Template utility functions for CLProps curve local property computation. Provides access policies (DirectAccess, ToolAccess) and shared algorithms for evaluating derivatives, tangents, curvature, normals, and centres of curvature. More...

Data Structures
struct	DirectAccess
	Direct access policy: calls D0/D1/D2/D3 methods on the curve object. Works with occ::handle<T> and by-value curve types. More...

struct	ToolAccess
	Tool-based access policy: delegates to static Tool methods. Used for HLRBRep types where Tool class provides the interface. More...

Functions
template<typename T >
T &	Deref (T &theObj)
	Dereference by-value or reference types (identity).

template<typename T >
T &	Deref (occ::handle< T > &theHandle)
	Dereference occ::handle types.

template<typename T >
const T &	Deref (const occ::handle< T > &theHandle)
	Dereference const occ::handle types.

template<typename Access , typename Curve , typename Pnt , typename Vec >
void	EvalDerivatives (Curve &theCurve, double theU, int theOrder, Pnt &thePnt, Vec *theDerivArr)
	Evaluate curve derivatives at parameter theU up to specified order.

template<typename Access , typename Curve , typename Vec , typename Pnt , typename Dir >
void	ComputeTangent (Curve &theCurve, double theU, const Vec *theDerivArr, const Pnt &, int theSigOrder, Dir &theDir)
	Compute tangent direction with sign correction for higher-order derivatives. When the first significant derivative has order > 1, the sign of the tangent is determined by comparing with the chord direction near the point.

template<typename Vec >
double	ComputeCurvature (const Vec &theD1, const Vec &theD2, double theTolSq)
	Compute curvature from first and second derivatives. Returns \|D1 x D2\| / \|D1\|^3, or 0 if derivatives are collinear or D2 is null.

template<typename Vec , typename Dir >
void	ComputeNormal (const Vec &theD1, const Vec &theD2, Dir &theDir)
	Compute normal direction from first and second derivatives. Normal = D2(D1D1) - D1(D1D2), using the vector triple product identity.

template<typename Vec , typename Pnt >
void	ComputeCentreOfCurvature (const Pnt &thePnt, const Vec &theD1, const Vec &theD2, double theCurvature, Pnt &theCentre)
	Compute centre of curvature from point, derivatives, and curvature. Centre = Point + Normal / Curvature.

template<typename Access , typename Curve , typename Pnt , typename Vec >
void	SetParameter (Curve &theCurve, double theU, double &theStoredU, int theDerOrder, Pnt &thePnt, Vec *theDerivArr, LProp_Status &theTanStatus)
	SetParameter wrapper: sets parameter, evaluates derivatives, resets tangent status.

template<typename Access , typename Curve , typename Pnt , typename Vec >
const Vec &	EnsureDeriv (Curve &theCurve, double theU, int &theDerOrder, int theRequired, Pnt &thePnt, Vec *theDerivArr)
	Ensure derivatives up to the required order are computed.

template<typename Vec , typename Props >
bool	IsTangentDefined (Props &theProps, int theCN, double theLinTol, int &theSigOrder, LProp_Status &theTanStatus)
	IsTangentDefined: searches for first non-null derivative. Calls theProps.D1(), theProps.D2(), theProps.D3() to upgrade derivatives as needed.

template<typename Access , typename Props , typename Curve , typename Vec , typename Pnt , typename Dir >
void	Tangent (Props &theProps, Curve &theCurve, double theU, const Vec *theDerivArr, const Pnt &theRefPnt, const int &theSigOrder, Dir &theDir)
	Tangent: checks IsTangentDefined, then computes tangent direction.

template<typename Props , typename Vec >
double	Curvature (Props &theProps, const Vec &theD1, const Vec &theD2, double theLinTol, const int &theSigOrder, double &theCurvature)
	Curvature: checks IsTangentDefined, returns RealLast if higher-order, else computes.

template<typename Props , typename Vec , typename Dir >
void	Normal (Props &theProps, const Vec &theD1, const Vec &theD2, double theLinTol, Dir &theDir)
	Normal: checks curvature, then computes normal direction.

template<typename Props , typename Vec , typename Pnt >
void	CentreOfCurvature (Props &theProps, const Pnt &thePnt, const Vec &theD1, const Vec &theD2, double theLinTol, double &theCurvature, Pnt &theCentre)
	CentreOfCurvature: checks curvature, then computes centre.

Detailed Description

Template utility functions for CLProps curve local property computation. Provides access policies (DirectAccess, ToolAccess) and shared algorithms for evaluating derivatives, tangents, curvature, normals, and centres of curvature.

Function Documentation

◆ CentreOfCurvature()

template<typename Props , typename Vec , typename Pnt >

void LProp_CurveUtils::CentreOfCurvature	(	Props &	theProps,
		const Pnt &	thePnt,
		const Vec &	theD1,
		const Vec &	theD2,
		double	theLinTol,
		double &	theCurvature,
		Pnt &	theCentre )

CentreOfCurvature: checks curvature, then computes centre.

Parameters

[in,out]	theProps	CLProps object
[in]	thePnt	current point
[in]	theD1	first derivative
[in]	theD2	second derivative
[in]	theLinTol	linear tolerance
[in,out]	theCurvature	curvature value field
[out]	theCentre	computed centre of curvature

◆ ComputeCentreOfCurvature()

template<typename Vec , typename Pnt >

void LProp_CurveUtils::ComputeCentreOfCurvature	(	const Pnt &	thePnt,
		const Vec &	theD1,
		const Vec &	theD2,
		double	theCurvature,
		Pnt &	theCentre )

Compute centre of curvature from point, derivatives, and curvature. Centre = Point + Normal / Curvature.

Parameters

[in]	thePnt	current point
[in]	theD1	first derivative
[in]	theD2	second derivative
[in]	theCurvature	curvature value (must be non-zero)
[out]	theCentre	computed centre of curvature

◆ ComputeCurvature()

template<typename Vec >

double LProp_CurveUtils::ComputeCurvature	(	const Vec &	theD1,
		const Vec &	theD2,
		double	theTolSq )

Compute curvature from first and second derivatives. Returns |D1 x D2| / |D1|^3, or 0 if derivatives are collinear or D2 is null.

Parameters

[in]	theD1	first derivative
[in]	theD2	second derivative
[in]	theTolSq	squared linear tolerance

Returns: curvature value

◆ ComputeNormal()

template<typename Vec , typename Dir >

void LProp_CurveUtils::ComputeNormal	(	const Vec &	theD1,
		const Vec &	theD2,
		Dir &	theDir )

Compute normal direction from first and second derivatives. Normal = D2*(D1*D1) - D1*(D1*D2), using the vector triple product identity.

Parameters

[in]	theD1	first derivative
[in]	theD2	second derivative
[out]	theDir	computed normal direction

◆ ComputeTangent()

template<typename Access , typename Curve , typename Vec , typename Pnt , typename Dir >

void LProp_CurveUtils::ComputeTangent	(	Curve &	theCurve,
		double	theU,
		const Vec *	theDerivArr,
		const Pnt &	,
		int	theSigOrder,
		Dir &	theDir )

Compute tangent direction with sign correction for higher-order derivatives. When the first significant derivative has order > 1, the sign of the tangent is determined by comparing with the chord direction near the point.

Parameters

[in,out]	theCurve	curve object
[in]	theU	current parameter
[in]	theDerivArr	derivative array
[in]	theRefPnt	reference point (used only for type deduction)
[in]	theSigOrder	order of first significant derivative
[out]	theDir	computed tangent direction

◆ Curvature()

template<typename Props , typename Vec >

double LProp_CurveUtils::Curvature	(	Props &	theProps,
		const Vec &	theD1,
		const Vec &	theD2,
		double	theLinTol,
		const int &	theSigOrder,
		double &	theCurvature )

Curvature: checks IsTangentDefined, returns RealLast if higher-order, else computes.

Parameters

[in,out]	theProps	CLProps object
[in]	theD1	first derivative
[in]	theD2	second derivative
[in]	theLinTol	linear tolerance
[in]	theSigOrder	order of first significant derivative
[out]	theCurvature	curvature value field

Returns: computed curvature

◆ Deref() [1/3]

template<typename T >

const T & LProp_CurveUtils::Deref ( const occ::handle< T > & theHandle )

Dereference const occ::handle types.

◆ Deref() [2/3]

template<typename T >

T & LProp_CurveUtils::Deref ( occ::handle< T > & theHandle )

Dereference occ::handle types.

◆ Deref() [3/3]

template<typename T >

T & LProp_CurveUtils::Deref ( T & theObj )

Dereference by-value or reference types (identity).

◆ EnsureDeriv()

template<typename Access , typename Curve , typename Pnt , typename Vec >

const Vec & LProp_CurveUtils::EnsureDeriv	(	Curve &	theCurve,
		double	theU,
		int &	theDerOrder,
		int	theRequired,
		Pnt &	thePnt,
		Vec *	theDerivArr )

Ensure derivatives up to the required order are computed.

Parameters

[in,out]	theCurve	curve object
[in]	theU	parameter value
[in,out]	theDerOrder	current derivative order (upgraded if needed)
[in]	theRequired	required derivative order
[out]	thePnt	evaluated point
[out]	theDerivArr	derivative array

Returns: reference to theDerivArr[theRequired-1]

◆ EvalDerivatives()

template<typename Access , typename Curve , typename Pnt , typename Vec >

void LProp_CurveUtils::EvalDerivatives	(	Curve &	theCurve,
		double	theU,
		int	theOrder,
		Pnt &	thePnt,
		Vec *	theDerivArr )

Evaluate curve derivatives at parameter theU up to specified order.

Parameters

[in,out]	theCurve	curve object
[in]	theU	parameter value
[in]	theOrder	maximum derivative order (0-3)
[out]	thePnt	evaluated point
[out]	theDerivArr	derivative array (size >= theOrder)

◆ IsTangentDefined()

template<typename Vec , typename Props >

bool LProp_CurveUtils::IsTangentDefined	(	Props &	theProps,
		int	theCN,
		double	theLinTol,
		int &	theSigOrder,
		LProp_Status &	theTanStatus )

IsTangentDefined: searches for first non-null derivative. Calls theProps.D1(), theProps.D2(), theProps.D3() to upgrade derivatives as needed.

Parameters

[in,out]	theProps	CLProps object
[in]	theCN	continuity order
[in]	theLinTol	linear tolerance
[out]	theSigOrder	order of first significant derivative
[in,out]	theTanStatus	tangent status field

Returns: true if tangent is defined

◆ Normal()

template<typename Props , typename Vec , typename Dir >

void LProp_CurveUtils::Normal	(	Props &	theProps,
		const Vec &	theD1,
		const Vec &	theD2,
		double	theLinTol,
		Dir &	theDir )

Normal: checks curvature, then computes normal direction.

Parameters

[in,out]	theProps	CLProps object
[in]	theD1	first derivative
[in]	theD2	second derivative
[in]	theLinTol	linear tolerance
[out]	theDir	computed normal direction

◆ SetParameter()

template<typename Access , typename Curve , typename Pnt , typename Vec >

void LProp_CurveUtils::SetParameter	(	Curve &	theCurve,
		double	theU,
		double &	theStoredU,
		int	theDerOrder,
		Pnt &	thePnt,
		Vec *	theDerivArr,
		LProp_Status &	theTanStatus )

SetParameter wrapper: sets parameter, evaluates derivatives, resets tangent status.

Parameters

[in,out]	theCurve	curve object
[in]	theU	parameter value
[out]	theStoredU	stored parameter field
[in]	theDerOrder	current derivative order
[out]	thePnt	evaluated point
[out]	theDerivArr	derivative array
[out]	theTanStatus	tangent status field

◆ Tangent()

template<typename Access , typename Props , typename Curve , typename Vec , typename Pnt , typename Dir >

void LProp_CurveUtils::Tangent	(	Props &	theProps,
		Curve &	theCurve,
		double	theU,
		const Vec *	theDerivArr,
		const Pnt &	theRefPnt,
		const int &	theSigOrder,
		Dir &	theDir )

Tangent: checks IsTangentDefined, then computes tangent direction.

Parameters

[in,out]	theProps	CLProps object
[in,out]	theCurve	curve object
[in]	theU	current parameter
[in]	theDerivArr	derivative array
[in]	theRefPnt	reference point (for type deduction)
[in]	theSigOrder	order of first significant derivative
[out]	theDir	computed tangent direction

Data Structures

Functions

Detailed Description

Function Documentation

◆ CentreOfCurvature()

◆ ComputeCentreOfCurvature()

◆ ComputeCurvature()

◆ ComputeNormal()

◆ ComputeTangent()

◆ Curvature()

◆ Deref() [1/3]

◆ Deref() [2/3]

◆ Deref() [3/3]

◆ EnsureDeriv()

◆ EvalDerivatives()

◆ IsTangentDefined()

◆ Normal()

◆ SetParameter()

◆ Tangent()