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Public Member Functions
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*Cos(U)*XDir + R*Sin(U)*YDir
where:
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#include <Geom2d_Circle.hxx>

Inheritance diagram for Geom2d_Circle:
Inheritance graph
[legend]

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 Standard_Real Radius, const Standard_Boolean Sense=Standard_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 Standard_Real 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 Standard_Real R)
gp_Circ2d Circ2d () const
 Returns the non persistent circle from gp with the same
geometric properties as <me>.

Standard_Real Radius () const
 Returns the radius of this circle.

Standard_Real ReversedParameter (const Standard_Real U) const
 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.

Standard_Real Eccentricity () const
 Returns 0., which is the eccentricity of any circle.

Standard_Real FirstParameter () const
 Returns 0.0

Standard_Real LastParameter () const
 Returns 2*PI.

Standard_Boolean IsClosed () const
 returns True.

Standard_Boolean IsPeriodic () const
 returns True. The period of a circle is 2.*Pi.

void D0 (const Standard_Real U, gp_Pnt2d &P) const
 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.

void D1 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1) const
 Returns the point P of parameter U and the first derivative V1.

void D2 (const Standard_Real 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 Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2, gp_Vec2d &V3) const
 Returns the point P of parameter u, the first second and third
derivatives V1 V2 and V3.

gp_Vec2d DN (const Standard_Real U, const Standard_Integer N) const
 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)
 Applies the transformation T to this circle.

Handle_Geom2d_Geometry Copy () const
 Creates a new object which is a copy of this circle.


Detailed Description


Constructor & Destructor Documentation

  • 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

Handle_Geom2d_Geometry Geom2d_Circle::Copy ( ) const [virtual]

Implements Geom2d_Geometry.

void Geom2d_Circle::D0 ( const Standard_Real  U,
gp_Pnt2d P 
) const [virtual]

Implements Geom2d_Curve.

void Geom2d_Circle::D1 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1 
) const [virtual]

Implements Geom2d_Curve.

void Geom2d_Circle::D2 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1,
gp_Vec2d V2 
) const [virtual]

Implements Geom2d_Curve.

void Geom2d_Circle::D3 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1,
gp_Vec2d V2,
gp_Vec2d V3 
) const [virtual]

Implements Geom2d_Curve.

Implements Geom2d_Curve.

Implements Geom2d_Conic.

Implements Geom2d_Curve.

Implements Geom2d_Curve.

Implements Geom2d_Curve.

Implements Geom2d_Curve.

Implements Geom2d_Conic.

Implements Geom2d_Geometry.


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