Open CASCADE Technology
6.9.0

The abstract class Conic describes the common behavior of conic curves in 2D space and, in particular, their general characteristics. The Geom2d package provides four specific classes of conics: Geom2d_Circle, Geom2d_Ellipse, Geom2d_Hyperbola and Geom2d_Parabola. A conic is positioned in the plane with a coordinate system (gp_Ax22d object), where the origin is the center of the conic (or the apex in case of a parabola). This coordinate system is the local coordinate system of the conic. It gives the conic an explicit orientation, determining the direction in which the parameter increases along the conic. The "X Axis" of the local coordinate system also defines the origin of the parameter of the conic. More...
#include <Geom2d_Conic.hxx>
Public Member Functions  
void  SetAxis (const gp_Ax22d &A) 
Modifies this conic, redefining its local coordinate system partially, by assigning P as its origin. More...  
void  SetXAxis (const gp_Ax2d &A) 
void  SetYAxis (const gp_Ax2d &A) 
Assigns the origin and unit vector of axis A to the origin of the local coordinate system of this conic and either: More...  
void  SetLocation (const gp_Pnt2d &P) 
Modifies this conic, redefining its local coordinate system fully, by assigning A as this coordinate system. More...  
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&. More...  
gp_Ax2d  YAxis () const 
Returns the "YAxis" of the conic. The "YAxis" is perpendicular to the "Xaxis". More...  
virtual Standard_Real  Eccentricity () const =0 
returns the eccentricity value of the conic e. e = 0 for a circle 0 < e < 1 for an ellipse (e = 0 if MajorRadius = MinorRadius) e > 1 for a hyperbola e = 1 for a parabola More...  
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. More...  
const gp_Ax22d &  Position () const 
Returns the local coordinates system of the conic. More...  
void  Reverse () 
Reverses the direction of parameterization of <me>. The local coordinate system of the conic is modified. More...  
virtual Standard_Real  ReversedParameter (const Standard_Real U) const =0 
Returns the parameter on the reversed curve for the point of parameter U on <me>. More...  
GeomAbs_Shape  Continuity () const 
Returns GeomAbs_CN which is the global continuity of any conic. More...  
Standard_Boolean  IsCN (const Standard_Integer N) const 
Returns True, the order of continuity of a conic is infinite. More...  
Public Member Functions inherited from Geom2d_Curve  
virtual Standard_Real  TransformedParameter (const Standard_Real 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). More...  
virtual Standard_Real  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). More...  
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: More...  
virtual Standard_Real  FirstParameter () const =0 
Returns the value of the first parameter. Warnings : It can be RealFirst or RealLast from package Standard if the curve is infinite. More...  
virtual Standard_Real  LastParameter () const =0 
Value of the last parameter. Warnings : It can be RealFirst or RealLast from package Standard if the curve is infinite. More...  
virtual Standard_Boolean  IsClosed () const =0 
Returns true if the curve is closed. Examples : Some curves such as circle are always closed, others such as line are never closed (by definition). Some Curves such as OffsetCurve can be closed or not. These curves are considered as closed if the distance between the first point and the last point of the curve is lower or equal to the Resolution from package gp wich is a fixed criterion independant of the application. More...  
virtual Standard_Boolean  IsPeriodic () const =0 
Returns true if the parameter of the curve is periodic. It is possible only if the curve is closed and if the following relation is satisfied : for each parametric value U the distance between the point P(u) and the point P (u + T) is lower or equal to Resolution from package gp, T is the period and must be a constant. There are three possibilities : . the curve is never periodic by definition (SegmentLine) . the curve is always periodic by definition (Circle) . the curve can be defined as periodic (BSpline). In this case a function SetPeriodic allows you to give the shape of the curve. The general rule for this case is : if a curve can be periodic or not the default periodicity set is non periodic and you have to turn (explicitly) the curve into a periodic curve if you want the curve to be periodic. More...  
virtual Standard_Real  Period () const 
Returns thne period of this curve. raises if the curve is not periodic. More...  
virtual void  D0 (const Standard_Real U, gp_Pnt2d &P) const =0 
Returns in P the point of parameter U. If the curve is periodic then the returned point is P(U) with U = Ustart + (U  Uend) where Ustart and Uend are the parametric bounds of the curve. More...  
virtual void  D1 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1) const =0 
Returns the point P of parameter U and the first derivative V1. Raised if the continuity of the curve is not C1. More...  
virtual void  D2 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2) const =0 
Returns the point P of parameter U, the first and second derivatives V1 and V2. Raised if the continuity of the curve is not C2. More...  
virtual void  D3 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2, gp_Vec2d &V3) const =0 
Returns the point P of parameter U, the first, the second and the third derivative. Raised if the continuity of the curve is not C3. More...  
virtual gp_Vec2d  DN (const Standard_Real U, const Standard_Integer N) const =0 
For the point of parameter U of this curve, computes the vector corresponding to the Nth derivative. Exceptions StdFail_UndefinedDerivative if: More...  
gp_Pnt2d  Value (const Standard_Real U) const 
Computes the point of parameter U on <me>. If the curve is periodic then the returned point is P(U) with U = Ustart + (U  Uend) where Ustart and Uend are the parametric bounds of the curve. More...  
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. More...  
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. More...  
void  Rotate (const gp_Pnt2d &P, const Standard_Real Ang) 
Rotates a Geometry. P is the center of the rotation. Ang is the angular value of the rotation in radians. More...  
void  Scale (const gp_Pnt2d &P, const Standard_Real S) 
Scales a Geometry. S is the scaling value. More...  
void  Translate (const gp_Vec2d &V) 
Translates a Geometry. V is the vector of the tanslation. More...  
void  Translate (const gp_Pnt2d &P1, const gp_Pnt2d &P2) 
Translates a Geometry from the point P1 to the point P2. More...  
virtual void  Transform (const gp_Trsf2d &T)=0 
Transformation of a geometric object. This tansformation can be a translation, a rotation, a symmetry, a scaling or a complex transformation obtained by combination of the previous elementaries transformations. (see class Transformation of the package Geom2d). The following transformations have the same properties as the previous ones but they don't modified the object itself. A copy of the object is returned. More...  
Handle< Geom2d_Geometry >  Mirrored (const gp_Pnt2d &P) const 
Handle< Geom2d_Geometry >  Mirrored (const gp_Ax2d &A) const 
Handle< Geom2d_Geometry >  Rotated (const gp_Pnt2d &P, const Standard_Real Ang) const 
Handle< Geom2d_Geometry >  Scaled (const gp_Pnt2d &P, const Standard_Real S) const 
Handle< Geom2d_Geometry >  Transformed (const gp_Trsf2d &T) const 
Handle< Geom2d_Geometry >  Translated (const gp_Vec2d &V) const 
Handle< Geom2d_Geometry >  Translated (const gp_Pnt2d &P1, const gp_Pnt2d &P2) const 
virtual Handle< Geom2d_Geometry >  Copy () const =0 
Public Member Functions inherited from MMgt_TShared  
virtual void  Delete () const 
Memory deallocator for transient classes. More...  
Public Member Functions inherited from Standard_Transient  
Standard_Transient ()  
Empty constructor. More...  
Standard_Transient (const Standard_Transient &)  
Copy constructor – does nothing. More...  
Standard_Transient &  operator= (const Standard_Transient &) 
Assignment operator, needed to avoid copying reference counter. More...  
virtual  ~Standard_Transient () 
Destructor must be virtual. More...  
virtual const Handle_Standard_Type &  DynamicType () const 
Returns a type information object about this object. More...  
Standard_Boolean  IsInstance (const Handle_Standard_Type &theType) const 
Returns a true value if this is an instance of Type. More...  
Standard_Boolean  IsInstance (const Standard_CString theTypeName) const 
Returns a true value if this is an instance of TypeName. More...  
Standard_Boolean  IsKind (const 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. More...  
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. More...  
virtual Handle_Standard_Transient  This () const 
Returns a Handle which references this object. Must never be called to objects created in stack. More...  
Standard_Integer  GetRefCount () const 
Get the reference counter of this object. More...  
Protected Attributes  
gp_Ax22d  pos 
The abstract class Conic describes the common behavior of conic curves in 2D space and, in particular, their general characteristics. The Geom2d package provides four specific classes of conics: Geom2d_Circle, Geom2d_Ellipse, Geom2d_Hyperbola and Geom2d_Parabola. A conic is positioned in the plane with a coordinate system (gp_Ax22d object), where the origin is the center of the conic (or the apex in case of a parabola). This coordinate system is the local coordinate system of the conic. It gives the conic an explicit orientation, determining the direction in which the parameter increases along the conic. The "X Axis" of the local coordinate system also defines the origin of the parameter of the conic.

virtual 
Returns GeomAbs_CN which is the global continuity of any conic.
Implements Geom2d_Curve.

pure virtual 
returns the eccentricity value of the conic e. e = 0 for a circle 0 < e < 1 for an ellipse (e = 0 if MajorRadius = MinorRadius) e > 1 for a hyperbola e = 1 for a parabola
Implemented in Geom2d_Hyperbola, Geom2d_Ellipse, Geom2d_Parabola, and Geom2d_Circle.

virtual 
Returns True, the order of continuity of a conic is infinite.
Implements Geom2d_Curve.
gp_Pnt2d Geom2d_Conic::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& Geom2d_Conic::Position  (  )  const 
Returns the local coordinates system of the conic.

virtual 
Reverses the direction of parameterization of <me>. The local coordinate system of the conic is modified.
Implements Geom2d_Curve.

pure virtual 
Returns the parameter on the reversed curve for the point of parameter U on <me>.
Implements Geom2d_Curve.
Implemented in Geom2d_Ellipse, Geom2d_Hyperbola, Geom2d_Parabola, and Geom2d_Circle.
void Geom2d_Conic::SetAxis  (  const gp_Ax22d &  A  ) 
Modifies this conic, redefining its local coordinate system partially, by assigning P as its origin.
void Geom2d_Conic::SetLocation  (  const gp_Pnt2d &  P  ) 
Modifies this conic, redefining its local coordinate system fully, by assigning A as this coordinate system.
void Geom2d_Conic::SetXAxis  (  const gp_Ax2d &  A  ) 
void Geom2d_Conic::SetYAxis  (  const gp_Ax2d &  A  ) 
Assigns the origin and unit vector of axis A to the origin of the local coordinate system of this conic and either:
gp_Ax2d Geom2d_Conic::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 Geom2d_Conic::YAxis  (  )  const 
Returns the "YAxis" of the conic. The "YAxis" is perpendicular to the "Xaxis".

protected 