how to decide whether a linear approximation to nonlinear geometry or field should be subdivided More...

#include <vtkEdgeSubdivisionCriterion.h>

Inheritance diagram for vtkEdgeSubdivisionCriterion:

Collaboration diagram for vtkEdgeSubdivisionCriterion:

Public Types
typedef vtkObject	Superclass

Public Member Functions
virtual vtkTypeBool	IsA (const char *type)
	Return 1 if this class is the same type of (or a subclass of) the named class. More...

vtkEdgeSubdivisionCriterion *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent) override
	Methods invoked by print to print information about the object including superclasses. More...

virtual bool	EvaluateEdge (const double p0, double p1, const double *p2, int field_start)=0
	You must implement this member function in a subclass. More...

virtual int	PassField (int sourceId, int sourceSize, vtkStreamingTessellator *t)
	This is a helper routine called by `PassFields()` which you may also call directly; it adds sourceSize to the size of the output vertex field values. More...

virtual void	ResetFieldList ()
	Don't pass any field values in the vertex pointer. More...

virtual bool	DontPassField (int sourceId, vtkStreamingTessellator *t)
	This does the opposite of `PassField()`; it removes a field from the output (assuming the field was set to be passed). More...

const int *	GetFieldIds () const
	Return the map from output field id to input field ids. More...

const int *	GetFieldOffsets () const
	Return the offset into an output vertex array of all fields. More...

int	GetOutputField (int fieldId) const
	Return the output ID of an input field. More...

int	GetNumberOfFields () const
	Return the number of fields being evaluated at each output vertex. More...

Public Member Functions inherited from vtkObject
	vtkBaseTypeMacro (vtkObject, vtkObjectBase)

virtual void	DebugOn ()
	Turn debugging output on. More...

virtual void	DebugOff ()
	Turn debugging output off. More...

bool	GetDebug ()
	Get the value of the debug flag. More...

void	SetDebug (bool debugFlag)
	Set the value of the debug flag. More...

virtual void	Modified ()
	Update the modification time for this object. More...

virtual vtkMTimeType	GetMTime ()
	Return this object's modified time. More...

void	RemoveObserver (unsigned long tag)

void	RemoveObservers (unsigned long event)

void	RemoveObservers (const char *event)

void	RemoveAllObservers ()

vtkTypeBool	HasObserver (unsigned long event)

vtkTypeBool	HasObserver (const char *event)

int	InvokeEvent (unsigned long event)

int	InvokeEvent (const char *event)

unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

unsigned long	AddObserver (const char event, vtkCommand , float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkCommand *	GetCommand (unsigned long tag)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObserver (vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObservers (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObservers (const char event, vtkCommand )
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkTypeBool	HasObserver (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkTypeBool	HasObserver (const char event, vtkCommand )
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)
	Allow user to set the AbortFlagOn() with the return value of the callback method. More...

int	InvokeEvent (unsigned long event, void *callData)
	This method invokes an event and return whether the event was aborted or not. More...

int	InvokeEvent (const char event, void callData)
	This method invokes an event and return whether the event was aborted or not. More...

Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const
	Return the class name as a string. More...

virtual void	Delete ()
	Delete a VTK object. More...

virtual void	FastDelete ()
	Delete a reference to this object. More...

void	InitializeObjectBase ()

void	Print (ostream &os)
	Print an object to an ostream. More...

virtual void	Register (vtkObjectBase *o)
	Increase the reference count (mark as used by another object). More...

virtual void	UnRegister (vtkObjectBase *o)
	Decrease the reference count (release by another object). More...

int	GetReferenceCount ()
	Return the current reference count of this object. More...

void	SetReferenceCount (int)
	Sets the reference count. More...

void	PrintRevisions (ostream &)
	Legacy. More...

virtual void	PrintHeader (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses. More...

virtual void	PrintTrailer (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses. More...

Static Public Member Functions
static vtkTypeBool	IsTypeOf (const char *type)

static vtkEdgeSubdivisionCriterion *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkObject
static vtkObject *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...

static void	BreakOnError ()
	This method is called when vtkErrorMacro executes. More...

static void	SetGlobalWarningDisplay (int val)
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static void	GlobalWarningDisplayOn ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static void	GlobalWarningDisplayOff ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static int	GetGlobalWarningDisplay ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

Static Public Member Functions inherited from vtkObjectBase
static vtkTypeBool	IsTypeOf (const char *name)
	Return 1 if this class type is the same type of (or a subclass of) the named class. More...

static vtkObjectBase *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkEdgeSubdivisionCriterion ()

	~vtkEdgeSubdivisionCriterion () override

bool	ViewDependentEval (const double p0, double p1, double p1_actual, const double p2, int field_start, vtkMatrix4x4 viewtrans, const double pixelSize, double allowableChordErr) const
	Perform the core logic for a view-dependent subdivision. More...

bool	FixedFieldErrorEval (const double p0, double p1, double p1_actual, const double p2, int field_start, int field_criteria, double *allowableFieldErr) const
	Perform the core logic for a fixed multi-criterion, scalar-field based subdivision. More...

Protected Member Functions inherited from vtkObject
	vtkObject ()

	~vtkObject () override

void	RegisterInternal (vtkObjectBase *, vtkTypeBool check) override

void	UnRegisterInternal (vtkObjectBase *, vtkTypeBool check) override

void	InternalGrabFocus (vtkCommand mouseEvents, vtkCommand keypressEvents=nullptr)
	These methods allow a command to exclusively grab all events. More...

void	InternalReleaseFocus ()
	These methods allow a command to exclusively grab all events. More...

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
int *	FieldIds

int *	FieldOffsets

int	NumberOfFields

Protected Attributes inherited from vtkObject
bool	Debug

vtkTimeStamp	MTime

vtkSubjectHelper *	SubjectHelper

Protected Attributes inherited from vtkObjectBase
vtkAtomicInt32	ReferenceCount

vtkWeakPointerBase **	WeakPointers

Detailed Description

how to decide whether a linear approximation to nonlinear geometry or field should be subdivided

Descendants of this abstract class are used to decide whether a piecewise linear approximation (triangles, lines, ... ) to some nonlinear geometry should be subdivided. This decision may be based on an absolute error metric (chord error) or on some view-dependent metric (chord error compared to device resolution) or on some abstract metric (color error). Or anything else, really. Just so long as you implement the EvaluateEdge member, all will be well.

See also: vtkDataSetSubdivisionAlgorithm vtkStreamingTessellator

Tests:: vtkEdgeSubdivisionCriterion (Tests)

Definition at line 45 of file vtkEdgeSubdivisionCriterion.h.

Member Typedef Documentation

typedef vtkObject vtkEdgeSubdivisionCriterion::Superclass

Definition at line 48 of file vtkEdgeSubdivisionCriterion.h.

Constructor & Destructor Documentation

vtkEdgeSubdivisionCriterion::vtkEdgeSubdivisionCriterion ( )

protected

vtkEdgeSubdivisionCriterion::~vtkEdgeSubdivisionCriterion ( )

overrideprotected

Member Function Documentation

static vtkTypeBool vtkEdgeSubdivisionCriterion::IsTypeOf ( const char * type )

static

virtual vtkTypeBool vtkEdgeSubdivisionCriterion::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 vtkObjectBase.

Reimplemented in vtkDataSetEdgeSubdivisionCriterion.

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

static

virtual vtkObjectBase* vtkEdgeSubdivisionCriterion::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented in vtkDataSetEdgeSubdivisionCriterion.

vtkEdgeSubdivisionCriterion* vtkEdgeSubdivisionCriterion::NewInstance ( ) const

void vtkEdgeSubdivisionCriterion::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)

overridevirtual

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 vtkObject.

virtual bool vtkEdgeSubdivisionCriterion::EvaluateEdge	(	const double *	p0,
		double *	p1,
		const double *	p2,
		int	field_start
	)

pure virtual

You must implement this member function in a subclass.

It will be called by vtkStreamingTessellator for each edge in each primitive that vtkStreamingTessellator generates.

Implemented in vtkDataSetEdgeSubdivisionCriterion.

virtual int vtkEdgeSubdivisionCriterion::PassField	(	int	sourceId,
		int	sourceSize,
		vtkStreamingTessellator *	t
	)

virtual

This is a helper routine called by PassFields() which you may also call directly; it adds sourceSize to the size of the output vertex field values.

The offset of the sourceId field in the output vertex array is returned. -1 is returned if sourceSize would force the output to have more than vtkStreamingTessellator::MaxFieldSize field values per vertex.

virtual void vtkEdgeSubdivisionCriterion::ResetFieldList ( )

virtual

Don't pass any field values in the vertex pointer.

This is used to reset the list of fields to pass after a successful run of vtkStreamingTessellator.

virtual bool vtkEdgeSubdivisionCriterion::DontPassField	(	int	sourceId,
		vtkStreamingTessellator *	t
	)

virtual

This does the opposite of PassField(); it removes a field from the output (assuming the field was set to be passed).

Returns true if any action was taken, false otherwise.

const int * vtkEdgeSubdivisionCriterion::GetFieldIds ( ) const

inline

Return the map from output field id to input field ids.

That is, field i of any output vertex from vtkStreamingTessellator will be associated with GetFieldIds()[i] on the input mesh.

Definition at line 184 of file vtkEdgeSubdivisionCriterion.h.

const int * vtkEdgeSubdivisionCriterion::GetFieldOffsets ( ) const

inline

Return the offset into an output vertex array of all fields.

That is, field i of any output vertex, p, from vtkStreamingTessellator will have its first entry at p[GetFieldOffsets()[i] ] .

Definition at line 185 of file vtkEdgeSubdivisionCriterion.h.

int vtkEdgeSubdivisionCriterion::GetOutputField ( int fieldId ) const

Return the output ID of an input field.

Returns -1 if fieldId is not set to be passed to the output.

int vtkEdgeSubdivisionCriterion::GetNumberOfFields ( ) const

inline

Return the number of fields being evaluated at each output vertex.

This is the length of the arrays returned by GetFieldIds() and GetFieldOffsets().

Definition at line 186 of file vtkEdgeSubdivisionCriterion.h.

bool vtkEdgeSubdivisionCriterion::ViewDependentEval	(	const double *	p0,
		double *	p1,
		double *	p1_actual,
		const double *	p2,
		int	field_start,
		vtkMatrix4x4 *	viewtrans,
		const double *	pixelSize,
		double	allowableChordErr
	)		const

protected

Perform the core logic for a view-dependent subdivision.

Returns true if subdivision should occur, false otherwise. This is to be used by subclasses once the mesh-specific evaluation routines have been called to get the actual (as opposed to linearly interpolated) midpoint coordinates. Currently, this handles only geometry, but could conceivably test scalar fields as well.

Parameters

p0	is the first endpoint of the edge
p1	is the linearly interpolated midpoint of the edge
p1_actual	is the actual midpoint of the edge
p2	is the second endpoint of the edge
field_start	is the offset into the above arrays indicating where the scalar field values start (when isosurfacing, the embedding dimension may be smaller than the number of parametric coordinates).
viewtrans	is the viewing transform (from model to screen coordinates). Applying this transform to p0, p1, etc., should yield screen-space coordinates.
pixelSize	is the width and height of a pixel in screen space coordinates.
allowableChordErr	is the maximum allowable distance between p1 and p1_actual, in multiples of pixelSize, before subdivision will occur.

bool vtkEdgeSubdivisionCriterion::FixedFieldErrorEval	(	const double *	p0,
		double *	p1,
		double *	p1_actual,
		const double *	p2,
		int	field_start,
		int	field_criteria,
		double *	allowableFieldErr
	)		const

protected

Perform the core logic for a fixed multi-criterion, scalar-field based subdivision.

Returns true if subdivision should occur, false otherwise. This is to be used by subclasses once the mesh-specific evaluation routines have been called to get the actual (as opposed to linearly interpolated) midpoint geometry and field values. Only field values are tested (not geometry) because you can save yourself field evaluations if you check the geometry yourself and it fails the test.

Parameters

p0	is the first endpoint of the edge
p1	is the linearly interpolated midpoint of the edge
p1_actual	is the actual midpoint of the edge
p2	is the second endpoint of the edge
field_start	is the offset into the above arrays indicating where the scalar field values start (when isosurfacing, the embedding dimension may be smaller than the number of parametric coordinates).
field_criteria	is a bitfield specifying which fields (of the fields specified by PassField or PassFields) are to be considered for subdivision. Thus, you may pass fields to the output mesh without using them as subdivision criteria. In than case, the allowableFieldErr will have an empty entry for those fields.
allowableFieldErr	is an array of tolerances, one for each field passed to the output. If the linearly interpolated and actual midpoint values for any field are greater than the value specified here, the member will return true.