1 | // |
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2 | // ******************************************************************** |
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3 | // * License and Disclaimer * |
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4 | // * * |
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5 | // * The Geant4 software is copyright of the Copyright Holders of * |
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6 | // * the Geant4 Collaboration. It is provided under the terms and * |
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7 | // * conditions of the Geant4 Software License, included in the file * |
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8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
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9 | // * include a list of copyright holders. * |
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10 | // * * |
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11 | // * Neither the authors of this software system, nor their employing * |
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12 | // * institutes,nor the agencies providing financial support for this * |
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13 | // * work make any representation or warranty, express or implied, * |
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14 | // * regarding this software system or assume any liability for its * |
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15 | // * use. Please see the license in the file LICENSE and URL above * |
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16 | // * for the full disclaimer and the limitation of liability. * |
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17 | // * * |
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18 | // * This code implementation is the result of the scientific and * |
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19 | // * technical work of the GEANT4 collaboration. * |
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20 | // * By using, copying, modifying or distributing the software (or * |
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21 | // * any work based on the software) you agree to acknowledge its * |
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22 | // * use in resulting scientific publications, and indicate your * |
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23 | // * acceptance of all terms of the Geant4 Software license. * |
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24 | // ******************************************************************** |
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25 | // |
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26 | // |
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27 | // $Id: G4Navigator.hh,v 1.29 2009/11/30 11:59:52 japost Exp $ |
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28 | // GEANT4 tag $Name: geant4-09-04-beta-01 $ |
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29 | // |
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30 | // |
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31 | // class G4Navigator |
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32 | // |
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33 | // Class description: |
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34 | // |
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35 | // A class for use by the tracking management, able to obtain/calculate |
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36 | // dynamic tracking time information such as the distance to the next volume, |
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37 | // or to find the physical volume containing a given point in the world |
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38 | // reference system. The navigator maintains a transformation history and |
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39 | // other information to optimise the tracking time performance. |
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40 | |
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41 | // History: |
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42 | // - Created. Paul Kent, Jul 95/96 |
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43 | // - Zero step protections J.A. / G.C., Nov 2004 |
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44 | // - Added check mode G. Cosmo, Mar 2004 |
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45 | // - Made Navigator Abstract G. Cosmo, Nov 2003 |
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46 | // ********************************************************************* |
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47 | |
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48 | #ifndef G4NAVIGATOR_HH |
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49 | #define G4NAVIGATOR_HH |
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50 | |
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51 | #include "geomdefs.hh" |
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52 | |
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53 | #include "G4ThreeVector.hh" |
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54 | #include "G4AffineTransform.hh" |
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55 | #include "G4RotationMatrix.hh" |
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56 | |
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57 | #include "G4LogicalVolume.hh" // Used in inline methods |
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58 | #include "G4GRSVolume.hh" // " " |
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59 | #include "G4GRSSolid.hh" // " " |
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60 | #include "G4TouchableHandle.hh" // " " |
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61 | #include "G4TouchableHistoryHandle.hh" |
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62 | |
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63 | #include "G4NavigationHistory.hh" |
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64 | #include "G4NormalNavigation.hh" |
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65 | #include "G4VoxelNavigation.hh" |
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66 | #include "G4ParameterisedNavigation.hh" |
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67 | #include "G4ReplicaNavigation.hh" |
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68 | #include "G4RegularNavigation.hh" |
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69 | |
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70 | #include <iostream> |
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71 | |
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72 | class G4VPhysicalVolume; |
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73 | |
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74 | class G4Navigator |
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75 | { |
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76 | public: // with description |
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77 | |
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78 | friend std::ostream& operator << (std::ostream &os, const G4Navigator &n); |
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79 | |
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80 | G4Navigator(); |
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81 | // Constructor - initialisers and setup. |
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82 | |
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83 | virtual ~G4Navigator(); |
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84 | // Destructor. No actions. |
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85 | |
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86 | virtual G4double ComputeStep(const G4ThreeVector &pGlobalPoint, |
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87 | const G4ThreeVector &pDirection, |
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88 | const G4double pCurrentProposedStepLength, |
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89 | G4double &pNewSafety); |
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90 | // Calculate the distance to the next boundary intersected |
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91 | // along the specified NORMALISED vector direction and |
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92 | // from the specified point in the global coordinate |
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93 | // system. LocateGlobalPointAndSetup or LocateGlobalPointWithinVolume |
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94 | // must have been called with the same global point prior to this call. |
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95 | // The isotropic distance to the nearest boundary is also |
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96 | // calculated (usually an underestimate). The current |
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97 | // proposed Step length is used to avoid intersection |
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98 | // calculations: if it can be determined that the nearest |
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99 | // boundary is >pCurrentProposedStepLength away, kInfinity |
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100 | // is returned together with the computed isotropic safety |
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101 | // distance. Geometry must be closed. |
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102 | |
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103 | G4double CheckNextStep(const G4ThreeVector &pGlobalPoint, |
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104 | const G4ThreeVector &pDirection, |
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105 | const G4double pCurrentProposedStepLength, |
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106 | G4double &pNewSafety); |
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107 | // Same as above, but do not disturb the state of the Navigator. |
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108 | |
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109 | virtual |
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110 | G4VPhysicalVolume* ResetHierarchyAndLocate(const G4ThreeVector &point, |
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111 | const G4ThreeVector &direction, |
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112 | const G4TouchableHistory &h); |
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113 | |
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114 | // Resets the geometrical hierarchy and search for the volumes deepest |
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115 | // in the hierarchy containing the point in the global coordinate space. |
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116 | // The direction is used to check if a volume is entered. |
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117 | // The search begin is the geometrical hierarchy at the location of the |
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118 | // last located point, or the endpoint of the previous Step if |
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119 | // SetGeometricallyLimitedStep() has been called immediately before. |
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120 | // |
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121 | // Important Note: In order to call this the geometry MUST be closed. |
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122 | |
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123 | virtual |
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124 | G4VPhysicalVolume* LocateGlobalPointAndSetup(const G4ThreeVector& point, |
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125 | const G4ThreeVector* direction=0, |
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126 | const G4bool pRelativeSearch=true, |
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127 | const G4bool ignoreDirection=true); |
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128 | // Search the geometrical hierarchy for the volumes deepest in the hierarchy |
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129 | // containing the point in the global coordinate space. Two main cases are: |
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130 | // i) If pRelativeSearch=false it makes use of no previous/state |
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131 | // information. Returns the physical volume containing the point, |
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132 | // with all previous mothers correctly set up. |
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133 | // ii) If pRelativeSearch is set to true, the search begin is the |
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134 | // geometrical hierarchy at the location of the last located point, |
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135 | // or the endpoint of the previous Step if SetGeometricallyLimitedStep() |
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136 | // has been called immediately before. |
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137 | // The direction is used (to check if a volume is entered) if either |
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138 | // - the argument ignoreDirection is false, or |
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139 | // - the Navigator has determined that it is on an edge shared by two or |
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140 | // more volumes. (This is state information.) |
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141 | // |
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142 | // Important Note: In order to call this the geometry MUST be closed. |
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143 | |
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144 | virtual |
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145 | void LocateGlobalPointWithinVolume(const G4ThreeVector& position); |
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146 | // Notify the Navigator that a track has moved to the new Global point |
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147 | // 'position', that is known to be within the current safety. |
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148 | // No check is performed to ensure that it is within the volume. |
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149 | // This method can be called instead of LocateGlobalPointAndSetup ONLY if |
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150 | // the caller is certain that the new global point (position) is inside the |
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151 | // same volume as the previous position. Usually this can be guaranteed |
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152 | // only if the point is within safety. |
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153 | |
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154 | inline void LocateGlobalPointAndUpdateTouchableHandle( |
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155 | const G4ThreeVector& position, |
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156 | const G4ThreeVector& direction, |
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157 | G4TouchableHandle& oldTouchableToUpdate, |
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158 | const G4bool RelativeSearch = true); |
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159 | // First, search the geometrical hierarchy like the above method |
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160 | // LocateGlobalPointAndSetup(). Then use the volume found and its |
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161 | // navigation history to update the touchable. |
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162 | |
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163 | inline void LocateGlobalPointAndUpdateTouchable( |
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164 | const G4ThreeVector& position, |
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165 | const G4ThreeVector& direction, |
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166 | G4VTouchable* touchableToUpdate, |
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167 | const G4bool RelativeSearch = true); |
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168 | // First, search the geometrical hierarchy like the above method |
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169 | // LocateGlobalPointAndSetup(). Then use the volume found and its |
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170 | // navigation history to update the touchable. |
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171 | |
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172 | inline void LocateGlobalPointAndUpdateTouchable( |
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173 | const G4ThreeVector& position, |
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174 | G4VTouchable* touchableToUpdate, |
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175 | const G4bool RelativeSearch = true); |
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176 | // Same as the method above but missing direction. |
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177 | |
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178 | inline void SetGeometricallyLimitedStep(); |
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179 | // Inform the navigator that the previous Step calculated |
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180 | // by the geometry was taken in its entirety. |
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181 | |
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182 | virtual G4double ComputeSafety(const G4ThreeVector &globalpoint, |
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183 | const G4double pProposedMaxLength = DBL_MAX, |
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184 | const G4bool keepState = false); |
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185 | // Calculate the isotropic distance to the nearest boundary from the |
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186 | // specified point in the global coordinate system. |
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187 | // The globalpoint utilised must be within the current volume. |
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188 | // The value returned is usually an underestimate. |
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189 | // The proposed maximum length is used to avoid volume safety |
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190 | // calculations. The geometry must be closed. |
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191 | |
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192 | inline G4VPhysicalVolume* GetWorldVolume() const; |
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193 | // Return the current world (`topmost') volume. |
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194 | |
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195 | inline void SetWorldVolume(G4VPhysicalVolume* pWorld); |
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196 | // Set the world (`topmost') volume. This must be positioned at |
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197 | // origin (0,0,0) and unrotated. |
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198 | |
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199 | inline G4GRSVolume* CreateGRSVolume() const; |
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200 | inline G4GRSSolid* CreateGRSSolid() const; |
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201 | inline G4TouchableHistory* CreateTouchableHistory() const; |
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202 | // `Touchable' creation methods: caller has deletion responsibility. |
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203 | |
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204 | virtual G4TouchableHistoryHandle CreateTouchableHistoryHandle() const; |
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205 | // Returns a reference counted handle to a touchable history. |
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206 | |
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207 | virtual G4ThreeVector GetLocalExitNormal(G4bool* valid); |
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208 | // Returns Exit Surface Normal and validity too. |
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209 | // It can only be called if the Navigator's last Step has crossed a |
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210 | // volume geometrical boundary. |
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211 | // It returns the Normal to the surface pointing out of the volume that |
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212 | // was left behind and/or into the volume that was entered. |
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213 | // (The normal is in the coordinate system of the final volume.) |
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214 | // This function takes full care about how to calculate this normal, |
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215 | // but if the surfaces are not convex it will return valid=false. |
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216 | |
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217 | inline G4int GetVerboseLevel() const; |
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218 | inline void SetVerboseLevel(G4int level); |
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219 | // Get/Set Verbose(ness) level. |
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220 | // [if level>0 && G4VERBOSE, printout can occur] |
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221 | |
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222 | inline G4bool IsActive() const; |
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223 | // Verify if the navigator is active. |
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224 | inline void Activate(G4bool flag); |
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225 | // Activate/inactivate the navigator. |
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226 | |
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227 | inline G4bool EnteredDaughterVolume() const; |
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228 | // The purpose of this function is to inform the caller if the track is |
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229 | // entering a daughter volume while exiting from the current volume. |
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230 | // This method returns |
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231 | // - True only in case 1) above, that is when the Step has caused |
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232 | // the track to arrive at a boundary of a daughter. |
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233 | // - False in cases 2), 3) and 4), i.e. in all other cases. |
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234 | // This function is not guaranteed to work if SetGeometricallyLimitedStep() |
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235 | // was not called when it should have been called. |
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236 | inline G4bool ExitedMotherVolume() const; |
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237 | // Verify if the step has exited the mother volume. |
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238 | |
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239 | inline void CheckMode(G4bool mode); |
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240 | // Run navigation in "check-mode", therefore using additional |
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241 | // verifications and more strict correctness conditions. |
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242 | // Is effective only with G4VERBOSE set. |
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243 | inline G4bool IsCheckModeActive() { return fCheck; } |
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244 | |
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245 | void PrintState() const; |
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246 | // Print the internal state of the Navigator (for debugging). |
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247 | // The level of detail is according to the verbosity. |
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248 | |
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249 | inline const G4AffineTransform& GetGlobalToLocalTransform() const; |
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250 | inline const G4AffineTransform GetLocalToGlobalTransform() const; |
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251 | // Obtain the transformations Global/Local (and inverse). |
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252 | // Clients of these methods must copy the data if they need to keep it. |
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253 | |
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254 | inline void ResetStackAndState(); |
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255 | // Reset stack and minimum or navigator state machine necessary for reset |
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256 | // as needed by LocalGlobalPointAndSetup. |
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257 | // [Does not perform clears, resizes, or reset fLastLocatedPointLocal] |
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258 | |
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259 | inline G4int SeverityOfZeroStepping( G4int* noZeroSteps ) const; |
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260 | // Report on severity of error and number of zero steps, |
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261 | // in case Navigator is stuck and is returning zero steps. |
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262 | // Values: 1 (small problem), 5 (correcting), |
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263 | // 9 (ready to abandon), 10 (abandoned) |
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264 | |
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265 | // inline |
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266 | void SetSavedState(); |
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267 | // ( fValidExitNormal, fExitNormal, fExiting, fEntering, |
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268 | // fBlockedPhysicalVolume, fBlockedReplicaNo, fLastStepWasZero); |
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269 | // inline |
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270 | void RestoreSavedState(); |
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271 | // Copy aspects of the state, to enable a non-state changing |
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272 | // call to ComputeStep |
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273 | |
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274 | public: // with description |
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275 | |
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276 | inline G4ThreeVector GetCurrentLocalCoordinate() const; |
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277 | // Return the local coordinate of the point in the reference system |
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278 | // of its containing volume that was found by LocalGlobalPointAndSetup. |
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279 | // The local coordinate of the last located track. |
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280 | |
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281 | inline G4ThreeVector NetTranslation() const; |
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282 | inline G4RotationMatrix NetRotation() const; |
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283 | // Compute+return the local->global translation/rotation of current volume. |
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284 | |
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285 | protected: // with description |
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286 | inline G4ThreeVector ComputeLocalPoint(const G4ThreeVector& rGlobPoint) const; |
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287 | // Return position vector in local coordinate system, given a position |
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288 | // vector in world coordinate system. |
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289 | |
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290 | inline G4ThreeVector ComputeLocalAxis(const G4ThreeVector& pVec) const; |
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291 | // Return the local direction of the specified vector in the reference |
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292 | // system of the volume that was found by LocalGlobalPointAndSetup. |
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293 | // The Local Coordinates of point in world coordinate system. |
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294 | |
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295 | virtual void ResetState(); |
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296 | // Utility method to reset the navigator state machine. |
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297 | |
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298 | inline EVolume VolumeType(const G4VPhysicalVolume *pVol) const; |
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299 | // Characterise `type' of volume - normal/replicated/parameterised. |
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300 | |
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301 | inline EVolume CharacteriseDaughters(const G4LogicalVolume *pLog) const; |
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302 | // Characterise daughter of logical volume. |
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303 | |
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304 | inline G4int GetDaughtersRegularStructureId(const G4LogicalVolume *pLog) const; |
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305 | // Get regular structure ID of first daughter |
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306 | |
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307 | virtual void SetupHierarchy(); |
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308 | // Renavigate & reset hierarchy described by current history |
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309 | // o Reset volumes |
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310 | // o Recompute transforms and/or solids of replicated/parameterised |
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311 | // volumes. |
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312 | |
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313 | protected: // without description |
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314 | |
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315 | G4double kCarTolerance; |
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316 | // Geometrical tolerance for surface thickness of shapes. |
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317 | |
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318 | // |
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319 | // BEGIN State information |
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320 | // |
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321 | |
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322 | G4NavigationHistory fHistory; |
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323 | // Transformation and history of the current path |
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324 | // through the geometrical hierarchy. |
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325 | |
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326 | G4bool fEnteredDaughter; |
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327 | // A memory of whether in this Step a daughter volume is entered |
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328 | // (set in Compute & Locate). |
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329 | // After Compute: it expects to enter a daughter |
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330 | // After Locate: it has entered a daughter |
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331 | |
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332 | G4bool fExitedMother; |
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333 | // A similar memory whether the Step exited current "mother" volume |
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334 | // completely, not entering daughter. |
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335 | |
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336 | G4bool fWasLimitedByGeometry; |
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337 | // Set true if last Step was limited by geometry. |
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338 | |
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339 | G4ThreeVector fStepEndPoint; |
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340 | // Endpoint of last ComputeStep |
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341 | // - can be used for optimisation (eg when computing safety) |
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342 | |
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343 | G4int fVerbose; |
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344 | // Verbose(ness) level [if > 0, printout can occur]. |
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345 | |
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346 | private: |
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347 | |
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348 | G4bool fActive; |
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349 | // States if the navigator is activated or not. |
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350 | |
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351 | G4bool fEntering,fExiting; |
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352 | // Entering/Exiting volumes blocking/setup |
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353 | // o If exiting |
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354 | // volume ptr & replica number (set & used by Locate..()) |
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355 | // used for blocking on redescent of geometry |
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356 | // o If entering |
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357 | // volume ptr & replica number (set by ComputeStep(),used by |
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358 | // Locate..()) of volume for `automatic' entry |
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359 | |
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360 | G4VPhysicalVolume *fBlockedPhysicalVolume; |
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361 | G4int fBlockedReplicaNo; |
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362 | |
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363 | // G4VPhysicalVolume *fCandidatePhysicalVolume; // Unused |
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364 | // G4int fCandidateReplicaNo; |
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365 | |
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366 | G4ThreeVector fLastLocatedPointLocal; |
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367 | // Position of the last located point relative to its containing volume. |
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368 | G4bool fLocatedOutsideWorld; |
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369 | // Whether the last call to Locate methods left the world |
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370 | // G4PhysicalVolume* fLastVolumeLocated; |
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371 | |
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372 | G4bool fValidExitNormal; // Set true if have leaving volume normal |
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373 | G4ThreeVector fExitNormal; // Leaving volume normal, in the |
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374 | // volume containing the exited |
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375 | // volume's coordinate system |
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376 | G4ThreeVector fGrandMotherExitNormal; // Leaving volume normal, in its |
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377 | // own coordinate system |
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378 | |
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379 | // Count zero steps - as one or two can occur due to changing momentum at |
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380 | // a boundary or at an edge common between volumes |
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381 | // - several are likely a problem in the geometry |
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382 | // description or in the navigation |
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383 | // |
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384 | G4bool fLastStepWasZero; |
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385 | // Whether the last ComputeStep moved Zero. Used to check for edges. |
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386 | |
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387 | G4bool fLocatedOnEdge; |
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388 | // Whether the Navigator has detected an edge |
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389 | G4int fNumberZeroSteps; |
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390 | // Number of preceding moves that were Zero. Reset to 0 after finite step |
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391 | G4int fActionThreshold_NoZeroSteps; |
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392 | // After this many failed/zero steps, act (push etc) |
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393 | G4int fAbandonThreshold_NoZeroSteps; |
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394 | // After this many failed/zero steps, abandon track |
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395 | |
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396 | G4ThreeVector fPreviousSftOrigin; |
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397 | G4double fPreviousSafety; |
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398 | // Memory of last safety origin & value. Used in ComputeStep to ensure |
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399 | // that origin of current Step is in the same volume as the point of the |
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400 | // last relocation |
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401 | |
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402 | // |
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403 | // END State information |
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404 | // |
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405 | |
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406 | // Save key state information (NOT the navigation history stack) |
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407 | // |
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408 | struct G4SaveNavigatorState |
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409 | { |
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410 | G4ThreeVector sExitNormal; |
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411 | G4bool sValidExitNormal; |
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412 | G4bool sEntering, sExiting; |
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413 | G4VPhysicalVolume* spBlockedPhysicalVolume; |
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414 | G4int sBlockedReplicaNo; |
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415 | G4int sLastStepWasZero; |
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416 | |
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417 | // Potentially relevant |
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418 | // |
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419 | G4bool sLocatedOutsideWorld; |
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420 | G4ThreeVector sLastLocatedPointLocal; |
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421 | G4bool sEnteredDaughter, sExitedMother; |
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422 | G4ThreeVector sPreviousSftOrigin; |
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423 | G4double sPreviousSafety; |
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424 | } fSaveState; |
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425 | |
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426 | // Tracking Invariants |
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427 | // |
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428 | G4VPhysicalVolume *fTopPhysical; |
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429 | // A link to the topmost physical volume in the detector. |
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430 | // Must be positioned at the origin and unrotated. |
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431 | |
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432 | // Utility information |
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433 | // |
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434 | G4bool fCheck; |
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435 | // Check-mode flag [if true, more strict checks are performed]. |
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436 | G4bool fPushed; |
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437 | // Push flag [if true, means a stuck particle has been pushed]. |
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438 | |
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439 | // Helpers/Utility classes |
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440 | // |
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441 | G4NormalNavigation fnormalNav; |
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442 | G4VoxelNavigation fvoxelNav; |
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443 | G4ParameterisedNavigation fparamNav; |
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444 | G4ReplicaNavigation freplicaNav; |
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445 | G4RegularNavigation fregularNav; |
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446 | }; |
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447 | |
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448 | #include "G4Navigator.icc" |
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449 | |
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450 | #endif |
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451 | |
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452 | |
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453 | // NOTES: |
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454 | // |
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455 | // The following methods provide detailed information when a Step has |
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456 | // arrived at a geometrical boundary. They distinguish between the different |
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457 | // causes that can result in the track leaving its current volume. |
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458 | // |
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459 | // Four cases are possible: |
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460 | // |
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461 | // 1) The particle has reached a boundary of a daughter of the current volume: |
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462 | // (this could cause the relocation to enter the daughter itself |
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463 | // or a potential granddaughter or further descendant) |
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464 | // |
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465 | // 2) The particle has reached a boundary of the current |
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466 | // volume, exiting into a mother (regardless the level |
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467 | // at which it is located in the tree): |
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468 | // |
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469 | // 3) The particle has reached a boundary of the current |
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470 | // volume, exiting into a volume which is not in its |
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471 | // parental hierarchy: |
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472 | // |
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473 | // 4) The particle is not on a boundary between volumes: |
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474 | // the function returns an exception, and the caller is |
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475 | // reccomended to compare the G4touchables associated |
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476 | // to the preStepPoint and postStepPoint to handle this case. |
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477 | // |
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478 | // G4bool EnteredDaughterVolume() |
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479 | // G4bool IsExitNormalValid() |
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480 | // G4ThreeVector GetLocalExitNormal() |
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481 | // |
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482 | // The expected usefulness of these methods is to allow the caller to |
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483 | // determine how to compute the surface normal at the volume boundary. The two |
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484 | // possibilities are to obtain the normal from: |
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485 | // |
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486 | // i) the solid associated with the volume of the initial point of the Step. |
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487 | // This is valid for cases 2 and 3. |
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488 | // (Note that the initial point is generally the PreStepPoint of a Step). |
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489 | // or |
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490 | // |
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491 | // ii) the solid of the final point, ie of the volume after the relocation. |
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492 | // This is valid for case 1. |
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493 | // (Note that the final point is generally the PreStepPoint of a Step). |
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494 | // |
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495 | // This way the caller can always get a valid normal, pointing outside |
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496 | // the solid for which it is computed, that can be used at his own |
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497 | // discretion. |
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