class Geometry

(Return to index)

Abstract base class for accelerator geometry classes.

A Geometry can be considered a 3-dimensional space line parameterised by the distance along the line (arc length) s. All Geometries have an exit and entrance plane and an origin. At any position s, a Geometry can define a unique 3-d rectilinear coordinate frame whose origin is on the geometry at s, and whose local z-axis is tangential to the geometry at s. The orientation of the local x- and y-axes are arbitrarilly specified by the Geometry. A special frame, referred to as the Geometry Local Frame (or Local Frame when it is unambiguous) is specified at s = origin. The Local Frame is is used to define that frame about which translations and rotations can be applied to the Geometry. The entrance and exit planes are defined as those x-y planes (z=0, s=constant) in the frames defined at s=entrance and s=exit.

Type:	Abstract
Include file:	./BeamlineGeometry/Geometry.hh

Inheritance

Synopsis (including inherited members):

• Public members:
  • Geometry () ;
  • Geometry (const Geometry&) ;
  • virtual ~Geometry () ;
  • const Geometry& operator= (const Geometry&) ;
  • virtual double getArcLength ()const = 0 ;
  • virtual double getElementLength ()const = 0 ;
  • virtual void setElementLength (double) ;
  • virtual double getOrigin ()const ;
  • virtual double getEntrance ()const ;
  • virtual double getExit ()const ;
  • virtual Euclid3D getTransform (double,double)const = 0 ;
  • virtual Euclid3D getTransform (double)const ;
  • virtual Euclid3D getTotalTransform ()const ;
  • virtual Euclid3D getEntranceFrame ()const ;
  • virtual Euclid3D getExitFrame ()const ;
  • virtual Euclid3D getEntrancePatch ()const ;
  • virtual Euclid3D getExitPatch ()const ;

Documentation:

• Public members:

  virtual double getArcLength ()const = 0 ;

  Get arc length.
  Return the length of the geometry, measured along the design arc.

  virtual double getElementLength ()const = 0 ;

  Get geometry length.
  Return or the design length of the geometry. Depending on the element this may be the arc length or the straight length.

  virtual double getEntrance ()const ;

  Get entrance position.
  Return the arc length from the origin to the entrance of the geometry (non-positive).

  virtual Euclid3D getEntranceFrame ()const ;

  Get transform.
  Equivalent to getTransform(0.0, getEntrance()). Return the transform of the local coordinate system from the origin to the entrance of the element.

  virtual Euclid3D getEntrancePatch ()const ;

  Get patch.
  Returns the entrance patch (transformation) which is used to transform the global geometry to the local geometry for a misaligned element at its entrance. The default behaviour returns identity transformation. This function should be overidden by derived concrete classes which model complex geometries.

  virtual double getExit ()const ;

  Get exit position.
  Return the arc length from the origin to the exit of the geometry (non-negative).

  virtual Euclid3D getExitFrame ()const ;

  Get transform.
  Equivalent to getTransform(0.0, getExit()). Return the transform of the local coordinate system from the origin to the exit of the element.

  virtual Euclid3D getExitPatch ()const ;

  Get patch.
  Returns the entrance patch (transformation) which is used to transform the local geometry to the global geometry for a misaligned element at its exit. The default behaviour returns identity transformation. This function should be overidden by derived concrete classes which model complex geometries.

  virtual double getOrigin ()const ;

  Get origin position.
  Return the arc length from the entrance to the origin of the geometry (non-negative).

  virtual Euclid3D getTotalTransform ()const ;

  Get transform.
  Equivalent to getTransform(getEntrance(), getExit()). Return the transform of the local coordinate system from the entrance to the exit of the element.

  virtual Euclid3D getTransform (double,double)const = 0 ;

  Get transform.
  Return the transform of the local coordinate system from the position fromS to the position toS.

  virtual Euclid3D getTransform (double)const ;

  Get transform.
  Equivalent to getTransform(0.0, s). Return the transform of the local coordinate system from the origin and s.

  virtual void setElementLength (double) ;

  Set geometry length.
  Assign the design length of the geometry. Depending on the element this may be the arc length or the straight length.