Open CASCADE Technology 6.6.0
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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.
#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 | |
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: | |
void | SetLocation (const gp_Pnt2d &P) |
Modifies this conic, redefining its local coordinate system fully, by assigning A as this coordinate system. | |
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. | |
gp_Ax2d | YAxis () const |
Returns the "YAxis" of the conic. The "YAxis" is perpendicular to the "Xaxis". | |
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 | |
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 () |
Reverses the direction of parameterization of <me>. The local coordinate system of the conic is modified. | |
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>. | |
GeomAbs_Shape | Continuity () const |
Returns GeomAbs_CN which is the global continuity of any conic. | |
Standard_Boolean | IsCN (const Standard_Integer N) const |
Returns True, the order of continuity of a conic is infinite. | |
Protected Attributes | |
gp_Ax22d | pos |
GeomAbs_Shape Geom2d_Conic::Continuity | ( | ) | const [virtual] |
Implements Geom2d_Curve.
virtual Standard_Real Geom2d_Conic::Eccentricity | ( | ) | const [pure virtual] |
Implemented in Geom2d_Circle, Geom2d_Ellipse, Geom2d_Hyperbola, and Geom2d_Parabola.
Standard_Boolean Geom2d_Conic::IsCN | ( | const Standard_Integer | N | ) | const [virtual] |
Implements Geom2d_Curve.
gp_Pnt2d Geom2d_Conic::Location | ( | ) | const |
const gp_Ax22d& Geom2d_Conic::Position | ( | ) | const |
void Geom2d_Conic::Reverse | ( | ) | [virtual] |
Implements Geom2d_Curve.
virtual Standard_Real Geom2d_Conic::ReversedParameter | ( | const Standard_Real | U | ) | const [pure virtual] |
Implements Geom2d_Curve.
Implemented in Geom2d_Circle, Geom2d_Ellipse, Geom2d_Hyperbola, and Geom2d_Parabola.
void Geom2d_Conic::SetAxis | ( | const gp_Ax22d & | A | ) |
void Geom2d_Conic::SetLocation | ( | const gp_Pnt2d & | P | ) |
void Geom2d_Conic::SetXAxis | ( | const gp_Ax2d & | A | ) |
void Geom2d_Conic::SetYAxis | ( | const gp_Ax2d & | A | ) |
gp_Ax2d Geom2d_Conic::XAxis | ( | ) | const |
-C++: return const&
gp_Ax2d Geom2d_Conic::YAxis | ( | ) | const |
gp_Ax22d Geom2d_Conic::pos [protected] |