Category : Printer + Display Graphics
Archive   : PLYDAT.ZIP
Filename : DEF.H

/*
* def.h contains some useful definitions for "C" programs.
*
* Version: 2.2 (11/17/87)
* Author: Eric Haines, 3D/Eye, Inc.
*/

#define EPSILON 5.0e-6

#ifndef FALSE
#define FALSE 0
#endif

#ifndef NULL
#define NULL 0
#endif

#ifndef TRUE
#define TRUE 1
#endif

#ifndef PI
#define PI 3.141592653589793
#endif


typedef double MATRIX[4][4] ; /* row major form */

typedef struct {
double x ;
double y ;
double z ;
double w ;
} COORD4, *COORD4_P ;


#define ABSOLUTE(A) ( (A) < 0 ? -(A) : (A) )
#define FRACTION(A) ( (A) - (long)(A) )
#define MAX(A,B) ( (A) > (B) ? (A) : (B) )
#define MAX3(A,B,C) ( MAX( MAX( A,B ), C ) )
#define MIN(A,B) ( (A) < (B) ? (A) : (B) )
#define MIN3(A,B,C) ( MIN( MIN( A,B ), C ) )
#define SQR(A) ( (A) * (A) )

#define ADD2_COORD(r,a) { (r).x += (a).x; (r).y += (a).y;\
(r).z += (a).z; }
#define ADD3_COORD(r,a,b) { (r).x = (a).x + (b).x;\
(r).y = (a).y + (b).y;\
(r).z = (a).z + (b).z; }
#define COPY_COORD(r,a) { (r).x = (a).x; (r).y = (a).y; (r).z = (a).z;}
#define COPY_COORD4(r,a) { (r).x = (a).x; (r).y = (a).y; (r).z = (a).z;\
(r).w = (a).w; }
#define CROSS(r,a,b) { (r).x = (a).y * (b).z - (a).z * (b).y;\
(r).y = (a).z * (b).x - (a).x * (b).z;\
(r).z = (a).x * (b).y - (a).y * (b).x; }
#define DOT_PRODUCT(a,b) ( (a).x * (b).x +\
(a).y * (b).y +\
(a).z * (b).z )
#define SET_COORD(r,a,b,c) { (r).x = (a); (r).y = (b); (r).z = (c); }
#define SET_COORD4(r,a,b,c,d) { (r).x = (a); (r).y = (b); (r).z = (c);\
(r).w = (d); }
#define SUB2_COORD(r,a) { (r).x -= (a).x; (r).y -= (a).y;\
(r).z -= (a).z; }
#define SUB3_COORD(r,a,b) { (r).x = (a).x - (b).x;\
(r).y = (a).y - (b).y;\
(r).z = (a).z - (b).z; }