[831] | 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: G4SphericalSurface.cc,v 1.10 2006/06/29 18:42:41 gunter Exp $ |
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[850] | 28 | // GEANT4 tag $Name: HEAD $ |
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[831] | 29 | // |
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| 30 | // ---------------------------------------------------------------------- |
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| 31 | // GEANT 4 class source file |
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| 32 | // |
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| 33 | // G4SphericalSurface.cc |
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| 34 | // |
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| 35 | // ---------------------------------------------------------------------- |
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| 36 | |
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| 37 | #include "G4SphericalSurface.hh" |
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| 38 | |
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| 39 | |
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| 40 | /* |
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| 41 | G4SphericalSurface::G4SphericalSurface() : G4Surface() |
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| 42 | { // default constructor |
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| 43 | // default x_axis is ( 1.0, 0.0, 0.0 ), z_axis is ( 0.0, 0.0, 1.0 ), |
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| 44 | // default radius is 1.0 |
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| 45 | // default phi_1 is 0, phi_2 is 2*PI |
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| 46 | // default theta_1 is 0, theta_2 is PI |
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| 47 | x_axis = G4Vector3D( 1.0, 0.0, 0.0 ); |
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| 48 | z_axis = G4Vector3D( 0.0, 0.0, 1.0 ); |
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| 49 | radius = 1.0; |
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| 50 | phi_1 = 0.0; |
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| 51 | phi_2 = 2*pi; |
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| 52 | theta_1 = 0.0; |
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| 53 | theta_2 = pi; |
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| 54 | // OuterBoundary = new G4BREPPolyline(); |
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| 55 | } |
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| 56 | */ |
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| 57 | |
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| 58 | |
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| 59 | G4SphericalSurface::G4SphericalSurface( const G4Vector3D&, |
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| 60 | const G4Vector3D& xhat, |
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| 61 | const G4Vector3D& zhat, |
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| 62 | G4double r, |
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| 63 | G4double ph1, G4double ph2, |
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| 64 | G4double th1, G4double th2) |
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| 65 | //: G4Surface( o ) |
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| 66 | { |
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| 67 | // Require both x_axis and z_axis to be unit vectors |
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| 68 | G4double xhatmag = xhat.mag(); |
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| 69 | if ( xhatmag != 0.0 ) |
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| 70 | x_axis = xhat * (1/ xhatmag); // this makes the x_axis a unit vector |
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| 71 | else |
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| 72 | { |
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| 73 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface--" |
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| 74 | <<"x_axis has zero length\n" |
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| 75 | << "\tDefault x_axis of (1, 0, 0) is used.\n"; |
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| 76 | |
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| 77 | x_axis = G4Vector3D( 1.0, 0.0, 0.0 ); |
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| 78 | } |
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| 79 | |
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| 80 | G4double zhatmag = zhat.mag(); |
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| 81 | |
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| 82 | if (zhatmag != 0.0) |
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| 83 | z_axis = zhat *(1/ zhatmag); // this makes the z_axis a unit vector |
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| 84 | else |
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| 85 | { |
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| 86 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface--" |
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| 87 | <<"z_axis has zero length\n" |
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| 88 | << "\tDefault z_axis of (0, 0, 1) is used. \n"; |
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| 89 | |
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| 90 | z_axis = G4Vector3D( 0.0, 0.0, 1.0 ); |
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| 91 | } |
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| 92 | |
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| 93 | // Require radius to be non-negative |
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| 94 | if ( r >= 0.0 ) |
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| 95 | radius = r; |
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| 96 | else |
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| 97 | { |
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| 98 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface" |
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| 99 | << "--radius cannot be less than zero.\n" |
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| 100 | << "\tDefault radius of 1.0 is used.\n"; |
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| 101 | |
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| 102 | radius = 1.0; |
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| 103 | } |
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| 104 | |
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| 105 | // Require phi_1 in the range: 0 <= phi_1 < 2*PI |
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| 106 | // and phi_2 in the range: phi_1 < phi_2 <= phi_1 + 2*PI |
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| 107 | if ( ( ph1 >= 0.0 ) && ( ph1 < 2*pi ) ) |
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| 108 | phi_1 = ph1; |
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| 109 | else |
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| 110 | { |
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| 111 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface" |
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| 112 | << "--lower azimuthal limit is out of range\n" |
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| 113 | << "\tDefault angle of 0 is used.\n"; |
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| 114 | |
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| 115 | phi_1 = 0.0; |
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| 116 | } |
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| 117 | |
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| 118 | if ( ( ph2 > phi_1 ) && ( ph2 <= ( phi_1 + twopi ) ) ) |
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| 119 | phi_2 = ph2; |
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| 120 | else |
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| 121 | { |
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| 122 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface" |
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| 123 | << "--upper azimuthal limit is out of range\n" |
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| 124 | << "\tDefault angle of 2*PI is used.\n"; |
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| 125 | |
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| 126 | phi_2 = twopi; |
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| 127 | } |
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| 128 | |
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| 129 | // Require theta_1 in the range: 0 <= theta_1 < PI |
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| 130 | // and theta-2 in the range: theta_1 < theta_2 <= theta_1 + PI |
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| 131 | if ( ( th1 >= 0.0 ) && ( th1 < pi ) ) |
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| 132 | theta_1 = th1; |
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| 133 | else |
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| 134 | { |
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| 135 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface" |
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| 136 | << "--lower polar limit is out of range\n" |
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| 137 | << "\tDefault angle of 0 is used.\n"; |
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| 138 | |
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| 139 | theta_1 = 0.0; |
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| 140 | } |
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| 141 | |
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| 142 | if ( ( th2 > theta_1 ) && ( th2 <= ( theta_1 + pi ) ) ) |
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| 143 | theta_2 =th2; |
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| 144 | else |
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| 145 | { |
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| 146 | G4cerr << "Error in G4SphericalSurface::G4SphericalSurface" |
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| 147 | << "--upper polar limit is out of range\n" |
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| 148 | << "\tDefault angle of PI is used.\n"; |
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| 149 | |
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| 150 | theta_2 = pi; |
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| 151 | } |
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| 152 | } |
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| 153 | |
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| 154 | |
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| 155 | G4SphericalSurface::~G4SphericalSurface() |
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| 156 | { |
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| 157 | } |
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| 158 | |
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| 159 | /* |
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| 160 | G4SphericalSurface::G4SphericalSurface( const G4SphericalSurface& s ) |
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| 161 | : G4Surface( s.origin ) |
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| 162 | { x_axis = s.x_axis; |
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| 163 | z_axis = s.z_axis; |
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| 164 | radius = s.radius; |
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| 165 | phi_1 = s.phi_1; |
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| 166 | phi_2 = s.phi_2; |
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| 167 | theta_1 = s.theta_1; |
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| 168 | theta_2 = s.theta_2; |
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| 169 | } |
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| 170 | */ |
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| 171 | |
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| 172 | const char* G4SphericalSurface::NameOf() const |
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| 173 | { |
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| 174 | return "G4SphericalSurface"; |
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| 175 | } |
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| 176 | |
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| 177 | void G4SphericalSurface::PrintOn( std::ostream& os ) const |
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| 178 | { |
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| 179 | // printing function using C++ std::ostream class |
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| 180 | os << "G4SphericalSurface surface with origin: " << origin << "\t" |
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| 181 | << "radius: " << radius << "\n" |
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| 182 | << "\t local x_axis: " << x_axis |
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| 183 | << "\t local z_axis: " << z_axis << "\n" |
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| 184 | << "\t lower azimuthal limit: " << phi_1 << " radians\n" |
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| 185 | << "\t upper azimuthal limit: " << phi_2 << " radians\n" |
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| 186 | << "\t lower polar limit : " << theta_1 << " radians\n" |
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| 187 | << "\t upper polar limit : " << theta_2 << " radians\n"; |
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| 188 | } |
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| 189 | |
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| 190 | |
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| 191 | G4double G4SphericalSurface::HowNear( const G4Vector3D& x ) const |
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| 192 | { |
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| 193 | // Distance from the point x to the G4SphericalSurface. |
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| 194 | // The distance will be positive if the point is Inside the |
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| 195 | // G4SphericalSurface, negative if the point is outside. |
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| 196 | G4Vector3D d = G4Vector3D( x - origin ); |
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| 197 | G4double rad = d.mag(); |
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| 198 | return (radius - rad); |
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| 199 | } |
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| 200 | |
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| 201 | |
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| 202 | /* |
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| 203 | G4double G4SphericalSurface::distanceAlongRay( G4int which_way, |
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| 204 | const G4Ray* ry, |
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| 205 | G4Vector3D& p ) const |
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| 206 | { // Distance along a Ray (straight line with G4Vector3D) to leave or enter |
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| 207 | // a G4SphericalSurface. The input variable which_way should be set to +1 to |
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| 208 | // indicate leaving a G4SphericalSurface, -1 to indicate entering the surface. |
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| 209 | // p is the point of intersection of the Ray with the G4SphericalSurface. |
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| 210 | // If the G4Vector3D of the Ray is opposite to that of the Normal to |
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| 211 | // the G4SphericalSurface at the intersection point, it will not leave the |
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| 212 | // G4SphericalSurface. |
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| 213 | // Similarly, if the G4Vector3D of the Ray is along that of the Normal |
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| 214 | // to the G4SphericalSurface at the intersection point, it will not enter the |
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| 215 | // G4SphericalSurface. |
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| 216 | // This method is called by all finite shapes sub-classed to G4SphericalSurface. |
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| 217 | // Use the virtual function table to check if the intersection point |
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| 218 | // is within the boundary of the finite shape. |
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| 219 | // A negative result means no intersection. |
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| 220 | // If no valid intersection point is found, set the distance |
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| 221 | // and intersection point to large numbers. |
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| 222 | G4double Dist = FLT_MAXX; |
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| 223 | G4Vector3D lv ( FLT_MAXX, FLT_MAXX, FLT_MAXX ); |
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| 224 | p = lv; |
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| 225 | // Origin and G4Vector3D unit vector of Ray. |
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| 226 | G4Vector3D x = ry->Position( 0.0 ); |
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| 227 | G4Vector3D dhat = ry->Direction( 0.0 ); |
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| 228 | G4int isoln = 0, maxsoln = 2; |
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| 229 | // array of solutions in distance along the Ray |
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| 230 | // G4double s[2] = { -1.0, -1.0 }; |
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| 231 | G4double s[2];s[0] = -1.0; s[1]= -1.0 ; |
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| 232 | // calculate the two solutions (quadratic equation) |
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| 233 | G4Vector3D d = x - GetOrigin(); |
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| 234 | G4double radius = GetRadius(); |
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| 235 | // quit with no intersection if the radius of the G4SphericalSurface is zero |
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| 236 | if ( radius <= 0.0 ) |
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| 237 | return Dist; |
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| 238 | G4double dsq = d * d; |
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| 239 | G4double rsq = radius * radius; |
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| 240 | G4double b = d * dhat; |
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| 241 | G4double c = dsq - rsq; |
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| 242 | G4double radical = b * b - c; |
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| 243 | // quit with no intersection if the radical is negative |
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| 244 | if ( radical < 0.0 ) |
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| 245 | return Dist; |
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| 246 | G4double root = std::sqrt( radical ); |
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| 247 | s[0] = -b + root; |
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| 248 | s[1] = -b - root; |
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| 249 | // order the possible solutions by increasing distance along the Ray |
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| 250 | // (G4Sorting routines are in support/G4Sort.h) |
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| 251 | G4Sort_double( s, isoln, maxsoln-1 ); |
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| 252 | // now loop over each positive solution, keeping the first one (smallest |
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| 253 | // distance along the Ray) which is within the boundary of the sub-shape |
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| 254 | // and which also has the correct G4Vector3D with respect to the Normal to |
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| 255 | // the G4SphericalSurface at the intersection point |
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| 256 | for ( isoln = 0; isoln < maxsoln; isoln++ ) { |
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| 257 | if ( s[isoln] >= 0.0 ) { |
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| 258 | if ( s[isoln] >= FLT_MAXX ) // quit if too large |
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| 259 | return Dist; |
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| 260 | Dist = s[isoln]; |
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| 261 | p = ry->Position( Dist ); |
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| 262 | if ( ( ( dhat * Normal( p ) * which_way ) >= 0.0 ) |
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| 263 | && ( WithinBoundary( p ) == 1 ) ) |
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| 264 | return Dist; |
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| 265 | } |
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| 266 | } |
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| 267 | // get here only if there was no solution within the boundary, Reset |
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| 268 | // distance and intersection point to large numbers |
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| 269 | p = lv; |
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| 270 | return FLT_MAXX; |
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| 271 | } |
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| 272 | */ |
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| 273 | |
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| 274 | |
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| 275 | void G4SphericalSurface::CalcBBox() |
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| 276 | { |
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| 277 | G4double x_min = origin.x() - radius; |
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| 278 | G4double y_min = origin.y() - radius; |
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| 279 | G4double z_min = origin.z() - radius; |
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| 280 | G4double x_max = origin.x() + radius; |
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| 281 | G4double y_max = origin.y() + radius; |
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| 282 | G4double z_max = origin.z() + radius; |
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| 283 | |
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| 284 | G4Point3D Min(x_min, y_min, z_min); |
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| 285 | G4Point3D Max(x_max, y_max, z_max); |
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| 286 | bbox = new G4BoundingBox3D( Min, Max); |
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| 287 | } |
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| 288 | |
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| 289 | |
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| 290 | G4int G4SphericalSurface::Intersect( const G4Ray& ry ) |
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| 291 | { |
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| 292 | // Distance along a Ray (straight line with G4Vector3D) to leave or enter |
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| 293 | // a G4SphericalSurface. The input variable which_way should be set to +1 |
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| 294 | // to indicate leaving a G4SphericalSurface, -1 to indicate entering a |
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| 295 | // G4SphericalSurface. |
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| 296 | // p is the point of intersection of the Ray with the G4SphericalSurface. |
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| 297 | // If the G4Vector3D of the Ray is opposite to that of the Normal to |
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| 298 | // the G4SphericalSurface at the intersection point, it will not leave the |
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| 299 | // G4SphericalSurface. |
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| 300 | // Similarly, if the G4Vector3D of the Ray is along that of the Normal |
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| 301 | // to the G4SphericalSurface at the intersection point, it will not enter |
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| 302 | // the G4SphericalSurface. |
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| 303 | // This method is called by all finite shapes sub-classed to |
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| 304 | // G4SphericalSurface. |
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| 305 | // Use the virtual function table to check if the intersection point |
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| 306 | // is within the boundary of the finite shape. |
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| 307 | // A negative result means no intersection. |
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| 308 | // If no valid intersection point is found, set the distance |
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| 309 | // and intersection point to large numbers. |
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| 310 | |
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| 311 | G4int which_way = (G4int)HowNear(ry.GetStart()); |
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| 312 | //Originally a parameter.Read explanation above. |
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| 313 | |
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| 314 | if(!which_way)which_way =-1; |
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| 315 | distance = FLT_MAXX; |
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| 316 | |
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| 317 | G4Vector3D lv ( FLT_MAXX, FLT_MAXX, FLT_MAXX ); |
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| 318 | |
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| 319 | // p = lv; |
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| 320 | closest_hit = lv; |
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| 321 | |
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| 322 | // Origin and G4Vector3D unit vector of Ray. |
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| 323 | // G4Vector3D x = ry->position( 0.0 ); |
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| 324 | G4Vector3D x= G4Vector3D( ry.GetStart() ); |
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| 325 | |
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| 326 | // G4Vector3D dhat = ry->direction( 0.0 ); |
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| 327 | G4Vector3D dhat = ry.GetDir(); |
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| 328 | G4int isoln = 0, maxsoln = 2; |
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| 329 | |
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| 330 | // array of solutions in distance along the Ray |
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| 331 | G4double s[2]; |
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| 332 | s[0] = -1.0 ; |
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| 333 | s[1] = -1.0 ; |
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| 334 | |
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| 335 | // calculate the two solutions (quadratic equation) |
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| 336 | G4Vector3D d = G4Vector3D( x - GetOrigin() ); |
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| 337 | G4double r = GetRadius(); |
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| 338 | |
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| 339 | // quit with no intersection if the radius of the G4SphericalSurface is zero |
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| 340 | if ( r <= 0.0 ) |
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| 341 | return 0; |
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| 342 | |
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| 343 | G4double dsq = d * d; |
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| 344 | G4double rsq = r * r; |
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| 345 | G4double b = d * dhat; |
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| 346 | G4double c = dsq - rsq; |
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| 347 | G4double radical = b * b - c; |
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| 348 | |
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| 349 | // quit with no intersection if the radical is negative |
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| 350 | if ( radical < 0.0 ) |
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| 351 | return 0; |
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| 352 | |
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| 353 | G4double root = std::sqrt( radical ); |
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| 354 | s[0] = -b + root; |
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| 355 | s[1] = -b - root; |
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| 356 | |
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| 357 | // order the possible solutions by increasing distance along the Ray |
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| 358 | // (G4Sorting routines are in support/G4Sort.h) |
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| 359 | // G4Sort_double( s, isoln, maxsoln-1 ); |
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| 360 | if(s[0] > s[1]) |
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| 361 | { |
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| 362 | G4double tmp =s[0]; |
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| 363 | s[0] = s[1]; |
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| 364 | s[1] = tmp; |
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| 365 | } |
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| 366 | |
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| 367 | // now loop over each positive solution, keeping the first one (smallest |
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| 368 | // distance along the Ray) which is within the boundary of the sub-shape |
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| 369 | // and which also has the correct G4Vector3D with respect to the Normal to |
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| 370 | // the G4SphericalSurface at the intersection point |
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| 371 | for ( isoln = 0; isoln < maxsoln; isoln++ ) |
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| 372 | { |
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| 373 | if ( s[isoln] >= kCarTolerance*0.5 ) |
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| 374 | { |
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| 375 | if ( s[isoln] >= FLT_MAXX ) // quit if too large |
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| 376 | return 0; |
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| 377 | |
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| 378 | distance = s[isoln]; |
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| 379 | closest_hit = ry.GetPoint( distance ); |
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| 380 | if ( ( ( dhat * Normal( closest_hit ) * which_way ) >= 0.0 ) && |
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| 381 | ( WithinBoundary( closest_hit ) == 1 ) ) |
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| 382 | { |
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| 383 | distance = distance*distance; |
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| 384 | return 1; |
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| 385 | } |
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| 386 | } |
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| 387 | } |
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| 388 | |
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| 389 | // get here only if there was no solution within the boundary, Reset |
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| 390 | // distance and intersection point to large numbers |
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| 391 | // p = lv; |
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| 392 | // return FLT_MAXX; |
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| 393 | distance = FLT_MAXX; |
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| 394 | closest_hit = lv; |
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| 395 | return 0; |
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| 396 | } |
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| 397 | |
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| 398 | |
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| 399 | /* |
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| 400 | G4double G4SphericalSurface::distanceAlongHelix( G4int which_way, |
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| 401 | const Helix* hx, |
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| 402 | G4Vector3D& p ) const |
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| 403 | { // Distance along a Helix to leave or enter a G4SphericalSurface. |
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| 404 | // The input variable which_way should be set to +1 to |
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| 405 | // indicate leaving a G4SphericalSurface, -1 to indicate entering a G4SphericalSurface. |
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| 406 | // p is the point of intersection of the Helix with the G4SphericalSurface. |
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| 407 | // If the G4Vector3D of the Helix is opposite to that of the Normal to |
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| 408 | // the G4SphericalSurface at the intersection point, it will not leave the |
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| 409 | // G4SphericalSurface. |
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| 410 | // Similarly, if the G4Vector3D of the Helix is along that of the Normal |
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| 411 | // to the G4SphericalSurface at the intersection point, it will not enter the |
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| 412 | // G4SphericalSurface. |
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| 413 | // This method is called by all finite shapes sub-classed to G4SphericalSurface. |
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| 414 | // Use the virtual function table to check if the intersection point |
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| 415 | // is within the boundary of the finite shape. |
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| 416 | // If no valid intersection point is found, set the distance |
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| 417 | // and intersection point to large numbers. |
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| 418 | // Possible negative distance solutions are discarded. |
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| 419 | G4double Dist = FLT_MAXX; |
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| 420 | G4Vector3D lv ( FLT_MAXX, FLT_MAXX, FLT_MAXX ); |
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| 421 | p = lv; |
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| 422 | G4int isoln = 0, maxsoln = 4; |
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| 423 | // Array of solutions in turning angle |
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| 424 | // G4double s[4] = { -1.0, -1.0, -1.0, -1.0 }; |
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| 425 | G4double s[4];s[0] = -1.0; s[1]= -1.0 ;s[2] = -1.0; s[3]= -1.0 ; |
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| 426 | |
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| 427 | // Helix parameters |
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| 428 | G4double rh = hx->GetRadius(); // radius of Helix |
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| 429 | G4Vector3D oh = hx->position( 0.0 ); // origin of Helix |
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| 430 | G4Vector3D dh = hx->direction( 0.0 ); // initial G4Vector3D of Helix |
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| 431 | G4Vector3D prp = hx->getPerp(); // perpendicular vector |
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| 432 | G4double prpmag = prp.mag(); |
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| 433 | G4double rhp = rh / prpmag; |
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| 434 | // G4SphericalSurface parameters |
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| 435 | G4double rs = GetRadius(); // radius of G4SphericalSurface |
---|
| 436 | if ( rs == 0.0 ) // quit if zero radius |
---|
| 437 | return Dist; |
---|
| 438 | G4Vector3D os = GetOrigin(); // origin of G4SphericalSurface |
---|
| 439 | // |
---|
| 440 | // Calculate quantities of use later on |
---|
| 441 | G4Vector3D alpha = rhp * prp; |
---|
| 442 | G4Vector3D beta = rhp * dh; |
---|
| 443 | G4Vector3D gamma = oh - os; |
---|
| 444 | // |
---|
| 445 | // Only consider approximate solutions to quadratic order in the turning |
---|
| 446 | // angle along the Helix |
---|
| 447 | G4double A = beta * beta + gamma * alpha; |
---|
| 448 | G4double B = 2.0 * gamma * beta; |
---|
| 449 | G4double C = gamma * gamma - rs * rs; |
---|
| 450 | // Case if quadratic term is zero |
---|
| 451 | if ( std::fabs( A ) < FLT_EPSILO ) { |
---|
| 452 | if ( B == 0.0 ) // no intersection, quit |
---|
| 453 | return Dist; |
---|
| 454 | else // B != 0 |
---|
| 455 | s[0] = -C / B; |
---|
| 456 | } |
---|
| 457 | // General quadratic solution, A != 0 |
---|
| 458 | else { |
---|
| 459 | G4double radical = B * B - 4.0 * A * C; |
---|
| 460 | if ( radical < 0.0 ) // no intersection, quit |
---|
| 461 | return Dist; |
---|
| 462 | G4double root = std::sqrt( radical ); |
---|
| 463 | s[0] = ( -B + root ) / ( 2.0 * A ); |
---|
| 464 | s[1] = ( -B - root ) / ( 2.0 * A ); |
---|
| 465 | if ( rh < 0.0 ) { |
---|
| 466 | s[0] = -s[0]; |
---|
| 467 | s[1] = -s[1]; |
---|
| 468 | } |
---|
| 469 | s[2] = s[0] + twopi; |
---|
| 470 | s[3] = s[1] + twopi; |
---|
| 471 | } |
---|
| 472 | // |
---|
| 473 | // Order the possible solutions by increasing turning angle |
---|
| 474 | // (G4Sorting routines are in support/G4Sort.h). |
---|
| 475 | G4Sort_double( s, isoln, maxsoln-1 ); |
---|
| 476 | // |
---|
| 477 | // Now loop over each positive solution, keeping the first one (smallest |
---|
| 478 | // distance along the Helix) which is within the boundary of the sub-shape. |
---|
| 479 | for ( isoln = 0; isoln < maxsoln; isoln++ ) { |
---|
| 480 | if ( s[isoln] >= 0.0 ) { |
---|
| 481 | // Calculate distance along Helix and position and G4Vector3D vectors. |
---|
| 482 | Dist = s[isoln] * std::fabs( rhp ); |
---|
| 483 | p = hx->position( Dist ); |
---|
| 484 | G4Vector3D d = hx->direction( Dist ); |
---|
| 485 | // Now do approximation to get remaining distance to correct this solution |
---|
| 486 | // iterate it until the accuracy is below the user-set surface precision. |
---|
| 487 | G4double delta = 0.; |
---|
| 488 | G4double delta0 = FLT_MAXX; |
---|
| 489 | G4int dummy = 1; |
---|
| 490 | G4int iter = 0; |
---|
| 491 | G4int in0 = Inside( hx->position ( 0.0 ) ); |
---|
| 492 | G4int in1 = Inside( p ); |
---|
| 493 | G4double sc = Scale(); |
---|
| 494 | while ( dummy ) { |
---|
| 495 | iter++; |
---|
| 496 | // Terminate loop after 50 iterations and Reset distance to large number, |
---|
| 497 | // indicating no intersection with G4SphericalSurface. |
---|
| 498 | // This generally occurs if the Helix curls too tightly to Intersect it. |
---|
| 499 | if ( iter > 50 ) { |
---|
| 500 | Dist = FLT_MAXX; |
---|
| 501 | p = lv; |
---|
| 502 | break; |
---|
| 503 | } |
---|
| 504 | // Find distance from the current point along the above-calculated |
---|
| 505 | // G4Vector3D using a Ray. |
---|
| 506 | // The G4Vector3D of the Ray and the Sign of the distance are determined |
---|
| 507 | // by whether the starting point of the Helix is Inside or outside of |
---|
| 508 | // the G4SphericalSurface. |
---|
| 509 | in1 = Inside( p ); |
---|
| 510 | if ( in1 ) { // current point Inside |
---|
| 511 | if ( in0 ) { // starting point Inside |
---|
| 512 | Ray* r = new Ray( p, d ); |
---|
| 513 | delta = |
---|
| 514 | distanceAlongRay( 1, r, p ); |
---|
| 515 | delete r; |
---|
| 516 | } |
---|
| 517 | else { // starting point outside |
---|
| 518 | Ray* r = new Ray( p, -d ); |
---|
| 519 | delta = |
---|
| 520 | -distanceAlongRay( 1, r, p ); |
---|
| 521 | delete r; |
---|
| 522 | } |
---|
| 523 | } |
---|
| 524 | else { // current point outside |
---|
| 525 | if ( in0 ) { // starting point Inside |
---|
| 526 | Ray* r = new Ray( p, -d ); |
---|
| 527 | delta = |
---|
| 528 | -distanceAlongRay( -1, r, p ); |
---|
| 529 | delete r; |
---|
| 530 | } |
---|
| 531 | else { // starting point outside |
---|
| 532 | Ray* r = new Ray( p, d ); |
---|
| 533 | delta = |
---|
| 534 | distanceAlongRay( -1, r, p ); |
---|
| 535 | delete r; |
---|
| 536 | } |
---|
| 537 | } |
---|
| 538 | // Test if distance is less than the surface precision, if so Terminate loop. |
---|
| 539 | if ( std::fabs( delta / sc ) <= SURFACE_PRECISION ) |
---|
| 540 | break; |
---|
| 541 | // Ff delta has not changed sufficiently from the previous iteration, |
---|
| 542 | // skip out of this loop. |
---|
| 543 | if ( std::fabs( ( delta - delta0 ) / sc ) <= |
---|
| 544 | SURFACE_PRECISION ) |
---|
| 545 | break; |
---|
| 546 | // If delta has increased in absolute value from the previous iteration |
---|
| 547 | // either the Helix doesn't Intersect the G4SphericalSurface or the approximate |
---|
| 548 | // solution is too far from the real solution. Try groping for a solution. |
---|
| 549 | // If not found, Reset distance to large number, indicating no intersection |
---|
| 550 | // with the G4SphericalSurface. |
---|
| 551 | if ( ( std::fabs( delta ) > std::fabs( delta0 ) ) ) { |
---|
| 552 | Dist = std::fabs( rhp ) * |
---|
| 553 | gropeAlongHelix( hx ); |
---|
| 554 | if ( Dist < 0.0 ) { |
---|
| 555 | Dist = FLT_MAXX; |
---|
| 556 | p = lv; |
---|
| 557 | } |
---|
| 558 | else |
---|
| 559 | p = hx->position( Dist ); |
---|
| 560 | break; |
---|
| 561 | } |
---|
| 562 | // Set old delta to new one. |
---|
| 563 | delta0 = delta; |
---|
| 564 | // Add distance to G4SphericalSurface to distance along Helix. |
---|
| 565 | Dist += delta; |
---|
| 566 | // Negative distance along Helix means Helix doesn't Intersect G4SphericalSurface. |
---|
| 567 | // Reset distance to large number, indicating no intersection with G4SphericalSurface. |
---|
| 568 | if ( Dist < 0.0 ) { |
---|
| 569 | Dist = FLT_MAXX; |
---|
| 570 | p = lv; |
---|
| 571 | break; |
---|
| 572 | } |
---|
| 573 | // Recalculate point along Helix and the G4Vector3D. |
---|
| 574 | p = hx->position( Dist ); |
---|
| 575 | d = hx->direction( Dist ); |
---|
| 576 | } // end of while loop |
---|
| 577 | // Now have best value of distance along Helix and position for this |
---|
| 578 | // solution, so test if it is within the boundary of the sub-shape |
---|
| 579 | // and require that it point in the correct G4Vector3D with respect to |
---|
| 580 | // the Normal to the G4SphericalSurface. |
---|
| 581 | if ( ( Dist < FLT_MAXX ) && |
---|
| 582 | ( ( hx->direction( Dist ) * Normal( p ) * |
---|
| 583 | which_way ) >= 0.0 ) && |
---|
| 584 | ( WithinBoundary( p ) == 1 ) ) |
---|
| 585 | return Dist; |
---|
| 586 | } // end of if s[isoln] >= 0.0 condition |
---|
| 587 | } // end of for loop over solutions |
---|
| 588 | // If one gets here, there is no solution, so set distance along Helix |
---|
| 589 | // and position to large numbers. |
---|
| 590 | Dist = FLT_MAXX; |
---|
| 591 | p = lv; |
---|
| 592 | return Dist; |
---|
| 593 | } |
---|
| 594 | */ |
---|
| 595 | |
---|
| 596 | |
---|
| 597 | /* |
---|
| 598 | G4Vector3D G4SphericalSurface::Normal( const G4Vector3D& p ) const |
---|
| 599 | { // Return the Normal unit vector to the G4SphericalSurface at a point p on |
---|
| 600 | // (or nearly on) the G4SphericalSurface. |
---|
| 601 | G4Vector3D n = p - origin; |
---|
| 602 | G4double nmag = n.mag(); |
---|
| 603 | if ( nmag != 0.0 ) |
---|
| 604 | n = n / nmag; |
---|
| 605 | // If the point p happens to coincide with the origin (which is possible |
---|
| 606 | // if the radius is zero), set the Normal to the z-axis unit vector. |
---|
| 607 | else |
---|
| 608 | n = G4Vector3D( 0.0, 0.0, 1.0 ); |
---|
| 609 | return n; |
---|
| 610 | } |
---|
| 611 | */ |
---|
| 612 | |
---|
| 613 | |
---|
| 614 | G4Vector3D G4SphericalSurface::Normal( const G4Vector3D& p ) const |
---|
| 615 | { |
---|
| 616 | // Return the Normal unit vector to the G4SphericalSurface at a point p on |
---|
| 617 | // (or nearly on) the G4SphericalSurface. |
---|
| 618 | G4Vector3D n = G4Vector3D( p - origin ); |
---|
| 619 | G4double nmag = n.mag(); |
---|
| 620 | |
---|
| 621 | if ( nmag != 0.0 ) |
---|
| 622 | n = n * (1/ nmag); |
---|
| 623 | |
---|
| 624 | // If the point p happens to coincide with the origin (which is possible |
---|
| 625 | // if the radius is zero), set the Normal to the z-axis unit vector. |
---|
| 626 | else |
---|
| 627 | n = G4Vector3D( 0.0, 0.0, 1.0 ); |
---|
| 628 | |
---|
| 629 | return n; |
---|
| 630 | } |
---|
| 631 | |
---|
| 632 | |
---|
| 633 | G4Vector3D G4SphericalSurface::SurfaceNormal( const G4Point3D& p ) const |
---|
| 634 | { |
---|
| 635 | // Return the Normal unit vector to the G4SphericalSurface at a point p on |
---|
| 636 | // (or nearly on) the G4SphericalSurface. |
---|
| 637 | G4Vector3D n = G4Vector3D( p - origin ); |
---|
| 638 | G4double nmag = n.mag(); |
---|
| 639 | |
---|
| 640 | if ( nmag != 0.0 ) |
---|
| 641 | n = n * (1/ nmag); |
---|
| 642 | |
---|
| 643 | // If the point p happens to coincide with the origin (which is possible |
---|
| 644 | // if the radius is zero), set the Normal to the z-axis unit vector. |
---|
| 645 | else |
---|
| 646 | n = G4Vector3D( 0.0, 0.0, 1.0 ); |
---|
| 647 | |
---|
| 648 | return n; |
---|
| 649 | } |
---|
| 650 | |
---|
| 651 | |
---|
| 652 | G4int G4SphericalSurface::Inside ( const G4Vector3D& x ) const |
---|
| 653 | { |
---|
| 654 | // Return 0 if point x is outside G4SphericalSurface, 1 if Inside. |
---|
| 655 | // Outside means that the distance to the G4SphericalSurface would |
---|
| 656 | // be negative. |
---|
| 657 | // Use the HowNear function to calculate this distance. |
---|
| 658 | if ( HowNear( x ) >= 0.0 ) |
---|
| 659 | return 1; |
---|
| 660 | else |
---|
| 661 | return 0; |
---|
| 662 | } |
---|
| 663 | |
---|
| 664 | |
---|
| 665 | G4int G4SphericalSurface::WithinBoundary( const G4Vector3D& x ) const |
---|
| 666 | { |
---|
| 667 | // return 1 if point x is on the G4SphericalSurface, otherwise return zero |
---|
| 668 | // (x is assumed to lie on the surface of the G4SphericalSurface, so one |
---|
| 669 | // only checks the angular limits) |
---|
| 670 | G4Vector3D y_axis = G4Vector3D( z_axis.cross( x_axis ) ); |
---|
| 671 | |
---|
| 672 | // components of x in the local coordinate system of the G4SphericalSurface |
---|
| 673 | G4double px = x * x_axis; |
---|
| 674 | G4double py = x * y_axis; |
---|
| 675 | G4double pz = x * z_axis; |
---|
| 676 | |
---|
| 677 | // check if within polar angle limits |
---|
| 678 | G4double theta = std::acos( pz / x.mag() ); // acos in range 0 to PI |
---|
| 679 | |
---|
| 680 | // Normal case |
---|
| 681 | if ( theta_2 <= pi ) |
---|
| 682 | { |
---|
| 683 | if ( ( theta < theta_1 ) || ( theta > theta_2 ) ) |
---|
| 684 | return 0; |
---|
| 685 | } |
---|
| 686 | |
---|
| 687 | // this is for the case that theta_2 is greater than PI |
---|
| 688 | else |
---|
| 689 | { |
---|
| 690 | theta += pi; |
---|
| 691 | if ( ( theta < theta_1 ) || ( theta > theta_2 ) ) |
---|
| 692 | return 0; |
---|
| 693 | } |
---|
| 694 | |
---|
| 695 | // now check if within azimuthal angle limits |
---|
| 696 | G4double phi = std::atan2( py, px ); // atan2 in range -PI to PI |
---|
| 697 | |
---|
| 698 | if ( phi < 0.0 ) |
---|
| 699 | phi += twopi; |
---|
| 700 | |
---|
| 701 | // Normal case |
---|
| 702 | if ( ( phi >= phi_1 ) && ( phi <= phi_2 ) ) |
---|
| 703 | return 1; |
---|
| 704 | |
---|
| 705 | // this is for the case that phi_2 is greater than 2*PI |
---|
| 706 | phi += twopi; |
---|
| 707 | |
---|
| 708 | if ( ( phi >= phi_1 ) && ( phi <= phi_2 ) ) |
---|
| 709 | return 1; |
---|
| 710 | // get here if not within azimuthal limits |
---|
| 711 | |
---|
| 712 | return 0; |
---|
| 713 | } |
---|
| 714 | |
---|
| 715 | |
---|
| 716 | G4double G4SphericalSurface::Scale() const |
---|
| 717 | { |
---|
| 718 | // Returns the radius of a G4SphericalSurface unless it is zero, in which |
---|
| 719 | // case returns the arbitrary number 1.0. |
---|
| 720 | // Used for Scale-invariant tests of surface thickness. |
---|
| 721 | if ( radius == 0.0 ) |
---|
| 722 | return 1.0; |
---|
| 723 | else |
---|
| 724 | return radius; |
---|
| 725 | } |
---|
| 726 | |
---|
| 727 | |
---|
| 728 | G4double G4SphericalSurface::Area() const |
---|
| 729 | { |
---|
| 730 | // Returns the Area of a G4SphericalSurface |
---|
| 731 | return ( 2.0*( theta_2 - theta_1 )*( phi_2 - phi_1)*radius*radius/pi ); |
---|
| 732 | } |
---|
| 733 | |
---|
| 734 | |
---|
| 735 | void G4SphericalSurface::resize( G4double r, |
---|
| 736 | G4double ph1, G4double ph2, |
---|
| 737 | G4double th1, G4double th2 ) |
---|
| 738 | { |
---|
| 739 | // Resize the G4SphericalSurface to new radius r, new lower and upper |
---|
| 740 | // azimuthal angle limits ph1 and ph2, and new lower and upper polar |
---|
| 741 | // angle limits th1 and th2. |
---|
| 742 | |
---|
| 743 | // Require radius to be non-negative |
---|
| 744 | if ( r >= 0.0 ) |
---|
| 745 | radius = r; |
---|
| 746 | else |
---|
| 747 | { |
---|
| 748 | G4cerr << "Error in G4SphericalSurface::resize" |
---|
| 749 | << "--radius cannot be less than zero.\n" |
---|
| 750 | << "\tOriginal value of " << radius << " is retained.\n"; |
---|
| 751 | } |
---|
| 752 | |
---|
| 753 | // Require azimuthal angles to be within bounds |
---|
| 754 | |
---|
| 755 | if ( ( ph1 >= 0.0 ) && ( ph1 < twopi ) ) |
---|
| 756 | phi_1 = ph1; |
---|
| 757 | else |
---|
| 758 | { |
---|
| 759 | G4cerr << "Error in G4SphericalSurface::resize" |
---|
| 760 | << "--lower azimuthal limit out of range\n" |
---|
| 761 | << "\tOriginal value of " << phi_1 << " is retained.\n"; |
---|
| 762 | } |
---|
| 763 | |
---|
| 764 | if ( ( ph2 > phi_1 ) && ( ph2 <= ( phi_1 + twopi ) ) ) |
---|
| 765 | phi_2 = ph2; |
---|
| 766 | else |
---|
| 767 | { |
---|
| 768 | ph2 = ( phi_2 <= phi_1 ) ? ( phi_1 + FLT_EPSILO ) : phi_2; |
---|
| 769 | phi_2 = ph2; |
---|
| 770 | G4cerr << "Error in G4SphericalSurface::resize" |
---|
| 771 | << "--upper azimuthal limit out of range\n" |
---|
| 772 | << "\tValue of " << phi_2 << " is used.\n"; |
---|
| 773 | } |
---|
| 774 | |
---|
| 775 | // Require polar angles to be within bounds |
---|
| 776 | if ( ( th1 >= 0.0 ) && ( th1 < pi ) ) |
---|
| 777 | theta_1 = th1; |
---|
| 778 | else |
---|
| 779 | { |
---|
| 780 | G4cerr << "Error in G4SphericalSurface::resize" |
---|
| 781 | << "--lower polar limit out of range\n" |
---|
| 782 | << "\tOriginal value of " << theta_1 << " is retained.\n"; |
---|
| 783 | } |
---|
| 784 | |
---|
| 785 | if ( ( th2 > theta_1 ) && ( th2 <= ( theta_1 + pi ) ) ) |
---|
| 786 | theta_2 = th2; |
---|
| 787 | else |
---|
| 788 | { |
---|
| 789 | th2 = ( theta_2 <= theta_1 ) ? ( theta_1 + FLT_EPSILO ) : theta_2; |
---|
| 790 | theta_2 = th2; |
---|
| 791 | G4cerr << "Error in G4SphericalSurface::resize" |
---|
| 792 | << "--upper polar limit out of range\n" |
---|
| 793 | << "\tValue of " << theta_2 << " is used.\n"; |
---|
| 794 | } |
---|
| 795 | } |
---|
| 796 | |
---|
| 797 | |
---|
| 798 | /* |
---|
| 799 | void G4SphericalSurface::rotate( G4double alpha, G4double beta, |
---|
| 800 | G4double gamma, G4ThreeMat& m, G4int inverse ) |
---|
| 801 | { // rotate G4SphericalSurface first about global x_axis by angle alpha, |
---|
| 802 | // second about global y-axis by angle beta, |
---|
| 803 | // and third about global z_axis by angle gamma |
---|
| 804 | // by creating and using G4ThreeMat objects in Surface::rotate |
---|
| 805 | // angles are assumed to be given in radians |
---|
| 806 | // if inverse is non-zero, the order of rotations is reversed |
---|
| 807 | // the axis is rotated here, the origin is rotated by calling |
---|
| 808 | // Surface::rotate |
---|
| 809 | G4Surface::rotate( alpha, beta, gamma, m, inverse ); |
---|
| 810 | x_axis = m * x_axis; |
---|
| 811 | z_axis = m * z_axis; |
---|
| 812 | } |
---|
| 813 | */ |
---|
| 814 | |
---|
| 815 | |
---|
| 816 | /* |
---|
| 817 | void G4SphericalSurface::rotate( G4double alpha, G4double beta, |
---|
| 818 | G4double gamma, G4int inverse ) |
---|
| 819 | { // rotate G4SphericalSurface first about global x_axis by angle alpha, |
---|
| 820 | // second about global y-axis by angle beta, |
---|
| 821 | // and third about global z_axis by angle gamma |
---|
| 822 | // by creating and using G4ThreeMat objects in Surface::rotate |
---|
| 823 | // angles are assumed to be given in radians |
---|
| 824 | // if inverse is non-zero, the order of rotations is reversed |
---|
| 825 | // the axis is rotated here, the origin is rotated by calling |
---|
| 826 | // Surface::rotate |
---|
| 827 | G4ThreeMat m; |
---|
| 828 | G4Surface::rotate( alpha, beta, gamma, m, inverse ); |
---|
| 829 | x_axis = m * x_axis; |
---|
| 830 | z_axis = m * z_axis; |
---|
| 831 | } |
---|
| 832 | */ |
---|
| 833 | |
---|
| 834 | |
---|
| 835 | /* |
---|
| 836 | G4double G4SphericalSurface::gropeAlongHelix( const Helix* hx ) const |
---|
| 837 | { // Grope for a solution of a Helix intersecting a G4SphericalSurface. |
---|
| 838 | // This function returns the turning angle (in radians) where the |
---|
| 839 | // intersection occurs with only positive values allowed, or -1.0 if |
---|
| 840 | // no intersection is found. |
---|
| 841 | // The idea is to start at the beginning of the Helix, then take steps |
---|
| 842 | // of some fraction of a turn. If at the end of a Step, the current position |
---|
| 843 | // along the Helix and the previous position are on opposite sides of the |
---|
| 844 | // G4SphericalSurface, then the solution must lie somewhere in between. |
---|
| 845 | G4int one_over_f = 8; // one over fraction of a turn to go in each Step |
---|
| 846 | G4double turn_angle = 0.0; |
---|
| 847 | G4double dist_along = 0.0; |
---|
| 848 | G4double d_new; |
---|
| 849 | G4double fk = 1.0 / G4double( one_over_f ); |
---|
| 850 | G4double scal = Scale(); |
---|
| 851 | G4double d_old = HowNear( hx->position( dist_along ) ); |
---|
| 852 | G4double rh = hx->GetRadius(); // radius of Helix |
---|
| 853 | G4Vector3D prp = hx->getPerp(); // perpendicular vector |
---|
| 854 | G4double prpmag = prp.mag(); |
---|
| 855 | G4double rhp = rh / prpmag; |
---|
| 856 | G4int max_iter = one_over_f * HELIX_MAX_TURNS; |
---|
| 857 | // Take up to a user-settable number of turns along the Helix, |
---|
| 858 | // groping for an intersection point. |
---|
| 859 | for ( G4int k = 1; k < max_iter; k++ ) { |
---|
| 860 | turn_angle = twopi * k / one_over_f; |
---|
| 861 | dist_along = turn_angle * std::fabs( rhp ); |
---|
| 862 | d_new = HowNear( hx->position( dist_along ) ); |
---|
| 863 | if ( ( d_old < 0.0 && d_new > 0.0 ) || |
---|
| 864 | ( d_old > 0.0 && d_new < 0.0 ) ) { |
---|
| 865 | d_old = d_new; |
---|
| 866 | // Old and new points are on opposite sides of the G4SphericalSurface, therefore |
---|
| 867 | // a solution lies in between, use a binary search to pin the point down |
---|
| 868 | // to the surface precision, but don't do more than 50 iterations. |
---|
| 869 | G4int itr = 0; |
---|
| 870 | while ( std::fabs( d_new / scal ) > SURFACE_PRECISION ) { |
---|
| 871 | itr++; |
---|
| 872 | if ( itr > 50 ) |
---|
| 873 | return turn_angle; |
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| 874 | turn_angle -= fk * pi; |
---|
| 875 | dist_along = turn_angle * std::fabs( rhp ); |
---|
| 876 | d_new = HowNear( hx->position( dist_along ) ); |
---|
| 877 | if ( ( d_old < 0.0 && d_new > 0.0 ) || |
---|
| 878 | ( d_old > 0.0 && d_new < 0.0 ) ) |
---|
| 879 | fk *= -0.5; |
---|
| 880 | else |
---|
| 881 | fk *= 0.5; |
---|
| 882 | d_old = d_new; |
---|
| 883 | } // end of while loop |
---|
| 884 | return turn_angle; // this is the best solution |
---|
| 885 | } // end of if condition |
---|
| 886 | } // end of for loop |
---|
| 887 | // Get here only if no solution is found, so return -1.0 to indicate that. |
---|
| 888 | return -1.0; |
---|
| 889 | } |
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| 890 | */ |
---|