[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: G4PolyconeSide.cc,v 1.17 2007/08/13 10:33:04 gcosmo Exp $ |
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| 28 | // GEANT4 tag $Name: $ |
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| 29 | // |
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| 30 | // |
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| 31 | // -------------------------------------------------------------------- |
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| 32 | // GEANT 4 class source file |
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| 33 | // |
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| 34 | // |
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| 35 | // G4PolyconeSide.cc |
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| 36 | // |
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| 37 | // Implementation of the face representing one conical side of a polycone |
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| 38 | // |
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| 39 | // -------------------------------------------------------------------- |
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| 40 | |
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| 41 | #include "G4PolyconeSide.hh" |
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| 42 | #include "G4IntersectingCone.hh" |
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| 43 | #include "G4ClippablePolygon.hh" |
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| 44 | #include "G4AffineTransform.hh" |
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| 45 | #include "meshdefs.hh" |
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| 46 | #include "G4SolidExtentList.hh" |
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| 47 | #include "G4GeometryTolerance.hh" |
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| 48 | |
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| 49 | // |
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| 50 | // Constructor |
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| 51 | // |
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| 52 | // Values for r1,z1 and r2,z2 should be specified in clockwise |
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| 53 | // order in (r,z). |
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| 54 | // |
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| 55 | G4PolyconeSide::G4PolyconeSide( const G4PolyconeSideRZ *prevRZ, |
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| 56 | const G4PolyconeSideRZ *tail, |
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| 57 | const G4PolyconeSideRZ *head, |
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| 58 | const G4PolyconeSideRZ *nextRZ, |
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| 59 | G4double thePhiStart, |
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| 60 | G4double theDeltaPhi, |
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| 61 | G4bool thePhiIsOpen, |
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| 62 | G4bool isAllBehind ) |
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| 63 | : ncorners(0), corners(0) |
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| 64 | { |
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| 65 | kCarTolerance = G4GeometryTolerance::GetInstance()->GetSurfaceTolerance(); |
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| 66 | |
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| 67 | // |
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| 68 | // Record values |
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| 69 | // |
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| 70 | r[0] = tail->r; z[0] = tail->z; |
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| 71 | r[1] = head->r; z[1] = head->z; |
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| 72 | |
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| 73 | phiIsOpen = thePhiIsOpen; |
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| 74 | if (phiIsOpen) |
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| 75 | { |
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| 76 | deltaPhi = theDeltaPhi; |
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| 77 | startPhi = thePhiStart; |
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| 78 | |
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| 79 | // |
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| 80 | // Set phi values to our conventions |
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| 81 | // |
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| 82 | while (deltaPhi < 0.0) deltaPhi += twopi; |
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| 83 | while (startPhi < 0.0) startPhi += twopi; |
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| 84 | |
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| 85 | // |
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| 86 | // Calculate corner coordinates |
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| 87 | // |
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| 88 | ncorners = 4; |
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| 89 | corners = new G4ThreeVector[ncorners]; |
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| 90 | |
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| 91 | corners[0] = G4ThreeVector( tail->r*std::cos(startPhi), |
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| 92 | tail->r*std::sin(startPhi), tail->z ); |
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| 93 | corners[1] = G4ThreeVector( head->r*std::cos(startPhi), |
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| 94 | head->r*std::sin(startPhi), head->z ); |
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| 95 | corners[2] = G4ThreeVector( tail->r*std::cos(startPhi+deltaPhi), |
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| 96 | tail->r*std::sin(startPhi+deltaPhi), tail->z ); |
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| 97 | corners[3] = G4ThreeVector( head->r*std::cos(startPhi+deltaPhi), |
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| 98 | head->r*std::sin(startPhi+deltaPhi), head->z ); |
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| 99 | } |
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| 100 | else |
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| 101 | { |
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| 102 | deltaPhi = twopi; |
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| 103 | startPhi = 0.0; |
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| 104 | } |
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| 105 | |
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| 106 | allBehind = isAllBehind; |
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| 107 | |
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| 108 | // |
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| 109 | // Make our intersecting cone |
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| 110 | // |
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| 111 | cone = new G4IntersectingCone( r, z ); |
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| 112 | |
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| 113 | // |
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| 114 | // Calculate vectors in r,z space |
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| 115 | // |
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| 116 | rS = r[1]-r[0]; zS = z[1]-z[0]; |
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| 117 | length = std::sqrt( rS*rS + zS*zS); |
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| 118 | rS /= length; zS /= length; |
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| 119 | |
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| 120 | rNorm = +zS; |
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| 121 | zNorm = -rS; |
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| 122 | |
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| 123 | G4double lAdj; |
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| 124 | |
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| 125 | prevRS = r[0]-prevRZ->r; |
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| 126 | prevZS = z[0]-prevRZ->z; |
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| 127 | lAdj = std::sqrt( prevRS*prevRS + prevZS*prevZS ); |
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| 128 | prevRS /= lAdj; |
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| 129 | prevZS /= lAdj; |
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| 130 | |
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| 131 | rNormEdge[0] = rNorm + prevZS; |
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| 132 | zNormEdge[0] = zNorm - prevRS; |
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| 133 | lAdj = std::sqrt( rNormEdge[0]*rNormEdge[0] + zNormEdge[0]*zNormEdge[0] ); |
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| 134 | rNormEdge[0] /= lAdj; |
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| 135 | zNormEdge[0] /= lAdj; |
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| 136 | |
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| 137 | nextRS = nextRZ->r-r[1]; |
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| 138 | nextZS = nextRZ->z-z[1]; |
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| 139 | lAdj = std::sqrt( nextRS*nextRS + nextZS*nextZS ); |
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| 140 | nextRS /= lAdj; |
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| 141 | nextZS /= lAdj; |
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| 142 | |
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| 143 | rNormEdge[1] = rNorm + nextZS; |
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| 144 | zNormEdge[1] = zNorm - nextRS; |
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| 145 | lAdj = std::sqrt( rNormEdge[1]*rNormEdge[1] + zNormEdge[1]*zNormEdge[1] ); |
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| 146 | rNormEdge[1] /= lAdj; |
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| 147 | zNormEdge[1] /= lAdj; |
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| 148 | } |
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| 149 | |
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| 150 | |
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| 151 | // |
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| 152 | // Fake default constructor - sets only member data and allocates memory |
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| 153 | // for usage restricted to object persistency. |
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| 154 | // |
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| 155 | G4PolyconeSide::G4PolyconeSide( __void__& ) |
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| 156 | : phiIsOpen(false), cone(0), ncorners(0), corners(0) |
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| 157 | { |
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| 158 | } |
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| 159 | |
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| 160 | |
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| 161 | // |
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| 162 | // Destructor |
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| 163 | // |
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| 164 | G4PolyconeSide::~G4PolyconeSide() |
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| 165 | { |
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| 166 | delete cone; |
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| 167 | if (phiIsOpen) delete [] corners; |
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| 168 | } |
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| 169 | |
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| 170 | |
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| 171 | // |
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| 172 | // Copy constructor |
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| 173 | // |
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| 174 | G4PolyconeSide::G4PolyconeSide( const G4PolyconeSide &source ) |
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| 175 | : G4VCSGface() |
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| 176 | { |
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| 177 | CopyStuff( source ); |
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| 178 | } |
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| 179 | |
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| 180 | |
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| 181 | // |
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| 182 | // Assignment operator |
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| 183 | // |
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| 184 | G4PolyconeSide& G4PolyconeSide::operator=( const G4PolyconeSide &source ) |
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| 185 | { |
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| 186 | if (this == &source) return *this; |
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| 187 | |
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| 188 | delete cone; |
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| 189 | if (phiIsOpen) delete [] corners; |
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| 190 | |
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| 191 | CopyStuff( source ); |
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| 192 | |
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| 193 | return *this; |
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| 194 | } |
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| 195 | |
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| 196 | |
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| 197 | // |
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| 198 | // CopyStuff |
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| 199 | // |
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| 200 | void G4PolyconeSide::CopyStuff( const G4PolyconeSide &source ) |
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| 201 | { |
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| 202 | r[0] = source.r[0]; |
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| 203 | r[1] = source.r[1]; |
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| 204 | z[0] = source.z[0]; |
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| 205 | z[1] = source.z[1]; |
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| 206 | |
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| 207 | startPhi = source.startPhi; |
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| 208 | deltaPhi = source.deltaPhi; |
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| 209 | phiIsOpen = source.phiIsOpen; |
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| 210 | allBehind = source.allBehind; |
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| 211 | |
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| 212 | kCarTolerance = source.kCarTolerance; |
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| 213 | |
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| 214 | cone = new G4IntersectingCone( *source.cone ); |
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| 215 | |
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| 216 | rNorm = source.rNorm; |
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| 217 | zNorm = source.zNorm; |
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| 218 | rS = source.rS; |
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| 219 | zS = source.zS; |
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| 220 | length = source.length; |
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| 221 | prevRS = source.prevRS; |
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| 222 | prevZS = source.prevZS; |
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| 223 | nextRS = source.nextRS; |
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| 224 | nextZS = source.nextZS; |
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| 225 | |
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| 226 | rNormEdge[0] = source.rNormEdge[0]; |
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| 227 | rNormEdge[1] = source.rNormEdge[1]; |
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| 228 | zNormEdge[0] = source.zNormEdge[0]; |
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| 229 | zNormEdge[1] = source.zNormEdge[1]; |
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| 230 | |
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| 231 | if (phiIsOpen) |
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| 232 | { |
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| 233 | ncorners = 4; |
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| 234 | corners = new G4ThreeVector[ncorners]; |
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| 235 | |
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| 236 | corners[0] = source.corners[0]; |
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| 237 | corners[1] = source.corners[1]; |
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| 238 | corners[2] = source.corners[2]; |
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| 239 | corners[3] = source.corners[3]; |
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| 240 | } |
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| 241 | } |
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| 242 | |
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| 243 | |
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| 244 | // |
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| 245 | // Intersect |
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| 246 | // |
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| 247 | G4bool G4PolyconeSide::Intersect( const G4ThreeVector &p, |
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| 248 | const G4ThreeVector &v, |
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| 249 | G4bool outgoing, |
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| 250 | G4double surfTolerance, |
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| 251 | G4double &distance, |
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| 252 | G4double &distFromSurface, |
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| 253 | G4ThreeVector &normal, |
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| 254 | G4bool &isAllBehind ) |
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| 255 | { |
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| 256 | G4double s1, s2; |
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| 257 | G4double normSign = outgoing ? +1 : -1; |
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| 258 | |
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| 259 | isAllBehind = allBehind; |
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| 260 | |
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| 261 | // |
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| 262 | // Check for two possible intersections |
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| 263 | // |
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| 264 | G4int nside = cone->LineHitsCone( p, v, &s1, &s2 ); |
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| 265 | if (nside == 0) return false; |
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| 266 | |
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| 267 | // |
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| 268 | // Check the first side first, since it is (supposed to be) closest |
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| 269 | // |
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| 270 | G4ThreeVector hit = p + s1*v; |
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| 271 | |
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| 272 | if (PointOnCone( hit, normSign, p, v, normal )) |
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| 273 | { |
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| 274 | // |
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| 275 | // Good intersection! What about the normal? |
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| 276 | // |
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| 277 | if (normSign*v.dot(normal) > 0) |
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| 278 | { |
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| 279 | // |
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| 280 | // We have a valid intersection, but it could very easily |
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| 281 | // be behind the point. To decide if we tolerate this, |
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| 282 | // we have to see if the point p is on the surface near |
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| 283 | // the intersecting point. |
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| 284 | // |
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| 285 | // What does it mean exactly for the point p to be "near" |
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| 286 | // the intersection? It means that if we draw a line from |
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| 287 | // p to the hit, the line remains entirely within the |
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| 288 | // tolerance bounds of the cone. To test this, we can |
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| 289 | // ask if the normal is correct near p. |
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| 290 | // |
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| 291 | G4double pr = p.perp(); |
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| 292 | if (pr < DBL_MIN) pr = DBL_MIN; |
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| 293 | G4ThreeVector pNormal( rNorm*p.x()/pr, rNorm*p.y()/pr, zNorm ); |
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| 294 | if (normSign*v.dot(pNormal) > 0) |
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| 295 | { |
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| 296 | // |
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| 297 | // p and intersection in same hemisphere |
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| 298 | // |
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| 299 | G4double distOutside2; |
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| 300 | distFromSurface = -normSign*DistanceAway( p, false, distOutside2 ); |
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| 301 | if (distOutside2 < surfTolerance*surfTolerance) |
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| 302 | { |
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| 303 | if (distFromSurface > -surfTolerance) |
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| 304 | { |
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| 305 | // |
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| 306 | // We are just inside or away from the |
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| 307 | // surface. Accept *any* value of distance. |
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| 308 | // |
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| 309 | distance = s1; |
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| 310 | return true; |
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| 311 | } |
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| 312 | } |
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| 313 | } |
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| 314 | else |
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| 315 | distFromSurface = s1; |
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| 316 | |
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| 317 | // |
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| 318 | // Accept positive distances |
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| 319 | // |
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| 320 | if (s1 > 0) |
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| 321 | { |
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| 322 | distance = s1; |
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| 323 | return true; |
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| 324 | } |
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| 325 | } |
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| 326 | } |
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| 327 | |
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| 328 | if (nside==1) return false; |
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| 329 | |
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| 330 | // |
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| 331 | // Well, try the second hit |
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| 332 | // |
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| 333 | hit = p + s2*v; |
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| 334 | |
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| 335 | if (PointOnCone( hit, normSign, p, v, normal )) |
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| 336 | { |
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| 337 | // |
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| 338 | // Good intersection! What about the normal? |
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| 339 | // |
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| 340 | if (normSign*v.dot(normal) > 0) |
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| 341 | { |
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| 342 | G4double pr = p.perp(); |
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| 343 | if (pr < DBL_MIN) pr = DBL_MIN; |
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| 344 | G4ThreeVector pNormal( rNorm*p.x()/pr, rNorm*p.y()/pr, zNorm ); |
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| 345 | if (normSign*v.dot(pNormal) > 0) |
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| 346 | { |
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| 347 | G4double distOutside2; |
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| 348 | distFromSurface = -normSign*DistanceAway( p, false, distOutside2 ); |
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| 349 | if (distOutside2 < surfTolerance*surfTolerance) |
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| 350 | { |
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| 351 | if (distFromSurface > -surfTolerance) |
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| 352 | { |
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| 353 | distance = s2; |
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| 354 | return true; |
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| 355 | } |
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| 356 | } |
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| 357 | } |
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| 358 | else |
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| 359 | distFromSurface = s2; |
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| 360 | |
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| 361 | if (s2 > 0) |
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| 362 | { |
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| 363 | distance = s2; |
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| 364 | return true; |
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| 365 | } |
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| 366 | } |
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| 367 | } |
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| 368 | |
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| 369 | // |
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| 370 | // Better luck next time |
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| 371 | // |
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| 372 | return false; |
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| 373 | } |
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| 374 | |
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| 375 | |
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| 376 | G4double G4PolyconeSide::Distance( const G4ThreeVector &p, G4bool outgoing ) |
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| 377 | { |
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| 378 | G4double normSign = outgoing ? -1 : +1; |
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| 379 | G4double distFrom, distOut2; |
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| 380 | |
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| 381 | // |
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| 382 | // We have two tries for each hemisphere. Try the closest first. |
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| 383 | // |
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| 384 | distFrom = normSign*DistanceAway( p, false, distOut2 ); |
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| 385 | if (distFrom > -0.5*kCarTolerance ) |
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| 386 | { |
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| 387 | // |
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| 388 | // Good answer |
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| 389 | // |
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| 390 | if (distOut2 > 0) |
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| 391 | return std::sqrt( distFrom*distFrom + distOut2 ); |
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| 392 | else |
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| 393 | return std::fabs(distFrom); |
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| 394 | } |
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| 395 | |
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| 396 | // |
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| 397 | // Try second side. |
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| 398 | // |
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| 399 | distFrom = normSign*DistanceAway( p, true, distOut2 ); |
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| 400 | if (distFrom > -0.5*kCarTolerance) |
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| 401 | { |
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| 402 | |
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| 403 | if (distOut2 > 0) |
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| 404 | return std::sqrt( distFrom*distFrom + distOut2 ); |
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| 405 | else |
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| 406 | return std::fabs(distFrom); |
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| 407 | } |
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| 408 | |
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| 409 | return kInfinity; |
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| 410 | } |
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| 411 | |
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| 412 | |
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| 413 | // |
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| 414 | // Inside |
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| 415 | // |
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| 416 | EInside G4PolyconeSide::Inside( const G4ThreeVector &p, |
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| 417 | G4double tolerance, |
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| 418 | G4double *bestDistance ) |
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| 419 | { |
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| 420 | // |
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| 421 | // Check both sides |
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| 422 | // |
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| 423 | G4double distFrom[2], distOut2[2], dist2[2]; |
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| 424 | G4double edgeRZnorm[2]; |
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| 425 | |
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| 426 | distFrom[0] = DistanceAway( p, false, distOut2[0], edgeRZnorm ); |
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| 427 | distFrom[1] = DistanceAway( p, true, distOut2[1], edgeRZnorm+1 ); |
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| 428 | |
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| 429 | dist2[0] = distFrom[0]*distFrom[0] + distOut2[0]; |
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| 430 | dist2[1] = distFrom[1]*distFrom[1] + distOut2[1]; |
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| 431 | |
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| 432 | // |
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| 433 | // Who's closest? |
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| 434 | // |
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| 435 | G4int i = std::fabs(dist2[0]) < std::fabs(dist2[1]) ? 0 : 1; |
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| 436 | |
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| 437 | *bestDistance = std::sqrt( dist2[i] ); |
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| 438 | |
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| 439 | // |
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| 440 | // Okay then, inside or out? |
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| 441 | // |
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| 442 | if ( (std::fabs(edgeRZnorm[i]) < tolerance) |
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| 443 | && (distOut2[i] < tolerance*tolerance) ) |
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| 444 | return kSurface; |
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| 445 | else if (edgeRZnorm[i] < 0) |
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| 446 | return kInside; |
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| 447 | else |
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| 448 | return kOutside; |
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| 449 | } |
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| 450 | |
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| 451 | |
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| 452 | // |
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| 453 | // Normal |
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| 454 | // |
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| 455 | G4ThreeVector G4PolyconeSide::Normal( const G4ThreeVector &p, |
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| 456 | G4double *bestDistance ) |
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| 457 | { |
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| 458 | if (p == G4ThreeVector(0.,0.,0.)) { return p; } |
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| 459 | |
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| 460 | G4ThreeVector dFrom; |
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| 461 | G4double dOut2; |
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| 462 | |
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| 463 | dFrom = DistanceAway( p, false, dOut2 ); |
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| 464 | |
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| 465 | *bestDistance = std::sqrt( dFrom*dFrom + dOut2 ); |
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| 466 | |
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| 467 | G4double rad = p.perp(); |
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| 468 | return G4ThreeVector( rNorm*p.x()/rad, rNorm*p.y()/rad, zNorm ); |
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| 469 | } |
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| 470 | |
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| 471 | |
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| 472 | // |
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| 473 | // Extent |
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| 474 | // |
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| 475 | G4double G4PolyconeSide::Extent( const G4ThreeVector axis ) |
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| 476 | { |
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| 477 | if (axis.perp2() < DBL_MIN) |
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| 478 | { |
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| 479 | // |
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| 480 | // Special case |
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| 481 | // |
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| 482 | return axis.z() < 0 ? -cone->ZLo() : cone->ZHi(); |
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| 483 | } |
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| 484 | |
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| 485 | // |
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| 486 | // Is the axis pointing inside our phi gap? |
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| 487 | // |
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| 488 | if (phiIsOpen) |
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| 489 | { |
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| 490 | G4double phi = axis.phi(); |
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| 491 | while( phi < startPhi ) phi += twopi; |
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| 492 | |
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| 493 | if (phi > deltaPhi+startPhi) |
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| 494 | { |
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| 495 | // |
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| 496 | // Yeah, looks so. Make four three vectors defining the phi |
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| 497 | // opening |
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| 498 | // |
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| 499 | G4double cosP = std::cos(startPhi), sinP = std::sin(startPhi); |
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| 500 | G4ThreeVector a( r[0]*cosP, r[0]*sinP, z[0] ); |
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| 501 | G4ThreeVector b( r[1]*cosP, r[1]*sinP, z[1] ); |
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| 502 | cosP = std::cos(startPhi+deltaPhi); sinP = std::sin(startPhi+deltaPhi); |
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| 503 | G4ThreeVector c( r[0]*cosP, r[0]*sinP, z[0] ); |
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| 504 | G4ThreeVector d( r[1]*cosP, r[1]*sinP, z[1] ); |
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| 505 | |
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| 506 | G4double ad = axis.dot(a), |
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| 507 | bd = axis.dot(b), |
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| 508 | cd = axis.dot(c), |
---|
| 509 | dd = axis.dot(d); |
---|
| 510 | |
---|
| 511 | if (bd > ad) ad = bd; |
---|
| 512 | if (cd > ad) ad = cd; |
---|
| 513 | if (dd > ad) ad = dd; |
---|
| 514 | |
---|
| 515 | return ad; |
---|
| 516 | } |
---|
| 517 | } |
---|
| 518 | |
---|
| 519 | // |
---|
| 520 | // Check either end |
---|
| 521 | // |
---|
| 522 | G4double aPerp = axis.perp(); |
---|
| 523 | |
---|
| 524 | G4double a = aPerp*r[0] + axis.z()*z[0]; |
---|
| 525 | G4double b = aPerp*r[1] + axis.z()*z[1]; |
---|
| 526 | |
---|
| 527 | if (b > a) a = b; |
---|
| 528 | |
---|
| 529 | return a; |
---|
| 530 | } |
---|
| 531 | |
---|
| 532 | |
---|
| 533 | |
---|
| 534 | // |
---|
| 535 | // CalculateExtent |
---|
| 536 | // |
---|
| 537 | // See notes in G4VCSGface |
---|
| 538 | // |
---|
| 539 | void G4PolyconeSide::CalculateExtent( const EAxis axis, |
---|
| 540 | const G4VoxelLimits &voxelLimit, |
---|
| 541 | const G4AffineTransform &transform, |
---|
| 542 | G4SolidExtentList &extentList ) |
---|
| 543 | { |
---|
| 544 | G4ClippablePolygon polygon; |
---|
| 545 | |
---|
| 546 | // |
---|
| 547 | // Here we will approximate (ala G4Cons) and divide our conical section |
---|
| 548 | // into segments, like G4Polyhedra. When doing so, the radius |
---|
| 549 | // is extented far enough such that the segments always lie |
---|
| 550 | // just outside the surface of the conical section we are |
---|
| 551 | // approximating. |
---|
| 552 | // |
---|
| 553 | |
---|
| 554 | // |
---|
| 555 | // Choose phi size of our segment(s) based on constants as |
---|
| 556 | // defined in meshdefs.hh |
---|
| 557 | // |
---|
| 558 | G4int numPhi = (G4int)(deltaPhi/kMeshAngleDefault) + 1; |
---|
| 559 | if (numPhi < kMinMeshSections) |
---|
| 560 | numPhi = kMinMeshSections; |
---|
| 561 | else if (numPhi > kMaxMeshSections) |
---|
| 562 | numPhi = kMaxMeshSections; |
---|
| 563 | |
---|
| 564 | G4double sigPhi = deltaPhi/numPhi; |
---|
| 565 | |
---|
| 566 | // |
---|
| 567 | // Determine radius factor to keep segments outside |
---|
| 568 | // |
---|
| 569 | G4double rFudge = 1.0/std::cos(0.5*sigPhi); |
---|
| 570 | |
---|
| 571 | // |
---|
| 572 | // Decide which radius to use on each end of the side, |
---|
| 573 | // and whether a transition mesh is required |
---|
| 574 | // |
---|
| 575 | // {r0,z0} - Beginning of this side |
---|
| 576 | // {r1,z1} - Ending of this side |
---|
| 577 | // {r2,z0} - Beginning of transition piece connecting previous |
---|
| 578 | // side (and ends at beginning of this side) |
---|
| 579 | // |
---|
| 580 | // So, order is 2 --> 0 --> 1. |
---|
| 581 | // ------- |
---|
| 582 | // |
---|
| 583 | // r2 < 0 indicates that no transition piece is required |
---|
| 584 | // |
---|
| 585 | G4double r0, r1, r2, z0, z1; |
---|
| 586 | |
---|
| 587 | r2 = -1; // By default: no transition piece |
---|
| 588 | |
---|
| 589 | if (rNorm < -DBL_MIN) |
---|
| 590 | { |
---|
| 591 | // |
---|
| 592 | // This side faces *inward*, and so our mesh has |
---|
| 593 | // the same radius |
---|
| 594 | // |
---|
| 595 | r1 = r[1]; |
---|
| 596 | z1 = z[1]; |
---|
| 597 | z0 = z[0]; |
---|
| 598 | r0 = r[0]; |
---|
| 599 | |
---|
| 600 | r2 = -1; |
---|
| 601 | |
---|
| 602 | if (prevZS > DBL_MIN) |
---|
| 603 | { |
---|
| 604 | // |
---|
| 605 | // The previous side is facing outwards |
---|
| 606 | // |
---|
| 607 | if ( prevRS*zS - prevZS*rS > 0 ) |
---|
| 608 | { |
---|
| 609 | // |
---|
| 610 | // Transition was convex: build transition piece |
---|
| 611 | // |
---|
| 612 | if (r[0] > DBL_MIN) r2 = r[0]*rFudge; |
---|
| 613 | } |
---|
| 614 | else |
---|
| 615 | { |
---|
| 616 | // |
---|
| 617 | // Transition was concave: short this side |
---|
| 618 | // |
---|
| 619 | FindLineIntersect( z0, r0, zS, rS, |
---|
| 620 | z0, r0*rFudge, prevZS, prevRS*rFudge, z0, r0 ); |
---|
| 621 | } |
---|
| 622 | } |
---|
| 623 | |
---|
| 624 | if ( nextZS > DBL_MIN && (rS*nextZS - zS*nextRS < 0) ) |
---|
| 625 | { |
---|
| 626 | // |
---|
| 627 | // The next side is facing outwards, forming a |
---|
| 628 | // concave transition: short this side |
---|
| 629 | // |
---|
| 630 | FindLineIntersect( z1, r1, zS, rS, |
---|
| 631 | z1, r1*rFudge, nextZS, nextRS*rFudge, z1, r1 ); |
---|
| 632 | } |
---|
| 633 | } |
---|
| 634 | else if (rNorm > DBL_MIN) |
---|
| 635 | { |
---|
| 636 | // |
---|
| 637 | // This side faces *outward* and is given a boost to |
---|
| 638 | // it radius |
---|
| 639 | // |
---|
| 640 | r0 = r[0]*rFudge; |
---|
| 641 | z0 = z[0]; |
---|
| 642 | r1 = r[1]*rFudge; |
---|
| 643 | z1 = z[1]; |
---|
| 644 | |
---|
| 645 | if (prevZS < -DBL_MIN) |
---|
| 646 | { |
---|
| 647 | // |
---|
| 648 | // The previous side is facing inwards |
---|
| 649 | // |
---|
| 650 | if ( prevRS*zS - prevZS*rS > 0 ) |
---|
| 651 | { |
---|
| 652 | // |
---|
| 653 | // Transition was convex: build transition piece |
---|
| 654 | // |
---|
| 655 | if (r[0] > DBL_MIN) r2 = r[0]; |
---|
| 656 | } |
---|
| 657 | else |
---|
| 658 | { |
---|
| 659 | // |
---|
| 660 | // Transition was concave: short this side |
---|
| 661 | // |
---|
| 662 | FindLineIntersect( z0, r0, zS, rS*rFudge, |
---|
| 663 | z0, r[0], prevZS, prevRS, z0, r0 ); |
---|
| 664 | } |
---|
| 665 | } |
---|
| 666 | |
---|
| 667 | if ( nextZS < -DBL_MIN && (rS*nextZS - zS*nextRS < 0) ) |
---|
| 668 | { |
---|
| 669 | // |
---|
| 670 | // The next side is facing inwards, forming a |
---|
| 671 | // concave transition: short this side |
---|
| 672 | // |
---|
| 673 | FindLineIntersect( z1, r1, zS, rS*rFudge, |
---|
| 674 | z1, r[1], nextZS, nextRS, z1, r1 ); |
---|
| 675 | } |
---|
| 676 | } |
---|
| 677 | else |
---|
| 678 | { |
---|
| 679 | // |
---|
| 680 | // This side is perpendicular to the z axis (is a disk) |
---|
| 681 | // |
---|
| 682 | // Whether or not r0 needs a rFudge factor depends |
---|
| 683 | // on the normal of the previous edge. Similar with r1 |
---|
| 684 | // and the next edge. No transition piece is required. |
---|
| 685 | // |
---|
| 686 | r0 = r[0]; |
---|
| 687 | r1 = r[1]; |
---|
| 688 | z0 = z[0]; |
---|
| 689 | z1 = z[1]; |
---|
| 690 | |
---|
| 691 | if (prevZS > DBL_MIN) r0 *= rFudge; |
---|
| 692 | if (nextZS > DBL_MIN) r1 *= rFudge; |
---|
| 693 | } |
---|
| 694 | |
---|
| 695 | // |
---|
| 696 | // Loop |
---|
| 697 | // |
---|
| 698 | G4double phi = startPhi, |
---|
| 699 | cosPhi = std::cos(phi), |
---|
| 700 | sinPhi = std::sin(phi); |
---|
| 701 | |
---|
| 702 | G4ThreeVector v0( r0*cosPhi, r0*sinPhi, z0 ), |
---|
| 703 | v1( r1*cosPhi, r1*sinPhi, z1 ), |
---|
| 704 | v2, w0, w1, w2; |
---|
| 705 | transform.ApplyPointTransform( v0 ); |
---|
| 706 | transform.ApplyPointTransform( v1 ); |
---|
| 707 | |
---|
| 708 | if (r2 >= 0) |
---|
| 709 | { |
---|
| 710 | v2 = G4ThreeVector( r2*cosPhi, r2*sinPhi, z0 ); |
---|
| 711 | transform.ApplyPointTransform( v2 ); |
---|
| 712 | } |
---|
| 713 | |
---|
| 714 | do |
---|
| 715 | { |
---|
| 716 | phi += sigPhi; |
---|
| 717 | if (numPhi == 1) phi = startPhi+deltaPhi; // Try to avoid roundoff |
---|
| 718 | cosPhi = std::cos(phi), |
---|
| 719 | sinPhi = std::sin(phi); |
---|
| 720 | |
---|
| 721 | w0 = G4ThreeVector( r0*cosPhi, r0*sinPhi, z0 ); |
---|
| 722 | w1 = G4ThreeVector( r1*cosPhi, r1*sinPhi, z1 ); |
---|
| 723 | transform.ApplyPointTransform( w0 ); |
---|
| 724 | transform.ApplyPointTransform( w1 ); |
---|
| 725 | |
---|
| 726 | G4ThreeVector deltaV = r0 > r1 ? w0-v0 : w1-v1; |
---|
| 727 | |
---|
| 728 | // |
---|
| 729 | // Build polygon, taking special care to keep the vertices |
---|
| 730 | // in order |
---|
| 731 | // |
---|
| 732 | polygon.ClearAllVertices(); |
---|
| 733 | |
---|
| 734 | polygon.AddVertexInOrder( v0 ); |
---|
| 735 | polygon.AddVertexInOrder( v1 ); |
---|
| 736 | polygon.AddVertexInOrder( w1 ); |
---|
| 737 | polygon.AddVertexInOrder( w0 ); |
---|
| 738 | |
---|
| 739 | // |
---|
| 740 | // Get extent |
---|
| 741 | // |
---|
| 742 | if (polygon.PartialClip( voxelLimit, axis )) |
---|
| 743 | { |
---|
| 744 | // |
---|
| 745 | // Get dot product of normal with target axis |
---|
| 746 | // |
---|
| 747 | polygon.SetNormal( deltaV.cross(v1-v0).unit() ); |
---|
| 748 | |
---|
| 749 | extentList.AddSurface( polygon ); |
---|
| 750 | } |
---|
| 751 | |
---|
| 752 | if (r2 >= 0) |
---|
| 753 | { |
---|
| 754 | // |
---|
| 755 | // Repeat, for transition piece |
---|
| 756 | // |
---|
| 757 | w2 = G4ThreeVector( r2*cosPhi, r2*sinPhi, z0 ); |
---|
| 758 | transform.ApplyPointTransform( w2 ); |
---|
| 759 | |
---|
| 760 | polygon.ClearAllVertices(); |
---|
| 761 | |
---|
| 762 | polygon.AddVertexInOrder( v2 ); |
---|
| 763 | polygon.AddVertexInOrder( v0 ); |
---|
| 764 | polygon.AddVertexInOrder( w0 ); |
---|
| 765 | polygon.AddVertexInOrder( w2 ); |
---|
| 766 | |
---|
| 767 | if (polygon.PartialClip( voxelLimit, axis )) |
---|
| 768 | { |
---|
| 769 | polygon.SetNormal( deltaV.cross(v0-v2).unit() ); |
---|
| 770 | |
---|
| 771 | extentList.AddSurface( polygon ); |
---|
| 772 | } |
---|
| 773 | |
---|
| 774 | v2 = w2; |
---|
| 775 | } |
---|
| 776 | |
---|
| 777 | // |
---|
| 778 | // Next vertex |
---|
| 779 | // |
---|
| 780 | v0 = w0; |
---|
| 781 | v1 = w1; |
---|
| 782 | } while( --numPhi > 0 ); |
---|
| 783 | |
---|
| 784 | // |
---|
| 785 | // We are almost done. But, it is important that we leave no |
---|
| 786 | // gaps in the surface of our solid. By using rFudge, however, |
---|
| 787 | // we've done exactly that, if we have a phi segment. |
---|
| 788 | // Add two additional faces if necessary |
---|
| 789 | // |
---|
| 790 | if (phiIsOpen && rNorm > DBL_MIN) |
---|
| 791 | { |
---|
| 792 | G4double cosPhi = std::cos(startPhi), |
---|
| 793 | sinPhi = std::sin(startPhi); |
---|
| 794 | |
---|
| 795 | G4ThreeVector a0( r[0]*cosPhi, r[0]*sinPhi, z[0] ), |
---|
| 796 | a1( r[1]*cosPhi, r[1]*sinPhi, z[1] ), |
---|
| 797 | b0( r0*cosPhi, r0*sinPhi, z[0] ), |
---|
| 798 | b1( r1*cosPhi, r1*sinPhi, z[1] ); |
---|
| 799 | |
---|
| 800 | transform.ApplyPointTransform( a0 ); |
---|
| 801 | transform.ApplyPointTransform( a1 ); |
---|
| 802 | transform.ApplyPointTransform( b0 ); |
---|
| 803 | transform.ApplyPointTransform( b1 ); |
---|
| 804 | |
---|
| 805 | polygon.ClearAllVertices(); |
---|
| 806 | |
---|
| 807 | polygon.AddVertexInOrder( a0 ); |
---|
| 808 | polygon.AddVertexInOrder( a1 ); |
---|
| 809 | polygon.AddVertexInOrder( b0 ); |
---|
| 810 | polygon.AddVertexInOrder( b1 ); |
---|
| 811 | |
---|
| 812 | if (polygon.PartialClip( voxelLimit , axis)) |
---|
| 813 | { |
---|
| 814 | G4ThreeVector normal( sinPhi, -cosPhi, 0 ); |
---|
| 815 | polygon.SetNormal( transform.TransformAxis( normal ) ); |
---|
| 816 | |
---|
| 817 | extentList.AddSurface( polygon ); |
---|
| 818 | } |
---|
| 819 | |
---|
| 820 | cosPhi = std::cos(startPhi+deltaPhi); |
---|
| 821 | sinPhi = std::sin(startPhi+deltaPhi); |
---|
| 822 | |
---|
| 823 | a0 = G4ThreeVector( r[0]*cosPhi, r[0]*sinPhi, z[0] ), |
---|
| 824 | a1 = G4ThreeVector( r[1]*cosPhi, r[1]*sinPhi, z[1] ), |
---|
| 825 | b0 = G4ThreeVector( r0*cosPhi, r0*sinPhi, z[0] ), |
---|
| 826 | b1 = G4ThreeVector( r1*cosPhi, r1*sinPhi, z[1] ); |
---|
| 827 | transform.ApplyPointTransform( a0 ); |
---|
| 828 | transform.ApplyPointTransform( a1 ); |
---|
| 829 | transform.ApplyPointTransform( b0 ); |
---|
| 830 | transform.ApplyPointTransform( b1 ); |
---|
| 831 | |
---|
| 832 | polygon.ClearAllVertices(); |
---|
| 833 | |
---|
| 834 | polygon.AddVertexInOrder( a0 ); |
---|
| 835 | polygon.AddVertexInOrder( a1 ); |
---|
| 836 | polygon.AddVertexInOrder( b0 ); |
---|
| 837 | polygon.AddVertexInOrder( b1 ); |
---|
| 838 | |
---|
| 839 | if (polygon.PartialClip( voxelLimit, axis )) |
---|
| 840 | { |
---|
| 841 | G4ThreeVector normal( -sinPhi, cosPhi, 0 ); |
---|
| 842 | polygon.SetNormal( transform.TransformAxis( normal ) ); |
---|
| 843 | |
---|
| 844 | extentList.AddSurface( polygon ); |
---|
| 845 | } |
---|
| 846 | } |
---|
| 847 | |
---|
| 848 | return; |
---|
| 849 | } |
---|
| 850 | |
---|
| 851 | |
---|
| 852 | // |
---|
| 853 | // DistanceAway |
---|
| 854 | // |
---|
| 855 | // Calculate distance of a point from our conical surface, including the effect |
---|
| 856 | // of any phi segmentation |
---|
| 857 | // |
---|
| 858 | // Arguments: |
---|
| 859 | // p - (in) Point to check |
---|
| 860 | // opposite - (in) If true, check opposite hemisphere (see below) |
---|
| 861 | // distOutside - (out) Additional distance outside the edges of the surface |
---|
| 862 | // edgeRZnorm - (out) if negative, point is inside |
---|
| 863 | // |
---|
| 864 | // return value = distance from the conical plane, if extrapolated beyond edges, |
---|
| 865 | // signed by whether the point is in inside or outside the shape |
---|
| 866 | // |
---|
| 867 | // Notes: |
---|
| 868 | // * There are two answers, depending on which hemisphere is considered. |
---|
| 869 | // |
---|
| 870 | G4double G4PolyconeSide::DistanceAway( const G4ThreeVector &p, |
---|
| 871 | G4bool opposite, |
---|
| 872 | G4double &distOutside2, |
---|
| 873 | G4double *edgeRZnorm ) |
---|
| 874 | { |
---|
| 875 | // |
---|
| 876 | // Convert our point to r and z |
---|
| 877 | // |
---|
| 878 | G4double rx = p.perp(), zx = p.z(); |
---|
| 879 | |
---|
| 880 | // |
---|
| 881 | // Change sign of r if opposite says we should |
---|
| 882 | // |
---|
| 883 | if (opposite) rx = -rx; |
---|
| 884 | |
---|
| 885 | // |
---|
| 886 | // Calculate return value |
---|
| 887 | // |
---|
| 888 | G4double deltaR = rx - r[0], deltaZ = zx - z[0]; |
---|
| 889 | G4double answer = deltaR*rNorm + deltaZ*zNorm; |
---|
| 890 | |
---|
| 891 | // |
---|
| 892 | // Are we off the surface in r,z space? |
---|
| 893 | // |
---|
| 894 | G4double s = deltaR*rS + deltaZ*zS; |
---|
| 895 | if (s < 0) |
---|
| 896 | { |
---|
| 897 | distOutside2 = s*s; |
---|
| 898 | if (edgeRZnorm) *edgeRZnorm = deltaR*rNormEdge[0] + deltaZ*zNormEdge[0]; |
---|
| 899 | } |
---|
| 900 | else if (s > length) |
---|
| 901 | { |
---|
| 902 | distOutside2 = sqr( s-length ); |
---|
| 903 | if (edgeRZnorm) |
---|
| 904 | { |
---|
| 905 | G4double deltaR = rx - r[1], deltaZ = zx - z[1]; |
---|
| 906 | *edgeRZnorm = deltaR*rNormEdge[1] + deltaZ*zNormEdge[1]; |
---|
| 907 | } |
---|
| 908 | } |
---|
| 909 | else |
---|
| 910 | { |
---|
| 911 | distOutside2 = 0; |
---|
| 912 | if (edgeRZnorm) *edgeRZnorm = answer; |
---|
| 913 | } |
---|
| 914 | |
---|
| 915 | if (phiIsOpen) |
---|
| 916 | { |
---|
| 917 | // |
---|
| 918 | // Finally, check phi |
---|
| 919 | // |
---|
| 920 | G4double phi = p.phi(); |
---|
| 921 | while( phi < startPhi ) phi += twopi; |
---|
| 922 | |
---|
| 923 | if (phi > startPhi+deltaPhi) |
---|
| 924 | { |
---|
| 925 | // |
---|
| 926 | // Oops. Are we closer to the start phi or end phi? |
---|
| 927 | // |
---|
| 928 | G4double d1 = phi-startPhi-deltaPhi; |
---|
| 929 | while( phi > startPhi ) phi -= twopi; |
---|
| 930 | G4double d2 = startPhi-phi; |
---|
| 931 | |
---|
| 932 | if (d2 < d1) d1 = d2; |
---|
| 933 | |
---|
| 934 | // |
---|
| 935 | // Add result to our distance |
---|
| 936 | // |
---|
| 937 | G4double dist = d1*rx; |
---|
| 938 | |
---|
| 939 | distOutside2 += dist*dist; |
---|
| 940 | if (edgeRZnorm) |
---|
| 941 | { |
---|
| 942 | *edgeRZnorm = std::max(std::fabs(*edgeRZnorm),std::fabs(dist)); |
---|
| 943 | } |
---|
| 944 | } |
---|
| 945 | } |
---|
| 946 | |
---|
| 947 | return answer; |
---|
| 948 | } |
---|
| 949 | |
---|
| 950 | |
---|
| 951 | // |
---|
| 952 | // PointOnCone |
---|
| 953 | // |
---|
| 954 | // Decide if a point is on a cone and return normal if it is |
---|
| 955 | // |
---|
| 956 | G4bool G4PolyconeSide::PointOnCone( const G4ThreeVector &hit, |
---|
| 957 | G4double normSign, |
---|
| 958 | const G4ThreeVector &p, |
---|
| 959 | const G4ThreeVector &v, |
---|
| 960 | G4ThreeVector &normal ) |
---|
| 961 | { |
---|
| 962 | G4double rx = hit.perp(); |
---|
| 963 | // |
---|
| 964 | // Check radial/z extent, as appropriate |
---|
| 965 | // |
---|
| 966 | if (!cone->HitOn( rx, hit.z() )) return false; |
---|
| 967 | |
---|
| 968 | if (phiIsOpen) |
---|
| 969 | { |
---|
| 970 | G4double phiTolerant = 2.0*kCarTolerance/(rx+kCarTolerance); |
---|
| 971 | // |
---|
| 972 | // Check phi segment. Here we have to be careful |
---|
| 973 | // to use the standard method consistent with |
---|
| 974 | // PolyPhiFace. See PolyPhiFace::InsideEdgesExact |
---|
| 975 | // |
---|
| 976 | G4double phi = hit.phi(); |
---|
| 977 | while( phi < startPhi-phiTolerant ) phi += twopi; |
---|
| 978 | |
---|
| 979 | if (phi > startPhi+deltaPhi+phiTolerant) return false; |
---|
| 980 | |
---|
| 981 | if (phi > startPhi+deltaPhi-phiTolerant) |
---|
| 982 | { |
---|
| 983 | // |
---|
| 984 | // Exact treatment |
---|
| 985 | // |
---|
| 986 | G4ThreeVector qx = p + v; |
---|
| 987 | G4ThreeVector qa = qx - corners[2], |
---|
| 988 | qb = qx - corners[3]; |
---|
| 989 | G4ThreeVector qacb = qa.cross(qb); |
---|
| 990 | |
---|
| 991 | if (normSign*qacb.dot(v) < 0) return false; |
---|
| 992 | } |
---|
| 993 | else if (phi < phiTolerant) |
---|
| 994 | { |
---|
| 995 | G4ThreeVector qx = p + v; |
---|
| 996 | G4ThreeVector qa = qx - corners[1], |
---|
| 997 | qb = qx - corners[0]; |
---|
| 998 | G4ThreeVector qacb = qa.cross(qb); |
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| 999 | |
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| 1000 | if (normSign*qacb.dot(v) < 0) return false; |
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| 1001 | } |
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| 1002 | } |
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| 1003 | |
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| 1004 | // |
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| 1005 | // We have a good hit! Calculate normal |
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| 1006 | // |
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| 1007 | if (rx < DBL_MIN) |
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| 1008 | normal = G4ThreeVector( 0, 0, zNorm < 0 ? -1 : 1 ); |
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| 1009 | else |
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| 1010 | normal = G4ThreeVector( rNorm*hit.x()/rx, rNorm*hit.y()/rx, zNorm ); |
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| 1011 | return true; |
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| 1012 | } |
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| 1013 | |
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| 1014 | |
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| 1015 | // |
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| 1016 | // FindLineIntersect |
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| 1017 | // |
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| 1018 | // Decide the point at which two 2-dimensional lines intersect |
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| 1019 | // |
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| 1020 | // Equation of line: x = x1 + s*tx1 |
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| 1021 | // y = y1 + s*ty1 |
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| 1022 | // |
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| 1023 | // It is assumed that the lines are *not* parallel |
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| 1024 | // |
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| 1025 | void G4PolyconeSide::FindLineIntersect( G4double x1, G4double y1, |
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| 1026 | G4double tx1, G4double ty1, |
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| 1027 | G4double x2, G4double y2, |
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| 1028 | G4double tx2, G4double ty2, |
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| 1029 | G4double &x, G4double &y ) |
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| 1030 | { |
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| 1031 | // |
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| 1032 | // The solution is a simple linear equation |
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| 1033 | // |
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| 1034 | G4double deter = tx1*ty2 - tx2*ty1; |
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| 1035 | |
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| 1036 | G4double s1 = ((x2-x1)*ty2 - tx2*(y2-y1))/deter; |
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| 1037 | G4double s2 = ((x2-x1)*ty1 - tx1*(y2-y1))/deter; |
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| 1038 | |
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| 1039 | // |
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| 1040 | // We want the answer to not depend on which order the |
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| 1041 | // lines were specified. Take average. |
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| 1042 | // |
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| 1043 | x = 0.5*( x1+s1*tx1 + x2+s2*tx2 ); |
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| 1044 | y = 0.5*( y1+s1*ty1 + y2+s2*ty2 ); |
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| 1045 | } |
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