[5] | 1 | // -*- C++ -*- |
---|
| 2 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 3 | // File: geom_2d.h // |
---|
| 4 | // Description: header file for two-dimensional geometry tools // |
---|
| 5 | // This file is part of the SISCone project. // |
---|
| 6 | // For more details, see http://projects.hepforge.org/siscone // |
---|
| 7 | // // |
---|
| 8 | // Copyright (c) 2006 Gavin Salam and Gregory Soyez // |
---|
| 9 | // // |
---|
| 10 | // This program is free software; you can redistribute it and/or modify // |
---|
| 11 | // it under the terms of the GNU General Public License as published by // |
---|
| 12 | // the Free Software Foundation; either version 2 of the License, or // |
---|
| 13 | // (at your option) any later version. // |
---|
| 14 | // // |
---|
| 15 | // This program is distributed in the hope that it will be useful, // |
---|
| 16 | // but WITHOUT ANY WARRANTY; without even the implied warranty of // |
---|
| 17 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // |
---|
| 18 | // GNU General Public License for more details. // |
---|
| 19 | // // |
---|
| 20 | // You should have received a copy of the GNU General Public License // |
---|
| 21 | // along with this program; if not, write to the Free Software // |
---|
| 22 | // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA // |
---|
| 23 | // // |
---|
| 24 | // $Revision:: 859 $// |
---|
| 25 | // $Date:: 2012-11-28 02:49:23 +0100 (Wed, 28 Nov 2012) $// |
---|
| 26 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 27 | |
---|
| 28 | #ifndef __GEOM_2D_H__ |
---|
| 29 | #define __GEOM_2D_H__ |
---|
| 30 | |
---|
| 31 | #include <iostream> |
---|
| 32 | #include <math.h> |
---|
| 33 | #include "defines.h" |
---|
| 34 | |
---|
| 35 | #ifndef M_PI |
---|
| 36 | #define M_PI 3.141592653589793238462643383279502884197 |
---|
| 37 | #endif |
---|
| 38 | |
---|
| 39 | namespace siscone{ |
---|
| 40 | |
---|
| 41 | /// return a result that corresponds to phi, but in the |
---|
| 42 | /// range (-pi..pi]; the result is only correct if -3pi < phi <= 3pi |
---|
| 43 | inline double phi_in_range(double phi) { |
---|
| 44 | if (phi <= -M_PI) phi += twopi; |
---|
| 45 | else if (phi > M_PI) phi -= twopi; |
---|
| 46 | return phi; |
---|
| 47 | } |
---|
| 48 | |
---|
| 49 | /// return the difference between the two phi values, |
---|
| 50 | /// placed in the correct range (-pi..pi], , assuming that phi1,phi2 |
---|
| 51 | /// are already in the correct range. |
---|
| 52 | inline double dphi(double phi1, double phi2) { |
---|
| 53 | return phi_in_range(phi1-phi2); |
---|
| 54 | } |
---|
| 55 | |
---|
| 56 | |
---|
| 57 | /// return the absolute difference between the two phi values, |
---|
| 58 | /// placed in the correct range, assuming that phi1,phi2 are already |
---|
| 59 | /// in the correct range. |
---|
| 60 | inline double abs_dphi(double phi1, double phi2) { |
---|
| 61 | double delta = fabs(phi1-phi2); |
---|
| 62 | return delta > M_PI ? twopi-delta : delta; |
---|
| 63 | } |
---|
| 64 | |
---|
| 65 | /// return the square of the argument |
---|
| 66 | inline double pow2(double x) {return x*x;} |
---|
| 67 | |
---|
| 68 | |
---|
| 69 | /** |
---|
| 70 | * \class Ctwovect |
---|
| 71 | * \brief class for holding a two-vector |
---|
| 72 | */ |
---|
| 73 | class Ctwovect { |
---|
| 74 | public: |
---|
| 75 | /// default ctor |
---|
| 76 | Ctwovect() : x(0.0), y(0.0) {} |
---|
| 77 | |
---|
| 78 | /// ctor with initialisation |
---|
| 79 | /// \param _x first coordinate |
---|
| 80 | /// \param _y second coordinate |
---|
| 81 | Ctwovect(double _x, double _y) : x(_x), y(_y) {} |
---|
| 82 | |
---|
| 83 | /// vector coordinates |
---|
| 84 | double x, y; |
---|
| 85 | |
---|
| 86 | /// norm (modulud square) of the vector |
---|
| 87 | inline double mod2() const {return pow2(x)+pow2(y);} |
---|
| 88 | |
---|
| 89 | /// modulus of the vector |
---|
| 90 | inline double modulus() const {return sqrt(mod2());} |
---|
| 91 | }; |
---|
| 92 | |
---|
| 93 | |
---|
| 94 | /// dot product of two 2-vectors |
---|
| 95 | /// \param a first 2-vect |
---|
| 96 | /// \param b second 2-vect |
---|
| 97 | /// \return a.b is returned |
---|
| 98 | inline double dot_product(const Ctwovect & a, const Ctwovect & b) { |
---|
| 99 | return a.x*b.x + a.y*b.y; |
---|
| 100 | } |
---|
| 101 | |
---|
| 102 | |
---|
| 103 | /// cross product of two 2-vectors |
---|
| 104 | /// \param a first 2-vect |
---|
| 105 | /// \param b second 2-vect |
---|
| 106 | /// \return a x b is returned |
---|
| 107 | inline double cross_product(const Ctwovect & a, const Ctwovect & b) { |
---|
| 108 | return a.x*b.y - a.y*b.x; |
---|
| 109 | } |
---|
| 110 | |
---|
| 111 | |
---|
| 112 | /** |
---|
| 113 | * \class Ceta_phi_range |
---|
| 114 | * \brief class for holding a covering range in eta-phi |
---|
| 115 | * |
---|
| 116 | * This class deals with ranges in the eta-phi plane. It |
---|
| 117 | * implements methods to test if two ranges overlap and |
---|
| 118 | * to take the union of two overlapping intervals. |
---|
| 119 | */ |
---|
| 120 | class Ceta_phi_range{ |
---|
| 121 | public: |
---|
| 122 | /// default ctor |
---|
| 123 | Ceta_phi_range(); |
---|
| 124 | |
---|
| 125 | /// ctor with initialisation |
---|
| 126 | /// we initialise with a centre (in eta,phi) and a radius |
---|
| 127 | /// \param c_eta eta coordinate of the centre |
---|
| 128 | /// \param c_phi phi coordinate of the centre |
---|
| 129 | /// \param R radius |
---|
| 130 | Ceta_phi_range(double c_eta, double c_phi, double R); |
---|
| 131 | |
---|
| 132 | /// assignment of range |
---|
| 133 | /// \param r range to assign to current one |
---|
| 134 | Ceta_phi_range& operator = (const Ceta_phi_range &r); |
---|
| 135 | |
---|
| 136 | /// add a particle to the range |
---|
| 137 | /// \param eta eta coordinate of the particle |
---|
| 138 | /// \param phi phi coordinate of the particle |
---|
| 139 | /// \return 0 on success, 1 on error |
---|
| 140 | int add_particle(const double eta, const double phi); |
---|
| 141 | |
---|
| 142 | /// eta range as a binary coding of covered cells |
---|
| 143 | unsigned int eta_range; |
---|
| 144 | |
---|
| 145 | /// phi range as a binary coding of covered cells |
---|
| 146 | unsigned int phi_range; |
---|
| 147 | |
---|
| 148 | // extremal value for eta |
---|
| 149 | static double eta_min; ///< minimal value for eta |
---|
| 150 | static double eta_max; ///< maximal value for eta |
---|
| 151 | |
---|
| 152 | private: |
---|
| 153 | /// return the cell index corrsponding to an eta value |
---|
| 154 | inline unsigned int get_eta_cell(double eta){ |
---|
| 155 | return (unsigned int) (1 << ((int) (32*((eta-eta_min)/(eta_max-eta_min))))); |
---|
| 156 | } |
---|
| 157 | |
---|
| 158 | /// return the cell index corrsponding to a phi value |
---|
| 159 | inline unsigned int get_phi_cell(double phi){ |
---|
| 160 | return (unsigned int) (1 << ((int) (32*phi/twopi+16)%32)); |
---|
| 161 | } |
---|
| 162 | }; |
---|
| 163 | |
---|
| 164 | /// test overlap |
---|
| 165 | /// \param r1 first range |
---|
| 166 | /// \param r2 second range |
---|
| 167 | /// \return true if overlap, false otherwise. |
---|
| 168 | bool is_range_overlap(const Ceta_phi_range &r1, const Ceta_phi_range &r2); |
---|
| 169 | |
---|
| 170 | /// compute union |
---|
| 171 | /// Note: we assume that the two intervals overlap |
---|
| 172 | /// \param r1 first range |
---|
| 173 | /// \param r2 second range |
---|
| 174 | /// \return union of the two ranges |
---|
| 175 | const Ceta_phi_range range_union(const Ceta_phi_range &r1, const Ceta_phi_range &r2); |
---|
| 176 | |
---|
| 177 | } |
---|
| 178 | |
---|
| 179 | #endif |
---|