*
*=== Spotcm ===========================================================*
*
*
*----------------------------------------------------------------------*
*                                                                      *
*     Copyright (C) 2003-2019:  CERN & INFN                            *
*     All Rights Reserved.                                             *
*                                                                      *
*     Created on   27 April 2016   by         Alfredo Ferrari          *
*                                                CERN - EN             *
*                                                                      *
*          Pmspot(i) = Energy/n (if < 0) or total momentum of the i_th *
*                      spot                                            *
*          Dpspot(i) = momentum spread of the i_th spot                *
*          Wespot(i) = weight (eg n. of particles) of the i_th spot, it*
*                      is transformed into a cumulative array at the   *
*                      first Mlspot call                               *
*          Dasptx(i) = (x) angular divergence of the i_th spot         *
*          Daspty(i) = (y) angular divergence of the i_th spot         *
*          Sxspot(i) = sigma_x (FWHM) of the i_th spot                 *
*          Syspot(i) = sigma_y (FWHM) of the i_th spot                 *
*        Xyzspt(j,i) = starting position for the i_th spot             *
*        Uvwspt(j,i) = beam nominal direction (beam z-axis) for the    *
*                      i_th spot                                       *
*        Xaxspt(j,i) = beam x-axis for the i_th spot                   *
*        Yazspt(j,i) = beam y-axis for the i_th spot                   *
*          Amspot(i) = mass of the i_th spot beam particle             *
*          Ijspot(i) = id (Paprop numbering) of the i_th spot beam     *
*                      particle, or m, A and Z of the i_th spot beam   *
*                      particle, coded as usual                        *
*          Lfspot(i) = logical flags for the i_th spot coded as:       *
*                      Ldxgss = mod(lfspot(i),10) > 0                  *
*                      Ldygss = mod(lfspot(i),100)/10 > 0              *
*                      Lbeamc = mod(lfspot(i),1000)/100 > 0            *
*                      Lbaxis = mod(lfspot(i),10000)/1000 > 0          *
*          Dbkspt(i) = (backward) distance for backtracing the spot    *
*                      starting point                                  *
*        Krtspt(j,i) = transformation matrix Krtspt(1,i) must be copied*
*                      into transformation matrix Krtspt(2,i) when the *
*                      i_th spot is processed                          *
*          Irtspt(i) = flag whether to apply Krtspt(1/2,j) to the i_th *
*                      beam spot position and direction (0 = do not    *
*                      apply, +1 = apply the transformation, -1 = apply*
*                      the inverse transformation                      *
*          Lbkspt(i) = logical flag for backtracing the spot starting  *
*                      point                                           *
*             Nmspot = total number of spots                           *
*             Nsptcr = number of the current spot                      *
*                                                                      *
*----------------------------------------------------------------------*
*
      PARAMETER ( MXSPOT = 50000 )
      LOGICAL LBKSPT, LPRSPT
*
      COMMON / SPOTCM / PMSPOT   (MXSPOT), DPSPOT   (MXSPOT),
     &                  WESPOT (0:MXSPOT), AMSPOT   (MXSPOT),
     &                  DASPTX   (MXSPOT), DASPTY   (MXSPOT),
     &                  SXSPOT   (MXSPOT), SYSPOT   (MXSPOT),
     &                  XYZSPT (3,MXSPOT), UVWSPT (3,MXSPOT),
     &                  XAXSPT (3,MXSPOT), YAXSPT (3,MXSPOT),
     &                  DBKSPT   (MXSPOT), IJSPOT   (MXSPOT),
     &                  KRTSPT (2,MXSPOT), IRTSPT   (MXSPOT),
     &                  LFSPOT   (MXSPOT), LBKSPT   (MXSPOT),
     &                  NMSPOT, LPRSPT, NSPTCR
      SAVE / SPOTCM /