BSplSLib_Cache Class Reference

A cache class for Bezier and B-spline surfaces. More...

#include <BSplSLib_Cache.hxx>

Inheritance diagram for BSplSLib_Cache:

Public Member Functions
	BSplSLib_Cache (const Standard_Integer &theDegreeU, const Standard_Boolean &thePeriodicU, const TColStd_Array1OfReal &theFlatKnotsU, const Standard_Integer &theDegreeV, const Standard_Boolean &thePeriodicV, const TColStd_Array1OfReal &theFlatKnotsV, const TColStd_Array2OfReal *theWeights=NULL)
	Constructor for caching of the span for the surface.
Standard_Boolean	IsCacheValid (Standard_Real theParameterU, Standard_Real theParameterV) const
	Verifies validity of the cache using parameters of the point.
void	BuildCache (const Standard_Real &theParameterU, const Standard_Real &theParameterV, const TColStd_Array1OfReal &theFlatKnotsU, const TColStd_Array1OfReal &theFlatKnotsV, const TColgp_Array2OfPnt &thePoles, const TColStd_Array2OfReal *theWeights=NULL)
	Recomputes the cache data. Does not verify validity of the cache.
void	D0 (const Standard_Real &theU, const Standard_Real &theV, gp_Pnt &thePoint) const
	Calculates the point on the surface for specified parameters.
void	D1 (const Standard_Real &theU, const Standard_Real &theV, gp_Pnt &thePoint, gp_Vec &theTangentU, gp_Vec &theTangentV) const
	Calculates the point on the surface and its first derivative.
void	D2 (const Standard_Real &theU, const Standard_Real &theV, gp_Pnt &thePoint, gp_Vec &theTangentU, gp_Vec &theTangentV, gp_Vec &theCurvatureU, gp_Vec &theCurvatureV, gp_Vec &theCurvatureUV) const
	Calculates the point on the surface and derivatives till second order.
Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.
	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.
Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.
virtual	~Standard_Transient ()
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
Standard_Boolean	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
Standard_Boolean	IsInstance (const Standard_CString theTypeName) const
	Returns a true value if this is an instance of TypeName.
Standard_Boolean	IsKind (const opencascade::handle< Standard_Type > &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Boolean	IsKind (const Standard_CString theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.
Standard_Integer	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object.
Standard_Integer	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value.
virtual void	Delete () const
	Memory deallocator for transient classes.

Additional Inherited Members
typedef void	base_type
	Returns a type descriptor about this object.
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.
static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.

Detailed Description

A cache class for Bezier and B-spline surfaces.

Defines all data, that can be cached on a span of the surface. The data should be recalculated in going from span to span.

Constructor & Destructor Documentation

BSplSLib_Cache()

BSplSLib_Cache::BSplSLib_Cache	(	const Standard_Integer &	theDegreeU,
		const Standard_Boolean &	thePeriodicU,
		const TColStd_Array1OfReal &	theFlatKnotsU,
		const Standard_Integer &	theDegreeV,
		const Standard_Boolean &	thePeriodicV,
		const TColStd_Array1OfReal &	theFlatKnotsV,
		const TColStd_Array2OfReal *	theWeights = NULL )

Constructor for caching of the span for the surface.

Parameters

theDegreeU	degree along the first parameter (U) of the surface
thePeriodicU	identify the surface is periodical along U axis
theFlatKnotsU	knots of the surface (with repetition) along U axis
theDegreeV	degree along the second parameter (V) of the surface
thePeriodicV	identify the surface is periodical along V axis
theFlatKnotsV	knots of the surface (with repetition) along V axis
theWeights	array of weights of corresponding poles

Member Function Documentation

BuildCache()

void BSplSLib_Cache::BuildCache	(	const Standard_Real &	theParameterU,
		const Standard_Real &	theParameterV,
		const TColStd_Array1OfReal &	theFlatKnotsU,
		const TColStd_Array1OfReal &	theFlatKnotsV,
		const TColgp_Array2OfPnt &	thePoles,
		const TColStd_Array2OfReal *	theWeights = NULL )

Recomputes the cache data. Does not verify validity of the cache.

Parameters

theParameterU	the parametric value on the U axis to identify the span
theParameterV	the parametric value on the V axis to identify the span
theDegreeU	degree along U axis
thePeriodicU	identify whether the surface is periodic along U axis
theFlatKnotsU	flat knots of the surface along U axis
theDegreeV	degree along V axis
thePeriodicV	identify whether the surface is periodic along V axis
theFlatKnotsV	flat knots of the surface along V axis
thePoles	array of poles of the surface
theWeights	array of weights of corresponding poles

D0()

void BSplSLib_Cache::D0	(	const Standard_Real &	theU,
		const Standard_Real &	theV,
		gp_Pnt &	thePoint ) const

Calculates the point on the surface for specified parameters.

Parameters

[in]	theU	first parameter for calculation of the value
[in]	theV	second parameter for calculation of the value
[out]	thePoint	the result of calculation (the point on the surface)

D1()

void BSplSLib_Cache::D1	(	const Standard_Real &	theU,
		const Standard_Real &	theV,
		gp_Pnt &	thePoint,
		gp_Vec &	theTangentU,
		gp_Vec &	theTangentV ) const

Calculates the point on the surface and its first derivative.

Parameters

[in]	theU	first parameter of calculation of the value
[in]	theV	second parameter of calculation of the value
[out]	thePoint	the result of calculation (the point on the surface)
[out]	theTangentU	tangent vector along U axis in the calculated point
[out]	theTangentV	tangent vector along V axis in the calculated point

D2()

void BSplSLib_Cache::D2	(	const Standard_Real &	theU,
		const Standard_Real &	theV,
		gp_Pnt &	thePoint,
		gp_Vec &	theTangentU,
		gp_Vec &	theTangentV,
		gp_Vec &	theCurvatureU,
		gp_Vec &	theCurvatureV,
		gp_Vec &	theCurvatureUV ) const

Calculates the point on the surface and derivatives till second order.

Parameters

[in]	theU	first parameter of calculation of the value
[in]	theV	second parameter of calculation of the value
[out]	thePoint	the result of calculation (the point on the surface)
[out]	theTangentU	tangent vector along U axis in the calculated point
[out]	theTangentV	tangent vector along V axis in the calculated point
[out]	theCurvatureU	curvature vector (2nd derivative on U) along U axis
[out]	theCurvatureV	curvature vector (2nd derivative on V) along V axis
[out]	theCurvatureUV	2nd mixed derivative on U anv V

IsCacheValid()

Standard_Boolean BSplSLib_Cache::IsCacheValid	(	Standard_Real	theParameterU,
		Standard_Real	theParameterV ) const

Verifies validity of the cache using parameters of the point.

Parameters

theParameterU	first parameter of the point placed in the span
theParameterV	second parameter of the point placed in the span

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

• BSplSLib_Cache.hxx