GEANT321/gdraw/gdzoom.F

   1 *
   2 * $Id$
   3 *
   4 * $Log$
   5 * Revision 1.1.1.1  1995/10/24 10:20:29  cernlib
   6 * Geant
   7 *
   8 *
   9 #include "geant321/pilot.h"
  10 *CMZ :  3.21/02 29/03/94  15.41.27  by  S.Giani
  11 *-- Author :
  12       SUBROUTINE GDZOOM(ZOOMFU,ZOOMFV,UUZ0,VVZ0,UU0,VV0)
  13 C.
  14 C.    ******************************************************************
  15 C.    *                                                                *
  16 C.    *       Zoom by the factors ZOOMFU,ZOOMFV                        *
  17 C.    *       around screen coordinates UUZ0,VVZ0                      *
  18 C.    *       and places the resulting picture at UU0,VV0              *
  19 C.    *                                                                *
  20 C.    *       After GDZOOM has been called, any drawing operation      *
  21 C.    *       will actually draw accordingly to last GDZOOM parameters *
  22 C.    *                                                                *
  23 C.    *       If ZOOMFU or ZOOMFV is 0 (or negative) the zoom          *
  24 C.    *       parameters (GZUA,...,GZVC in common GCDRAW) are reset    *
  25 C.    *                                                                *
  26 C.    *    ==>Called by : <USER>, <GXINT>                              *
  27 C.    *       Author : P.Zanarini   *********                          *
  28 C.    *                                                                *
  29 C.    ******************************************************************
  30 C.
  31 #include "geant321/gcdraw.inc"
  32 C.
  33 C.    ------------------------------------------------------------------
  34 C.
  35       IF (ZOOMFU.LE.0.OR.ZOOMFV.LE.0) THEN
  36          GZUA=1
  37          GZVA=1
  38          GZUB=0
  39          GZVB=0
  40          GZUC=0
  41          GZVC=0
  42       ELSE
  43          GZUA=GZUA*ZOOMFU
  44          GZVA=GZVA*ZOOMFV
  45          GZUB=(GZUB+GZUC)*ZOOMFU
  46          GZVB=(GZVB+GZVC)*ZOOMFV
  47          GZUC=UU0-UUZ0*ZOOMFU
  48          GZVC=VV0-VVZ0*ZOOMFV
  49       ENDIF
  50 C
  51       END