/* See frb_window.h */
/* Last edited on 2005-01-16 15:17:47 by stolfi */
/* Copyright © 2005 Universidade Estadual de Campinas. See note at end of file. */

#include <frb_window.h>
#include <frb_types.h>
#include <frb_proc.h>

#include <nget.h>
#include <fget.h>
#include <filefmt.h>

bool frb_window_is_empty ( frb_window_t *w )
  { return 
      (w->r[0].end[0] >= w->r[0].end[1]) ||
      (w->r[1].end[0] >= w->r[1].end[1]);
  }
  
frb_window_t frb_window_join ( frb_window_t *w1, frb_window_t *w2 )
  { frb_window_t wr;
    int ax;
    for (ax = 0; ax < 2; ax++)
      { wr.r[ax].end[0] = frb_dmin(w1->r[ax].end[0], w2->r[ax].end[0]);
        wr.r[ax].end[1] = frb_dmax(w1->r[ax].end[1], w2->r[ax].end[1]);
      }
    return wr;
  }

frb_window_t frb_window_expand ( frb_window_t *w, double rel )
  { frb_window_t wr;
    int ax;
    for (ax = 0; ax < 2; ax++)
      { double extra = rel*frb_dmax(1.0e-100, w->r[ax].end[1] - w->r[ax].end[0]);
        wr.r[ax].end[0] = w->r[ax].end[0] - extra;
        wr.r[ax].end[1] = w->r[ax].end[1] + extra;
      }
    return wr;
  }

#define WindowFileVersion "2004-04-30"

frb_window_t frb_window_read( FILE *rd )
  {
    frb_window_t w;
    filefmt_read_header(rd, "frb_window_t", WindowFileVersion);
    w.r[0].end[0] = nget_double(rd, "XMin"); fget_eol(rd); 
    w.r[0].end[1] = nget_double(rd, "XMax"); fget_eol(rd); 
    w.r[1].end[0] = nget_double(rd, "YMin"); fget_eol(rd); 
    w.r[1].end[1] = nget_double(rd, "YMax"); fget_eol(rd); 
    filefmt_read_footer(rd, "frb_window_t");
    return w;
  }

/* COPYRIGHT AND AUTHORSHIP NOTICE

  Copyright © 2005 Universidade Estadual de Campinas (UNICAMP).
  Created by Helena C. G. Leitão and Jorge Stolfi in 1995--2005.
  
  This source file can be freely distributed, used, and modified,
  provided that this copyright and authorship notice is preserved in
  all copies, and that any modified versions of this file are clearly
  marked as such.
  
  This software has NO WARRANTY of correctness or applicability for
  any purpose. Neither the authors nor their employers shall be held
  responsible for any losses or damages that may result from its use.

  END OF NOTICE */