GEANT321/ghits/gpdrif.F

   1 *
   2 * $Id$
   3 *
   4 * $Log$
   5 * Revision 1.1.1.1  1995/10/24 10:21:10  cernlib
   6 * Geant
   7 *
   8 *
   9 #include "geant321/pilot.h"
  10 *CMZ :  3.21/02 29/03/94  15.41.20  by  S.Giani
  11 *-- Author :
  12       SUBROUTINE GPDRIF (DETREP,HITREP,IOUT)
  13 C.
  14 C.    ******************************************************************
  15 C.    *                                                                *
  16 C     *     DETREP(1)=NUMBER OF WIRES                                  *
  17 C     *           (2)=WIRE SPACING                                     *
  18 C     *           (3)=SIN (ALPHA) (ALPHA=ANGLE OF THE NORMAL           *
  19 C     *                            TO THE WIRE WITH RESPECT TO         *
  20 C     *                            AXIS I)                             *
  21 C     *           (4)=COS (ALPHA)                                      *
  22 C     *           (5)=DISTANCE OF WIRE 1 FROM THE ORIGIN               *
  23 C     *           (6)=DRIFT VELOCITY (CM/NSEC)                         *
  24 C     *                                                                *
  25 C     *     HITREP(1)=X COORDINATE OF INTERSECTION                     *
  26 C     *           (2)=Y COORDINATE                                     *
  27 C     *                                                                *
  28 C     *     IOUT(1)=WIRE NUMBER                                        *
  29 C     *         (2)=DRIFT TIME (SIGNED TO AVOID RIGHT/LEFT AMBIGUITY)  *
  30 C.    *                                                                *
  31 C.    *    ==>Called by : <USER>, GUDIGI                               *
  32 C.    *       Authors    F.Carena, M.Hansroul  *********               *
  33 C.    *                                                                *
  34 C.    ******************************************************************
  35 C.
  36       DIMENSION HITREP(2), DETREP(6), IOUT(2)
  37 C.
  38 C.    ------------------------------------------------------------------
  39 C.
  40       IOUT(1) = - 1
  41       SP     = DETREP(2)
  42       DV     = DETREP(6)
  43       IF (SP.EQ.0.)                                   GO TO 99
  44       IF (DV.EQ.0.)                                   GO TO 99
  45 C
  46       X      = HITREP(1)
  47       Y      = HITREP(2)
  48       SA     = DETREP(3)
  49       CA     = DETREP(4)
  50       U      = X * CA + Y * SA
  51       OR     = DETREP(5)
  52       W      = (U - OR) / SP + 1.5
  53 C
  54       IW     = W
  55       NWIR   = DETREP(1)
  56       IF (IW.GT.NWIR)                                 GO TO 99
  57       IF (IW.LE.0)                                    GO TO 99
  58 C
  59       DIST   = U - OR - (IW - 1) * SP
  60       TDRIF  = DIST / DV
  61 C
  62       IOUT(1) = IW
  63       IOUT(2) = TDRIF
  64 C
  65   99  RETURN
  66       END