cv/mgflib/parser.h

/* Copyright (c) 1994 Regents of the University of California */

/* SCCSid "$SunId$ LBL" */

/*
 * Header file for MGF interpreter
 */

/* must include stdio.h before us */

                        /* Entities (order doesn't really matter) */
#define MG_E_COMMENT    0
#define MG_E_COLOR      1
#define MG_E_CONE       2
#define MG_E_CXY        3
#define MG_E_CYL        4
#define MG_E_ED         5
#define MG_E_FACE       6
#define MG_E_INCLUDE    7
#define MG_E_IES        8
#define MG_E_MATERIAL   9
#define MG_E_NORMAL     10
#define MG_E_OBJECT     11
#define MG_E_POINT      12
#define MG_E_RD         13
#define MG_E_RING       14
#define MG_E_RS         15
#define MG_E_SPH        16
#define MG_E_TD         17
#define MG_E_TORUS      18
#define MG_E_TS         19
#define MG_E_VERTEX     20
#define MG_E_XF         21

#define MG_NENTITIES    22

#define MG_NAMELIST     {"#","c","cone","cxy","cyl","ed","f","i","ies",\
        "m","n","o","p","rd","ring","rs","sph","td","torus","ts","v","xf"}

#define MG_MAXELEN      6

extern char     mg_ename[MG_NENTITIES][MG_MAXELEN];

                        /* Handler routines for each entity */

#ifdef NOPROTO
extern int      (*mg_ehand[MG_NENTITIES])();
#else
extern int      (*mg_ehand[MG_NENTITIES])(int argc, char **argv);
#endif

                        /* Error codes */
#define MG_OK           0               /* normal return value */
#define MG_EUNK         1               /* unknown entity */
#define MG_EARGC        2               /* wrong number of arguments */
#define MG_ETYPE        3               /* argument type error */
#define MG_EILL         4               /* illegal argument value */
#define MG_EUNDEF       5               /* undefined reference */
#define MG_ENOFILE      6               /* cannot open input file */
#define MG_EINCL        7               /* error in included file */
#define MG_EMEM         8               /* out of memory */
#define MG_ESEEK        9               /* file seek error */
#define MG_EBADMAT      10              /* bad material specification */

#define MG_NERRS        11

extern char     *mg_err[MG_NERRS];

/*
 * The general process for running the parser is to fill in the mg_ehand
 * array with handlers for each entity you know how to handle.
 * Then, call mg_init to fill in the rest.  This function will report
 * an error and quit if you try to support an inconsistent set of entities.
 * For each file you want to parse, call mg_load with the file name.
 * To read from standard input, use NULL as the file name.
 * For additional control over error reporting and file management,
 * use mg_open, mg_read, mg_parse and mg_close instead of mg_load.
 * To free any data structures and clear the parser, use mg_clear.
 * If there is an error, mg_load, mg_open, mg_parse, and mg_rewind
 * will return an error from the list above.  In addition, mg_load
 * will report the error to stderr.  The mg_read routine returns 0
 * when the end of file has been reached.
 */

#define MG_MAXLINE      512             /* maximum input line length */
#define MG_MAXARGC      (MG_MAXLINE/4)  /* maximum argument count */

typedef struct mg_fctxt {
        char    *fname;                         /* file name */
        FILE    *fp;                            /* stream pointer */
        char    inpline[MG_MAXLINE];            /* input line */
        int     lineno;                         /* line number */
        struct mg_fctxt *prev;                  /* previous context */
} MG_FCTXT;

extern MG_FCTXT *mg_file;               /* current file context */

#ifdef NOPROTO
extern void     mg_init();              /* fill in mg_ehand array */
extern int      mg_load();              /* parse a file */
extern int      mg_open();              /* open new input file */
extern int      mg_read();              /* read next line */
extern int      mg_parse();             /* parse current line */
extern int      mg_rewind();            /* rewind input file */
extern void     mg_close();             /* close input file */
extern void     mg_clear();             /* clear parser */
extern int      mg_iterate();
#else
extern void     mg_init(void);          /* fill in mg_ehand array */
extern int      mg_load(char *);        /* parse a file */
extern int      mg_open(MG_FCTXT *, char *);    /* open new input file */
extern int      mg_read(void);          /* read next line */
extern int      mg_parse(void);         /* parse current line */
extern int      mg_rewind(void);        /* rewind input file */
extern void     mg_close(void);         /* close input file */
extern void     mg_clear(void);         /* clear parser */
extern int      mg_iterate(int, char **, int (*)(void));
#endif

#ifndef MG_NQCD
#define MG_NQCD         5               /* default number of divisions */
#endif

extern int      mg_nqcdivs;             /* divisions per quarter circle */

/*
 * The following library routines are included for your convenience:
 */

#ifdef NOPROTO
extern int mg_entity();                 /* get entity number from its name */
extern int isint();                     /* non-zero if integer format */
extern int isflt();                     /* non-zero if floating point format */
#else
extern int mg_entity(char *);           /* get entity number from its name */
extern int isint(char *);               /* non-zero if integer format */
extern int isflt(char *);               /* non-zero if floating point format */
#endif

/************************************************************************
 *      Definitions for 3-d vector manipulation functions
 */

#ifdef  SMLFLT
#define  FLOAT          float
#define  FTINY          (1e-3)
#else
#define  FLOAT          double
#define  FTINY          (1e-6)
#endif
#define  FHUGE          (1e10)

typedef FLOAT  FVECT[3];

#define  VCOPY(v1,v2)   ((v1)[0]=(v2)[0],(v1)[1]=(v2)[1],(v1)[2]=(v2)[2])
#define  DOT(v1,v2)     ((v1)[0]*(v2)[0]+(v1)[1]*(v2)[1]+(v1)[2]*(v2)[2])
#define  VSUM(vr,v1,v2,f)       ((vr)[0]=(v1)[0]+(f)*(v2)[0], \
                                (vr)[1]=(v1)[1]+(f)*(v2)[1], \
                                (vr)[2]=(v1)[2]+(f)*(v2)[2])

#define is0vect(v)      (DOT(v,v) < FTINY*FTINY)

#define round0(x)       if (x <= FTINY && x >= -FTINY) x = 0

#ifdef NOPROTO
extern double   normalize();            /* normalize a vector */
#else
extern double   normalize(FVECT);       /* normalize a vector */
#endif

/************************************************************************
 *      Definitions for context handling routines
 *      (materials, colors, vectors)
 */

typedef struct {
        float   cx, cy;         /* XY chromaticity coordinates */
} C_COLOR;              /* color context */

typedef struct {
        char    *name;          /* material name */
        int     clock;          /* incremented each change -- resettable */
        float   rd;             /* diffuse reflectance */
        C_COLOR rd_c;           /* diffuse reflectance color */
        float   td;             /* diffuse transmittance */
        C_COLOR td_c;           /* diffuse transmittance color */
        float   ed;             /* diffuse emittance */
        C_COLOR ed_c;           /* diffuse emittance color */
        float   rs;             /* specular reflectance */
        C_COLOR rs_c;           /* specular reflectance color */
        float   rs_a;           /* specular reflectance roughness */
        float   ts;             /* specular transmittance */
        C_COLOR ts_c;           /* specular transmittance color */
        float   ts_a;           /* specular transmittance roughness */
} C_MATERIAL;           /* material context */

typedef struct {
        FVECT   p, n;           /* point and normal */
} C_VERTEX;             /* vertex context */

#define isgrey(cxy)     ((cxy)->cx > .31 && (cxy)->cx < .35 && \
                        (cxy)->cy > .31 && (cxy)->cy < .35)

#define C_DEFCOLOR      {.333,.333}
#define C_DEFMATERIAL   {NULL,1,0.,C_DEFCOLOR,0.,C_DEFCOLOR,0.,C_DEFCOLOR,\
                                        0.,C_DEFCOLOR,0.,0.,C_DEFCOLOR,0.}
#define C_DEFVERTEX     {{0.,0.,0.},{0.,0.,0.}}

extern C_COLOR          *c_ccolor;      /* the current color */
extern C_MATERIAL       *c_cmaterial;   /* the current material */
extern C_VERTEX         *c_cvertex;     /* the current vertex */

#ifdef NOPROTO
extern int      c_hcolor();                     /* handle color entity */
extern int      c_hmaterial();                  /* handle material entity */
extern int      c_hvertex();                    /* handle vertex entity */
extern void     c_clearall();                   /* clear context tables */
extern C_VERTEX *c_getvert();                   /* get a named vertex */
#else
extern int      c_hcolor(int, char **);         /* handle color entity */
extern int      c_hmaterial(int, char **);      /* handle material entity */
extern int      c_hvertex(int, char **);        /* handle vertex entity */
extern void     c_clearall(void);               /* clear context tables */
extern C_VERTEX *c_getvert(char *);             /* get a named vertex */
#endif

/*************************************************************************
 *      Definitions for hierarchical object name handler
 */

extern int      obj_nnames;             /* depth of name hierarchy */
extern char     **obj_name;             /* names in hierarchy */

#ifdef NOPROTO
extern int      obj_handler();                  /* handle an object entity */
extern void     obj_clear();                    /* clear object stack */
#else
extern int      obj_handler(int, char **);      /* handle an object entity */
extern void     obj_clear(void);                /* clear object stack */
#endif

/**************************************************************************
 *      Definitions for hierarchical transformation handler
 */

typedef FLOAT  MAT4[4][4];

#ifdef  BSD
#define  copymat4(m4a,m4b)      bcopy((char *)m4b,(char *)m4a,sizeof(MAT4))
#else
#define  copymat4(m4a,m4b)      (void)memcpy((char *)m4a,(char *)m4b,sizeof(MAT4))
extern char  *memcpy();
#endif

#define  MAT4IDENT              { {1.,0.,0.,0.}, {0.,1.,0.,0.}, \
                                {0.,0.,1.,0.}, {0.,0.,0.,1.} }

extern MAT4  m4ident;

#define  setident4(m4)          copymat4(m4, m4ident)

                                /* regular transformation */
typedef struct {
        MAT4  xfm;                              /* transform matrix */
        FLOAT  sca;                             /* scalefactor */
}  XF;

#define identxf(xp)             (void)(setident4((xp)->xfm),(xp)->sca=1.0)

typedef struct xf_spec {
        short   xac;            /* transform argument count */
        short   xav0;           /* zeroeth argument in xf_argv array */
        XF      xf;             /* cumulative transformation */
        struct xf_spec  *prev;  /* previous transformation context */
} XF_SPEC;

extern int      xf_argc;                        /* total # transform args. */
extern char     **xf_argv;                      /* transform arguments */
extern XF_SPEC  *xf_context;                    /* current context */

/*
 * The transformation handler should do most of the work that needs
 * doing.  Just pass it any xf entities, then use the associated
 * functions to transform and translate points, transform vectors
 * (without translation), rotate vectors (without scaling) and scale
 * values appropriately.
 *
 * The routines xf_xfmpoint, xf_xfmvect and xf_rotvect take two
 * 3-D vectors (which may be identical), transforms the second and
 * puts the result into the first.
 */

#ifdef NOPROTO

extern int      xf_handler();           /* handle xf entity */
extern void     xf_xfmpoint();          /* transform point */
extern void     xf_xfmvect();           /* transform vector */
extern void     xf_rotvect();           /* rotate vector */
extern double   xf_scale();             /* scale a value */
extern void     xf_clear();             /* clear xf stack */

/* The following are support routines you probably won't call directly */

extern void     multmat4();             /* m4a = m4b X m4c */
extern void     multv3();               /* v3a = v3b X m4 (vectors) */
extern void     multp3();               /* p3a = p3b X m4 (points) */
extern int      xf();                   /* interpret transform spec. */

#else

extern int      xf_handler(int, char **);       /* handle xf entity */
extern void     xf_xfmpoint(FVECT, FVECT);      /* transform point */
extern void     xf_xfmvect(FVECT, FVECT);       /* transform vector */
extern void     xf_rotvect(FVECT, FVECT);       /* rotate vector */
extern double   xf_scale(double);               /* scale a value */
extern void     xf_clear(void);                 /* clear xf stack */

/* The following are support routines you probably won't call directly */

extern void     multmat4(MAT4, MAT4, MAT4);     /* m4a = m4b X m4c */
extern void     multv3(FVECT, FVECT, MAT4);     /* v3a = v3b X m4 (vectors) */
extern void     multp3(FVECT, FVECT, MAT4);     /* p3a = p3b X m4 (points) */
extern int      xf(XF, int, char **);           /* interpret transform spec. */

#endif

/************************************************************************
 *      Miscellaneous definitions
 */

#ifdef  M_PI
#define  PI             M_PI
#else
#define  PI             3.14159265358979323846
#endif

#ifdef DCL_ATOF
extern double   atof();
#endif

#ifndef MEM_PTR
#define MEM_PTR         void *
#endif

extern MEM_PTR  malloc();
extern MEM_PTR  calloc();
extern MEM_PTR  realloc();
extern void     free();
Revision:	1.4
Committed:	Thu Jun 23 07:48:36 1994 UTC (29 years, 10 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+1 -0 lines
Log Message:	improved table lookup routines with new delete function
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1994 Regents of the University of California */
2
3			/* SCCSid "$SunId$ LBL" */
4
5			/*
6			* Header file for MGF interpreter
7			*/
8
9			/* must include stdio.h before us */
10
11			/* Entities (order doesn't really matter) */
12			#define MG_E_COMMENT 0
13			#define MG_E_COLOR 1
14			#define MG_E_CONE 2
15			#define MG_E_CXY 3
16			#define MG_E_CYL 4
17			#define MG_E_ED 5
18			#define MG_E_FACE 6
19			#define MG_E_INCLUDE 7
20			#define MG_E_IES 8
21			#define MG_E_MATERIAL 9
22			#define MG_E_NORMAL 10
23			#define MG_E_OBJECT 11
24			#define MG_E_POINT 12
25			#define MG_E_RD 13
26			#define MG_E_RING 14
27			#define MG_E_RS 15
28			#define MG_E_SPH 16
29			#define MG_E_TD 17
30			#define MG_E_TORUS 18
31			#define MG_E_TS 19
32			#define MG_E_VERTEX 20
33			#define MG_E_XF 21
34
35			#define MG_NENTITIES 22
36
37			#define MG_NAMELIST {"#","c","cone","cxy","cyl","ed","f","i","ies",\
38			"m","n","o","p","rd","ring","rs","sph","td","torus","ts","v","xf"}
39
40			#define MG_MAXELEN 6
41
42			extern char mg_ename[MG_NENTITIES][MG_MAXELEN];
43
44			/* Handler routines for each entity */
45
46			#ifdef NOPROTO
47			extern int (*mg_ehand[MG_NENTITIES])();
48			#else
49			extern int (mg_ehand[MG_NENTITIES])(int argc, char *argv);
50			#endif
51
52			/* Error codes */
53			#define MG_OK 0 /* normal return value */
54			#define MG_EUNK 1 /* unknown entity */
55			#define MG_EARGC 2 /* wrong number of arguments */
56			#define MG_ETYPE 3 /* argument type error */
57			#define MG_EILL 4 /* illegal argument value */
58			#define MG_EUNDEF 5 /* undefined reference */
59			#define MG_ENOFILE 6 /* cannot open input file */
60			#define MG_EINCL 7 /* error in included file */
61			#define MG_EMEM 8 /* out of memory */
62			#define MG_ESEEK 9 /* file seek error */
63	greg	1.2	#define MG_EBADMAT 10 /* bad material specification */
64	greg	1.1
65	greg	1.2	#define MG_NERRS 11
66	greg	1.1
67			extern char *mg_err[MG_NERRS];
68
69			/*
70			* The general process for running the parser is to fill in the mg_ehand
71			* array with handlers for each entity you know how to handle.
72			* Then, call mg_init to fill in the rest. This function will report
73			* an error and quit if you try to support an inconsistent set of entities.
74			* For each file you want to parse, call mg_load with the file name.
75			* To read from standard input, use NULL as the file name.
76			* For additional control over error reporting and file management,
77			* use mg_open, mg_read, mg_parse and mg_close instead of mg_load.
78			* To free any data structures and clear the parser, use mg_clear.
79			* If there is an error, mg_load, mg_open, mg_parse, and mg_rewind
80			* will return an error from the list above. In addition, mg_load
81			* will report the error to stderr. The mg_read routine returns 0
82			* when the end of file has been reached.
83			*/
84
85			#define MG_MAXLINE 512 /* maximum input line length */
86			#define MG_MAXARGC (MG_MAXLINE/4) /* maximum argument count */
87
88			typedef struct mg_fctxt {
89			char fname; / file name */
90			FILE fp; / stream pointer */
91			char inpline[MG_MAXLINE]; /* input line */
92			int lineno; /* line number */
93			struct mg_fctxt prev; / previous context */
94			} MG_FCTXT;
95
96			extern MG_FCTXT mg_file; / current file context */
97
98			#ifdef NOPROTO
99			extern void mg_init(); /* fill in mg_ehand array */
100			extern int mg_load(); /* parse a file */
101			extern int mg_open(); /* open new input file */
102			extern int mg_read(); /* read next line */
103			extern int mg_parse(); /* parse current line */
104			extern int mg_rewind(); /* rewind input file */
105			extern void mg_close(); /* close input file */
106			extern void mg_clear(); /* clear parser */
107			extern int mg_iterate();
108			#else
109			extern void mg_init(void); /* fill in mg_ehand array */
110			extern int mg_load(char ); / parse a file */
111			extern int mg_open(MG_FCTXT , char ); /* open new input file */
112			extern int mg_read(void); /* read next line */
113			extern int mg_parse(void); /* parse current line */
114			extern int mg_rewind(void); /* rewind input file */
115			extern void mg_close(void); /* close input file */
116			extern void mg_clear(void); /* clear parser */
117			extern int mg_iterate(int, char *, int ()(void));
118			#endif
119
120			#ifndef MG_NQCD
121			#define MG_NQCD 5 /* default number of divisions */
122			#endif
123
124			extern int mg_nqcdivs; /* divisions per quarter circle */
125
126			/*
127			* The following library routines are included for your convenience:
128			*/
129
130			#ifdef NOPROTO
131			extern int mg_entity(); /* get entity number from its name */
132			extern int isint(); /* non-zero if integer format */
133			extern int isflt(); /* non-zero if floating point format */
134			#else
135			extern int mg_entity(char ); / get entity number from its name */
136			extern int isint(char ); / non-zero if integer format */
137			extern int isflt(char ); / non-zero if floating point format */
138			#endif
139
140			/************************************************************************
141			* Definitions for 3-d vector manipulation functions
142			*/
143
144	greg	1.3	#ifdef SMLFLT
145			#define FLOAT float
146			#define FTINY (1e-3)
147	greg	1.2	#else
148	greg	1.3	#define FLOAT double
149			#define FTINY (1e-6)
150	greg	1.2	#endif
151	greg	1.3	#define FHUGE (1e10)
152	greg	1.1
153	greg	1.2	typedef FLOAT FVECT[3];
154
155	greg	1.3	#define VCOPY(v1,v2) ((v1)[0]=(v2)[0],(v1)[1]=(v2)[1],(v1)[2]=(v2)[2])
156			#define DOT(v1,v2) ((v1)[0](v2)[0]+(v1)[1](v2)[1]+(v1)[2]*(v2)[2])
157			#define VSUM(vr,v1,v2,f) ((vr)[0]=(v1)[0]+(f)*(v2)[0], \
158			(vr)[1]=(v1)[1]+(f)*(v2)[1], \
159			(vr)[2]=(v1)[2]+(f)*(v2)[2])
160
161			#define is0vect(v) (DOT(v,v) < FTINY*FTINY)
162
163			#define round0(x) if (x <= FTINY && x >= -FTINY) x = 0
164
165	greg	1.1	#ifdef NOPROTO
166			extern double normalize(); /* normalize a vector */
167			#else
168			extern double normalize(FVECT); /* normalize a vector */
169			#endif
170
171			/************************************************************************
172			* Definitions for context handling routines
173			* (materials, colors, vectors)
174			*/
175
176			typedef struct {
177	greg	1.2	float cx, cy; /* XY chromaticity coordinates */
178	greg	1.1	} C_COLOR; /* color context */
179
180			typedef struct {
181	greg	1.2	char name; / material name */
182			int clock; /* incremented each change -- resettable */
183			float rd; /* diffuse reflectance */
184	greg	1.1	C_COLOR rd_c; /* diffuse reflectance color */
185	greg	1.2	float td; /* diffuse transmittance */
186	greg	1.1	C_COLOR td_c; /* diffuse transmittance color */
187	greg	1.2	float ed; /* diffuse emittance */
188	greg	1.1	C_COLOR ed_c; /* diffuse emittance color */
189	greg	1.2	float rs; /* specular reflectance */
190	greg	1.1	C_COLOR rs_c; /* specular reflectance color */
191	greg	1.2	float rs_a; /* specular reflectance roughness */
192			float ts; /* specular transmittance */
193	greg	1.1	C_COLOR ts_c; /* specular transmittance color */
194	greg	1.2	float ts_a; /* specular transmittance roughness */
195	greg	1.1	} C_MATERIAL; /* material context */
196
197			typedef struct {
198			FVECT p, n; /* point and normal */
199			} C_VERTEX; /* vertex context */
200	greg	1.3
201			#define isgrey(cxy) ((cxy)->cx > .31 && (cxy)->cx < .35 && \
202			(cxy)->cy > .31 && (cxy)->cy < .35)
203	greg	1.1
204			#define C_DEFCOLOR {.333,.333}
205	greg	1.2	#define C_DEFMATERIAL {NULL,1,0.,C_DEFCOLOR,0.,C_DEFCOLOR,0.,C_DEFCOLOR,\
206			0.,C_DEFCOLOR,0.,0.,C_DEFCOLOR,0.}
207	greg	1.1	#define C_DEFVERTEX {{0.,0.,0.},{0.,0.,0.}}
208
209			extern C_COLOR c_ccolor; / the current color */
210			extern C_MATERIAL c_cmaterial; / the current material */
211			extern C_VERTEX c_cvertex; / the current vertex */
212
213			#ifdef NOPROTO
214			extern int c_hcolor(); /* handle color entity */
215			extern int c_hmaterial(); /* handle material entity */
216			extern int c_hvertex(); /* handle vertex entity */
217			extern void c_clearall(); /* clear context tables */
218			extern C_VERTEX c_getvert(); / get a named vertex */
219			#else
220			extern int c_hcolor(int, char *); / handle color entity */
221			extern int c_hmaterial(int, char *); / handle material entity */
222			extern int c_hvertex(int, char *); / handle vertex entity */
223			extern void c_clearall(void); /* clear context tables */
224			extern C_VERTEX c_getvert(char ); /* get a named vertex */
225			#endif
226
227			/*************************************************************************
228			* Definitions for hierarchical object name handler
229			*/
230
231			extern int obj_nnames; /* depth of name hierarchy */
232			extern char *obj_name; / names in hierarchy */
233
234			#ifdef NOPROTO
235			extern int obj_handler(); /* handle an object entity */
236	greg	1.2	extern void obj_clear(); /* clear object stack */
237	greg	1.1	#else
238			extern int obj_handler(int, char *); / handle an object entity */
239	greg	1.2	extern void obj_clear(void); /* clear object stack */
240	greg	1.1	#endif
241
242			/**************************************************************************
243			* Definitions for hierarchical transformation handler
244			*/
245
246	greg	1.2	typedef FLOAT MAT4[4][4];
247	greg	1.1
248			#ifdef BSD
249			#define copymat4(m4a,m4b) bcopy((char )m4b,(char )m4a,sizeof(MAT4))
250			#else
251			#define copymat4(m4a,m4b) (void)memcpy((char )m4a,(char )m4b,sizeof(MAT4))
252			extern char *memcpy();
253			#endif
254
255			#define MAT4IDENT { {1.,0.,0.,0.}, {0.,1.,0.,0.}, \
256			{0.,0.,1.,0.}, {0.,0.,0.,1.} }
257
258			extern MAT4 m4ident;
259
260			#define setident4(m4) copymat4(m4, m4ident)
261
262			/* regular transformation */
263			typedef struct {
264			MAT4 xfm; /* transform matrix */
265	greg	1.2	FLOAT sca; /* scalefactor */
266	greg	1.1	} XF;
267
268			#define identxf(xp) (void)(setident4((xp)->xfm),(xp)->sca=1.0)
269
270			typedef struct xf_spec {
271			short xac; /* transform argument count */
272			short xav0; /* zeroeth argument in xf_argv array */
273			XF xf; /* cumulative transformation */
274			struct xf_spec prev; / previous transformation context */
275			} XF_SPEC;
276
277			extern int xf_argc; /* total # transform args. */
278			extern char *xf_argv; / transform arguments */
279			extern XF_SPEC xf_context; / current context */
280
281			/*
282			* The transformation handler should do most of the work that needs
283			* doing. Just pass it any xf entities, then use the associated
284			* functions to transform and translate points, transform vectors
285			* (without translation), rotate vectors (without scaling) and scale
286			* values appropriately.
287			*
288			* The routines xf_xfmpoint, xf_xfmvect and xf_rotvect take two
289			* 3-D vectors (which may be identical), transforms the second and
290			* puts the result into the first.
291			*/
292
293			#ifdef NOPROTO
294
295			extern int xf_handler(); /* handle xf entity */
296			extern void xf_xfmpoint(); /* transform point */
297			extern void xf_xfmvect(); /* transform vector */
298			extern void xf_rotvect(); /* rotate vector */
299			extern double xf_scale(); /* scale a value */
300	greg	1.2	extern void xf_clear(); /* clear xf stack */
301	greg	1.1
302			/* The following are support routines you probably won't call directly */
303
304			extern void multmat4(); /* m4a = m4b X m4c */
305			extern void multv3(); /* v3a = v3b X m4 (vectors) */
306			extern void multp3(); /* p3a = p3b X m4 (points) */
307			extern int xf(); /* interpret transform spec. */
308
309			#else
310
311	greg	1.2	extern int xf_handler(int, char *); / handle xf entity */
312			extern void xf_xfmpoint(FVECT, FVECT); /* transform point */
313			extern void xf_xfmvect(FVECT, FVECT); /* transform vector */
314			extern void xf_rotvect(FVECT, FVECT); /* rotate vector */
315			extern double xf_scale(double); /* scale a value */
316			extern void xf_clear(void); /* clear xf stack */
317	greg	1.1
318			/* The following are support routines you probably won't call directly */
319
320			extern void multmat4(MAT4, MAT4, MAT4); /* m4a = m4b X m4c */
321			extern void multv3(FVECT, FVECT, MAT4); /* v3a = v3b X m4 (vectors) */
322			extern void multp3(FVECT, FVECT, MAT4); /* p3a = p3b X m4 (points) */
323			extern int xf(XF, int, char *); / interpret transform spec. */
324
325			#endif
326
327			/************************************************************************
328			* Miscellaneous definitions
329			*/
330
331			#ifdef M_PI
332			#define PI M_PI
333			#else
334			#define PI 3.14159265358979323846
335			#endif
336
337			#ifdef DCL_ATOF
338			extern double atof();
339			#endif
340
341			#ifndef MEM_PTR
342			#define MEM_PTR void *
343			#endif
344
345			extern MEM_PTR malloc();
346			extern MEM_PTR calloc();
347			extern MEM_PTR realloc();
348	greg	1.4	extern void free();