| 1 | greg | 1.1 | #ifndef lint | 
| 2 | greg | 2.40 | static const char       RCSid[] = "$Id: func.c,v 2.39 2022/03/30 16:00:56 greg Exp $"; | 
| 3 | greg | 1.1 | #endif | 
| 4 |  |  | /* | 
| 5 |  |  | *  func.c - interface to calcomp functions. | 
| 6 | greg | 2.14 | */ | 
| 7 |  |  |  | 
| 8 | greg | 2.15 | #include "copyright.h" | 
| 9 | greg | 1.1 |  | 
| 10 |  |  | #include  "ray.h" | 
| 11 | greg | 2.21 | #include  "paths.h" | 
| 12 | greg | 1.1 | #include  "otypes.h" | 
| 13 | greg | 2.2 | #include  "func.h" | 
| 14 | greg | 2.30 | #include <ctype.h> | 
| 15 | greg | 1.1 |  | 
| 16 | greg | 2.2 |  | 
| 17 | greg | 1.21 | #define  INITFILE       "rayinit.cal" | 
| 18 | greg | 2.2 | #define  CALSUF         ".cal" | 
| 19 |  |  | #define  LCALSUF        4 | 
| 20 | greg | 2.10 | char  REFVNAME[] = "`FILE_REFCNT"; | 
| 21 | greg | 1.21 |  | 
| 22 | greg | 1.13 | XF  unitxf = {                  /* identity transform */ | 
| 23 | greg | 2.8 | {{1.0, 0.0, 0.0, 0.0}, | 
| 24 |  |  | {0.0, 1.0, 0.0, 0.0}, | 
| 25 |  |  | {0.0, 0.0, 1.0, 0.0}, | 
| 26 |  |  | {0.0, 0.0, 0.0, 1.0}}, | 
| 27 | greg | 1.13 | 1.0 | 
| 28 |  |  | }; | 
| 29 |  |  |  | 
| 30 | greg | 1.12 | XF  funcxf;                     /* current transformation */ | 
| 31 |  |  | static OBJREC  *fobj = NULL;    /* current function object */ | 
| 32 |  |  | static RAY  *fray = NULL;       /* current function ray */ | 
| 33 | greg | 1.1 |  | 
| 34 | greg | 2.26 | static char  rayinitcal[] = INITFILE; | 
| 35 |  |  |  | 
| 36 | greg | 2.20 | static double  l_erf(char *), l_erfc(char *), l_arg(char *); | 
| 37 | greg | 1.1 |  | 
| 38 | greg | 2.2 |  | 
| 39 | greg | 2.26 | void | 
| 40 | greg | 2.32 | initfunc(void)  /* initialize function evaluation */ | 
| 41 | greg | 2.26 | { | 
| 42 |  |  | if (!rayinitcal[0])     /* already done? */ | 
| 43 |  |  | return; | 
| 44 |  |  | esupport |= E_VARIABLE|E_FUNCTION|E_INCHAN|E_RCONST|E_REDEFW; | 
| 45 |  |  | esupport &= ~(E_OUTCHAN); | 
| 46 | greg | 2.39 | calcontext(""); | 
| 47 | greg | 2.26 | scompile("Dx=$1;Dy=$2;Dz=$3;", NULL, 0); | 
| 48 |  |  | scompile("Nx=$4;Ny=$5;Nz=$6;", NULL, 0); | 
| 49 |  |  | scompile("Px=$7;Py=$8;Pz=$9;", NULL, 0); | 
| 50 |  |  | scompile("T=$10;Ts=$25;Rdot=$11;", NULL, 0); | 
| 51 |  |  | scompile("S=$12;Tx=$13;Ty=$14;Tz=$15;", NULL, 0); | 
| 52 |  |  | scompile("Ix=$16;Iy=$17;Iz=$18;", NULL, 0); | 
| 53 |  |  | scompile("Jx=$19;Jy=$20;Jz=$21;", NULL, 0); | 
| 54 |  |  | scompile("Kx=$22;Ky=$23;Kz=$24;", NULL, 0); | 
| 55 |  |  | scompile("Lu=$26;Lv=$27;", NULL, 0); | 
| 56 |  |  | funset("arg", 1, '=', l_arg); | 
| 57 |  |  | funset("erf", 1, ':', l_erf); | 
| 58 |  |  | funset("erfc", 1, ':', l_erfc); | 
| 59 |  |  | setnoisefuncs(); | 
| 60 |  |  | setprismfuncs(); | 
| 61 |  |  | loadfunc(rayinitcal); | 
| 62 |  |  | rayinitcal[0] = '\0'; | 
| 63 |  |  | } | 
| 64 |  |  |  | 
| 65 |  |  |  | 
| 66 | greg | 2.29 | /* Set parameters for current evaluation */ | 
| 67 |  |  | void | 
| 68 |  |  | set_eparams(char *prms) | 
| 69 |  |  | { | 
| 70 | greg | 2.35 | static char     *last_params = NULL; | 
| 71 | greg | 2.29 | char            vname[RMAXWORD]; | 
| 72 |  |  | double          value; | 
| 73 |  |  | char            *cpd; | 
| 74 |  |  | /* check if already set */ | 
| 75 | greg | 2.32 | if (prms == NULL || !*prms) | 
| 76 | greg | 2.29 | return; | 
| 77 | greg | 2.35 | if (prms == last_params || (last_params != NULL && | 
| 78 |  |  | !strcmp(prms, last_params))) | 
| 79 | greg | 2.29 | return; | 
| 80 | greg | 2.35 | last_params = prms;             /* XXX assumes static string */ | 
| 81 | greg | 2.32 | /* assign each variable */ | 
| 82 | greg | 2.29 | while (*prms) { | 
| 83 |  |  | if (isspace(*prms)) { | 
| 84 |  |  | ++prms; continue; | 
| 85 |  |  | } | 
| 86 |  |  | if (!isalpha(*prms)) | 
| 87 |  |  | goto bad_params; | 
| 88 |  |  | cpd = vname; | 
| 89 |  |  | while (*prms && (*prms != '=') & !isspace(*prms)) { | 
| 90 | greg | 2.31 | if (!isid(*prms) | (cpd-vname >= RMAXWORD-1)) | 
| 91 | greg | 2.29 | goto bad_params; | 
| 92 |  |  | *cpd++ = *prms++; | 
| 93 |  |  | } | 
| 94 |  |  | *cpd = '\0'; | 
| 95 |  |  | while (isspace(*prms)) prms++; | 
| 96 |  |  | if (*prms++ != '=') | 
| 97 |  |  | goto bad_params; | 
| 98 |  |  | value = atof(prms); | 
| 99 |  |  | if ((prms = fskip(prms)) == NULL) | 
| 100 |  |  | goto bad_params; | 
| 101 |  |  | while (isspace(*prms)) prms++; | 
| 102 | greg | 2.37 | prms += (*prms == ',') | (*prms == ';') | (*prms == ':'); | 
| 103 | greg | 2.29 | varset(vname, '=', value); | 
| 104 |  |  | } | 
| 105 | greg | 2.34 | eclock++;               /* notify expression evaluator */ | 
| 106 | greg | 2.29 | return; | 
| 107 |  |  | bad_params: | 
| 108 |  |  | sprintf(errmsg, "bad parameter list '%s'", last_params); | 
| 109 |  |  | error(USER, errmsg); | 
| 110 |  |  | } | 
| 111 |  |  |  | 
| 112 |  |  |  | 
| 113 | greg | 2.25 | MFUNC * | 
| 114 | schorsch | 2.22 | getfunc(        /* get function for this modifier */ | 
| 115 |  |  | OBJREC  *m, | 
| 116 |  |  | int  ff, | 
| 117 |  |  | unsigned int  ef, | 
| 118 |  |  | int  dofwd | 
| 119 |  |  | ) | 
| 120 | greg | 2.2 | { | 
| 121 |  |  | char  sbuf[MAXSTR]; | 
| 122 | greg | 2.25 | char  **arg; | 
| 123 |  |  | MFUNC  *f; | 
| 124 | greg | 2.2 | int  ne, na; | 
| 125 | greg | 2.25 | int  i; | 
| 126 | greg | 2.2 | /* check to see if done already */ | 
| 127 |  |  | if ((f = (MFUNC *)m->os) != NULL) | 
| 128 |  |  | return(f); | 
| 129 | greg | 2.7 | fobj = NULL; fray = NULL; | 
| 130 | greg | 2.26 | if (rayinitcal[0])              /* initialize on first call */ | 
| 131 |  |  | initfunc(); | 
| 132 | greg | 2.2 | if ((na = m->oargs.nsargs) <= ff) | 
| 133 |  |  | goto toofew; | 
| 134 |  |  | arg = m->oargs.sarg; | 
| 135 |  |  | if ((f = (MFUNC *)calloc(1, sizeof(MFUNC))) == NULL) | 
| 136 |  |  | goto memerr; | 
| 137 |  |  | i = strlen(arg[ff]);                    /* set up context */ | 
| 138 | greg | 2.26 | if (i == 1 && arg[ff][0] == '.') { | 
| 139 | greg | 2.39 | calcontext(f->ctx = "");        /* "." means no file */ | 
| 140 | greg | 2.26 | } else { | 
| 141 | greg | 2.14 | strcpy(sbuf,arg[ff]);           /* file name is context */ | 
| 142 | greg | 2.2 | if (i > LCALSUF && !strcmp(sbuf+i-LCALSUF, CALSUF)) | 
| 143 |  |  | sbuf[i-LCALSUF] = '\0'; /* remove suffix */ | 
| 144 | greg | 2.39 | calcontext(f->ctx = savestr(sbuf)); | 
| 145 | greg | 2.2 | if (!vardefined(REFVNAME)) {    /* file loaded? */ | 
| 146 | greg | 2.5 | loadfunc(arg[ff]); | 
| 147 | greg | 2.2 | varset(REFVNAME, '=', 1.0); | 
| 148 |  |  | } else                          /* reference_count++ */ | 
| 149 |  |  | varset(REFVNAME, '=', varvalue(REFVNAME)+1.0); | 
| 150 |  |  | } | 
| 151 |  |  | curfunc = NULL;                 /* parse expressions */ | 
| 152 |  |  | sprintf(sbuf, "%s \"%s\"", ofun[m->otype].funame, m->oname); | 
| 153 |  |  | for (i=0, ne=0; ef && i < na; i++, ef>>=1) | 
| 154 |  |  | if (ef & 1) {                   /* flagged as an expression? */ | 
| 155 |  |  | if (ne >= MAXEXPR) | 
| 156 |  |  | objerror(m, INTERNAL, "too many expressions"); | 
| 157 |  |  | initstr(arg[i], sbuf, 0); | 
| 158 |  |  | f->ep[ne++] = getE1(); | 
| 159 |  |  | if (nextc != EOF) | 
| 160 |  |  | syntax("unexpected character"); | 
| 161 |  |  | } | 
| 162 |  |  | if (ef) | 
| 163 |  |  | goto toofew; | 
| 164 |  |  | if (i <= ff)                    /* find transform args */ | 
| 165 |  |  | i = ff+1; | 
| 166 |  |  | while (i < na && arg[i][0] != '-') | 
| 167 |  |  | i++; | 
| 168 | greg | 2.26 | if (i == na) {                  /* no transform */ | 
| 169 |  |  | f->fxp = f->bxp = &unitxf; | 
| 170 |  |  | } else {                        /* get transform */ | 
| 171 |  |  | if ((f->bxp = (XF *)malloc(sizeof(XF))) == NULL) | 
| 172 | greg | 2.3 | goto memerr; | 
| 173 | greg | 2.26 | if (invxf(f->bxp, na-i, arg+i) != na-i) | 
| 174 | greg | 2.2 | objerror(m, USER, "bad transform"); | 
| 175 | greg | 2.26 | if (f->bxp->sca < 0.0) | 
| 176 |  |  | f->bxp->sca = -f->bxp->sca; | 
| 177 | greg | 2.2 | if (dofwd) {                    /* do both transforms */ | 
| 178 | greg | 2.26 | if ((f->fxp = (XF *)malloc(sizeof(XF))) == NULL) | 
| 179 | greg | 2.3 | goto memerr; | 
| 180 | greg | 2.26 | xf(f->fxp, na-i, arg+i); | 
| 181 |  |  | if (f->fxp->sca < 0.0) | 
| 182 |  |  | f->fxp->sca = -f->fxp->sca; | 
| 183 | greg | 2.2 | } | 
| 184 |  |  | } | 
| 185 |  |  | m->os = (char *)f; | 
| 186 |  |  | return(f); | 
| 187 |  |  | toofew: | 
| 188 | greg | 2.4 | objerror(m, USER, "too few string arguments"); | 
| 189 | greg | 2.2 | memerr: | 
| 190 |  |  | error(SYSTEM, "out of memory in getfunc"); | 
| 191 | schorsch | 2.22 | return NULL; /* pro forma return */ | 
| 192 | greg | 2.2 | } | 
| 193 |  |  |  | 
| 194 |  |  |  | 
| 195 | greg | 2.25 | void | 
| 196 | schorsch | 2.22 | freefunc(                       /* free memory associated with modifier */ | 
| 197 |  |  | OBJREC  *m | 
| 198 |  |  | ) | 
| 199 | greg | 2.2 | { | 
| 200 | greg | 2.25 | MFUNC  *f; | 
| 201 |  |  | int  i; | 
| 202 | greg | 2.2 |  | 
| 203 |  |  | if ((f = (MFUNC *)m->os) == NULL) | 
| 204 |  |  | return; | 
| 205 |  |  | for (i = 0; f->ep[i] != NULL; i++) | 
| 206 | greg | 2.40 | epfree(f->ep[i],1); | 
| 207 | greg | 2.2 | if (f->ctx[0]) {                        /* done with definitions */ | 
| 208 | greg | 2.39 | calcontext(f->ctx); | 
| 209 | greg | 2.2 | i = varvalue(REFVNAME)-.5;      /* reference_count-- */ | 
| 210 |  |  | if (i > 0) | 
| 211 |  |  | varset(REFVNAME, '=', (double)i); | 
| 212 |  |  | else | 
| 213 |  |  | dcleanup(2);            /* remove definitions */ | 
| 214 |  |  | freestr(f->ctx); | 
| 215 |  |  | } | 
| 216 | greg | 2.26 | if (f->bxp != &unitxf) | 
| 217 |  |  | free((void *)f->bxp); | 
| 218 |  |  | if ((f->fxp != NULL) & (f->fxp != &unitxf)) | 
| 219 |  |  | free((void *)f->fxp); | 
| 220 | greg | 2.14 | free((void *)f); | 
| 221 | greg | 2.2 | m->os = NULL; | 
| 222 |  |  | } | 
| 223 |  |  |  | 
| 224 |  |  |  | 
| 225 | greg | 2.25 | int | 
| 226 | schorsch | 2.22 | setfunc(                        /* set channels for function call */ | 
| 227 | greg | 2.26 | OBJREC  *m, | 
| 228 |  |  | RAY     *r | 
| 229 | schorsch | 2.22 | ) | 
| 230 | greg | 1.1 | { | 
| 231 | greg | 2.26 | static RNUMBER  lastrno = ~0; | 
| 232 |  |  | MFUNC           *f; | 
| 233 | greg | 2.25 | /* get function if any */ | 
| 234 | greg | 2.26 | if ((f = (MFUNC *)m->os) == NULL) | 
| 235 |  |  | objerror(m, CONSISTENCY, "setfunc called before getfunc"); | 
| 236 |  |  |  | 
| 237 | greg | 2.39 | calcontext(f->ctx);             /* set evaluator context */ | 
| 238 | greg | 2.2 | /* check to see if matrix set */ | 
| 239 | greg | 2.25 | if ((m == fobj) & (r->rno == lastrno)) | 
| 240 | greg | 1.17 | return(0); | 
| 241 | greg | 1.1 | fobj = m; | 
| 242 |  |  | fray = r; | 
| 243 | greg | 2.26 | if (r->rox != NULL) { | 
| 244 |  |  | if (f->bxp != &unitxf) { | 
| 245 |  |  | funcxf.sca = r->rox->b.sca * f->bxp->sca; | 
| 246 |  |  | multmat4(funcxf.xfm, r->rox->b.xfm, f->bxp->xfm); | 
| 247 | greg | 1.13 | } else | 
| 248 | schorsch | 2.19 | funcxf = r->rox->b; | 
| 249 | greg | 2.26 | } else | 
| 250 |  |  | funcxf = *f->bxp; | 
| 251 |  |  | lastrno = r->rno; | 
| 252 |  |  | eclock++;               /* notify expression evaluator */ | 
| 253 |  |  | return(1); | 
| 254 |  |  | } | 
| 255 |  |  |  | 
| 256 |  |  |  | 
| 257 |  |  | int | 
| 258 |  |  | worldfunc(                      /* special function context sans object */ | 
| 259 |  |  | char    *ctx, | 
| 260 |  |  | RAY     *r | 
| 261 |  |  | ) | 
| 262 |  |  | { | 
| 263 |  |  | static RNUMBER  lastrno = ~0; | 
| 264 | greg | 2.27 |  | 
| 265 |  |  | if (rayinitcal[0])              /* initialize on first call */ | 
| 266 |  |  | initfunc(); | 
| 267 | greg | 2.26 | /* set evaluator context */ | 
| 268 | greg | 2.39 | calcontext(ctx); | 
| 269 | greg | 2.26 | /* check if ray already set */ | 
| 270 |  |  | if ((fobj == NULL) & (r->rno == lastrno)) | 
| 271 |  |  | return(0); | 
| 272 |  |  | fobj = NULL; | 
| 273 |  |  | fray = r; | 
| 274 |  |  | funcxf = unitxf; | 
| 275 | greg | 1.16 | lastrno = r->rno; | 
| 276 | greg | 1.1 | eclock++;               /* notify expression evaluator */ | 
| 277 | greg | 1.17 | return(1); | 
| 278 | greg | 1.1 | } | 
| 279 |  |  |  | 
| 280 |  |  |  | 
| 281 | greg | 2.25 | void | 
| 282 | schorsch | 2.22 | loadfunc(                       /* load definition file */ | 
| 283 |  |  | char  *fname | 
| 284 |  |  | ) | 
| 285 | greg | 1.1 | { | 
| 286 |  |  | char  *ffname; | 
| 287 |  |  |  | 
| 288 | greg | 2.18 | if ((ffname = getpath(fname, getrlibpath(), R_OK)) == NULL) { | 
| 289 | greg | 1.1 | sprintf(errmsg, "cannot find function file \"%s\"", fname); | 
| 290 | greg | 2.31 | error(SYSTEM, errmsg); | 
| 291 | greg | 1.1 | } | 
| 292 |  |  | fcompile(ffname); | 
| 293 | greg | 2.40 | doptimize(1);           /* optimize definitions */ | 
| 294 | greg | 1.1 | } | 
| 295 |  |  |  | 
| 296 |  |  |  | 
| 297 | greg | 2.2 | static double | 
| 298 | greg | 2.20 | l_arg(char *nm)                 /* return nth real argument */ | 
| 299 | greg | 1.1 | { | 
| 300 | greg | 2.25 | int  n; | 
| 301 | greg | 1.1 |  | 
| 302 | greg | 2.7 | if (fobj == NULL) | 
| 303 | greg | 2.38 | error(USER, | 
| 304 |  |  | "bad call to arg(n) - illegal constant in .cal file?"); | 
| 305 | greg | 2.7 |  | 
| 306 | greg | 1.1 | n = argument(1) + .5;           /* round to integer */ | 
| 307 |  |  |  | 
| 308 |  |  | if (n < 1) | 
| 309 |  |  | return(fobj->oargs.nfargs); | 
| 310 |  |  |  | 
| 311 |  |  | if (n > fobj->oargs.nfargs) { | 
| 312 |  |  | sprintf(errmsg, "missing real argument %d", n); | 
| 313 |  |  | objerror(fobj, USER, errmsg); | 
| 314 |  |  | } | 
| 315 |  |  | return(fobj->oargs.farg[n-1]); | 
| 316 | greg | 1.19 | } | 
| 317 |  |  |  | 
| 318 |  |  |  | 
| 319 | greg | 2.2 | static double | 
| 320 | greg | 2.20 | l_erf(char *nm)                 /* error function */ | 
| 321 | greg | 1.19 | { | 
| 322 |  |  | return(erf(argument(1))); | 
| 323 |  |  | } | 
| 324 |  |  |  | 
| 325 |  |  |  | 
| 326 | greg | 2.2 | static double | 
| 327 | greg | 2.20 | l_erfc(char *nm)                /* cumulative error function */ | 
| 328 | greg | 1.19 | { | 
| 329 |  |  | return(erfc(argument(1))); | 
| 330 | greg | 1.1 | } | 
| 331 |  |  |  | 
| 332 |  |  |  | 
| 333 | greg | 2.25 | double | 
| 334 | schorsch | 2.22 | chanvalue(                      /* return channel n to calcomp */ | 
| 335 | greg | 2.25 | int  n | 
| 336 | schorsch | 2.22 | ) | 
| 337 | greg | 1.1 | { | 
| 338 | greg | 2.7 | if (fray == NULL) | 
| 339 |  |  | syntax("ray parameter used in constant expression"); | 
| 340 | greg | 1.1 |  | 
| 341 | greg | 1.10 | if (--n < 0) | 
| 342 |  |  | goto badchan; | 
| 343 | greg | 1.1 |  | 
| 344 | greg | 2.17 | if (n <= 2)                     /* ray direction */ | 
| 345 | greg | 1.1 |  | 
| 346 | greg | 1.12 | return( (       fray->rdir[0]*funcxf.xfm[0][n] + | 
| 347 |  |  | fray->rdir[1]*funcxf.xfm[1][n] + | 
| 348 |  |  | fray->rdir[2]*funcxf.xfm[2][n]  ) | 
| 349 |  |  | / funcxf.sca ); | 
| 350 | greg | 1.1 |  | 
| 351 | greg | 2.17 | if (n <= 5)                     /* surface normal */ | 
| 352 | greg | 1.8 |  | 
| 353 | greg | 1.12 | return( (       fray->ron[0]*funcxf.xfm[0][n-3] + | 
| 354 |  |  | fray->ron[1]*funcxf.xfm[1][n-3] + | 
| 355 |  |  | fray->ron[2]*funcxf.xfm[2][n-3] ) | 
| 356 |  |  | / funcxf.sca ); | 
| 357 | greg | 1.8 |  | 
| 358 | greg | 2.28 | if (n <= 8) {                   /* intersection point */ | 
| 359 | greg | 2.36 | if (fray->rot >= FHUGE*.99) | 
| 360 | greg | 2.28 | return(0.0);    /* XXX should be runtime error? */ | 
| 361 | greg | 1.8 |  | 
| 362 | greg | 1.12 | return( fray->rop[0]*funcxf.xfm[0][n-6] + | 
| 363 |  |  | fray->rop[1]*funcxf.xfm[1][n-6] + | 
| 364 |  |  | fray->rop[2]*funcxf.xfm[2][n-6] + | 
| 365 |  |  | funcxf.xfm[3][n-6] ); | 
| 366 | greg | 2.28 | } | 
| 367 | greg | 1.8 |  | 
| 368 | greg | 2.13 | if (n == 9)                     /* total distance */ | 
| 369 |  |  | return(raydist(fray,PRIMARY) * funcxf.sca); | 
| 370 | greg | 1.10 |  | 
| 371 | greg | 1.18 | if (n == 10)                    /* dot product (range [-1,1]) */ | 
| 372 |  |  | return( fray->rod <= -1.0 ? -1.0 : | 
| 373 |  |  | fray->rod >= 1.0 ? 1.0 : | 
| 374 |  |  | fray->rod ); | 
| 375 | greg | 1.10 |  | 
| 376 | greg | 1.8 | if (n == 11)                    /* scale */ | 
| 377 | greg | 1.12 | return(funcxf.sca); | 
| 378 | greg | 1.8 |  | 
| 379 | greg | 2.17 | if (n <= 14)                    /* origin */ | 
| 380 | greg | 1.12 | return(funcxf.xfm[3][n-12]); | 
| 381 | greg | 1.8 |  | 
| 382 | greg | 2.17 | if (n <= 17)                    /* i unit vector */ | 
| 383 | greg | 1.12 | return(funcxf.xfm[0][n-15] / funcxf.sca); | 
| 384 | greg | 1.8 |  | 
| 385 | greg | 2.17 | if (n <= 20)                    /* j unit vector */ | 
| 386 |  |  | return(funcxf.xfm[1][n-18] / funcxf.sca); | 
| 387 | greg | 1.8 |  | 
| 388 | greg | 2.17 | if (n <= 23)                    /* k unit vector */ | 
| 389 | greg | 1.12 | return(funcxf.xfm[2][n-21] / funcxf.sca); | 
| 390 | greg | 2.6 |  | 
| 391 | greg | 2.17 | if (n == 24)                    /* single ray (shadow) distance */ | 
| 392 | greg | 2.13 | return((fray->rot+raydist(fray->parent,SHADOW)) * funcxf.sca); | 
| 393 | greg | 2.16 |  | 
| 394 | greg | 2.17 | if (n <= 26)                    /* local (u,v) coordinates */ | 
| 395 |  |  | return(fray->uv[n-25]); | 
| 396 | greg | 1.10 | badchan: | 
| 397 |  |  | error(USER, "illegal channel number"); | 
| 398 | greg | 2.16 | return(0.0); | 
| 399 | greg | 1.1 | } |