text: /* $Id: geom.h,v 1.14 2009/06/03 01:10:52 ellson Exp $ $Revision: 1.14 $ */
  /* vim:set shiftwidth=4 ts=8: */
  
  /**********************************************************
  *      This software is part of the graphviz package      *
  *                http://www.graphviz.org/                 *
  *                                                         *
  *            Copyright (c) 1994-2004 AT&T Corp.           *
  *                and is licensed under the                *
  *            Common Public License, Version 1.0           *
  *                      by AT&T Corp.                      *
  *                                                         *
  *        Information and Software Systems Research        *
  *              AT&T Research, Florham Park NJ             *
  **********************************************************/
  
  /* geometric types and macros (e.g. points and boxes) with application to, but
   * no specific dependance on graphs */
  
  #ifndef GV_GEOM_H
  #define GV_GEOM_H
  
  #ifdef HAVE_CONFIG_H
  #include "arith.h"
  #endif
  
  #ifdef __cplusplus
  extern "C" {
  #endif
      
  typedef struct { int x, y; } point;
  
  typedef struct pointf_s { double x, y; } pointf;
  
  /* tell pathplan/pathgeom.h */
  #define HAVE_POINTF_S
  
  typedef struct { point LL, UR; } box;
  
  typedef struct { pointf LL, UR; } boxf;
  
  #ifdef HAVE_CONFIG_H
  
  /* true if point p is inside box b */
  #define INSIDE(p,b)	(BETWEEN((b).LL.x,(p).x,(b).UR.x) && BETWEEN((b).LL.y,(p).y,(b).UR.y))
  
  /* true if boxes b0 and b1 overlap */
  #define OVERLAP(b0,b1)	(((b0).UR.x >= (b1).LL.x) && ((b1).UR.x >= (b0).LL.x) && ((b0).UR.y >= (b1).LL.y) && ((b1).UR.y >= (b0).LL.y))
  
  /* true if box b0 completely contains b1*/
  #define CONTAINS(b0,b1)	(((b0).UR.x >= (b1).UR.x) && ((b0).UR.y >= (b1).UR.y) && ((b0).LL.x <= (b1).LL.x) && ((b0).LL.y <= (b1).LL.y))
  
  /* expand box b as needed to enclose point p */
  #define EXPANDBP(b, p)	((b).LL.x = MIN((b).LL.x, (p).x), (b).LL.y = MIN((b).LL.y, (p).y), (b).UR.x = MAX((b).UR.x, (p).x), (b).UR.y = MAX((b).UR.y, (p).y))
  
  /* expand box b0 as needed to enclose box b1 */
  #define EXPANDBB(b0, b1) ((b0).LL.x = MIN((b0).LL.x, (b1).LL.x), (b0).LL.y = MIN((b0).LL.y, (b1).LL.y), (b0).UR.x = MAX((b0).UR.x, (b1).UR.x), (b0).UR.y = MAX((b0).UR.y, (b1).UR.y))
  
  /* clip box b0 to fit box b1 */
  #define CLIPBB(b0, b1) ((b0).LL.x = MAX((b0).LL.x, (b1).LL.x), (b0).LL.y = MAX((b0).LL.y, (b1).LL.y), (b0).UR.x = MIN((b0).UR.x, (b1).UR.x), (b0).UR.y = MIN((b0).UR.y, (b1).UR.y))
  
  #define LEN2(a,b)		(SQR(a) + SQR(b))
  #define LEN(a,b)		(sqrt(LEN2((a),(b))))
  
  #define DIST2(p,q)		(LEN2(((p).x - (q).x),((p).y - (q).y)))
  #define DIST(p,q)		(sqrt(DIST2((p),(q))))
  
  #define POINTS_PER_INCH	72
  #define POINTS_PER_PC		((double)POINTS_PER_INCH / 6)
  #define POINTS_PER_CM		((double)POINTS_PER_INCH * 0.393700787)
  #define POINTS_PER_MM		((double)POINTS_PER_INCH * 0.0393700787)
  
  #define POINTS(a_inches)	(ROUND((a_inches)*POINTS_PER_INCH))
  #define PS2INCH(a_points)	((a_points)/(double)POINTS_PER_INCH)
  
  #define P2PF(p,pf)		((pf).x = (p).x,(pf).y = (p).y)
  #define PF2P(pf,p)		((p).x = ROUND((pf).x),(p).y = ROUND((pf).y))
  
  #define B2BF(b,bf)		(P2PF((b).LL,(bf).LL),P2PF((b).UR,(bf).UR))
  #define BF2B(bf,b)		(PF2P((bf).LL,(b).LL),PF2P((bf).UR,(b).UR))
  
  #define APPROXEQ(a,b,tol)	(ABS((a) - (b)) < (tol))
  #define APPROXEQPT(p,q,tol)	(DIST2((p),(q)) < SQR(tol))
  
  /* some common tolerance values */
  #define MILLIPOINT .001
  #define MICROPOINT .000001
  
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif
  