Geom2d_Circle Class Reference

Describes a circle in the plane (2D space). A circle is defined by its radius and, as with any conic curve, is positioned in the plane with a coordinate system (gp_Ax22d object) where the origin is the center of the circle. The coordinate system is the local coordinate system of the circle. The orientation (direct or indirect) of the local coordinate system gives an explicit orientation to the circle, determining the direction in which the parameter increases along the circle. The Geom2d_Circle circle is parameterized by an angle: P(U) = O + R*std::cos(U)*XDir + R*Sin(U)*YDir where: More...

#include <Geom2d_Circle.hxx>

Inheritance diagram for Geom2d_Circle:

Public Member Functions
	Geom2d_Circle (const gp_Circ2d &C)
	Constructs a circle by conversion of the gp_Circ2d circle C.
	Geom2d_Circle (const gp_Ax2d &A, const double Radius, const bool Sense=true)
	Constructs a circle of radius Radius, whose center is the origin of axis A; A is the "X Axis" of the local coordinate system of the circle; this coordinate system is direct if Sense is true (default value) or indirect if Sense is false. Note: It is possible to create a circle where Radius is equal to 0.0. Exceptions Standard_ConstructionError if Radius is negative.
	Geom2d_Circle (const gp_Ax22d &A, const double Radius)
	Constructs a circle of radius Radius, where the coordinate system A locates the circle and defines its orientation in the plane such that:
void	SetCirc2d (const gp_Circ2d &C)
	Converts the gp_Circ2d circle C into this circle.
void	SetRadius (const double R)
gp_Circ2d	Circ2d () const
	Returns the non persistent circle from gp with the same geometric properties as <me>.
double	Radius () const
	Returns the radius of this circle.
double	ReversedParameter (const double U) const final
	Computes the parameter on the reversed circle for the point of parameter U on this circle. For a circle, the returned value is: 2.*Pi - U.
double	Eccentricity () const final
	Returns 0., which is the eccentricity of any circle.
double	FirstParameter () const final
	Returns 0.0.
double	LastParameter () const final
	Returns 2*PI.
bool	IsClosed () const final
	returns True.
bool	IsPeriodic () const final
	returns True. The period of a circle is 2.*Pi.
gp_Pnt2d	EvalD0 (const double U) const final
	Returns in P the point of parameter U. P = C + R * Cos (U) * XDir + R * Sin (U) * YDir where C is the center of the circle , XDir the XDirection and YDir the YDirection of the circle's local coordinate system.
Geom2d_Curve::ResD1	EvalD1 (const double U) const final
	Returns the point P of parameter U and the first derivative V1.
Geom2d_Curve::ResD2	EvalD2 (const double U) const final
	Returns the point P of parameter U, the first and second derivatives V1 and V2.
Geom2d_Curve::ResD3	EvalD3 (const double U) const final
	Returns the point P of parameter u, the first second and third derivatives V1 V2 and V3.
gp_Vec2d	EvalDN (const double U, const int N) const final
	For the point of parameter U of this circle, computes the vector corresponding to the Nth derivative. Exceptions: Standard_RangeError if N is less than 1.
void	Transform (const gp_Trsf2d &T) final
	Applies the transformation T to this circle.
occ::handle< Geom2d_Geometry >	Copy () const final
	Creates a new object which is a copy of this circle.
void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const final
	Dumps the content of me into the stream.
Public Member Functions inherited from Geom2d_Conic
void	SetAxis (const gp_Ax22d &theA)
	Modifies this conic, redefining its local coordinate system partially, by assigning theA as its axis.
void	SetXAxis (const gp_Ax2d &theAX)
	Assigns the origin and unit vector of axis theA to the origin of the local coordinate system of this conic and X Direction. The other unit vector of the local coordinate system of this conic is recomputed normal to theA, without changing the orientation of the local coordinate system (right-handed or left-handed).
void	SetYAxis (const gp_Ax2d &theAY)
	Assigns the origin and unit vector of axis theA to the origin of the local coordinate system of this conic and Y Direction. The other unit vector of the local coordinate system of this conic is recomputed normal to theA, without changing the orientation of the local coordinate system (right-handed or left-handed).
void	SetLocation (const gp_Pnt2d &theP)
	Modifies this conic, redefining its local coordinate system partially, by assigning theP as its origin.
gp_Ax2d	XAxis () const
	Returns the "XAxis" of the conic. This axis defines the origin of parametrization of the conic. This axis and the "Yaxis" define the local coordinate system of the conic. -C++: return const&.
gp_Ax2d	YAxis () const
	Returns the "YAxis" of the conic. The "YAxis" is perpendicular to the "Xaxis".
const gp_Pnt2d &	Location () const
	Returns the location point of the conic. For the circle, the ellipse and the hyperbola it is the center of the conic. For the parabola it is the vertex of the parabola.
const gp_Ax22d &	Position () const
	Returns the local coordinates system of the conic.
void	Reverse () override
	Reverses the direction of parameterization of <me>. The local coordinate system of the conic is modified.
GeomAbs_Shape	Continuity () const override
	Returns GeomAbs_CN which is the global continuity of any conic.
bool	IsCN (const int N) const override
	Returns True, the order of continuity of a conic is infinite.
void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const override
	Dumps the content of me into the stream.
Public Member Functions inherited from Geom2d_Curve
virtual double	TransformedParameter (const double U, const gp_Trsf2d &T) const
	Computes the parameter on the curve transformed by T for the point of parameter U on this curve. Note: this function generally returns U but it can be redefined (for example, on a line).
virtual double	ParametricTransformation (const gp_Trsf2d &T) const
	Returns the coefficient required to compute the parametric transformation of this curve when transformation T is applied. This coefficient is the ratio between the parameter of a point on this curve and the parameter of the transformed point on the new curve transformed by T. Note: this function generally returns 1. but it can be redefined (for example, on a line).
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:
virtual double	Period () const
	Returns the period of this curve. raises if the curve is not periodic.
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.
void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const override
	Dumps the content of me into the stream.
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.
Protected Attributes inherited from Geom2d_Conic
gp_Ax22d	pos

Detailed Description

Describes a circle in the plane (2D space). A circle is defined by its radius and, as with any conic curve, is positioned in the plane with a coordinate system (gp_Ax22d object) where the origin is the center of the circle. The coordinate system is the local coordinate system of the circle. The orientation (direct or indirect) of the local coordinate system gives an explicit orientation to the circle, determining the direction in which the parameter increases along the circle. The Geom2d_Circle circle is parameterized by an angle: P(U) = O + R*std::cos(U)*XDir + R*Sin(U)*YDir where:

• P is the point of parameter U,
• O, XDir and YDir are respectively the origin, "X Direction" and "Y Direction" of its local coordinate system,
• R is the radius of the circle. The "X Axis" of the local coordinate system therefore defines the origin of the parameter of the circle. The parameter is the angle with this "X Direction". A circle is a closed and periodic curve. The period is 2.*Pi and the parameter range is [ 0,2.*Pi [. See Also GCE2d_MakeCircle which provides functions for more complex circle constructions gp_Ax22d and gp_Circ2d for an equivalent, non-parameterized data structure.

Constructor & Destructor Documentation

Geom2d_Circle() [1/3]

Geom2d_Circle::Geom2d_Circle

(

const gp_Circ2d &

C

)

Constructs a circle by conversion of the gp_Circ2d circle C.

Geom2d_Circle() [2/3]

Geom2d_Circle::Geom2d_Circle	(	const gp_Ax2d &	A,
		const double	Radius,
		const bool	Sense = true )

Constructs a circle of radius Radius, whose center is the origin of axis A; A is the "X Axis" of the local coordinate system of the circle; this coordinate system is direct if Sense is true (default value) or indirect if Sense is false. Note: It is possible to create a circle where Radius is equal to 0.0. Exceptions Standard_ConstructionError if Radius is negative.

Geom2d_Circle() [3/3]

Geom2d_Circle::Geom2d_Circle	(	const gp_Ax22d &	A,
		const double	Radius )

Constructs a circle of radius Radius, where the coordinate system A locates the circle and defines its orientation in the plane such that:

• the center of the circle is the origin of A,
• the orientation (direct or indirect) of A gives the orientation of the circle.

Member Function Documentation

Circ2d()

gp_Circ2d Geom2d_Circle::Circ2d

(

)

const

Returns the non persistent circle from gp with the same geometric properties as <me>.

Copy()

occ::handle< Geom2d_Geometry > Geom2d_Circle::Copy ( ) const

finalvirtual

Creates a new object which is a copy of this circle.

Implements Geom2d_Geometry.

DumpJson()

void Geom2d_Circle::DumpJson ( Standard_OStream & theOStream, int theDepth = -1 ) const

finalvirtual

Dumps the content of me into the stream.

Reimplemented from Geom2d_Geometry.

Eccentricity()

double Geom2d_Circle::Eccentricity ( ) const

finalvirtual

Returns 0., which is the eccentricity of any circle.

Implements Geom2d_Conic.

EvalD0()

gp_Pnt2d Geom2d_Circle::EvalD0 ( const double U ) const

finalvirtual

Returns in P the point of parameter U. P = C + R * Cos (U) * XDir + R * Sin (U) * YDir where C is the center of the circle , XDir the XDirection and YDir the YDirection of the circle's local coordinate system.

Implements Geom2d_Curve.

EvalD1()

Geom2d_Curve::ResD1 Geom2d_Circle::EvalD1 ( const double U ) const

finalvirtual

Returns the point P of parameter U and the first derivative V1.

Implements Geom2d_Curve.

EvalD2()

Geom2d_Curve::ResD2 Geom2d_Circle::EvalD2 ( const double U ) const

finalvirtual

Returns the point P of parameter U, the first and second derivatives V1 and V2.

Implements Geom2d_Curve.

EvalD3()

Geom2d_Curve::ResD3 Geom2d_Circle::EvalD3 ( const double U ) const

finalvirtual

Returns the point P of parameter u, the first second and third derivatives V1 V2 and V3.

Implements Geom2d_Curve.

EvalDN()

gp_Vec2d Geom2d_Circle::EvalDN ( const double U, const int N ) const

finalvirtual

For the point of parameter U of this circle, computes the vector corresponding to the Nth derivative. Exceptions: Standard_RangeError if N is less than 1.

Implements Geom2d_Curve.

FirstParameter()

double Geom2d_Circle::FirstParameter ( ) const

finalvirtual

Returns 0.0.

Implements Geom2d_Curve.

IsClosed()

bool Geom2d_Circle::IsClosed ( ) const

finalvirtual

returns True.

Implements Geom2d_Curve.

IsPeriodic()

bool Geom2d_Circle::IsPeriodic ( ) const

finalvirtual

returns True. The period of a circle is 2.*Pi.

Implements Geom2d_Curve.

LastParameter()

double Geom2d_Circle::LastParameter ( ) const

finalvirtual

Returns 2*PI.

Implements Geom2d_Curve.

Radius()

double Geom2d_Circle::Radius

(

)

const

Returns the radius of this circle.

ReversedParameter()

double Geom2d_Circle::ReversedParameter ( const double U ) const

finalvirtual

Computes the parameter on the reversed circle for the point of parameter U on this circle. For a circle, the returned value is: 2.*Pi - U.

Implements Geom2d_Conic.

SetCirc2d()

void Geom2d_Circle::SetCirc2d

(

const gp_Circ2d &

C

)

Converts the gp_Circ2d circle C into this circle.

SetRadius()

void Geom2d_Circle::SetRadius

(

const double

R

)

Transform()

void Geom2d_Circle::Transform ( const gp_Trsf2d & T )

finalvirtual

Applies the transformation T to this circle.

Implements Geom2d_Geometry.

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

• Geom2d_Circle.hxx