h.

vtkTriangle* vtkPolygon::Triangle

protected

Definition at line 212 of file vtkPolygon.h.

vtkQuad* vtkPolygon::Quad

protected

Definition at line 213 of file vtkPolygon.h.

vtkDoubleArray* vtkPolygon::TriScalars

protected

Definition at line 214 of file vtkPolygon.h.

vtkLine* vtkPolygon::Line

protected

Definition at line 215 of file vtkPolygon.h.

bool vtkPolygon::UseMVCInterpolation

protected

Definition at line 219 of file vtkPolygon.h.

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

• /home/boeckb/code/depot/group-kitware/vtk/build-release/Utilities/Doxygen/dox/Common/DataModel/vtkPolygon.h