| 1 | #ifndef lint | 
| 2 | static const char RCSid[] = "$Id: bsdf2ttree.c,v 2.27 2014/03/12 22:24:59 greg Exp $"; | 
| 3 | #endif | 
| 4 | /* | 
| 5 | * Load measured BSDF interpolant and write out as XML file with tensor tree. | 
| 6 | * | 
| 7 | *      G. Ward | 
| 8 | */ | 
| 9 |  | 
| 10 | #define _USE_MATH_DEFINES | 
| 11 | #include <stdio.h> | 
| 12 | #include <stdlib.h> | 
| 13 | #include <math.h> | 
| 14 | #include "random.h" | 
| 15 | #include "platform.h" | 
| 16 | #include "rtprocess.h" | 
| 17 | #include "calcomp.h" | 
| 18 | #include "bsdfrep.h" | 
| 19 | /* global argv[0] */ | 
| 20 | char                    *progname; | 
| 21 | /* percentage to cull (<0 to turn off) */ | 
| 22 | double                  pctcull = 90.; | 
| 23 | /* sampling order */ | 
| 24 | int                     samp_order = 6; | 
| 25 | /* super-sampling threshold */ | 
| 26 | const double            ssamp_thresh = 0.35; | 
| 27 | /* number of super-samples */ | 
| 28 | #ifndef NSSAMP | 
| 29 | #define NSSAMP          100 | 
| 30 | #endif | 
| 31 | /* limit on number of RBF lobes */ | 
| 32 | static int              lobe_lim = 15000; | 
| 33 | /* progress bar length */ | 
| 34 | static int              do_prog = 79; | 
| 35 |  | 
| 36 |  | 
| 37 | /* Start new progress bar */ | 
| 38 | #define prog_start(s)   if (do_prog) fprintf(stderr, "%s: %s...\n", progname, s); else | 
| 39 |  | 
| 40 | /* Draw progress bar of the appropriate length */ | 
| 41 | static void | 
| 42 | prog_show(double frac) | 
| 43 | { | 
| 44 | char    pbar[256]; | 
| 45 | int     nchars; | 
| 46 |  | 
| 47 | if (do_prog <= 0) return; | 
| 48 | if (do_prog > sizeof(pbar)-2) | 
| 49 | do_prog = sizeof(pbar)-2; | 
| 50 | if (frac < 0) frac = 0; | 
| 51 | else if (frac > 1) frac = 1; | 
| 52 | nchars = do_prog*frac + .5; | 
| 53 | pbar[0] = '\r'; | 
| 54 | memset(pbar+1, '*', nchars); | 
| 55 | memset(pbar+1+nchars, '-', do_prog-nchars); | 
| 56 | pbar[do_prog+1] = '\0'; | 
| 57 | fputs(pbar, stderr); | 
| 58 | } | 
| 59 |  | 
| 60 | /* Finish progress bar */ | 
| 61 | static void | 
| 62 | prog_done(void) | 
| 63 | { | 
| 64 | int     n = do_prog; | 
| 65 |  | 
| 66 | if (n <= 1) return; | 
| 67 | fputc('\r', stderr); | 
| 68 | while (n--) | 
| 69 | fputc(' ', stderr); | 
| 70 | fputc('\r', stderr); | 
| 71 | } | 
| 72 |  | 
| 73 | /* Output XML prologue to stdout */ | 
| 74 | static void | 
| 75 | xml_prologue(int ac, char *av[]) | 
| 76 | { | 
| 77 | puts("<?xml version=\"1.0\" encoding=\"UTF-8\"?>"); | 
| 78 | puts("<WindowElement xmlns=\"http://windows.lbl.gov\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:schemaLocation=\"http://windows.lbl.gov/BSDF-v1.4.xsd\">"); | 
| 79 | fputs("<!-- File produced by:", stdout); | 
| 80 | while (ac-- > 0) { | 
| 81 | fputc(' ', stdout); | 
| 82 | fputs(*av++, stdout); | 
| 83 | } | 
| 84 | puts(" -->"); | 
| 85 | puts("<WindowElementType>System</WindowElementType>"); | 
| 86 | puts("<FileType>BSDF</FileType>"); | 
| 87 | puts("<Optical>"); | 
| 88 | puts("<Layer>"); | 
| 89 | puts("\t<Material>"); | 
| 90 | printf("\t\t<Name>%s</Name>\n", bsdf_name[0] ? bsdf_name : "Unknown"); | 
| 91 | printf("\t\t<Manufacturer>%s</Manufacturer>\n", | 
| 92 | bsdf_manuf[0] ? bsdf_manuf : "Unknown"); | 
| 93 | puts("\t\t<DeviceType>Other</DeviceType>"); | 
| 94 | puts("\t</Material>"); | 
| 95 | puts("\t<DataDefinition>"); | 
| 96 | printf("\t\t<IncidentDataStructure>TensorTree%c</IncidentDataStructure>\n", | 
| 97 | single_plane_incident ? '3' : '4'); | 
| 98 | puts("\t</DataDefinition>"); | 
| 99 | } | 
| 100 |  | 
| 101 | /* Output XML data prologue to stdout */ | 
| 102 | static void | 
| 103 | data_prologue() | 
| 104 | { | 
| 105 | static const char       *bsdf_type[4] = { | 
| 106 | "Reflection Front", | 
| 107 | "Transmission Front", | 
| 108 | "Transmission Back", | 
| 109 | "Reflection Back" | 
| 110 | }; | 
| 111 |  | 
| 112 | puts("\t<WavelengthData>"); | 
| 113 | puts("\t\t<LayerNumber>System</LayerNumber>"); | 
| 114 | puts("\t\t<Wavelength unit=\"Integral\">Visible</Wavelength>"); | 
| 115 | puts("\t\t<SourceSpectrum>CIE Illuminant D65 1nm.ssp</SourceSpectrum>"); | 
| 116 | puts("\t\t<DetectorSpectrum>ASTM E308 1931 Y.dsp</DetectorSpectrum>"); | 
| 117 | puts("\t\t<WavelengthDataBlock>"); | 
| 118 | printf("\t\t\t<WavelengthDataDirection>%s</WavelengthDataDirection>\n", | 
| 119 | bsdf_type[(input_orient>0)<<1 | (output_orient>0)]); | 
| 120 | puts("\t\t\t<AngleBasis>LBNL/Shirley-Chiu</AngleBasis>"); | 
| 121 | puts("\t\t\t<ScatteringDataType>BTDF</ScatteringDataType>"); | 
| 122 | puts("\t\t\t<ScatteringData>"); | 
| 123 | } | 
| 124 |  | 
| 125 | /* Output XML data epilogue to stdout */ | 
| 126 | static void | 
| 127 | data_epilogue(void) | 
| 128 | { | 
| 129 | puts("\t\t\t</ScatteringData>"); | 
| 130 | puts("\t\t</WavelengthDataBlock>"); | 
| 131 | puts("\t</WavelengthData>"); | 
| 132 | } | 
| 133 |  | 
| 134 | /* Output XML epilogue to stdout */ | 
| 135 | static void | 
| 136 | xml_epilogue(void) | 
| 137 | { | 
| 138 | puts("</Layer>"); | 
| 139 | puts("</Optical>"); | 
| 140 | puts("</WindowElement>"); | 
| 141 | } | 
| 142 |  | 
| 143 | /* Compute absolute relative difference */ | 
| 144 | static double | 
| 145 | abs_diff(double v1, double v0) | 
| 146 | { | 
| 147 | if ((v0 < 0) | (v1 < 0)) | 
| 148 | return(.0); | 
| 149 | v1 = (v1-v0)*2./(v0+v1+.0001); | 
| 150 | if (v1 < 0) | 
| 151 | return(-v1); | 
| 152 | return(v1); | 
| 153 | } | 
| 154 |  | 
| 155 | /* Interpolate and output isotropic BSDF data */ | 
| 156 | static void | 
| 157 | eval_isotropic(char *funame) | 
| 158 | { | 
| 159 | const int       sqres = 1<<samp_order; | 
| 160 | FILE            *ofp = NULL; | 
| 161 | int             assignD = 0; | 
| 162 | char            cmd[128]; | 
| 163 | int             ix, ox, oy; | 
| 164 | double          iovec[6]; | 
| 165 | float           bsdf; | 
| 166 |  | 
| 167 | data_prologue();                        /* begin output */ | 
| 168 | if (pctcull >= 0) { | 
| 169 | sprintf(cmd, "rttree_reduce -a -h -ff -r 3 -t %f -g %d", | 
| 170 | pctcull, samp_order); | 
| 171 | fflush(stdout); | 
| 172 | ofp = popen(cmd, "w"); | 
| 173 | if (ofp == NULL) { | 
| 174 | fprintf(stderr, "%s: cannot create pipe to rttree_reduce\n", | 
| 175 | progname); | 
| 176 | exit(1); | 
| 177 | } | 
| 178 | SET_FILE_BINARY(ofp); | 
| 179 | #ifdef getc_unlocked                            /* avoid lock/unlock overhead */ | 
| 180 | flockfile(ofp); | 
| 181 | #endif | 
| 182 | } else | 
| 183 | fputs("{\n", stdout); | 
| 184 | /* need to assign Dx, Dy, Dz? */ | 
| 185 | if (funame != NULL) | 
| 186 | assignD = (fundefined(funame) < 6); | 
| 187 | /* run through directions */ | 
| 188 | for (ix = 0; ix < sqres/2; ix++) { | 
| 189 | RBFNODE *rbf = NULL; | 
| 190 | iovec[0] = 2.*(ix+.5)/sqres - 1.; | 
| 191 | iovec[1] = .0; | 
| 192 | iovec[2] = input_orient * sqrt(1. - iovec[0]*iovec[0]); | 
| 193 | if (funame == NULL) | 
| 194 | rbf = advect_rbf(iovec, lobe_lim); | 
| 195 | for (ox = 0; ox < sqres; ox++) { | 
| 196 | float       last_bsdf = -1; | 
| 197 | for (oy = 0; oy < sqres; oy++) { | 
| 198 | SDsquare2disk(iovec+3, (ox+.5)/sqres, (oy+.5)/sqres); | 
| 199 | iovec[5] = output_orient * | 
| 200 | sqrt(1. - iovec[3]*iovec[3] - iovec[4]*iovec[4]); | 
| 201 | if (funame == NULL) | 
| 202 | bsdf = eval_rbfrep(rbf, iovec+3) * | 
| 203 | output_orient/iovec[5]; | 
| 204 | else { | 
| 205 | if (assignD) { | 
| 206 | varset("Dx", '=', -iovec[3]); | 
| 207 | varset("Dy", '=', -iovec[4]); | 
| 208 | varset("Dz", '=', -iovec[5]); | 
| 209 | ++eclock; | 
| 210 | } | 
| 211 | bsdf = funvalue(funame, 6, iovec); | 
| 212 | #if (NSSAMP > 0) | 
| 213 | if (abs_diff(bsdf, last_bsdf) > ssamp_thresh) { | 
| 214 | int     ssi; | 
| 215 | double  ssa[3], ssvec[6], sum = 0; | 
| 216 | /* super-sample voxel */ | 
| 217 | for (ssi = NSSAMP; ssi--; ) { | 
| 218 | SDmultiSamp(ssa, 3, (ssi+frandom()) * | 
| 219 | (1./NSSAMP)); | 
| 220 | ssvec[0] = 2.*(ix+ssa[0])/sqres - 1.; | 
| 221 | ssvec[1] = .0; | 
| 222 | ssvec[2] = input_orient * | 
| 223 | sqrt(1. - ssvec[0]*ssvec[0]); | 
| 224 | SDsquare2disk(ssvec+3, (ox+ssa[1])/sqres, | 
| 225 | (oy+ssa[2])/sqres); | 
| 226 | ssvec[5] = output_orient * | 
| 227 | sqrt(1. - ssvec[3]*ssvec[3] - | 
| 228 | ssvec[4]*ssvec[4]); | 
| 229 | if (assignD) { | 
| 230 | varset("Dx", '=', -ssvec[3]); | 
| 231 | varset("Dy", '=', -ssvec[4]); | 
| 232 | varset("Dz", '=', -ssvec[5]); | 
| 233 | ++eclock; | 
| 234 | } | 
| 235 | sum += funvalue(funame, 6, ssvec); | 
| 236 | } | 
| 237 | bsdf = sum/NSSAMP; | 
| 238 | } | 
| 239 | #endif | 
| 240 | } | 
| 241 | if (pctcull >= 0) | 
| 242 | fwrite(&bsdf, sizeof(bsdf), 1, ofp); | 
| 243 | else | 
| 244 | printf("\t%.3e\n", bsdf); | 
| 245 | last_bsdf = bsdf; | 
| 246 | } | 
| 247 | } | 
| 248 | if (rbf != NULL) | 
| 249 | free(rbf); | 
| 250 | prog_show((ix+1.)*(2./sqres)); | 
| 251 | } | 
| 252 | if (pctcull >= 0) {                     /* finish output */ | 
| 253 | if (pclose(ofp)) { | 
| 254 | fprintf(stderr, "%s: error running '%s'\n", | 
| 255 | progname, cmd); | 
| 256 | exit(1); | 
| 257 | } | 
| 258 | } else { | 
| 259 | for (ix = sqres*sqres*sqres/2; ix--; ) | 
| 260 | fputs("\t0\n", stdout); | 
| 261 | fputs("}\n", stdout); | 
| 262 | } | 
| 263 | data_epilogue(); | 
| 264 | prog_done(); | 
| 265 | } | 
| 266 |  | 
| 267 | /* Interpolate and output anisotropic BSDF data */ | 
| 268 | static void | 
| 269 | eval_anisotropic(char *funame) | 
| 270 | { | 
| 271 | const int       sqres = 1<<samp_order; | 
| 272 | FILE            *ofp = NULL; | 
| 273 | int             assignD = 0; | 
| 274 | char            cmd[128]; | 
| 275 | int             ix, iy, ox, oy; | 
| 276 | double          iovec[6]; | 
| 277 | float           bsdf; | 
| 278 |  | 
| 279 | data_prologue();                        /* begin output */ | 
| 280 | if (pctcull >= 0) { | 
| 281 | sprintf(cmd, "rttree_reduce%s -h -ff -r 4 -t %f -g %d", | 
| 282 | (input_orient>0 ^ output_orient>0) ? "" : " -a", | 
| 283 | pctcull, samp_order); | 
| 284 | fflush(stdout); | 
| 285 | ofp = popen(cmd, "w"); | 
| 286 | if (ofp == NULL) { | 
| 287 | fprintf(stderr, "%s: cannot create pipe to rttree_reduce\n", | 
| 288 | progname); | 
| 289 | exit(1); | 
| 290 | } | 
| 291 | SET_FILE_BINARY(ofp); | 
| 292 | #ifdef getc_unlocked                            /* avoid lock/unlock overhead */ | 
| 293 | flockfile(ofp); | 
| 294 | #endif | 
| 295 | } else | 
| 296 | fputs("{\n", stdout); | 
| 297 | /* need to assign Dx, Dy, Dz? */ | 
| 298 | if (funame != NULL) | 
| 299 | assignD = (fundefined(funame) < 6); | 
| 300 | /* run through directions */ | 
| 301 | for (ix = 0; ix < sqres; ix++) | 
| 302 | for (iy = 0; iy < sqres; iy++) { | 
| 303 | RBFNODE *rbf = NULL;            /* Klems reversal */ | 
| 304 | SDsquare2disk(iovec, 1.-(ix+.5)/sqres, 1.-(iy+.5)/sqres); | 
| 305 | iovec[2] = input_orient * | 
| 306 | sqrt(1. - iovec[0]*iovec[0] - iovec[1]*iovec[1]); | 
| 307 | if (funame == NULL) | 
| 308 | rbf = advect_rbf(iovec, lobe_lim); | 
| 309 | for (ox = 0; ox < sqres; ox++) { | 
| 310 | float       last_bsdf = -1; | 
| 311 | for (oy = 0; oy < sqres; oy++) { | 
| 312 | SDsquare2disk(iovec+3, (ox+.5)/sqres, (oy+.5)/sqres); | 
| 313 | iovec[5] = output_orient * | 
| 314 | sqrt(1. - iovec[3]*iovec[3] - iovec[4]*iovec[4]); | 
| 315 | if (funame == NULL) | 
| 316 | bsdf = eval_rbfrep(rbf, iovec+3) * | 
| 317 | output_orient/iovec[5]; | 
| 318 | else { | 
| 319 | if (assignD) { | 
| 320 | varset("Dx", '=', -iovec[3]); | 
| 321 | varset("Dy", '=', -iovec[4]); | 
| 322 | varset("Dz", '=', -iovec[5]); | 
| 323 | ++eclock; | 
| 324 | } | 
| 325 | bsdf = funvalue(funame, 6, iovec); | 
| 326 | #if (NSSAMP > 0) | 
| 327 | if (abs_diff(bsdf, last_bsdf) > ssamp_thresh) { | 
| 328 | int     ssi; | 
| 329 | double  ssa[4], ssvec[6], sum = 0; | 
| 330 | /* super-sample voxel */ | 
| 331 | for (ssi = NSSAMP; ssi--; ) { | 
| 332 | SDmultiSamp(ssa, 4, (ssi+frandom()) * | 
| 333 | (1./NSSAMP)); | 
| 334 | SDsquare2disk(ssvec, 1.-(ix+ssa[0])/sqres, | 
| 335 | 1.-(iy+ssa[1])/sqres); | 
| 336 | ssvec[2] = input_orient * | 
| 337 | sqrt(1. - ssvec[0]*ssvec[0] - | 
| 338 | ssvec[1]*ssvec[1]); | 
| 339 | SDsquare2disk(ssvec+3, (ox+ssa[2])/sqres, | 
| 340 | (oy+ssa[3])/sqres); | 
| 341 | ssvec[5] = output_orient * | 
| 342 | sqrt(1. - ssvec[3]*ssvec[3] - | 
| 343 | ssvec[4]*ssvec[4]); | 
| 344 | if (assignD) { | 
| 345 | varset("Dx", '=', -ssvec[3]); | 
| 346 | varset("Dy", '=', -ssvec[4]); | 
| 347 | varset("Dz", '=', -ssvec[5]); | 
| 348 | ++eclock; | 
| 349 | } | 
| 350 | sum += funvalue(funame, 6, ssvec); | 
| 351 | } | 
| 352 | bsdf = sum/NSSAMP; | 
| 353 | } | 
| 354 | #endif | 
| 355 | } | 
| 356 | if (pctcull >= 0) | 
| 357 | fwrite(&bsdf, sizeof(bsdf), 1, ofp); | 
| 358 | else | 
| 359 | printf("\t%.3e\n", bsdf); | 
| 360 | last_bsdf = bsdf; | 
| 361 | } | 
| 362 | } | 
| 363 | if (rbf != NULL) | 
| 364 | free(rbf); | 
| 365 | prog_show((ix*sqres+iy+1.)/(sqres*sqres)); | 
| 366 | } | 
| 367 | if (pctcull >= 0) {                     /* finish output */ | 
| 368 | if (pclose(ofp)) { | 
| 369 | fprintf(stderr, "%s: error running '%s'\n", | 
| 370 | progname, cmd); | 
| 371 | exit(1); | 
| 372 | } | 
| 373 | } else | 
| 374 | fputs("}\n", stdout); | 
| 375 | data_epilogue(); | 
| 376 | prog_done(); | 
| 377 | } | 
| 378 |  | 
| 379 | /* Read in BSDF and interpolate as tensor tree representation */ | 
| 380 | int | 
| 381 | main(int argc, char *argv[]) | 
| 382 | { | 
| 383 | int     dofwd = 0, dobwd = 1; | 
| 384 | int     i, na; | 
| 385 |  | 
| 386 | progname = argv[0]; | 
| 387 | esupport |= E_VARIABLE|E_FUNCTION|E_RCONST; | 
| 388 | esupport &= ~(E_INCHAN|E_OUTCHAN); | 
| 389 | scompile("PI:3.14159265358979323846", NULL, 0); | 
| 390 | biggerlib(); | 
| 391 | for (i = 1; i < argc-1 && (argv[i][0] == '-') | (argv[i][0] == '+'); i++) | 
| 392 | switch (argv[i][1]) {           /* get options */ | 
| 393 | case 'e': | 
| 394 | scompile(argv[++i], NULL, 0); | 
| 395 | break; | 
| 396 | case 'f': | 
| 397 | if (!argv[i][2]) | 
| 398 | fcompile(argv[++i]); | 
| 399 | else | 
| 400 | dofwd = (argv[i][0] == '+'); | 
| 401 | break; | 
| 402 | case 'b': | 
| 403 | dobwd = (argv[i][0] == '+'); | 
| 404 | break; | 
| 405 | case 't': | 
| 406 | switch (argv[i][2]) { | 
| 407 | case '3': | 
| 408 | single_plane_incident = 1; | 
| 409 | break; | 
| 410 | case '4': | 
| 411 | single_plane_incident = 0; | 
| 412 | break; | 
| 413 | case '\0': | 
| 414 | pctcull = atof(argv[++i]); | 
| 415 | break; | 
| 416 | default: | 
| 417 | goto userr; | 
| 418 | } | 
| 419 | break; | 
| 420 | case 'g': | 
| 421 | samp_order = atoi(argv[++i]); | 
| 422 | break; | 
| 423 | case 'l': | 
| 424 | lobe_lim = atoi(argv[++i]); | 
| 425 | break; | 
| 426 | case 'p': | 
| 427 | do_prog = atoi(argv[i]+2); | 
| 428 | break; | 
| 429 | default: | 
| 430 | goto userr; | 
| 431 | } | 
| 432 | if (single_plane_incident >= 0) {       /* function-based BSDF? */ | 
| 433 | void    (*evf)(char *s) = single_plane_incident ? | 
| 434 | &eval_isotropic : &eval_anisotropic; | 
| 435 | if (i != argc-1 || fundefined(argv[i]) < 3) { | 
| 436 | fprintf(stderr, | 
| 437 | "%s: need single function with 6 arguments: bsdf(ix,iy,iz,ox,oy,oz)\n", | 
| 438 | progname); | 
| 439 | fprintf(stderr, "\tor 3 arguments using Dx,Dy,Dz: bsdf(ix,iy,iz)\n"); | 
| 440 | goto userr; | 
| 441 | } | 
| 442 | ++eclock; | 
| 443 | xml_prologue(argc, argv);       /* start XML output */ | 
| 444 | if (dofwd) { | 
| 445 | input_orient = -1; | 
| 446 | output_orient = -1; | 
| 447 | prog_start("Evaluating outside reflectance"); | 
| 448 | (*evf)(argv[i]); | 
| 449 | output_orient = 1; | 
| 450 | prog_start("Evaluating outside->inside transmission"); | 
| 451 | (*evf)(argv[i]); | 
| 452 | } | 
| 453 | if (dobwd) { | 
| 454 | input_orient = 1; | 
| 455 | output_orient = 1; | 
| 456 | prog_start("Evaluating inside reflectance"); | 
| 457 | (*evf)(argv[i]); | 
| 458 | output_orient = -1; | 
| 459 | prog_start("Evaluating inside->outside transmission"); | 
| 460 | (*evf)(argv[i]); | 
| 461 | } | 
| 462 | xml_epilogue();                 /* finish XML output & exit */ | 
| 463 | return(0); | 
| 464 | } | 
| 465 | if (i < argc) {                         /* open input files if given */ | 
| 466 | int     nbsdf = 0; | 
| 467 | for ( ; i < argc; i++) {        /* interpolate each component */ | 
| 468 | char    pbuf[256]; | 
| 469 | FILE    *fpin = fopen(argv[i], "rb"); | 
| 470 | if (fpin == NULL) { | 
| 471 | fprintf(stderr, "%s: cannot open BSDF interpolant '%s'\n", | 
| 472 | progname, argv[i]); | 
| 473 | return(1); | 
| 474 | } | 
| 475 | if (!load_bsdf_rep(fpin)) | 
| 476 | return(1); | 
| 477 | fclose(fpin); | 
| 478 | if (!nbsdf++)           /* start XML on first dist. */ | 
| 479 | xml_prologue(argc, argv); | 
| 480 | sprintf(pbuf, "Interpolating component '%s'", argv[i]); | 
| 481 | prog_start(pbuf); | 
| 482 | if (single_plane_incident) | 
| 483 | eval_isotropic(NULL); | 
| 484 | else | 
| 485 | eval_anisotropic(NULL); | 
| 486 | } | 
| 487 | xml_epilogue();                 /* finish XML output & exit */ | 
| 488 | return(0); | 
| 489 | } | 
| 490 | SET_FILE_BINARY(stdin);                 /* load from stdin */ | 
| 491 | if (!load_bsdf_rep(stdin)) | 
| 492 | return(1); | 
| 493 | xml_prologue(argc, argv);               /* start XML output */ | 
| 494 | prog_start("Interpolating from standard input"); | 
| 495 | if (single_plane_incident)              /* resample dist. */ | 
| 496 | eval_isotropic(NULL); | 
| 497 | else | 
| 498 | eval_anisotropic(NULL); | 
| 499 | xml_epilogue();                         /* finish XML output & exit */ | 
| 500 | return(0); | 
| 501 | userr: | 
| 502 | fprintf(stderr, | 
| 503 | "Usage: %s [-g Nlog2][-t pctcull][-l maxlobes] [bsdf.sir ..] > bsdf.xml\n", | 
| 504 | progname); | 
| 505 | fprintf(stderr, | 
| 506 | "   or: %s -t{3|4} [-g Nlog2][-t pctcull][{+|-}for[ward]][{+|-}b[ackward]][-e expr][-f file] bsdf_func > bsdf.xml\n", | 
| 507 | progname); | 
| 508 | return(1); | 
| 509 | } |