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root/radiance/ray/src/common/mgf_parser.c
Revision: 3.1
Committed: Fri Feb 18 00:40:25 2011 UTC (13 years, 2 months ago) by greg
Content type: text/plain
Branch: MAIN
CVS Tags: rad5R2, rad4R2P2, rad5R0, rad5R1, rad4R2, rad4R1, rad4R2P1
Log Message:
Major code reorg, moving mgflib to common and introducing BSDF material

File Contents

# User Rev Content
1 greg 3.1 #ifndef lint
2     static const char RCSid[] = "$Id: parser.c,v 1.28 2003/11/15 17:54:06 schorsch Exp $";
3     #endif
4     /*
5     * Parse an MGF file, converting or discarding unsupported entities
6     */
7    
8     #include <stdio.h>
9     #include <stdlib.h>
10     #include <math.h>
11     #include <ctype.h>
12     #include <string.h>
13     #include "mgf_parser.h"
14     #include "lookup.h"
15     #include "mgf_mesg.h"
16    
17     /*
18     * Global definitions of variables declared in parser.h
19     */
20     /* entity names */
21    
22     char mg_ename[MG_NENTITIES][MG_MAXELEN] = MG_NAMELIST;
23    
24     /* Handler routines for each entity */
25    
26     int (*mg_ehand[MG_NENTITIES])();
27    
28     /* Handler routine for unknown entities */
29    
30     int (*mg_uhand)() = mg_defuhand;
31    
32     unsigned mg_nunknown; /* count of unknown entities */
33    
34     /* error messages */
35    
36     char *mg_err[MG_NERRS] = MG_ERRLIST;
37    
38     MG_FCTXT *mg_file; /* current file context pointer */
39    
40     int mg_nqcdivs = MG_NQCD; /* number of divisions per quarter circle */
41    
42     /*
43     * The idea with this parser is to compensate for any missing entries in
44     * mg_ehand with alternate handlers that express these entities in terms
45     * of others that the calling program can handle.
46     *
47     * In some cases, no alternate handler is possible because the entity
48     * has no approximate equivalent. These entities are simply discarded.
49     *
50     * Certain entities are dependent on others, and mg_init() will fail
51     * if the supported entities are not consistent.
52     *
53     * Some alternate entity handlers require that earlier entities be
54     * noted in some fashion, and we therefore keep another array of
55     * parallel support handlers to assist in this effort.
56     */
57    
58     /* temporary settings for testing */
59     #define e_ies e_any_toss
60     /* alternate handler routines */
61    
62     static void make_axes(FVECT u, FVECT v, FVECT w);
63     static int put_cxy(void);
64     static int put_cspec(void);
65    
66     static int e_any_toss(int ac, char **av); /* discard an unwanted entity */
67     static int e_cspec(int ac, char **av); /* handle spectral color */
68     static int e_cmix(int ac, char **av); /* handle mixing of colors */
69     static int e_cct(int ac, char **av); /* handle color temperature */
70    
71    
72     /* alternate handler support functions */
73    
74     static int (*e_supp[MG_NENTITIES])(int ac, char **av);
75    
76     static char FLTFMT[] = "%.12g";
77    
78     static int warpconends; /* hack for generating good normals */
79    
80    
81     void
82     mg_init(void) /* initialize alternate entity handlers */
83     {
84     unsigned long ineed = 0, uneed = 0;
85     register int i;
86     /* pick up slack */
87     if (mg_ehand[MG_E_IES] == NULL)
88     mg_ehand[MG_E_IES] = e_ies;
89     if (mg_ehand[MG_E_INCLUDE] == NULL)
90     mg_ehand[MG_E_INCLUDE] = e_include;
91     if (mg_ehand[MG_E_SPH] == NULL) {
92     mg_ehand[MG_E_SPH] = e_sph;
93     ineed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX;
94     } else
95     uneed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX|1L<<MG_E_XF;
96     if (mg_ehand[MG_E_CYL] == NULL) {
97     mg_ehand[MG_E_CYL] = e_cyl;
98     ineed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX;
99     } else
100     uneed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX|1L<<MG_E_XF;
101     if (mg_ehand[MG_E_CONE] == NULL) {
102     mg_ehand[MG_E_CONE] = e_cone;
103     ineed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX;
104     } else
105     uneed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX|1L<<MG_E_XF;
106     if (mg_ehand[MG_E_RING] == NULL) {
107     mg_ehand[MG_E_RING] = e_ring;
108     ineed |= 1L<<MG_E_POINT|1L<<MG_E_NORMAL|1L<<MG_E_VERTEX;
109     } else
110     uneed |= 1L<<MG_E_POINT|1L<<MG_E_NORMAL|1L<<MG_E_VERTEX|1L<<MG_E_XF;
111     if (mg_ehand[MG_E_PRISM] == NULL) {
112     mg_ehand[MG_E_PRISM] = e_prism;
113     ineed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX;
114     } else
115     uneed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX|1L<<MG_E_XF;
116     if (mg_ehand[MG_E_TORUS] == NULL) {
117     mg_ehand[MG_E_TORUS] = e_torus;
118     ineed |= 1L<<MG_E_POINT|1L<<MG_E_NORMAL|1L<<MG_E_VERTEX;
119     } else
120     uneed |= 1L<<MG_E_POINT|1L<<MG_E_NORMAL|1L<<MG_E_VERTEX|1L<<MG_E_XF;
121     if (mg_ehand[MG_E_FACE] == NULL)
122     mg_ehand[MG_E_FACE] = mg_ehand[MG_E_FACEH];
123     else if (mg_ehand[MG_E_FACEH] == NULL)
124     mg_ehand[MG_E_FACEH] = e_faceh;
125     if (mg_ehand[MG_E_COLOR] != NULL) {
126     if (mg_ehand[MG_E_CMIX] == NULL) {
127     mg_ehand[MG_E_CMIX] = e_cmix;
128     ineed |= 1L<<MG_E_COLOR|1L<<MG_E_CXY|1L<<MG_E_CSPEC|1L<<MG_E_CMIX|1L<<MG_E_CCT;
129     }
130     if (mg_ehand[MG_E_CSPEC] == NULL) {
131     mg_ehand[MG_E_CSPEC] = e_cspec;
132     ineed |= 1L<<MG_E_COLOR|1L<<MG_E_CXY|1L<<MG_E_CSPEC|1L<<MG_E_CMIX|1L<<MG_E_CCT;
133     }
134     if (mg_ehand[MG_E_CCT] == NULL) {
135     mg_ehand[MG_E_CCT] = e_cct;
136     ineed |= 1L<<MG_E_COLOR|1L<<MG_E_CXY|1L<<MG_E_CSPEC|1L<<MG_E_CMIX|1L<<MG_E_CCT;
137     }
138     }
139     /* check for consistency */
140     if (mg_ehand[MG_E_FACE] != NULL)
141     uneed |= 1L<<MG_E_POINT|1L<<MG_E_VERTEX|1L<<MG_E_XF;
142     if (mg_ehand[MG_E_CXY] != NULL || mg_ehand[MG_E_CSPEC] != NULL ||
143     mg_ehand[MG_E_CMIX] != NULL)
144     uneed |= 1L<<MG_E_COLOR;
145     if (mg_ehand[MG_E_RD] != NULL || mg_ehand[MG_E_TD] != NULL ||
146     mg_ehand[MG_E_IR] != NULL ||
147     mg_ehand[MG_E_ED] != NULL ||
148     mg_ehand[MG_E_RS] != NULL ||
149     mg_ehand[MG_E_TS] != NULL ||
150     mg_ehand[MG_E_SIDES] != NULL)
151     uneed |= 1L<<MG_E_MATERIAL;
152     for (i = 0; i < MG_NENTITIES; i++)
153     if (uneed & 1L<<i && mg_ehand[i] == NULL) {
154     fprintf(stderr, "Missing support for \"%s\" entity\n",
155     mg_ename[i]);
156     exit(1);
157     }
158     /* add support as needed */
159     if (ineed & 1L<<MG_E_VERTEX && mg_ehand[MG_E_VERTEX] != c_hvertex)
160     e_supp[MG_E_VERTEX] = c_hvertex;
161     if (ineed & 1L<<MG_E_POINT && mg_ehand[MG_E_POINT] != c_hvertex)
162     e_supp[MG_E_POINT] = c_hvertex;
163     if (ineed & 1L<<MG_E_NORMAL && mg_ehand[MG_E_NORMAL] != c_hvertex)
164     e_supp[MG_E_NORMAL] = c_hvertex;
165     if (ineed & 1L<<MG_E_COLOR && mg_ehand[MG_E_COLOR] != c_hcolor)
166     e_supp[MG_E_COLOR] = c_hcolor;
167     if (ineed & 1L<<MG_E_CXY && mg_ehand[MG_E_CXY] != c_hcolor)
168     e_supp[MG_E_CXY] = c_hcolor;
169     if (ineed & 1L<<MG_E_CSPEC && mg_ehand[MG_E_CSPEC] != c_hcolor)
170     e_supp[MG_E_CSPEC] = c_hcolor;
171     if (ineed & 1L<<MG_E_CMIX && mg_ehand[MG_E_CMIX] != c_hcolor)
172     e_supp[MG_E_CMIX] = c_hcolor;
173     if (ineed & 1L<<MG_E_CCT && mg_ehand[MG_E_CCT] != c_hcolor)
174     e_supp[MG_E_CCT] = c_hcolor;
175     /* discard remaining entities */
176     for (i = 0; i < MG_NENTITIES; i++)
177     if (mg_ehand[i] == NULL)
178     mg_ehand[i] = e_any_toss;
179     }
180    
181    
182     int
183     mg_entity( /* get entity number from its name */
184     char *name
185     )
186     {
187     static LUTAB ent_tab = LU_SINIT(NULL,NULL); /* lookup table */
188     register char *cp;
189    
190     if (!ent_tab.tsiz) { /* initialize hash table */
191     if (!lu_init(&ent_tab, MG_NENTITIES))
192     return(-1); /* what to do? */
193     for (cp = mg_ename[MG_NENTITIES-1]; cp >= mg_ename[0];
194     cp -= sizeof(mg_ename[0]))
195     lu_find(&ent_tab, cp)->key = cp;
196     }
197     cp = lu_find(&ent_tab, name)->key;
198     if (cp == NULL)
199     return(-1);
200     return((cp - mg_ename[0])/sizeof(mg_ename[0]));
201     }
202    
203    
204     int
205     mg_handle( /* pass entity to appropriate handler */
206     register int en,
207     int ac,
208     char **av
209     )
210     {
211     int rv;
212    
213     if (en < 0 && (en = mg_entity(av[0])) < 0) { /* unknown entity */
214     if (mg_uhand != NULL)
215     return((*mg_uhand)(ac, av));
216     return(MG_EUNK);
217     }
218     if (e_supp[en] != NULL) { /* support handler */
219     if ((rv = (*e_supp[en])(ac, av)) != MG_OK)
220     return(rv);
221     }
222     return((*mg_ehand[en])(ac, av)); /* assigned handler */
223     }
224    
225    
226     int
227     mg_open( /* open new input file */
228     register MG_FCTXT *ctx,
229     char *fn
230     )
231     {
232     static int nfids;
233     register char *cp;
234    
235     ctx->fid = ++nfids;
236     ctx->lineno = 0;
237     if (fn == NULL) {
238     strcpy(ctx->fname, "<stdin>");
239     ctx->fp = stdin;
240     ctx->prev = mg_file;
241     mg_file = ctx;
242     return(MG_OK);
243     }
244     /* get name relative to this context */
245     if (fn[0] != '/' && mg_file != NULL &&
246     (cp = strrchr(mg_file->fname, '/')) != NULL) {
247     strcpy(ctx->fname, mg_file->fname);
248     strcpy(ctx->fname+(cp-mg_file->fname+1), fn);
249     } else
250     strcpy(ctx->fname, fn);
251     ctx->fp = fopen(ctx->fname, "r");
252     if (ctx->fp == NULL)
253     return(MG_ENOFILE);
254     ctx->prev = mg_file; /* establish new context */
255     mg_file = ctx;
256     return(MG_OK);
257     }
258    
259    
260     void
261     mg_close(void) /* close input file */
262     {
263     register MG_FCTXT *ctx = mg_file;
264    
265     mg_file = ctx->prev; /* restore enclosing context */
266     if (ctx->fp != stdin) /* close file if it's a file */
267     fclose(ctx->fp);
268     }
269    
270    
271     void
272     mg_fgetpos( /* get current position in input file */
273     register MG_FPOS *pos
274     )
275     {
276     pos->fid = mg_file->fid;
277     pos->lineno = mg_file->lineno;
278     pos->offset = ftell(mg_file->fp);
279     }
280    
281    
282     int
283     mg_fgoto( /* reposition input file pointer */
284     register MG_FPOS *pos
285     )
286     {
287     if (pos->fid != mg_file->fid)
288     return(MG_ESEEK);
289     if (pos->lineno == mg_file->lineno)
290     return(MG_OK);
291     if (mg_file->fp == stdin)
292     return(MG_ESEEK); /* cannot seek on standard input */
293     if (fseek(mg_file->fp, pos->offset, 0) == EOF)
294     return(MG_ESEEK);
295     mg_file->lineno = pos->lineno;
296     return(MG_OK);
297     }
298    
299    
300     int
301     mg_read(void) /* read next line from file */
302     {
303     register int len = 0;
304    
305     do {
306     if (fgets(mg_file->inpline+len,
307     MG_MAXLINE-len, mg_file->fp) == NULL)
308     return(len);
309     len += strlen(mg_file->inpline+len);
310     if (len >= MG_MAXLINE-1)
311     return(len);
312     mg_file->lineno++;
313     } while (len > 1 && mg_file->inpline[len-2] == '\\');
314    
315     return(len);
316     }
317    
318    
319     int
320     mg_parse(void) /* parse current input line */
321     {
322     char abuf[MG_MAXLINE];
323     char *argv[MG_MAXARGC];
324     register char *cp, *cp2, **ap;
325     /* copy line, removing escape chars */
326     cp = abuf; cp2 = mg_file->inpline;
327     while ((*cp++ = *cp2++))
328     if (cp2[0] == '\n' && cp2[-1] == '\\')
329     cp--;
330     cp = abuf; ap = argv; /* break into words */
331     for ( ; ; ) {
332     while (isspace(*cp))
333     *cp++ = '\0';
334     if (!*cp)
335     break;
336     if (ap - argv >= MG_MAXARGC-1)
337     return(MG_EARGC);
338     *ap++ = cp;
339     while (*++cp && !isspace(*cp))
340     ;
341     }
342     if (ap == argv)
343     return(MG_OK); /* no words in line */
344     *ap = NULL;
345     /* else handle it */
346     return(mg_handle(-1, ap-argv, argv));
347     }
348    
349    
350     int
351     mg_load( /* load an MGF file */
352     char *fn
353     )
354     {
355     MG_FCTXT cntxt;
356     int rval;
357     register int nbr;
358    
359     if ((rval = mg_open(&cntxt, fn)) != MG_OK) {
360     fprintf(stderr, "%s: %s\n", fn, mg_err[rval]);
361     return(rval);
362     }
363     while ((nbr = mg_read()) > 0) { /* parse each line */
364     if (nbr >= MG_MAXLINE-1) {
365     fprintf(stderr, "%s: %d: %s\n", cntxt.fname,
366     cntxt.lineno, mg_err[rval=MG_ELINE]);
367     break;
368     }
369     if ((rval = mg_parse()) != MG_OK) {
370     fprintf(stderr, "%s: %d: %s:\n%s", cntxt.fname,
371     cntxt.lineno, mg_err[rval],
372     cntxt.inpline);
373     break;
374     }
375     }
376     mg_close();
377     return(rval);
378     }
379    
380    
381     int
382     mg_defuhand( /* default handler for unknown entities */
383     int ac,
384     char **av
385     )
386     {
387     if (mg_nunknown++ == 0) /* report first incident */
388     fprintf(stderr, "%s: %d: %s: %s\n", mg_file->fname,
389     mg_file->lineno, mg_err[MG_EUNK], av[0]);
390     return(MG_OK);
391     }
392    
393    
394     void
395     mg_clear(void) /* clear parser history */
396     {
397     c_clearall(); /* clear context tables */
398     while (mg_file != NULL) /* reset our file context */
399     mg_close();
400     }
401    
402    
403     /****************************************************************************
404     * The following routines handle unsupported entities
405     */
406    
407    
408     static int
409     e_any_toss( /* discard an unwanted entity */
410     int ac,
411     char **av
412     )
413     {
414     return(MG_OK);
415     }
416    
417    
418     int
419     e_include( /* include file */
420     int ac,
421     char **av
422     )
423     {
424     char *xfarg[MG_MAXARGC];
425     MG_FCTXT ictx;
426     XF_SPEC *xf_orig = xf_context;
427     register int rv;
428    
429     if (ac < 2)
430     return(MG_EARGC);
431     if ((rv = mg_open(&ictx, av[1])) != MG_OK)
432     return(rv);
433     if (ac > 2) {
434     register int i;
435    
436     xfarg[0] = mg_ename[MG_E_XF];
437     for (i = 1; i < ac-1; i++)
438     xfarg[i] = av[i+1];
439     xfarg[ac-1] = NULL;
440     if ((rv = mg_handle(MG_E_XF, ac-1, xfarg)) != MG_OK) {
441     mg_close();
442     return(rv);
443     }
444     }
445     do {
446     while ((rv = mg_read()) > 0) {
447     if (rv >= MG_MAXLINE-1) {
448     fprintf(stderr, "%s: %d: %s\n", ictx.fname,
449     ictx.lineno, mg_err[MG_ELINE]);
450     mg_close();
451     return(MG_EINCL);
452     }
453     if ((rv = mg_parse()) != MG_OK) {
454     fprintf(stderr, "%s: %d: %s:\n%s", ictx.fname,
455     ictx.lineno, mg_err[rv],
456     ictx.inpline);
457     mg_close();
458     return(MG_EINCL);
459     }
460     }
461     if (ac > 2)
462     if ((rv = mg_handle(MG_E_XF, 1, xfarg)) != MG_OK) {
463     mg_close();
464     return(rv);
465     }
466     } while (xf_context != xf_orig);
467     mg_close();
468     return(MG_OK);
469     }
470    
471    
472     int
473     e_faceh( /* replace face+holes with single contour */
474     int ac,
475     char **av
476     )
477     {
478     char *newav[MG_MAXARGC];
479     int lastp = 0;
480     register int i, j;
481    
482     newav[0] = mg_ename[MG_E_FACE];
483     for (i = 1; i < ac; i++)
484     if (av[i][0] == '-') {
485     if (i < 4)
486     return(MG_EARGC);
487     if (i >= ac-1)
488     break;
489     if (!lastp)
490     lastp = i-1;
491     for (j = i+1; j < ac-1 && av[j+1][0] != '-'; j++)
492     ;
493     if (j - i < 3)
494     return(MG_EARGC);
495     newav[i] = av[j]; /* connect hole loop */
496     } else
497     newav[i] = av[i]; /* hole or perimeter vertex */
498     if (lastp)
499     newav[i++] = av[lastp]; /* finish seam to outside */
500     newav[i] = NULL;
501     return(mg_handle(MG_E_FACE, i, newav));
502     }
503    
504    
505     static void
506     make_axes( /* compute u and v given w (normalized) */
507     FVECT u,
508     FVECT v,
509     FVECT w
510     )
511     {
512     register int i;
513    
514     v[0] = v[1] = v[2] = 0.;
515     for (i = 0; i < 3; i++)
516     if (w[i] < .6 && w[i] > -.6)
517     break;
518     v[i] = 1.;
519     fcross(u, v, w);
520     normalize(u);
521     fcross(v, w, u);
522     }
523    
524    
525     int
526     e_sph( /* expand a sphere into cones */
527     int ac,
528     char **av
529     )
530     {
531     static char p2x[24], p2y[24], p2z[24], r1[24], r2[24];
532     static char *v1ent[5] = {mg_ename[MG_E_VERTEX],"_sv1","=","_sv2"};
533     static char *v2ent[4] = {mg_ename[MG_E_VERTEX],"_sv2","="};
534     static char *p2ent[5] = {mg_ename[MG_E_POINT],p2x,p2y,p2z};
535     static char *conent[6] = {mg_ename[MG_E_CONE],"_sv1",r1,"_sv2",r2};
536     register C_VERTEX *cv;
537     register int i;
538     int rval;
539     double rad;
540     double theta;
541    
542     if (ac != 3)
543     return(MG_EARGC);
544     if ((cv = c_getvert(av[1])) == NULL)
545     return(MG_EUNDEF);
546     if (!isflt(av[2]))
547     return(MG_ETYPE);
548     rad = atof(av[2]);
549     /* initialize */
550     warpconends = 1;
551     if ((rval = mg_handle(MG_E_VERTEX, 3, v2ent)) != MG_OK)
552     return(rval);
553     sprintf(p2x, FLTFMT, cv->p[0]);
554     sprintf(p2y, FLTFMT, cv->p[1]);
555     sprintf(p2z, FLTFMT, cv->p[2]+rad);
556     if ((rval = mg_handle(MG_E_POINT, 4, p2ent)) != MG_OK)
557     return(rval);
558     r2[0] = '0'; r2[1] = '\0';
559     for (i = 1; i <= 2*mg_nqcdivs; i++) {
560     theta = i*(PI/2)/mg_nqcdivs;
561     if ((rval = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
562     return(rval);
563     sprintf(p2z, FLTFMT, cv->p[2]+rad*cos(theta));
564     if ((rval = mg_handle(MG_E_VERTEX, 2, v2ent)) != MG_OK)
565     return(rval);
566     if ((rval = mg_handle(MG_E_POINT, 4, p2ent)) != MG_OK)
567     return(rval);
568     strcpy(r1, r2);
569     sprintf(r2, FLTFMT, rad*sin(theta));
570     if ((rval = mg_handle(MG_E_CONE, 5, conent)) != MG_OK)
571     return(rval);
572     }
573     warpconends = 0;
574     return(MG_OK);
575     }
576    
577    
578     int
579     e_torus( /* expand a torus into cones */
580     int ac,
581     char **av
582     )
583     {
584     static char p2[3][24], r1[24], r2[24];
585     static char *v1ent[5] = {mg_ename[MG_E_VERTEX],"_tv1","=","_tv2"};
586     static char *v2ent[5] = {mg_ename[MG_E_VERTEX],"_tv2","="};
587     static char *p2ent[5] = {mg_ename[MG_E_POINT],p2[0],p2[1],p2[2]};
588     static char *conent[6] = {mg_ename[MG_E_CONE],"_tv1",r1,"_tv2",r2};
589     register C_VERTEX *cv;
590     register int i, j;
591     int rval;
592     int sgn;
593     double minrad, maxrad, avgrad;
594     double theta;
595    
596     if (ac != 4)
597     return(MG_EARGC);
598     if ((cv = c_getvert(av[1])) == NULL)
599     return(MG_EUNDEF);
600     if (is0vect(cv->n))
601     return(MG_EILL);
602     if (!isflt(av[2]) || !isflt(av[3]))
603     return(MG_ETYPE);
604     minrad = atof(av[2]);
605     round0(minrad);
606     maxrad = atof(av[3]);
607     /* check orientation */
608     if (minrad > 0.)
609     sgn = 1;
610     else if (minrad < 0.)
611     sgn = -1;
612     else if (maxrad > 0.)
613     sgn = 1;
614     else if (maxrad < 0.)
615     sgn = -1;
616     else
617     return(MG_EILL);
618     if (sgn*(maxrad-minrad) <= 0.)
619     return(MG_EILL);
620     /* initialize */
621     warpconends = 1;
622     v2ent[3] = av[1];
623     for (j = 0; j < 3; j++)
624     sprintf(p2[j], FLTFMT, cv->p[j] +
625     .5*sgn*(maxrad-minrad)*cv->n[j]);
626     if ((rval = mg_handle(MG_E_VERTEX, 4, v2ent)) != MG_OK)
627     return(rval);
628     if ((rval = mg_handle(MG_E_POINT, 4, p2ent)) != MG_OK)
629     return(rval);
630     sprintf(r2, FLTFMT, avgrad=.5*(minrad+maxrad));
631     /* run outer section */
632     for (i = 1; i <= 2*mg_nqcdivs; i++) {
633     theta = i*(PI/2)/mg_nqcdivs;
634     if ((rval = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
635     return(rval);
636     for (j = 0; j < 3; j++)
637     sprintf(p2[j], FLTFMT, cv->p[j] +
638     .5*sgn*(maxrad-minrad)*cos(theta)*cv->n[j]);
639     if ((rval = mg_handle(MG_E_VERTEX, 2, v2ent)) != MG_OK)
640     return(rval);
641     if ((rval = mg_handle(MG_E_POINT, 4, p2ent)) != MG_OK)
642     return(rval);
643     strcpy(r1, r2);
644     sprintf(r2, FLTFMT, avgrad + .5*(maxrad-minrad)*sin(theta));
645     if ((rval = mg_handle(MG_E_CONE, 5, conent)) != MG_OK)
646     return(rval);
647     }
648     /* run inner section */
649     sprintf(r2, FLTFMT, -.5*(minrad+maxrad));
650     for ( ; i <= 4*mg_nqcdivs; i++) {
651     theta = i*(PI/2)/mg_nqcdivs;
652     for (j = 0; j < 3; j++)
653     sprintf(p2[j], FLTFMT, cv->p[j] +
654     .5*sgn*(maxrad-minrad)*cos(theta)*cv->n[j]);
655     if ((rval = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
656     return(rval);
657     if ((rval = mg_handle(MG_E_VERTEX, 2, v2ent)) != MG_OK)
658     return(rval);
659     if ((rval = mg_handle(MG_E_POINT, 4, p2ent)) != MG_OK)
660     return(rval);
661     strcpy(r1, r2);
662     sprintf(r2, FLTFMT, -avgrad - .5*(maxrad-minrad)*sin(theta));
663     if ((rval = mg_handle(MG_E_CONE, 5, conent)) != MG_OK)
664     return(rval);
665     }
666     warpconends = 0;
667     return(MG_OK);
668     }
669    
670    
671     int
672     e_cyl( /* replace a cylinder with equivalent cone */
673     int ac,
674     char **av
675     )
676     {
677     static char *avnew[6] = {mg_ename[MG_E_CONE]};
678    
679     if (ac != 4)
680     return(MG_EARGC);
681     avnew[1] = av[1];
682     avnew[2] = av[2];
683     avnew[3] = av[3];
684     avnew[4] = av[2];
685     return(mg_handle(MG_E_CONE, 5, avnew));
686     }
687    
688    
689     int
690     e_ring( /* turn a ring into polygons */
691     int ac,
692     char **av
693     )
694     {
695     static char p3[3][24], p4[3][24];
696     static char *nzent[5] = {mg_ename[MG_E_NORMAL],"0","0","0"};
697     static char *v1ent[5] = {mg_ename[MG_E_VERTEX],"_rv1","="};
698     static char *v2ent[5] = {mg_ename[MG_E_VERTEX],"_rv2","=","_rv3"};
699     static char *v3ent[4] = {mg_ename[MG_E_VERTEX],"_rv3","="};
700     static char *p3ent[5] = {mg_ename[MG_E_POINT],p3[0],p3[1],p3[2]};
701     static char *v4ent[4] = {mg_ename[MG_E_VERTEX],"_rv4","="};
702     static char *p4ent[5] = {mg_ename[MG_E_POINT],p4[0],p4[1],p4[2]};
703     static char *fent[6] = {mg_ename[MG_E_FACE],"_rv1","_rv2","_rv3","_rv4"};
704     register C_VERTEX *cv;
705     register int i, j;
706     FVECT u, v;
707     double minrad, maxrad;
708     int rv;
709     double theta, d;
710    
711     if (ac != 4)
712     return(MG_EARGC);
713     if ((cv = c_getvert(av[1])) == NULL)
714     return(MG_EUNDEF);
715     if (is0vect(cv->n))
716     return(MG_EILL);
717     if (!isflt(av[2]) || !isflt(av[3]))
718     return(MG_ETYPE);
719     minrad = atof(av[2]);
720     round0(minrad);
721     maxrad = atof(av[3]);
722     if (minrad < 0. || maxrad <= minrad)
723     return(MG_EILL);
724     /* initialize */
725     make_axes(u, v, cv->n);
726     for (j = 0; j < 3; j++)
727     sprintf(p3[j], FLTFMT, cv->p[j] + maxrad*u[j]);
728     if ((rv = mg_handle(MG_E_VERTEX, 3, v3ent)) != MG_OK)
729     return(rv);
730     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
731     return(rv);
732     if (minrad == 0.) { /* closed */
733     v1ent[3] = av[1];
734     if ((rv = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
735     return(rv);
736     if ((rv = mg_handle(MG_E_NORMAL, 4, nzent)) != MG_OK)
737     return(rv);
738     for (i = 1; i <= 4*mg_nqcdivs; i++) {
739     theta = i*(PI/2)/mg_nqcdivs;
740     if ((rv = mg_handle(MG_E_VERTEX, 4, v2ent)) != MG_OK)
741     return(rv);
742     for (j = 0; j < 3; j++)
743     sprintf(p3[j], FLTFMT, cv->p[j] +
744     maxrad*u[j]*cos(theta) +
745     maxrad*v[j]*sin(theta));
746     if ((rv = mg_handle(MG_E_VERTEX, 2, v3ent)) != MG_OK)
747     return(rv);
748     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
749     return(rv);
750     if ((rv = mg_handle(MG_E_FACE, 4, fent)) != MG_OK)
751     return(rv);
752     }
753     } else { /* open */
754     if ((rv = mg_handle(MG_E_VERTEX, 3, v4ent)) != MG_OK)
755     return(rv);
756     for (j = 0; j < 3; j++)
757     sprintf(p4[j], FLTFMT, cv->p[j] + minrad*u[j]);
758     if ((rv = mg_handle(MG_E_POINT, 4, p4ent)) != MG_OK)
759     return(rv);
760     v1ent[3] = "_rv4";
761     for (i = 1; i <= 4*mg_nqcdivs; i++) {
762     theta = i*(PI/2)/mg_nqcdivs;
763     if ((rv = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
764     return(rv);
765     if ((rv = mg_handle(MG_E_VERTEX, 4, v2ent)) != MG_OK)
766     return(rv);
767     for (j = 0; j < 3; j++) {
768     d = u[j]*cos(theta) + v[j]*sin(theta);
769     sprintf(p3[j], FLTFMT, cv->p[j] + maxrad*d);
770     sprintf(p4[j], FLTFMT, cv->p[j] + minrad*d);
771     }
772     if ((rv = mg_handle(MG_E_VERTEX, 2, v3ent)) != MG_OK)
773     return(rv);
774     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
775     return(rv);
776     if ((rv = mg_handle(MG_E_VERTEX, 2, v4ent)) != MG_OK)
777     return(rv);
778     if ((rv = mg_handle(MG_E_POINT, 4, p4ent)) != MG_OK)
779     return(rv);
780     if ((rv = mg_handle(MG_E_FACE, 5, fent)) != MG_OK)
781     return(rv);
782     }
783     }
784     return(MG_OK);
785     }
786    
787    
788     int
789     e_cone( /* turn a cone into polygons */
790     int ac,
791     char **av
792     )
793     {
794     static char p3[3][24], p4[3][24], n3[3][24], n4[3][24];
795     static char *v1ent[5] = {mg_ename[MG_E_VERTEX],"_cv1","="};
796     static char *v2ent[5] = {mg_ename[MG_E_VERTEX],"_cv2","=","_cv3"};
797     static char *v3ent[4] = {mg_ename[MG_E_VERTEX],"_cv3","="};
798     static char *p3ent[5] = {mg_ename[MG_E_POINT],p3[0],p3[1],p3[2]};
799     static char *n3ent[5] = {mg_ename[MG_E_NORMAL],n3[0],n3[1],n3[2]};
800     static char *v4ent[4] = {mg_ename[MG_E_VERTEX],"_cv4","="};
801     static char *p4ent[5] = {mg_ename[MG_E_POINT],p4[0],p4[1],p4[2]};
802     static char *n4ent[5] = {mg_ename[MG_E_NORMAL],n4[0],n4[1],n4[2]};
803     static char *fent[6] = {mg_ename[MG_E_FACE],"_cv1","_cv2","_cv3","_cv4"};
804     char *v1n;
805     register C_VERTEX *cv1, *cv2;
806     register int i, j;
807     FVECT u, v, w;
808     double rad1, rad2;
809     int sgn;
810     double n1off, n2off;
811     double d;
812     int rv;
813     double theta;
814    
815     if (ac != 5)
816     return(MG_EARGC);
817     if ((cv1 = c_getvert(av[1])) == NULL ||
818     (cv2 = c_getvert(av[3])) == NULL)
819     return(MG_EUNDEF);
820     v1n = av[1];
821     if (!isflt(av[2]) || !isflt(av[4]))
822     return(MG_ETYPE);
823     rad1 = atof(av[2]);
824     round0(rad1);
825     rad2 = atof(av[4]);
826     round0(rad2);
827     if (rad1 == 0.) {
828     if (rad2 == 0.)
829     return(MG_EILL);
830     } else if (rad2 != 0.) {
831     if ((rad1 < 0.) ^ (rad2 < 0.))
832     return(MG_EILL);
833     } else { /* swap */
834     C_VERTEX *cv;
835    
836     cv = cv1;
837     cv1 = cv2;
838     cv2 = cv;
839     v1n = av[3];
840     d = rad1;
841     rad1 = rad2;
842     rad2 = d;
843     }
844     sgn = rad2 < 0. ? -1 : 1;
845     /* initialize */
846     for (j = 0; j < 3; j++)
847     w[j] = cv1->p[j] - cv2->p[j];
848     if ((d = normalize(w)) == 0.)
849     return(MG_EILL);
850     n1off = n2off = (rad2 - rad1)/d;
851     if (warpconends) { /* hack for e_sph and e_torus */
852     d = atan(n2off) - (PI/4)/mg_nqcdivs;
853     if (d <= -PI/2+FTINY)
854     n2off = -FHUGE;
855     else
856     n2off = tan(d);
857     }
858     make_axes(u, v, w);
859     for (j = 0; j < 3; j++) {
860     sprintf(p3[j], FLTFMT, cv2->p[j] + rad2*u[j]);
861     if (n2off <= -FHUGE)
862     sprintf(n3[j], FLTFMT, -w[j]);
863     else
864     sprintf(n3[j], FLTFMT, u[j] + w[j]*n2off);
865     }
866     if ((rv = mg_handle(MG_E_VERTEX, 3, v3ent)) != MG_OK)
867     return(rv);
868     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
869     return(rv);
870     if ((rv = mg_handle(MG_E_NORMAL, 4, n3ent)) != MG_OK)
871     return(rv);
872     if (rad1 == 0.) { /* triangles */
873     v1ent[3] = v1n;
874     if ((rv = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
875     return(rv);
876     for (j = 0; j < 3; j++)
877     sprintf(n4[j], FLTFMT, w[j]);
878     if ((rv = mg_handle(MG_E_NORMAL, 4, n4ent)) != MG_OK)
879     return(rv);
880     for (i = 1; i <= 4*mg_nqcdivs; i++) {
881     theta = sgn*i*(PI/2)/mg_nqcdivs;
882     if ((rv = mg_handle(MG_E_VERTEX, 4, v2ent)) != MG_OK)
883     return(rv);
884     for (j = 0; j < 3; j++) {
885     d = u[j]*cos(theta) + v[j]*sin(theta);
886     sprintf(p3[j], FLTFMT, cv2->p[j] + rad2*d);
887     if (n2off > -FHUGE)
888     sprintf(n3[j], FLTFMT, d + w[j]*n2off);
889     }
890     if ((rv = mg_handle(MG_E_VERTEX, 2, v3ent)) != MG_OK)
891     return(rv);
892     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
893     return(rv);
894     if (n2off > -FHUGE &&
895     (rv = mg_handle(MG_E_NORMAL, 4, n3ent)) != MG_OK)
896     return(rv);
897     if ((rv = mg_handle(MG_E_FACE, 4, fent)) != MG_OK)
898     return(rv);
899     }
900     } else { /* quads */
901     v1ent[3] = "_cv4";
902     if (warpconends) { /* hack for e_sph and e_torus */
903     d = atan(n1off) + (PI/4)/mg_nqcdivs;
904     if (d >= PI/2-FTINY)
905     n1off = FHUGE;
906     else
907     n1off = tan(atan(n1off)+(PI/4)/mg_nqcdivs);
908     }
909     for (j = 0; j < 3; j++) {
910     sprintf(p4[j], FLTFMT, cv1->p[j] + rad1*u[j]);
911     if (n1off >= FHUGE)
912     sprintf(n4[j], FLTFMT, w[j]);
913     else
914     sprintf(n4[j], FLTFMT, u[j] + w[j]*n1off);
915     }
916     if ((rv = mg_handle(MG_E_VERTEX, 3, v4ent)) != MG_OK)
917     return(rv);
918     if ((rv = mg_handle(MG_E_POINT, 4, p4ent)) != MG_OK)
919     return(rv);
920     if ((rv = mg_handle(MG_E_NORMAL, 4, n4ent)) != MG_OK)
921     return(rv);
922     for (i = 1; i <= 4*mg_nqcdivs; i++) {
923     theta = sgn*i*(PI/2)/mg_nqcdivs;
924     if ((rv = mg_handle(MG_E_VERTEX, 4, v1ent)) != MG_OK)
925     return(rv);
926     if ((rv = mg_handle(MG_E_VERTEX, 4, v2ent)) != MG_OK)
927     return(rv);
928     for (j = 0; j < 3; j++) {
929     d = u[j]*cos(theta) + v[j]*sin(theta);
930     sprintf(p3[j], FLTFMT, cv2->p[j] + rad2*d);
931     if (n2off > -FHUGE)
932     sprintf(n3[j], FLTFMT, d + w[j]*n2off);
933     sprintf(p4[j], FLTFMT, cv1->p[j] + rad1*d);
934     if (n1off < FHUGE)
935     sprintf(n4[j], FLTFMT, d + w[j]*n1off);
936     }
937     if ((rv = mg_handle(MG_E_VERTEX, 2, v3ent)) != MG_OK)
938     return(rv);
939     if ((rv = mg_handle(MG_E_POINT, 4, p3ent)) != MG_OK)
940     return(rv);
941     if (n2off > -FHUGE &&
942     (rv = mg_handle(MG_E_NORMAL, 4, n3ent)) != MG_OK)
943     return(rv);
944     if ((rv = mg_handle(MG_E_VERTEX, 2, v4ent)) != MG_OK)
945     return(rv);
946     if ((rv = mg_handle(MG_E_POINT, 4, p4ent)) != MG_OK)
947     return(rv);
948     if (n1off < FHUGE &&
949     (rv = mg_handle(MG_E_NORMAL, 4, n4ent)) != MG_OK)
950     return(rv);
951     if ((rv = mg_handle(MG_E_FACE, 5, fent)) != MG_OK)
952     return(rv);
953     }
954     }
955     return(MG_OK);
956     }
957    
958    
959     int
960     e_prism( /* turn a prism into polygons */
961     int ac,
962     char **av
963     )
964     {
965     static char p[3][24];
966     static char *vent[5] = {mg_ename[MG_E_VERTEX],NULL,"="};
967     static char *pent[5] = {mg_ename[MG_E_POINT],p[0],p[1],p[2]};
968     static char *znorm[5] = {mg_ename[MG_E_NORMAL],"0","0","0"};
969     char *newav[MG_MAXARGC], nvn[MG_MAXARGC-1][8];
970     double length;
971     int hasnorm;
972     FVECT v1, v2, v3, norm;
973     register C_VERTEX *cv;
974     C_VERTEX *cv0;
975     int rv;
976     register int i, j;
977     /* check arguments */
978     if (ac < 5)
979     return(MG_EARGC);
980     if (!isflt(av[ac-1]))
981     return(MG_ETYPE);
982     length = atof(av[ac-1]);
983     if (length <= FTINY && length >= -FTINY)
984     return(MG_EILL);
985     /* compute face normal */
986     if ((cv0 = c_getvert(av[1])) == NULL)
987     return(MG_EUNDEF);
988     hasnorm = 0;
989     norm[0] = norm[1] = norm[2] = 0.;
990     v1[0] = v1[1] = v1[2] = 0.;
991     for (i = 2; i < ac-1; i++) {
992     if ((cv = c_getvert(av[i])) == NULL)
993     return(MG_EUNDEF);
994     hasnorm += !is0vect(cv->n);
995     v2[0] = cv->p[0] - cv0->p[0];
996     v2[1] = cv->p[1] - cv0->p[1];
997     v2[2] = cv->p[2] - cv0->p[2];
998     fcross(v3, v1, v2);
999     norm[0] += v3[0];
1000     norm[1] += v3[1];
1001     norm[2] += v3[2];
1002     VCOPY(v1, v2);
1003     }
1004     if (normalize(norm) == 0.)
1005     return(MG_EILL);
1006     /* create moved vertices */
1007     for (i = 1; i < ac-1; i++) {
1008     sprintf(nvn[i-1], "_pv%d", i);
1009     vent[1] = nvn[i-1];
1010     vent[3] = av[i];
1011     if ((rv = mg_handle(MG_E_VERTEX, 4, vent)) != MG_OK)
1012     return(rv);
1013     cv = c_getvert(av[i]); /* checked above */
1014     for (j = 0; j < 3; j++)
1015     sprintf(p[j], FLTFMT, cv->p[j] - length*norm[j]);
1016     if ((rv = mg_handle(MG_E_POINT, 4, pent)) != MG_OK)
1017     return(rv);
1018     }
1019     /* make faces */
1020     newav[0] = mg_ename[MG_E_FACE];
1021     /* do the side faces */
1022     newav[5] = NULL;
1023     newav[3] = av[ac-2];
1024     newav[4] = nvn[ac-3];
1025     for (i = 1; i < ac-1; i++) {
1026     newav[1] = nvn[i-1];
1027     newav[2] = av[i];
1028     if ((rv = mg_handle(MG_E_FACE, 5, newav)) != MG_OK)
1029     return(rv);
1030     newav[3] = newav[2];
1031     newav[4] = newav[1];
1032     }
1033     /* do top face */
1034     for (i = 1; i < ac-1; i++) {
1035     if (hasnorm) { /* zero normals */
1036     vent[1] = nvn[i-1];
1037     if ((rv = mg_handle(MG_E_VERTEX, 2, vent)) != MG_OK)
1038     return(rv);
1039     if ((rv = mg_handle(MG_E_NORMAL, 4, znorm)) != MG_OK)
1040     return(rv);
1041     }
1042     newav[ac-1-i] = nvn[i-1]; /* reverse */
1043     }
1044     if ((rv = mg_handle(MG_E_FACE, ac-1, newav)) != MG_OK)
1045     return(rv);
1046     /* do bottom face */
1047     if (hasnorm)
1048     for (i = 1; i < ac-1; i++) {
1049     vent[1] = nvn[i-1];
1050     vent[3] = av[i];
1051     if ((rv = mg_handle(MG_E_VERTEX, 4, vent)) != MG_OK)
1052     return(rv);
1053     if ((rv = mg_handle(MG_E_NORMAL, 4, znorm)) != MG_OK)
1054     return(rv);
1055     newav[i] = nvn[i-1];
1056     }
1057     else
1058     for (i = 1; i < ac-1; i++)
1059     newav[i] = av[i];
1060     newav[i] = NULL;
1061     if ((rv = mg_handle(MG_E_FACE, i, newav)) != MG_OK)
1062     return(rv);
1063     return(MG_OK);
1064     }
1065    
1066    
1067     static int
1068     put_cxy(void) /* put out current xy chromaticities */
1069     {
1070     static char xbuf[24], ybuf[24];
1071     static char *ccom[4] = {mg_ename[MG_E_CXY], xbuf, ybuf};
1072    
1073     sprintf(xbuf, "%.4f", c_ccolor->cx);
1074     sprintf(ybuf, "%.4f", c_ccolor->cy);
1075     return(mg_handle(MG_E_CXY, 3, ccom));
1076     }
1077    
1078    
1079     static int
1080     put_cspec(void) /* put out current color spectrum */
1081     {
1082     char wl[2][6], vbuf[C_CNSS][24];
1083     char *newav[C_CNSS+4];
1084     double sf;
1085     register int i;
1086    
1087     if (mg_ehand[MG_E_CSPEC] != c_hcolor) {
1088     sprintf(wl[0], "%d", C_CMINWL);
1089     sprintf(wl[1], "%d", C_CMAXWL);
1090     newav[0] = mg_ename[MG_E_CSPEC];
1091     newav[1] = wl[0];
1092     newav[2] = wl[1];
1093     sf = (double)C_CNSS / c_ccolor->ssum;
1094     for (i = 0; i < C_CNSS; i++) {
1095     sprintf(vbuf[i], "%.4f", sf*c_ccolor->ssamp[i]);
1096     newav[i+3] = vbuf[i];
1097     }
1098     newav[C_CNSS+3] = NULL;
1099     if ((i = mg_handle(MG_E_CSPEC, C_CNSS+3, newav)) != MG_OK)
1100     return(i);
1101     }
1102     return(MG_OK);
1103     }
1104    
1105    
1106     static int
1107     e_cspec( /* handle spectral color */
1108     int ac,
1109     char **av
1110     )
1111     {
1112     /* convert to xy chromaticity */
1113     c_ccvt(c_ccolor, C_CSXY);
1114     /* if it's really their handler, use it */
1115     if (mg_ehand[MG_E_CXY] != c_hcolor)
1116     return(put_cxy());
1117     return(MG_OK);
1118     }
1119    
1120    
1121     static int
1122     e_cmix( /* handle mixing of colors */
1123     int ac,
1124     char **av
1125     )
1126     {
1127     /*
1128     * Contorted logic works as follows:
1129     * 1. the colors are already mixed in c_hcolor() support function
1130     * 2. if we would handle a spectral result, make sure it's not
1131     * 3. if c_hcolor() would handle a spectral result, don't bother
1132     * 4. otherwise, make cspec entity and pass it to their handler
1133     * 5. if we have only xy results, handle it as c_spec() would
1134     */
1135     if (mg_ehand[MG_E_CSPEC] == e_cspec)
1136     c_ccvt(c_ccolor, C_CSXY);
1137     else if (c_ccolor->flags & C_CDSPEC)
1138     return(put_cspec());
1139     if (mg_ehand[MG_E_CXY] != c_hcolor)
1140     return(put_cxy());
1141     return(MG_OK);
1142     }
1143    
1144    
1145     static int
1146     e_cct( /* handle color temperature */
1147     int ac,
1148     char **av
1149     )
1150     {
1151     /*
1152     * Logic is similar to e_cmix here. Support handler has already
1153     * converted temperature to spectral color. Put it out as such
1154     * if they support it, otherwise convert to xy chromaticity and
1155     * put it out if they handle it.
1156     */
1157     if (mg_ehand[MG_E_CSPEC] != e_cspec)
1158     return(put_cspec());
1159     c_ccvt(c_ccolor, C_CSXY);
1160     if (mg_ehand[MG_E_CXY] != c_hcolor)
1161     return(put_cxy());
1162     return(MG_OK);
1163     }