include/Geant4/G4ErrorPropagationNavigator.hh

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0025 //
0026 // G4ErrorPropagationNavigator
0027 //
0028 // Class Description:
0029 //
0030 // Class for performing double navigation in the detector geometry and
0031 // on the target surface for error propagation. It overloads ComputeStep()
0032 // and ComputeSafety() methods.
0033
0034 // Author: Pedro Arce (CIEMAT), September 2004
0035 // --------------------------------------------------------------------
0036 #ifndef G4ErrorPropagationNavigator_hh
0037 #define G4ErrorPropagationNavigator_hh 1
0038
0039 #include "G4Navigator.hh"
0040 #include "G4ThreeVector.hh"
0041
0042 /**
0043  * @brief G4ErrorPropagationNavigator is a class for performing double
0044  * navigation in the detector geometry and on the target surface for error
0045  * propagation. It overloads ComputeStep() and ComputeSafety() methods.
0046  */
0047
0048 class G4ErrorPropagationNavigator : public G4Navigator
0049 {
0050   public:
0051
0052     /**
0053      * Constructor and Destructor.
0054      */
0055     G4ErrorPropagationNavigator() = default;
0056     ~G4ErrorPropagationNavigator() override = default;
0057
0058     /**
0059      * Calls the navigation in the detector geometry and then checks
0060      * if the distance to surface is smaller than the proposed step.
0061      *  @param[in] pGlobalPoint The point in global coordinates system.
0062      *  @param[in] pDirection The normalised vector direction.
0063      *  @param[in] pCurrentProposedStepLength Current proposed step length.
0064      *  @param[in,out] newSafety New safety.
0065      *  @returns Length from current point to next boundary surface along
0066      *           @p pDirection.
0067      */
0068     G4double ComputeStep (const G4ThreeVector& pGlobalPoint,
0069                           const G4ThreeVector& pDirection,
0070                           const G4double pCurrentProposedStepLength,
0071                                 G4double &pNewSafety) override;
0072
0073     /**
0074      * Calls the navigation in the detector geometry and then checks
0075      * if the distance to surface is smaller than the proposed safety.
0076      *  @param[in] globalpoint The point in global coordinates system.
0077      *             The point must be within the current volume.
0078      *  @param[in] pProposedMaxLength The proposed maximum length is used
0079      *             to avoid volume safety calculations.
0080      *  @param[in] keepState Flag to instruct keeping the state (default true)
0081      *             to ensure minimum side effects from the call.
0082      *  @returns Length from current point to closest boundary surface.
0083      *           The value returned is usually an underestimate.
0084      */
0085     G4double ComputeSafety(const G4ThreeVector& globalpoint,
0086                            const G4double pProposedMaxLength = DBL_MAX,
0087                            const G4bool keepState = true) override;
0088
0089     /**
0090      * Returns Exit Surface Normal and validity too. Can only be called if
0091      * the Navigator's last Step has crossed a volume geometrical boundary.
0092      * Normal points out of the volume exited and/or into the volume entered.
0093      *  @param[in] point Point in global coordinates system to compare to.
0094      *  @param[in,out] valid Flag indicating if normal is valid.
0095      *  @returns A Exit Surface Normal vector and validity too.
0096      */
0097     G4ThreeVector GetGlobalExitNormal(const G4ThreeVector& point,
0098                                             G4bool* valid) override;
0099
0100     /**
0101      * Computes the isotropic safety for 'Target'.
0102      *  @param[in] pGlobalpoint Point in global coordinates system.
0103      *  @returns The isotropic safety value.
0104      */
0105     G4double TargetSafetyFromPoint( const G4ThreeVector& pGlobalpoint );
0106 };
0107
0108 #endif