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Public Types | Public Member Functions

HelixPlaneCrossing Class Reference

#include <HelixPlaneCrossing.h>

Inheritance diagram for HelixPlaneCrossing:
HelixArbitraryPlaneCrossing HelixArbitraryPlaneCrossing2Order HelixBarrelPlaneCrossingByCircle HelixForwardPlaneCrossing

List of all members.

Public Types

typedef Basic3DVector< float > DirectionType
typedef Basic3DVector< float > PositionType
 the helix is passed to the constructor and does not appear in the interface

Public Member Functions

virtual DirectionType direction (double s) const =0
virtual std::pair< bool, double > pathLength (const Plane &)=0
virtual PositionType position (double s) const =0

Detailed Description

Abstract interface for the crossing of a helix with a plane.

Definition at line 12 of file HelixPlaneCrossing.h.


Member Typedef Documentation

Definition at line 22 of file HelixPlaneCrossing.h.

the helix is passed to the constructor and does not appear in the interface

The types for position and direction are frame-neutral (not global, local, etc.) so this interface can be used in any frame. Of course, the helix and the plane must be defined in the same frame, which is also the frame of the result.

Definition at line 21 of file HelixPlaneCrossing.h.


Member Function Documentation

virtual DirectionType HelixPlaneCrossing::direction ( double  s) const [pure virtual]

Returns the direction along the helix that corresponds to path length "s" from the starting point. As for position, the direction of the crossing with a plane (if it exists!) is given by direction( pathLength( plane)).

Implemented in HelixArbitraryPlaneCrossing, HelixArbitraryPlaneCrossing2Order, HelixBarrelPlaneCrossingByCircle, and HelixForwardPlaneCrossing.

Referenced by AnalyticalPropagator::propagateWithHelixCrossing().

virtual std::pair<bool,double> HelixPlaneCrossing::pathLength ( const Plane ) [pure virtual]

Propagation status (true if valid) and (signed) path length along the helix from the starting point to the plane. The starting point is given in the constructor.

Implemented in HelixArbitraryPlaneCrossing, HelixArbitraryPlaneCrossing2Order, HelixBarrelPlaneCrossingByCircle, and HelixForwardPlaneCrossing.

Referenced by AnalyticalPropagator::propagateWithHelixCrossing().

virtual PositionType HelixPlaneCrossing::position ( double  s) const [pure virtual]

Returns the position along the helix that corresponds to path length "s" from the starting point. If s is obtained from the pathLength method the position is the destination point, i.e. the position of the crossing with a plane (if it exists!) is given by position( pathLength( plane)).

Implemented in HelixArbitraryPlaneCrossing, HelixArbitraryPlaneCrossing2Order, HelixBarrelPlaneCrossingByCircle, and HelixForwardPlaneCrossing.

Referenced by AnalyticalPropagator::propagateWithHelixCrossing().