Describes an ellipse in 3D space. An ellipse is defined by its major and minor radii and, as with any conic curve, is positioned in space with a right-handed coordinate system (gp_Ax2 object) where: More...

#include <Geom_Ellipse.hxx>

Inheritance diagram for Geom_Ellipse:

[legend]

Public Member Functions
	Geom_Ellipse (const gp_Elips &E)
	Constructs an ellipse by conversion of the gp_Elips ellipse E.

	Geom_Ellipse (const gp_Ax2 &A2, const double MajorRadius, const double MinorRadius)
	Constructs an ellipse defined by its major and minor radii, MajorRadius and MinorRadius, where A2 locates the ellipse and defines its orientation in 3D space such that:

void	SetElips (const gp_Elips &E)
	Converts the gp_Elips ellipse E into this ellipse.

void	SetMajorRadius (const double MajorRadius)
	Assigns a value to the major radius of this ellipse. ConstructionError raised if MajorRadius < MinorRadius.

void	SetMinorRadius (const double MinorRadius)
	Assigns a value to the minor radius of this ellipse. ConstructionError raised if MajorRadius < MinorRadius or if MinorRadius < 0.

gp_Elips	Elips () const
	returns the non transient ellipse from gp with the same

double	ReversedParameter (const double U) const final
	Computes the parameter on the reversed ellipse for the point of parameter U on this ellipse. For an ellipse, the returned value is: 2.*Pi - U.

gp_Ax1	Directrix1 () const
	This directrix is the line normal to the XAxis of the ellipse in the local plane (Z = 0) at a distance d = MajorRadius / e from the center of the ellipse, where e is the eccentricity of the ellipse. This line is parallel to the "YAxis". The intersection point between directrix1 and the "XAxis" is the "Location" point of the directrix1. This point is on the positive side of the "XAxis". Raised if Eccentricity = 0.0. (The ellipse degenerates into a circle)

gp_Ax1	Directrix2 () const
	This line is obtained by the symmetrical transformation of "Directrix1" with respect to the "YAxis" of the ellipse.

double	Eccentricity () const final
	Returns the eccentricity of the ellipse between 0.0 and 1.0 If f is the distance between the center of the ellipse and the Focus1 then the eccentricity e = f / MajorRadius. Returns 0 if MajorRadius = 0.

double	Focal () const
	Computes the focal distance. It is the distance between the the two focus of the ellipse.

gp_Pnt	Focus1 () const
	Returns the first focus of the ellipse. This focus is on the positive side of the "XAxis" of the ellipse.

gp_Pnt	Focus2 () const
	Returns the second focus of the ellipse. This focus is on the negative side of the "XAxis" of the ellipse.

double	MajorRadius () const
	Returns the major radius of this ellipse.

double	MinorRadius () const
	Returns the minor radius of this ellipse.

double	Parameter () const
	Returns p = (1 - e * e) * MajorRadius where e is the eccentricity of the ellipse. Returns 0 if MajorRadius = 0.

double	FirstParameter () const final
	Returns the value of the first parameter of this ellipse. This is respectively:

double	LastParameter () const final
	Returns the value of the last parameter of this ellipse. This is respectively:

bool	IsClosed () const final
	return True.

bool	IsPeriodic () const final
	return True.

gp_Pnt	EvalD0 (const double U) const final
	Returns the point of parameter U. P = C + MajorRadius * Cos (U) * XDir + MinorRadius * Sin (U) * YDir where C is the center of the ellipse , XDir the direction of the "XAxis" and "YDir" the "YAxis" of the ellipse.

Geom_Curve::ResD1	EvalD1 (const double U) const final
	Returns the point of parameter U and the first derivative.

Geom_Curve::ResD2	EvalD2 (const double U) const final
	Returns the point of parameter U and the first and second derivatives.

Geom_Curve::ResD3	EvalD3 (const double U) const final
	Returns the point of parameter U, the first, second and third derivatives.

gp_Vec	EvalDN (const double U, const int N) const final
	For the point of parameter U of this ellipse, computes the vector corresponding to the Nth derivative. Exceptions Standard_RangeError if N is less than 1.

void	Transform (const gp_Trsf &T) final
	Applies the transformation T to this ellipse.

occ::handle< Geom_Geometry >	Copy () const final
	Creates a new object which is a copy of this ellipse.

void	DumpJson (Standard_OStream &theOStream, int theDepth=-1) const final
	Dumps the content of me into the stream.

Public Member Functions inherited from Geom_Conic
void	SetAxis (const gp_Ax1 &theA1)
	Changes the orientation of the conic's plane. The normal axis to the plane is A1. The XAxis and the YAxis are recomputed.

void	SetLocation (const gp_Pnt &theP)
	changes the location point of the conic.

void	SetPosition (const gp_Ax2 &theA2)
	changes the local coordinate system of the conic.

const gp_Ax1 &	Axis () const
	Returns the "main Axis" of this conic. This axis is normal to the plane of the conic.

const gp_Pnt &	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 Apex of the parabola.

const gp_Ax2 &	Position () const
	Returns the local coordinates system of the conic. The main direction of the Axis2Placement is normal to the plane of the conic. The X direction of the Axis2placement is in the plane of the conic and corresponds to the origin for the conic's parametric value u.

gp_Ax1	XAxis () const
	Returns the XAxis of the conic. This axis defines the origin of parametrization of the conic. This axis is perpendicular to the Axis of the conic. This axis and the Yaxis define the plane of the conic.

gp_Ax1	YAxis () const
	Returns the YAxis of the conic. The YAxis is perpendicular to the Xaxis. This axis and the Xaxis define the plane 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
	The continuity of the conic is Cn.

bool	IsCN (const int N) const override
	Returns True. Raised if N < 0.

Public Member Functions inherited from Geom_Curve
virtual double	TransformedParameter (const double U, const gp_Trsf &T) const
	Returns the parameter on the transformed curve for the transform of the point of parameter U on <me>.

virtual double	ParametricTransformation (const gp_Trsf &T) const
	Returns a coefficient to compute the parameter on the transformed curve for the transform of the point on <me>.

occ::handle< Geom_Curve >	Reversed () const
	Returns a copy of <me> reversed.

virtual double	Period () const
	Returns the period of this curve. Exceptions Standard_NoSuchObject if this curve is not periodic.

void	D0 (const double U, gp_Pnt &P) const
	Returns in P the point of parameter U.

void	D1 (const double U, gp_Pnt &P, gp_Vec &V1) const
	Returns the point P of parameter U and the first derivative V1.

void	D2 (const double U, gp_Pnt &P, gp_Vec &V1, gp_Vec &V2) const
	Returns the point P of parameter U, the first and second derivatives V1 and V2.

void	D3 (const double U, gp_Pnt &P, gp_Vec &V1, gp_Vec &V2, gp_Vec &V3) const
	Returns the point P of parameter U, the first, the second and the third derivative.

gp_Vec	DN (const double U, const int N) const
	The returned vector gives the value of the derivative for the order of derivation N.

gp_Pnt	Value (const double U) const
	Computes the point of parameter U on <me>.

Public Member Functions inherited from Geom_Geometry
void	Mirror (const gp_Pnt &P)
	Performs the symmetrical transformation of a Geometry with respect to the point P which is the center of the symmetry.

void	Mirror (const gp_Ax1 &A1)
	Performs the symmetrical transformation of a Geometry with respect to an axis placement which is the axis of the symmetry.

void	Mirror (const gp_Ax2 &A2)
	Performs the symmetrical transformation of a Geometry with respect to a plane. The axis placement A2 locates the plane of the symmetry : (Location, XDirection, YDirection).

void	Rotate (const gp_Ax1 &A1, const double Ang)
	Rotates a Geometry. A1 is the axis of the rotation. Ang is the angular value of the rotation in radians.

void	Scale (const gp_Pnt &P, const double S)
	Scales a Geometry. S is the scaling value.

void	Translate (const gp_Vec &V)
	Translates a Geometry. V is the vector of the translation.

void	Translate (const gp_Pnt &P1, const gp_Pnt &P2)
	Translates a Geometry from the point P1 to the point P2.

occ::handle< Geom_Geometry >	Mirrored (const gp_Pnt &P) const

occ::handle< Geom_Geometry >	Mirrored (const gp_Ax1 &A1) const

occ::handle< Geom_Geometry >	Mirrored (const gp_Ax2 &A2) const

occ::handle< Geom_Geometry >	Rotated (const gp_Ax1 &A1, const double Ang) const

occ::handle< Geom_Geometry >	Scaled (const gp_Pnt &P, const double S) const

occ::handle< Geom_Geometry >	Transformed (const gp_Trsf &T) const

occ::handle< Geom_Geometry >	Translated (const gp_Vec &V) const

occ::handle< Geom_Geometry >	Translated (const gp_Pnt &P1, const gp_Pnt &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
Public Types inherited from Standard_Transient
typedef void	base_type
	Returns a type descriptor about this object.

Static Public Member Functions inherited from Standard_Transient
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 Geom_Conic
gp_Ax2	pos

Detailed Description

Describes an ellipse in 3D space. An ellipse is defined by its major and minor radii and, as with any conic curve, is positioned in space with a right-handed coordinate system (gp_Ax2 object) where:

the origin is the center of the ellipse,
the "X Direction" defines the major axis, and
the "Y Direction" defines the minor axis. The origin, "X Direction" and "Y Direction" of this coordinate system define the plane of the ellipse. The coordinate system is the local coordinate system of the ellipse. The "main Direction" of this coordinate system is the vector normal to the plane of the ellipse. The axis, of which the origin and unit vector are respectively the origin and "main Direction" of the local coordinate system, is termed the "Axis" or "main Axis" of the ellipse. The "main Direction" of the local coordinate system gives an explicit orientation to the ellipse (definition of the trigonometric sense), determining the direction in which the parameter increases along the ellipse. The Geom_Ellipse ellipse is parameterized by an angle: P(U) = O + MajorRad*std::cos(U)*XDir + MinorRad*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,
MajorRad and MinorRad are the major and minor radii of the ellipse. The "X Axis" of the local coordinate system therefore defines the origin of the parameter of the ellipse. An ellipse is a closed and periodic curve. The period is 2.*Pi and the parameter range is [ 0, 2.*Pi [.

Constructor & Destructor Documentation

◆ Geom_Ellipse() [1/2]

Geom_Ellipse::Geom_Ellipse ( const gp_Elips & E )

Constructs an ellipse by conversion of the gp_Elips ellipse E.

◆ Geom_Ellipse() [2/2]

Geom_Ellipse::Geom_Ellipse	(	const gp_Ax2 &	A2,
		const double	MajorRadius,
		const double	MinorRadius )

Constructs an ellipse defined by its major and minor radii, MajorRadius and MinorRadius, where A2 locates the ellipse and defines its orientation in 3D space such that:

the center of the ellipse is the origin of A2,
the "X Direction" of A2 defines the major axis of the ellipse, i.e. the major radius MajorRadius is measured along this axis,
the "Y Direction" of A2 defines the minor axis of the ellipse, i.e. the minor radius MinorRadius is measured along this axis,
A2 is the local coordinate system of the ellipse. Exceptions Standard_ConstructionError if:
MajorRadius is less than MinorRadius, or
MinorRadius is less than 0. Warning The Geom package does not prevent the construction of an ellipse where MajorRadius and MinorRadius are equal.

Member Function Documentation

◆ Copy()

occ::handle< Geom_Geometry > Geom_Ellipse::Copy ( ) const

finalvirtual

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

Implements Geom_Geometry.

◆ Directrix1()

gp_Ax1 Geom_Ellipse::Directrix1 ( ) const

This directrix is the line normal to the XAxis of the ellipse in the local plane (Z = 0) at a distance d = MajorRadius / e from the center of the ellipse, where e is the eccentricity of the ellipse. This line is parallel to the "YAxis". The intersection point between directrix1 and the "XAxis" is the "Location" point of the directrix1. This point is on the positive side of the "XAxis". Raised if Eccentricity = 0.0. (The ellipse degenerates into a circle)

◆ Directrix2()

gp_Ax1 Geom_Ellipse::Directrix2 ( ) const

This line is obtained by the symmetrical transformation of "Directrix1" with respect to the "YAxis" of the ellipse.

Raised if Eccentricity = 0.0. (The ellipse degenerates into a circle).

◆ DumpJson()

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

finalvirtual

Dumps the content of me into the stream.

Reimplemented from Geom_Conic.

◆ Eccentricity()

double Geom_Ellipse::Eccentricity ( ) const

finalvirtual

Returns the eccentricity of the ellipse between 0.0 and 1.0 If f is the distance between the center of the ellipse and the Focus1 then the eccentricity e = f / MajorRadius. Returns 0 if MajorRadius = 0.

gp_Vec Geom_Ellipse::EvalDN	(	const double	U,
		const int	N ) const

finalvirtual

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

Implements Geom_Curve.

◆ FirstParameter()

double Geom_Ellipse::FirstParameter ( ) const

finalvirtual

Returns the value of the first parameter of this ellipse. This is respectively:

0.0, which gives the start point of this ellipse, or The start point and end point of an ellipse are coincident.

Implements Geom_Curve.

◆ Focal()

double Geom_Ellipse::Focal ( ) const

Computes the focal distance. It is the distance between the the two focus of the ellipse.

◆ Focus1()

gp_Pnt Geom_Ellipse::Focus1 ( ) const

Returns the first focus of the ellipse. This focus is on the positive side of the "XAxis" of the ellipse.

◆ Focus2()

gp_Pnt Geom_Ellipse::Focus2 ( ) const

Returns the second focus of the ellipse. This focus is on the negative side of the "XAxis" of the ellipse.

◆ IsClosed()

bool Geom_Ellipse::IsClosed ( ) const

finalvirtual

return True.

Implements Geom_Curve.

◆ IsPeriodic()

bool Geom_Ellipse::IsPeriodic ( ) const

finalvirtual

return True.

Implements Geom_Curve.

◆ LastParameter()

double Geom_Ellipse::LastParameter ( ) const

finalvirtual

Returns the value of the last parameter of this ellipse. This is respectively:

2.*Pi, which gives the end point of this ellipse. The start point and end point of an ellipse are coincident.

Implements Geom_Curve.

◆ MajorRadius()

double Geom_Ellipse::MajorRadius ( ) const

Returns the major radius of this ellipse.

◆ MinorRadius()

double Geom_Ellipse::MinorRadius ( ) const

Returns the minor radius of this ellipse.

◆ Parameter()

double Geom_Ellipse::Parameter ( ) const

Returns p = (1 - e * e) * MajorRadius where e is the eccentricity of the ellipse. Returns 0 if MajorRadius = 0.

◆ ReversedParameter()

double Geom_Ellipse::ReversedParameter ( const double U ) const

finalvirtual

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

Implements Geom_Conic.

◆ SetElips()

void Geom_Ellipse::SetElips ( const gp_Elips & E )

Converts the gp_Elips ellipse E into this ellipse.

◆ SetMajorRadius()

void Geom_Ellipse::SetMajorRadius ( const double MajorRadius )

Assigns a value to the major radius of this ellipse. ConstructionError raised if MajorRadius < MinorRadius.

◆ SetMinorRadius()

void Geom_Ellipse::SetMinorRadius ( const double MinorRadius )

Assigns a value to the minor radius of this ellipse. ConstructionError raised if MajorRadius < MinorRadius or if MinorRadius < 0.

◆ Transform()

void Geom_Ellipse::Transform ( const gp_Trsf & T )

finalvirtual

Applies the transformation T to this ellipse.

Implements Geom_Geometry.

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

Geom_Ellipse.hxx

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Geom_Ellipse() [1/2]

◆ Geom_Ellipse() [2/2]

Member Function Documentation

◆ Copy()

◆ Directrix1()

◆ Directrix2()

◆ DumpJson()

◆ Eccentricity()

◆ Elips()

◆ EvalD0()

◆ EvalD1()

◆ EvalD2()

◆ EvalD3()

◆ EvalDN()

◆ FirstParameter()

◆ Focal()

◆ Focus1()

◆ Focus2()

◆ IsClosed()

◆ IsPeriodic()

◆ LastParameter()

◆ MajorRadius()

◆ MinorRadius()

◆ Parameter()

◆ ReversedParameter()

◆ SetElips()

◆ SetMajorRadius()

◆ SetMinorRadius()

◆ Transform()