Geom2d_TrimmedCurve Class Reference

Defines a portion of a curve limited by two values of parameters inside the parametric domain of the curve. The trimmed curve is defined by: More...

#include <Geom2d_TrimmedCurve.hxx>

Inheritance diagram for Geom2d_TrimmedCurve:

Public Member Functions
	Geom2d_TrimmedCurve (const occ::handle< Geom2d_Curve > &C, const double U1, const double U2, const bool Sense=true, const bool theAdjustPeriodic=true)
	Creates a trimmed curve from the basis curve C limited between U1 and U2.
void	Reverse () final
	Changes the direction of parametrization of <me>. The first and the last parametric values are modified. The "StartPoint" of the initial curve becomes the "EndPoint" of the reversed curve and the "EndPoint" of the initial curve becomes the "StartPoint" of the reversed curve. Example - If the trimmed curve is defined by:
double	ReversedParameter (const double U) const final
	Returns the parameter on the reversed curve for the point of parameter U on <me>.
void	SetTrim (const double U1, const double U2, const bool Sense=true, const bool theAdjustPeriodic=true)
	Changes this trimmed curve, by redefining the parameter values U1 and U2, which limit its basis curve. Note: If the basis curve is periodic, the trimmed curve has the same orientation as the basis curve if Sense is true (default value) or the opposite orientation if Sense is false. Warning If the basis curve is periodic and theAdjustPeriodic is True, the bounds of the trimmed curve may be different from U1 and U2 if the parametric origin of the basis curve is within the arc of the trimmed curve. In this case, the modified parameter will be equal to U1 or U2 plus or minus the period. If theAdjustPeriodic is False, parameters U1 and U2 will stay unchanged. Exceptions Standard_ConstructionError if:
occ::handle< Geom2d_Curve >	BasisCurve () const
	Returns the basis curve. Warning This function does not return a constant reference. Consequently, any modification of the returned value directly modifies the trimmed curve.
GeomAbs_Shape	Continuity () const final
	Returns the global continuity of the basis curve of this trimmed curve. C0 : only geometric continuity, C1 : continuity of the first derivative all along the Curve, C2 : continuity of the second derivative all along the Curve, C3 : continuity of the third derivative all along the Curve, CN : the order of continuity is infinite.
bool	IsCN (const int N) const final
	— Purpose Returns True if the order of continuity of the trimmed curve is N. A trimmed curve is at least "C0" continuous. Warnings : The continuity of the trimmed curve can be greater than the continuity of the basis curve because you consider only a part of the basis curve. Raised if N < 0.
gp_Pnt2d	EndPoint () const final
	Returns the end point of <me>. This point is the evaluation of the curve for the "LastParameter".
double	FirstParameter () const final
	Returns the value of the first parameter of <me>. The first parameter is the parameter of the "StartPoint" of the trimmed curve.
bool	IsClosed () const final
	Returns TRUE if the basis curve is periodic and the trim spans exactly one full period, or if the distance between the StartPoint and the EndPoint is within computational precision.
bool	IsPeriodic () const final
	Returns TRUE if the basis curve is periodic and the trim spans exactly one full period. Returns FALSE otherwise.
double	Period () const final
	Returns the period of the basis curve of this trimmed curve. Exceptions Standard_NoSuchObject if the basis curve is not periodic.
double	LastParameter () const final
	Returns the value of the last parameter of <me>. The last parameter is the parameter of the "EndPoint" of the trimmed curve.
gp_Pnt2d	StartPoint () const final
	Returns the start point of <me>. This point is the evaluation of the curve from the "FirstParameter". value and derivatives Warnings : The returned derivatives have the same orientation as the derivatives of the basis curve.
gp_Pnt2d	EvalD0 (const double U) const final
	If the basis curve is an OffsetCurve sometimes it is not possible to do the evaluation of the curve at the parameter U (see class OffsetCurve).
Geom2d_Curve::ResD1	EvalD1 (const double U) const final
	Raised if the continuity of the curve is not C1.
Geom2d_Curve::ResD2	EvalD2 (const double U) const final
	Raised if the continuity of the curve is not C2.
Geom2d_Curve::ResD3	EvalD3 (const double U) const final
	Raised if the continuity of the curve is not C3.
gp_Vec2d	EvalDN (const double U, const int N) const final
	For the point of parameter U of this trimmed curve, computes the vector corresponding to the Nth derivative. Warning The returned derivative vector has the same orientation as the derivative vector of the basis curve, even if the trimmed curve does not have the same orientation as the basis curve. Exceptions Standard_RangeError if N is less than 1. geometric transformations.
void	Transform (const gp_Trsf2d &T) final
	Applies the transformation T to this trimmed curve. Warning The basis curve is also modified.
double	TransformedParameter (const double U, const gp_Trsf2d &T) const final
	Returns the parameter on the transformed curve for the transform of the point of parameter U on <me>.
double	ParametricTransformation (const gp_Trsf2d &T) const final
	Returns a coefficient to compute the parameter on the transformed curve for the transform of the point on <me>.
occ::handle< Geom2d_Geometry >	Copy () const final
	Creates a new object, which is a copy of this trimmed curve.
void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const final
	Dumps the content of me into the stream.
Public Member Functions inherited from Geom2d_Curve
occ::handle< Geom2d_Curve >	Reversed () const
	Creates a reversed duplicate Changes the orientation of this curve. The first and last parameters are not changed, but the parametric direction of the curve is reversed. If the curve is bounded:
void	D0 (const double U, gp_Pnt2d &P) const
	Returns in P the point of parameter U.
void	D1 (const double U, gp_Pnt2d &P, gp_Vec2d &V1) const
	Returns the point P of parameter U and the first derivative V1.
void	D2 (const double U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2) const
	Returns the point P of parameter U, the first and second derivatives V1 and V2.
void	D3 (const double U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2, gp_Vec2d &V3) const
	Returns the point P of parameter U, the first, the second and the third derivative.
gp_Vec2d	DN (const double U, const int N) const
	Computes the Nth derivative vector.
gp_Pnt2d	Value (const double U) const
	Computes the point of parameter U on <me>. Implemented with D0.
Public Member Functions inherited from Geom2d_Geometry
void	Mirror (const gp_Pnt2d &P)
	Performs the symmetrical transformation of a Geometry with respect to the point P which is the center of the symmetry and assigns the result to this geometric object.
void	Mirror (const gp_Ax2d &A)
	Performs the symmetrical transformation of a Geometry with respect to an axis placement which is the axis of the symmetry.
void	Rotate (const gp_Pnt2d &P, const double Ang)
	Rotates a Geometry. P is the center of the rotation. Ang is the angular value of the rotation in radians.
void	Scale (const gp_Pnt2d &P, const double S)
	Scales a Geometry. S is the scaling value.
void	Translate (const gp_Vec2d &V)
	Translates a Geometry. V is the vector of the translation.
void	Translate (const gp_Pnt2d &P1, const gp_Pnt2d &P2)
	Translates a Geometry from the point P1 to the point P2.
occ::handle< Geom2d_Geometry >	Mirrored (const gp_Pnt2d &P) const
occ::handle< Geom2d_Geometry >	Mirrored (const gp_Ax2d &A) const
occ::handle< Geom2d_Geometry >	Rotated (const gp_Pnt2d &P, const double Ang) const
occ::handle< Geom2d_Geometry >	Scaled (const gp_Pnt2d &P, const double S) const
occ::handle< Geom2d_Geometry >	Transformed (const gp_Trsf2d &T) const
occ::handle< Geom2d_Geometry >	Translated (const gp_Vec2d &V) const
occ::handle< Geom2d_Geometry >	Translated (const gp_Pnt2d &P1, const gp_Pnt2d &P2) const
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 ()=default
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
bool	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
bool	IsInstance (const char *const theTypeName) const
	Returns a true value if this is an instance of TypeName.
bool	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.
bool	IsKind (const char *const 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.
int	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object. Uses relaxed memory ordering since incrementing only requires atomicity, not synchronization with other memory operations.
int	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value. Uses release ordering for the decrement to ensure all writes to the object are visible before the count reaches zero. An acquire fence is added only when the count reaches zero, ensuring proper synchronization before deletion. This is more efficient than using acq_rel for every decrement.
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

Defines a portion of a curve limited by two values of parameters inside the parametric domain of the curve. The trimmed curve is defined by:

• the basis curve, and
• the two parameter values which limit it. The trimmed curve can either have the same orientation as the basis curve or the opposite orientation.

Constructor & Destructor Documentation

Geom2d_TrimmedCurve()

Geom2d_TrimmedCurve::Geom2d_TrimmedCurve	(	const occ::handle< Geom2d_Curve > &	C,
		const double	U1,
		const double	U2,
		const bool	Sense = true,
		const bool	theAdjustPeriodic = true )

Creates a trimmed curve from the basis curve C limited between U1 and U2.

. U1 can be greater or lower than U2. . The returned curve is oriented from U1 to U2. . If the basis curve C is periodic there is an ambiguity because two parts are available. In this case by default the trimmed curve has the same orientation as the basis curve (Sense = True). If Sense = False then the orientation of the trimmed curve is opposite to the orientation of the basis curve C. If the curve is closed but not periodic it is not possible to keep the part of the curve including the junction point (except if the junction point is at the beginning or at the end of the trimmed curve) because you could lose the fundamental characteristics of the basis curve which are used for example to compute the derivatives of the trimmed curve. So for a closed curve the rules are the same as for a open curve. Warnings : In this package the entities are not shared. The TrimmedCurve is built with a copy of the curve C. So when C is modified the TrimmedCurve is not modified Warnings : If is periodic and <theAdjustPeriodic> is True, parametrics bounds of the TrimmedCurve, can be different to [<U1>;<U2>}, if <U1> or <U2> are not in the principal period. Include : For more explanation see the scheme given with this class. Raises ConstructionError the C is not periodic and U1 or U2 are out of the bounds of C. Raised if U1 = U2.

Member Function Documentation

BasisCurve()

occ::handle< Geom2d_Curve > Geom2d_TrimmedCurve::BasisCurve

(

)

const

Returns the basis curve. Warning This function does not return a constant reference. Consequently, any modification of the returned value directly modifies the trimmed curve.

Continuity()

GeomAbs_Shape Geom2d_TrimmedCurve::Continuity ( ) const

finalvirtual

Returns the global continuity of the basis curve of this trimmed curve. C0 : only geometric continuity, C1 : continuity of the first derivative all along the Curve, C2 : continuity of the second derivative all along the Curve, C3 : continuity of the third derivative all along the Curve, CN : the order of continuity is infinite.

Implements Geom2d_Curve.

Copy()

occ::handle< Geom2d_Geometry > Geom2d_TrimmedCurve::Copy ( ) const

finalvirtual

Creates a new object, which is a copy of this trimmed curve.

Implements Geom2d_Geometry.

DumpJson()

void Geom2d_TrimmedCurve::DumpJson ( Standard_OStream & theOStream, int theDepth = -1 ) const

finalvirtual

Dumps the content of me into the stream.

Reimplemented from Geom2d_BoundedCurve.

EndPoint()

gp_Pnt2d Geom2d_TrimmedCurve::EndPoint ( ) const

finalvirtual

Returns the end point of <me>. This point is the evaluation of the curve for the "LastParameter".

Implements Geom2d_BoundedCurve.

EvalD0()

gp_Pnt2d Geom2d_TrimmedCurve::EvalD0 ( const double U ) const

finalvirtual

If the basis curve is an OffsetCurve sometimes it is not possible to do the evaluation of the curve at the parameter U (see class OffsetCurve).

Implements Geom2d_Curve.

EvalD1()

Geom2d_Curve::ResD1 Geom2d_TrimmedCurve::EvalD1 ( const double U ) const

finalvirtual

Raised if the continuity of the curve is not C1.

Implements Geom2d_Curve.

EvalD2()

Geom2d_Curve::ResD2 Geom2d_TrimmedCurve::EvalD2 ( const double U ) const

finalvirtual

Raised if the continuity of the curve is not C2.

Implements Geom2d_Curve.

EvalD3()

Geom2d_Curve::ResD3 Geom2d_TrimmedCurve::EvalD3 ( const double U ) const

finalvirtual

Raised if the continuity of the curve is not C3.

Implements Geom2d_Curve.

EvalDN()

gp_Vec2d Geom2d_TrimmedCurve::EvalDN ( const double U, const int N ) const

finalvirtual

For the point of parameter U of this trimmed curve, computes the vector corresponding to the Nth derivative. Warning The returned derivative vector has the same orientation as the derivative vector of the basis curve, even if the trimmed curve does not have the same orientation as the basis curve. Exceptions Standard_RangeError if N is less than 1. geometric transformations.

Implements Geom2d_Curve.

FirstParameter()

double Geom2d_TrimmedCurve::FirstParameter ( ) const

finalvirtual

Returns the value of the first parameter of <me>. The first parameter is the parameter of the "StartPoint" of the trimmed curve.

Implements Geom2d_Curve.

IsClosed()

bool Geom2d_TrimmedCurve::IsClosed ( ) const

finalvirtual

Returns TRUE if the basis curve is periodic and the trim spans exactly one full period, or if the distance between the StartPoint and the EndPoint is within computational precision.

Implements Geom2d_Curve.

IsCN()

bool Geom2d_TrimmedCurve::IsCN ( const int N ) const

finalvirtual

— Purpose Returns True if the order of continuity of the trimmed curve is N. A trimmed curve is at least "C0" continuous. Warnings : The continuity of the trimmed curve can be greater than the continuity of the basis curve because you consider only a part of the basis curve. Raised if N < 0.

Implements Geom2d_Curve.

IsPeriodic()

bool Geom2d_TrimmedCurve::IsPeriodic ( ) const

finalvirtual

Returns TRUE if the basis curve is periodic and the trim spans exactly one full period. Returns FALSE otherwise.

Implements Geom2d_Curve.

LastParameter()

double Geom2d_TrimmedCurve::LastParameter ( ) const

finalvirtual

Returns the value of the last parameter of <me>. The last parameter is the parameter of the "EndPoint" of the trimmed curve.

Implements Geom2d_Curve.

ParametricTransformation()

double Geom2d_TrimmedCurve::ParametricTransformation ( const gp_Trsf2d & T ) const

finalvirtual

Returns a coefficient to compute the parameter on the transformed curve for the transform of the point on <me>.

Transformed(T)->Value(U * ParametricTransformation(T))

is the same point as

Value(U).Transformed(T)

This methods calls the basis curve method.

Reimplemented from Geom2d_Curve.

Period()

double Geom2d_TrimmedCurve::Period ( ) const

finalvirtual

Returns the period of the basis curve of this trimmed curve. Exceptions Standard_NoSuchObject if the basis curve is not periodic.

Reimplemented from Geom2d_Curve.

Reverse()

void Geom2d_TrimmedCurve::Reverse ( )

finalvirtual

Changes the direction of parametrization of <me>. The first and the last parametric values are modified. The "StartPoint" of the initial curve becomes the "EndPoint" of the reversed curve and the "EndPoint" of the initial curve becomes the "StartPoint" of the reversed curve. Example - If the trimmed curve is defined by:

• a basis curve whose parameter range is [ 0.,1. ], and
• the two trim values U1 (first parameter) and U2 (last parameter), the reversed trimmed curve is defined by:
• the reversed basis curve, whose parameter range is still [ 0.,1. ], and
• the two trim values 1. - U2 (first parameter) and 1. - U1 (last parameter).

Implements Geom2d_Curve.

ReversedParameter()

double Geom2d_TrimmedCurve::ReversedParameter ( const double U ) const

finalvirtual

Returns the parameter on the reversed curve for the point of parameter U on <me>.

returns UFirst + ULast - U

Implements Geom2d_Curve.

SetTrim()

void Geom2d_TrimmedCurve::SetTrim	(	const double	U1,
		const double	U2,
		const bool	Sense = true,
		const bool	theAdjustPeriodic = true )

Changes this trimmed curve, by redefining the parameter values U1 and U2, which limit its basis curve. Note: If the basis curve is periodic, the trimmed curve has the same orientation as the basis curve if Sense is true (default value) or the opposite orientation if Sense is false. Warning If the basis curve is periodic and theAdjustPeriodic is True, the bounds of the trimmed curve may be different from U1 and U2 if the parametric origin of the basis curve is within the arc of the trimmed curve. In this case, the modified parameter will be equal to U1 or U2 plus or minus the period. If theAdjustPeriodic is False, parameters U1 and U2 will stay unchanged. Exceptions Standard_ConstructionError if:

• the basis curve is not periodic, and either U1 or U2 are outside the bounds of the basis curve, or
• U1 is equal to U2.

StartPoint()

gp_Pnt2d Geom2d_TrimmedCurve::StartPoint ( ) const

finalvirtual

Returns the start point of <me>. This point is the evaluation of the curve from the "FirstParameter". value and derivatives Warnings : The returned derivatives have the same orientation as the derivatives of the basis curve.

Implements Geom2d_BoundedCurve.

Transform()

void Geom2d_TrimmedCurve::Transform ( const gp_Trsf2d & T )

finalvirtual

Applies the transformation T to this trimmed curve. Warning The basis curve is also modified.

Implements Geom2d_Geometry.

TransformedParameter()

double Geom2d_TrimmedCurve::TransformedParameter ( const double U, const gp_Trsf2d & T ) const

finalvirtual

Returns the parameter on the transformed curve for the transform of the point of parameter U on <me>.

me->Transformed(T)->Value(me->TransformedParameter(U,T))

is the same point as

me->Value(U).Transformed(T)

This methods calls the basis curve method.

Reimplemented from Geom2d_Curve.

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

• Geom2d_TrimmedCurve.hxx