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root/radiance/ray/src/cv/bsdfrep.c
Revision: 2.25
Committed: Thu Aug 21 10:33:48 2014 UTC (9 years, 8 months ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.24: +52 -6 lines
Log Message:
Added grazing angle extrapolation to BSDF interpolation

File Contents

# User Rev Content
1 greg 2.1 #ifndef lint
2 greg 2.25 static const char RCSid[] = "$Id: bsdfrep.c,v 2.24 2014/03/25 14:55:35 greg Exp $";
3 greg 2.1 #endif
4     /*
5     * Support BSDF representation as radial basis functions.
6     *
7     * G. Ward
8     */
9    
10     #define _USE_MATH_DEFINES
11     #include <stdlib.h>
12 greg 2.2 #include <string.h>
13 greg 2.1 #include <math.h>
14     #include "rtio.h"
15     #include "resolu.h"
16     #include "bsdfrep.h"
17 greg 2.19 /* name and manufacturer if known */
18     char bsdf_name[256];
19     char bsdf_manuf[256];
20 greg 2.5 /* active grid resolution */
21     int grid_res = GRIDRES;
22    
23 greg 2.4 /* coverage/symmetry using INP_QUAD? flags */
24 greg 2.1 int inp_coverage = 0;
25     /* all incident angles in-plane so far? */
26     int single_plane_incident = -1;
27    
28     /* input/output orientations */
29     int input_orient = 0;
30     int output_orient = 0;
31    
32 greg 2.12 /* BSDF histogram */
33 greg 2.15 unsigned long bsdf_hist[HISTLEN];
34 greg 2.12
35     /* BSDF value for boundary regions */
36     double bsdf_min = 0;
37 greg 2.25 float bsdf_spec_peak = 0;
38     int bsdf_spec_crad = 0;
39 greg 2.12
40 greg 2.1 /* processed incident DSF measurements */
41     RBFNODE *dsf_list = NULL;
42    
43     /* RBF-linking matrices (edges) */
44     MIGRATION *mig_list = NULL;
45    
46     /* current input direction */
47     double theta_in_deg, phi_in_deg;
48    
49     /* Register new input direction */
50     int
51     new_input_direction(double new_theta, double new_phi)
52     {
53     if (!input_orient) /* check input orientation */
54     input_orient = 1 - 2*(new_theta > 90.);
55     else if (input_orient > 0 ^ new_theta < 90.) {
56     fprintf(stderr,
57     "%s: Cannot handle input angles on both sides of surface\n",
58     progname);
59     return(0);
60     }
61     /* normalize angle ranges */
62     while (new_theta < -180.)
63     new_theta += 360.;
64     while (new_theta > 180.)
65     new_theta -= 360.;
66     if (new_theta < 0) {
67     new_theta = -new_theta;
68     new_phi += 180.;
69     }
70 greg 2.6 if ((theta_in_deg = new_theta) < 1.0)
71     return(1); /* don't rely on phi near normal */
72 greg 2.1 while (new_phi < 0)
73     new_phi += 360.;
74     while (new_phi >= 360.)
75     new_phi -= 360.;
76     if (single_plane_incident > 0) /* check input coverage */
77     single_plane_incident = (round(new_phi) == round(phi_in_deg));
78     else if (single_plane_incident < 0)
79     single_plane_incident = 1;
80     phi_in_deg = new_phi;
81     if ((1. < new_phi) & (new_phi < 89.))
82     inp_coverage |= INP_QUAD1;
83     else if ((91. < new_phi) & (new_phi < 179.))
84     inp_coverage |= INP_QUAD2;
85     else if ((181. < new_phi) & (new_phi < 269.))
86     inp_coverage |= INP_QUAD3;
87     else if ((271. < new_phi) & (new_phi < 359.))
88     inp_coverage |= INP_QUAD4;
89     return(1);
90     }
91    
92     /* Apply symmetry to the given vector based on distribution */
93     int
94     use_symmetry(FVECT vec)
95     {
96 greg 2.11 const double phi = get_phi360(vec);
97 greg 2.1
98     switch (inp_coverage) {
99     case INP_QUAD1|INP_QUAD2|INP_QUAD3|INP_QUAD4:
100     break;
101     case INP_QUAD1|INP_QUAD2:
102     if ((-FTINY > phi) | (phi > 180.+FTINY))
103     goto mir_y;
104     break;
105     case INP_QUAD2|INP_QUAD3:
106     if ((90.-FTINY > phi) | (phi > 270.+FTINY))
107     goto mir_x;
108     break;
109     case INP_QUAD3|INP_QUAD4:
110     if ((180.-FTINY > phi) | (phi > 360.+FTINY))
111     goto mir_y;
112     break;
113     case INP_QUAD4|INP_QUAD1:
114     if ((270.-FTINY > phi) & (phi > 90.+FTINY))
115     goto mir_x;
116     break;
117     case INP_QUAD1:
118     if ((-FTINY > phi) | (phi > 90.+FTINY))
119     switch ((int)(phi*(1./90.))) {
120     case 1: goto mir_x;
121     case 2: goto mir_xy;
122     case 3: goto mir_y;
123     }
124     break;
125     case INP_QUAD2:
126     if ((90.-FTINY > phi) | (phi > 180.+FTINY))
127     switch ((int)(phi*(1./90.))) {
128     case 0: goto mir_x;
129     case 2: goto mir_y;
130     case 3: goto mir_xy;
131     }
132     break;
133     case INP_QUAD3:
134     if ((180.-FTINY > phi) | (phi > 270.+FTINY))
135     switch ((int)(phi*(1./90.))) {
136     case 0: goto mir_xy;
137     case 1: goto mir_y;
138     case 3: goto mir_x;
139     }
140     break;
141     case INP_QUAD4:
142     if ((270.-FTINY > phi) | (phi > 360.+FTINY))
143     switch ((int)(phi*(1./90.))) {
144     case 0: goto mir_y;
145     case 1: goto mir_xy;
146     case 2: goto mir_x;
147     }
148     break;
149     default:
150     fprintf(stderr, "%s: Illegal input coverage (%d)\n",
151     progname, inp_coverage);
152     exit(1);
153     }
154     return(0); /* in range */
155     mir_x:
156     vec[0] = -vec[0];
157     return(MIRROR_X);
158     mir_y:
159     vec[1] = -vec[1];
160     return(MIRROR_Y);
161     mir_xy:
162     vec[0] = -vec[0];
163     vec[1] = -vec[1];
164     return(MIRROR_X|MIRROR_Y);
165     }
166    
167     /* Reverse symmetry based on what was done before */
168     void
169     rev_symmetry(FVECT vec, int sym)
170     {
171     if (sym & MIRROR_X)
172     vec[0] = -vec[0];
173     if (sym & MIRROR_Y)
174     vec[1] = -vec[1];
175     }
176    
177     /* Reverse symmetry for an RBF distribution */
178     void
179     rev_rbf_symmetry(RBFNODE *rbf, int sym)
180     {
181     int n;
182    
183     rev_symmetry(rbf->invec, sym);
184     if (sym & MIRROR_X)
185     for (n = rbf->nrbf; n-- > 0; )
186 greg 2.5 rbf->rbfa[n].gx = grid_res-1 - rbf->rbfa[n].gx;
187 greg 2.1 if (sym & MIRROR_Y)
188     for (n = rbf->nrbf; n-- > 0; )
189 greg 2.5 rbf->rbfa[n].gy = grid_res-1 - rbf->rbfa[n].gy;
190 greg 2.1 }
191    
192 greg 2.6 /* Rotate RBF to correspond to given incident vector */
193     void
194     rotate_rbf(RBFNODE *rbf, const FVECT invec)
195     {
196     static const FVECT vnorm = {.0, .0, 1.};
197     const double phi = atan2(invec[1],invec[0]) -
198     atan2(rbf->invec[1],rbf->invec[0]);
199     FVECT outvec;
200     int pos[2];
201     int n;
202 greg 2.8
203 greg 2.24 for (n = (cos(phi) < 1.-FTINY)*rbf->nrbf; n-- > 0; ) {
204 greg 2.6 ovec_from_pos(outvec, rbf->rbfa[n].gx, rbf->rbfa[n].gy);
205     spinvector(outvec, outvec, vnorm, phi);
206     pos_from_vec(pos, outvec);
207     rbf->rbfa[n].gx = pos[0];
208     rbf->rbfa[n].gy = pos[1];
209     }
210     VCOPY(rbf->invec, invec);
211     }
212    
213 greg 2.1 /* Compute outgoing vector from grid position */
214     void
215     ovec_from_pos(FVECT vec, int xpos, int ypos)
216     {
217     double uv[2];
218     double r2;
219    
220 greg 2.8 SDsquare2disk(uv, (xpos+.5)/grid_res, (ypos+.5)/grid_res);
221 greg 2.1 /* uniform hemispherical projection */
222     r2 = uv[0]*uv[0] + uv[1]*uv[1];
223     vec[0] = vec[1] = sqrt(2. - r2);
224     vec[0] *= uv[0];
225     vec[1] *= uv[1];
226     vec[2] = output_orient*(1. - r2);
227     }
228    
229     /* Compute grid position from normalized input/output vector */
230     void
231     pos_from_vec(int pos[2], const FVECT vec)
232     {
233     double sq[2]; /* uniform hemispherical projection */
234     double norm = 1./sqrt(1. + fabs(vec[2]));
235    
236     SDdisk2square(sq, vec[0]*norm, vec[1]*norm);
237    
238 greg 2.5 pos[0] = (int)(sq[0]*grid_res);
239     pos[1] = (int)(sq[1]*grid_res);
240 greg 2.1 }
241    
242 greg 2.14 /* Compute volume associated with Gaussian lobe */
243     double
244     rbf_volume(const RBFVAL *rbfp)
245     {
246     double rad = R2ANG(rbfp->crad);
247     FVECT odir;
248     double elev, integ;
249     /* infinite integral approximation */
250     integ = (2.*M_PI) * rbfp->peak * rad*rad;
251     /* check if we're near horizon */
252     ovec_from_pos(odir, rbfp->gx, rbfp->gy);
253     elev = output_orient*odir[2];
254     /* apply cut-off correction if > 1% */
255     if (elev < 2.8*rad) {
256     /* elev = asin(elev); /* this is so crude, anyway... */
257     integ *= 1. - .5*exp(-.5*elev*elev/(rad*rad));
258     }
259     return(integ);
260     }
261    
262 greg 2.25 /* Evaluate BSDF at the given normalized outgoing direction */
263 greg 2.1 double
264     eval_rbfrep(const RBFNODE *rp, const FVECT outvec)
265     {
266 greg 2.17 const double rfact2 = (38./M_PI/M_PI)*(grid_res*grid_res);
267 greg 2.16 int pos[2];
268 greg 2.8 double res = 0;
269 greg 2.1 const RBFVAL *rbfp;
270     FVECT odir;
271 greg 2.16 double rad2;
272 greg 2.1 int n;
273 greg 2.14 /* check for wrong side */
274     if (outvec[2] > 0 ^ output_orient > 0)
275     return(.0);
276 greg 2.12 /* use minimum if no information avail. */
277 greg 2.14 if (rp == NULL)
278 greg 2.25 return(bsdf_min);
279 greg 2.16 /* optimization for fast lobe culling */
280     pos_from_vec(pos, outvec);
281 greg 2.14 /* sum radial basis function */
282 greg 2.1 rbfp = rp->rbfa;
283     for (n = rp->nrbf; n--; rbfp++) {
284 greg 2.16 int d2 = (pos[0]-rbfp->gx)*(pos[0]-rbfp->gx) +
285     (pos[1]-rbfp->gy)*(pos[1]-rbfp->gy);
286     rad2 = R2ANG(rbfp->crad);
287     rad2 *= rad2;
288 greg 2.17 if (d2 > rad2*rfact2)
289 greg 2.16 continue;
290 greg 2.1 ovec_from_pos(odir, rbfp->gx, rbfp->gy);
291 greg 2.16 res += rbfp->peak * exp((DOT(odir,outvec) - 1.) / rad2);
292 greg 2.1 }
293 greg 2.25 res /= output_orient*outvec[2];
294     if (res < bsdf_min) /* never return less than bsdf_min */
295     return(bsdf_min);
296 greg 2.1 return(res);
297     }
298    
299     /* Insert a new directional scattering function in our global list */
300     int
301     insert_dsf(RBFNODE *newrbf)
302     {
303     RBFNODE *rbf, *rbf_last;
304     int pos;
305     /* check for redundant meas. */
306     for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
307     if (DOT(rbf->invec, newrbf->invec) >= 1.-FTINY) {
308     fprintf(stderr,
309 greg 2.22 "%s: Duplicate incident measurement ignored at (%.1f,%.1f)\n",
310     progname, get_theta180(newrbf->invec),
311     get_phi360(newrbf->invec));
312 greg 2.1 free(newrbf);
313     return(-1);
314     }
315     /* keep in ascending theta order */
316     for (rbf_last = NULL, rbf = dsf_list; rbf != NULL;
317     rbf_last = rbf, rbf = rbf->next)
318     if (single_plane_incident && input_orient*rbf->invec[2] <
319     input_orient*newrbf->invec[2])
320     break;
321     if (rbf_last == NULL) { /* insert new node in list */
322     newrbf->ord = 0;
323     newrbf->next = dsf_list;
324     dsf_list = newrbf;
325     } else {
326     newrbf->ord = rbf_last->ord + 1;
327     newrbf->next = rbf;
328     rbf_last->next = newrbf;
329     }
330     rbf_last = newrbf;
331     while (rbf != NULL) { /* update ordinal positions */
332     rbf->ord = rbf_last->ord + 1;
333     rbf_last = rbf;
334     rbf = rbf->next;
335     }
336     return(newrbf->ord);
337     }
338    
339     /* Get the DSF indicated by its ordinal position */
340     RBFNODE *
341     get_dsf(int ord)
342     {
343     RBFNODE *rbf;
344    
345     for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
346 greg 2.3 if (rbf->ord == ord)
347 greg 2.1 return(rbf);
348     return(NULL);
349     }
350    
351     /* Get triangle surface orientation (unnormalized) */
352     void
353     tri_orient(FVECT vres, const FVECT v1, const FVECT v2, const FVECT v3)
354     {
355     FVECT v2minus1, v3minus2;
356    
357     VSUB(v2minus1, v2, v1);
358     VSUB(v3minus2, v3, v2);
359     VCROSS(vres, v2minus1, v3minus2);
360     }
361    
362     /* Determine if vertex order is reversed (inward normal) */
363     int
364     is_rev_tri(const FVECT v1, const FVECT v2, const FVECT v3)
365     {
366     FVECT tor;
367    
368     tri_orient(tor, v1, v2, v3);
369    
370     return(DOT(tor, v2) < 0.);
371     }
372    
373     /* Find vertices completing triangles on either side of the given edge */
374     int
375     get_triangles(RBFNODE *rbfv[2], const MIGRATION *mig)
376     {
377 greg 2.4 const MIGRATION *ej1, *ej2;
378 greg 2.1 RBFNODE *tv;
379    
380     rbfv[0] = rbfv[1] = NULL;
381     if (mig == NULL)
382     return(0);
383 greg 2.4 for (ej1 = mig->rbfv[0]->ejl; ej1 != NULL;
384     ej1 = nextedge(mig->rbfv[0],ej1)) {
385     if (ej1 == mig)
386 greg 2.1 continue;
387 greg 2.4 tv = opp_rbf(mig->rbfv[0],ej1);
388 greg 2.1 for (ej2 = tv->ejl; ej2 != NULL; ej2 = nextedge(tv,ej2))
389     if (opp_rbf(tv,ej2) == mig->rbfv[1]) {
390     rbfv[is_rev_tri(mig->rbfv[0]->invec,
391     mig->rbfv[1]->invec,
392     tv->invec)] = tv;
393     break;
394     }
395     }
396     return((rbfv[0] != NULL) + (rbfv[1] != NULL));
397     }
398    
399 greg 2.25 /* Return single-lobe specular RBF for the given incident direction */
400     RBFNODE *
401     def_rbf_spec(const FVECT invec)
402     {
403     RBFNODE *rbf;
404     FVECT ovec;
405     int pos[2];
406    
407     if (input_orient > 0 ^ invec[2] > 0) /* wrong side? */
408     return(NULL);
409     if ((bsdf_spec_peak <= bsdf_min) | (bsdf_spec_crad <= 0))
410     return(NULL); /* nothing set */
411     rbf = (RBFNODE *)malloc(sizeof(RBFNODE));
412     if (rbf == NULL)
413     return(NULL);
414     ovec[0] = -invec[0];
415     ovec[1] = -invec[1];
416     ovec[2] = invec[2]*(2*(input_orient==output_orient) - 1);
417     pos_from_vec(pos, ovec);
418     rbf->ord = 0;
419     rbf->next = NULL;
420     rbf->ejl = NULL;
421     VCOPY(rbf->invec, invec);
422     rbf->nrbf = 1;
423     rbf->rbfa[0].peak = bsdf_spec_peak * output_orient*ovec[2];
424     rbf->rbfa[0].crad = bsdf_spec_crad;
425     rbf->rbfa[0].gx = pos[0];
426     rbf->rbfa[0].gy = pos[1];
427     rbf->vtotal = rbf_volume(rbf->rbfa);
428     return(rbf);
429     }
430    
431 greg 2.20 /* Advect and allocate new RBF along edge (internal call) */
432     RBFNODE *
433     e_advect_rbf(const MIGRATION *mig, const FVECT invec, int lobe_lim)
434     {
435     double cthresh = FTINY;
436     RBFNODE *rbf;
437     int n, i, j;
438     double t, full_dist;
439     /* get relative position */
440     t = Acos(DOT(invec, mig->rbfv[0]->invec));
441     if (t < M_PI/grid_res) { /* near first DSF */
442     n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[0]->nrbf-1);
443     rbf = (RBFNODE *)malloc(n);
444     if (rbf == NULL)
445     goto memerr;
446     memcpy(rbf, mig->rbfv[0], n); /* just duplicate */
447     rbf->next = NULL; rbf->ejl = NULL;
448     return(rbf);
449     }
450     full_dist = acos(DOT(mig->rbfv[0]->invec, mig->rbfv[1]->invec));
451     if (t > full_dist-M_PI/grid_res) { /* near second DSF */
452     n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[1]->nrbf-1);
453     rbf = (RBFNODE *)malloc(n);
454     if (rbf == NULL)
455     goto memerr;
456     memcpy(rbf, mig->rbfv[1], n); /* just duplicate */
457     rbf->next = NULL; rbf->ejl = NULL;
458     return(rbf);
459     }
460     t /= full_dist;
461     tryagain:
462     n = 0; /* count migrating particles */
463     for (i = 0; i < mtx_nrows(mig); i++)
464     for (j = 0; j < mtx_ncols(mig); j++)
465     n += (mtx_coef(mig,i,j) > cthresh);
466     /* are we over our limit? */
467     if ((lobe_lim > 0) & (n > lobe_lim)) {
468     cthresh = cthresh*2. + 10.*FTINY;
469     goto tryagain;
470     }
471     #ifdef DEBUG
472     fprintf(stderr, "Input RBFs have %d, %d nodes -> output has %d\n",
473     mig->rbfv[0]->nrbf, mig->rbfv[1]->nrbf, n);
474     #endif
475     rbf = (RBFNODE *)malloc(sizeof(RBFNODE) + sizeof(RBFVAL)*(n-1));
476     if (rbf == NULL)
477     goto memerr;
478     rbf->next = NULL; rbf->ejl = NULL;
479     VCOPY(rbf->invec, invec);
480     rbf->nrbf = n;
481     rbf->vtotal = 1.-t + t*mig->rbfv[1]->vtotal/mig->rbfv[0]->vtotal;
482     n = 0; /* advect RBF lobes */
483     for (i = 0; i < mtx_nrows(mig); i++) {
484     const RBFVAL *rbf0i = &mig->rbfv[0]->rbfa[i];
485     const float peak0 = rbf0i->peak;
486     const double rad0 = R2ANG(rbf0i->crad);
487     FVECT v0;
488     float mv;
489     ovec_from_pos(v0, rbf0i->gx, rbf0i->gy);
490     for (j = 0; j < mtx_ncols(mig); j++)
491     if ((mv = mtx_coef(mig,i,j)) > cthresh) {
492     const RBFVAL *rbf1j = &mig->rbfv[1]->rbfa[j];
493     double rad2;
494     FVECT v;
495     int pos[2];
496     rad2 = R2ANG(rbf1j->crad);
497     rad2 = rad0*rad0*(1.-t) + rad2*rad2*t;
498     rbf->rbfa[n].peak = peak0 * mv * rbf->vtotal *
499     rad0*rad0/rad2;
500     rbf->rbfa[n].crad = ANG2R(sqrt(rad2));
501     ovec_from_pos(v, rbf1j->gx, rbf1j->gy);
502     geodesic(v, v0, v, t, GEOD_REL);
503     pos_from_vec(pos, v);
504     rbf->rbfa[n].gx = pos[0];
505     rbf->rbfa[n].gy = pos[1];
506     ++n;
507     }
508     }
509     rbf->vtotal *= mig->rbfv[0]->vtotal; /* turn ratio into actual */
510     return(rbf);
511     memerr:
512     fprintf(stderr, "%s: Out of memory in e_advect_rbf()\n", progname);
513     exit(1);
514     return(NULL); /* pro forma return */
515     }
516    
517 greg 2.4 /* Clear our BSDF representation and free memory */
518     void
519     clear_bsdf_rep(void)
520     {
521     while (mig_list != NULL) {
522     MIGRATION *mig = mig_list;
523     mig_list = mig->next;
524     free(mig);
525     }
526     while (dsf_list != NULL) {
527     RBFNODE *rbf = dsf_list;
528     dsf_list = rbf->next;
529     free(rbf);
530     }
531 greg 2.19 bsdf_name[0] = '\0';
532     bsdf_manuf[0] = '\0';
533 greg 2.4 inp_coverage = 0;
534     single_plane_incident = -1;
535     input_orient = output_orient = 0;
536 greg 2.5 grid_res = GRIDRES;
537 greg 2.25 bsdf_min = 0;
538     bsdf_spec_peak = 0;
539     bsdf_spec_crad = 0;
540 greg 2.4 }
541    
542 greg 2.1 /* Write our BSDF mesh interpolant out to the given binary stream */
543     void
544     save_bsdf_rep(FILE *ofp)
545     {
546     RBFNODE *rbf;
547     MIGRATION *mig;
548     int i, n;
549     /* finish header */
550 greg 2.19 if (bsdf_name[0])
551     fprintf(ofp, "NAME=%s\n", bsdf_name);
552     if (bsdf_manuf[0])
553     fprintf(ofp, "MANUFACT=%s\n", bsdf_manuf);
554 greg 2.2 fprintf(ofp, "SYMMETRY=%d\n", !single_plane_incident * inp_coverage);
555     fprintf(ofp, "IO_SIDES= %d %d\n", input_orient, output_orient);
556 greg 2.5 fprintf(ofp, "GRIDRES=%d\n", grid_res);
557 greg 2.12 fprintf(ofp, "BSDFMIN=%g\n", bsdf_min);
558 greg 2.25 if ((bsdf_spec_peak > bsdf_min) & (bsdf_spec_crad > 0))
559     fprintf(ofp, "BSDFSPEC= %f %f\n", bsdf_spec_peak,
560     R2ANG(bsdf_spec_crad));
561 greg 2.1 fputformat(BSDFREP_FMT, ofp);
562     fputc('\n', ofp);
563     /* write each DSF */
564     for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
565     putint(rbf->ord, 4, ofp);
566     putflt(rbf->invec[0], ofp);
567     putflt(rbf->invec[1], ofp);
568     putflt(rbf->invec[2], ofp);
569     putflt(rbf->vtotal, ofp);
570     putint(rbf->nrbf, 4, ofp);
571     for (i = 0; i < rbf->nrbf; i++) {
572     putflt(rbf->rbfa[i].peak, ofp);
573     putint(rbf->rbfa[i].crad, 2, ofp);
574     putint(rbf->rbfa[i].gx, 1, ofp);
575     putint(rbf->rbfa[i].gy, 1, ofp);
576     }
577     }
578     putint(-1, 4, ofp); /* terminator */
579     /* write each migration matrix */
580 greg 2.2 for (mig = mig_list; mig != NULL; mig = mig->next) {
581     int zerocnt = 0;
582 greg 2.1 putint(mig->rbfv[0]->ord, 4, ofp);
583     putint(mig->rbfv[1]->ord, 4, ofp);
584 greg 2.2 /* write out as sparse data */
585 greg 2.1 n = mtx_nrows(mig) * mtx_ncols(mig);
586 greg 2.2 for (i = 0; i < n; i++) {
587 greg 2.3 if (zerocnt == 0xff) {
588     putint(0xff, 1, ofp); zerocnt = 0;
589 greg 2.2 }
590     if (mig->mtx[i] != 0) {
591     putint(zerocnt, 1, ofp); zerocnt = 0;
592     putflt(mig->mtx[i], ofp);
593     } else
594     ++zerocnt;
595     }
596     putint(zerocnt, 1, ofp);
597 greg 2.1 }
598     putint(-1, 4, ofp); /* terminator */
599     putint(-1, 4, ofp);
600     if (fflush(ofp) == EOF) {
601     fprintf(stderr, "%s: error writing BSDF interpolant\n",
602     progname);
603     exit(1);
604     }
605     }
606    
607 greg 2.2 /* Check header line for critical information */
608     static int
609     headline(char *s, void *p)
610     {
611     char fmt[32];
612    
613 greg 2.19 if (!strncmp(s, "NAME=", 5)) {
614     strcpy(bsdf_name, s+5);
615     bsdf_name[strlen(bsdf_name)-1] = '\0';
616     }
617     if (!strncmp(s, "MANUFACT=", 9)) {
618     strcpy(bsdf_manuf, s+9);
619     bsdf_manuf[strlen(bsdf_manuf)-1] = '\0';
620     }
621 greg 2.2 if (!strncmp(s, "SYMMETRY=", 9)) {
622     inp_coverage = atoi(s+9);
623     single_plane_incident = !inp_coverage;
624     return(0);
625     }
626     if (!strncmp(s, "IO_SIDES=", 9)) {
627     sscanf(s+9, "%d %d", &input_orient, &output_orient);
628     return(0);
629     }
630 greg 2.5 if (!strncmp(s, "GRIDRES=", 8)) {
631     sscanf(s+8, "%d", &grid_res);
632     return(0);
633     }
634 greg 2.12 if (!strncmp(s, "BSDFMIN=", 8)) {
635     sscanf(s+8, "%lf", &bsdf_min);
636     return(0);
637     }
638 greg 2.25 if (!strncmp(s, "BSDFSPEC=", 9)) {
639     float bsdf_spec_rad = 0;
640     sscanf(s+9, "%f %f", &bsdf_spec_peak, &bsdf_spec_rad);
641     bsdf_spec_crad = ANG2R(bsdf_spec_rad);
642     return(0);
643     }
644 greg 2.2 if (formatval(fmt, s) && strcmp(fmt, BSDFREP_FMT))
645     return(-1);
646     return(0);
647     }
648    
649 greg 2.1 /* Read a BSDF mesh interpolant from the given binary stream */
650     int
651     load_bsdf_rep(FILE *ifp)
652     {
653     RBFNODE rbfh;
654     int from_ord, to_ord;
655     int i;
656 greg 2.4
657     clear_bsdf_rep();
658 greg 2.5 if (ifp == NULL)
659     return(0);
660 greg 2.21 if (getheader(ifp, headline, NULL) < 0 || (single_plane_incident < 0) |
661 greg 2.23 !input_orient | !output_orient |
662     (grid_res < 16) | (grid_res > 256)) {
663 greg 2.1 fprintf(stderr, "%s: missing/bad format for BSDF interpolant\n",
664     progname);
665     return(0);
666     }
667 greg 2.18 memset(&rbfh, 0, sizeof(rbfh)); /* read each DSF */
668 greg 2.1 while ((rbfh.ord = getint(4, ifp)) >= 0) {
669     RBFNODE *newrbf;
670    
671     rbfh.invec[0] = getflt(ifp);
672     rbfh.invec[1] = getflt(ifp);
673     rbfh.invec[2] = getflt(ifp);
674 greg 2.9 if (normalize(rbfh.invec) == 0) {
675     fprintf(stderr, "%s: zero incident vector\n", progname);
676     return(0);
677     }
678 greg 2.3 rbfh.vtotal = getflt(ifp);
679 greg 2.1 rbfh.nrbf = getint(4, ifp);
680     newrbf = (RBFNODE *)malloc(sizeof(RBFNODE) +
681     sizeof(RBFVAL)*(rbfh.nrbf-1));
682     if (newrbf == NULL)
683     goto memerr;
684 greg 2.18 *newrbf = rbfh;
685 greg 2.1 for (i = 0; i < rbfh.nrbf; i++) {
686     newrbf->rbfa[i].peak = getflt(ifp);
687     newrbf->rbfa[i].crad = getint(2, ifp) & 0xffff;
688     newrbf->rbfa[i].gx = getint(1, ifp) & 0xff;
689     newrbf->rbfa[i].gy = getint(1, ifp) & 0xff;
690     }
691     if (feof(ifp))
692     goto badEOF;
693     /* insert in global list */
694     if (insert_dsf(newrbf) != rbfh.ord) {
695     fprintf(stderr, "%s: error adding DSF\n", progname);
696     return(0);
697     }
698     }
699     /* read each migration matrix */
700     while ((from_ord = getint(4, ifp)) >= 0 &&
701     (to_ord = getint(4, ifp)) >= 0) {
702     RBFNODE *from_rbf = get_dsf(from_ord);
703     RBFNODE *to_rbf = get_dsf(to_ord);
704     MIGRATION *newmig;
705     int n;
706    
707     if ((from_rbf == NULL) | (to_rbf == NULL)) {
708     fprintf(stderr,
709     "%s: bad DSF reference in migration edge\n",
710     progname);
711     return(0);
712     }
713     n = from_rbf->nrbf * to_rbf->nrbf;
714     newmig = (MIGRATION *)malloc(sizeof(MIGRATION) +
715     sizeof(float)*(n-1));
716     if (newmig == NULL)
717     goto memerr;
718     newmig->rbfv[0] = from_rbf;
719     newmig->rbfv[1] = to_rbf;
720 greg 2.2 memset(newmig->mtx, 0, sizeof(float)*n);
721     for (i = 0; ; ) { /* read sparse data */
722     int zc = getint(1, ifp) & 0xff;
723     if ((i += zc) >= n)
724     break;
725 greg 2.3 if (zc == 0xff)
726     continue;
727 greg 2.2 newmig->mtx[i++] = getflt(ifp);
728     }
729 greg 2.1 if (feof(ifp))
730     goto badEOF;
731     /* insert in edge lists */
732     newmig->enxt[0] = from_rbf->ejl;
733     from_rbf->ejl = newmig;
734     newmig->enxt[1] = to_rbf->ejl;
735     to_rbf->ejl = newmig;
736     /* push onto global list */
737     newmig->next = mig_list;
738     mig_list = newmig;
739     }
740     return(1); /* success! */
741     memerr:
742     fprintf(stderr, "%s: Out of memory in load_bsdf_rep()\n", progname);
743     exit(1);
744     badEOF:
745     fprintf(stderr, "%s: Unexpected EOF in load_bsdf_rep()\n", progname);
746     return(0);
747     }