SUBROUTINE CDCTRACKING(nchambers,nwires,nwires_tot,nhitmax,
     &      nhits,dv,t0,drift_dc,dx_dc,x_dc,x0,tant,xres,cdcfail)

      implicit none

      integer nchambers,ncells,nhitmax,nwires,nwires_tot,k1,k2,ind
      integer region,nhits(nchambers,nwires)
      real*4    sign1,sign2  
      real*4 dv(nchambers,nwires),t0(nchambers,nwires)
      real*4 drift_dc(nchambers,nwires,nhitmax)
      real*4 dx_dc(nchambers,nwires,nhitmax)
      real*4 x_dc(nchambers,nwires,nhitmax),xpos(nchambers,nwires)
      real*4 zpos(nchambers,nwires)
      real*4 xres,tant,x0      

      real*4 x_draw(nwires_tot),z_draw(nwires_tot),xwire(nwires_tot)
      real*4 xfit(6),zfit(6)

      logical cdcfail


CCCCCCCC      BEGIN DC TRACKING     CCCCCCCC


        do k1 = 1,nchambers           !!!  Loop over chambers           !!!
          do k2 = 1,2                 !!!  Loop over cells              !!!
                                      !!!  For now only consider        !!!
                                      !!!  hit #1 for each wire.        !!!

CCCCC  DETERMINE THE REGION IN DC FOR HIT - For breaking L/R ambiguity   CCCCC
CCCCC     of X-wires (The X-wires are the first 2 in each cell).         CCCCC
 
            call dcregion(drift_dc(k1,k2,1),drift_dc(k1,(k2+2),1),
     &                     region,sign1,sign2)
            if(k2.EQ.2) then   
              sign1 = -sign1    !!!  Left for 1st wire in cell  !!!
              sign2 = -sign2    !!!  Left for 2nd wire in cell  !!!
            endif
            dx_dc(k1,k2,1) = sign1*drift_dc(k1,k2,1)  !!!  Absolute dx = x-xwire  !!!
            dx_dc(k1,(k2+2),1) = sign2*drift_dc(k1,(k2+2),1)
            dx_dc(k1,(k2+3),1) = drift_dc(k1,(k2+3),1)/cos(0.11055)
          enddo
        enddo 

        call dc_parms(nchambers,nwires,xpos,dv,t0,zpos)  !!! Why do I need this here ?!!!
 
        ind = 0  
        do k1=1,nchambers     !!!  Calculate absolute X-position for hit on each wire  !!!
         do k2=1,nwires
           
           if(nhits(k1,k2).EQ.0) then
             x_dc(k1,k2,1) = 5000.
           else
             x_dc(k1,k2,1) = xpos(k1,k2) + dx_dc(k1,k2,1)
             if(k2.GT.4) then   !!!  Deal with slanted wires - this currently stinks! 
               if(abs(x_dc(k1,k2,1)-x_dc(k1,k2-2,1)).GT.(0.8*2.54)) then
                 x_dc(k1,k2,1) = xpos(k1,k2) - dx_dc(k1,k2,1)
               endif
             endif
           endif

           ind = ind + 1

           x_draw(ind) = x_dc(k1,k2,1)  !!! transform hits into drawing coordinates  !!!
           z_draw(ind) = zpos(k1,k2) 
           xwire(ind) = xpos(k1,k2)   !!!  X-position for each wire


         enddo
        enddo

        call linfitx(nchambers,nwires,nhitmax,nhits,x_dc,zpos,x0,
     &              tant,xres,cdcfail)  !!!  Call line fitting routine.  Currently uses    !!!
                                        !!!  only first 2 wires in each cell to determine  !!!
                                        !!!  X-position and angle.                         !!!   

CCCCC          END DC TRACKING            CCCCC

CCCCC         CALL HIGZ DRAWING ROUTINE        CCCCC

c        if(.not.cdcfail) 
c     &   call draw_dc(nwires_tot,xfit,zfit,x_draw,z_draw,xwire,x0,tant)

        return
        end