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root/radiance/ray/src/cv/bsdfrep.c
Revision: 2.28
Committed: Thu May 28 15:46:28 2015 UTC (8 years, 11 months ago) by greg
Content type: text/plain
Branch: MAIN
CVS Tags: rad5R0
Changes since 2.27: +12 -11 lines
Log Message:
Put angle normalization before test that assumes it

File Contents

# User Rev Content
1 greg 2.1 #ifndef lint
2 greg 2.28 static const char RCSid[] = "$Id: bsdfrep.c,v 2.27 2014/08/22 05:38:44 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 2.26 double bsdf_spec_peak = 0;
38     double bsdf_spec_rad = 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     /* normalize angle ranges */
54     while (new_theta < -180.)
55     new_theta += 360.;
56     while (new_theta > 180.)
57     new_theta -= 360.;
58     if (new_theta < 0) {
59     new_theta = -new_theta;
60     new_phi += 180.;
61     }
62     while (new_phi < 0)
63     new_phi += 360.;
64     while (new_phi >= 360.)
65     new_phi -= 360.;
66 greg 2.28 /* check input orientation */
67     if (!input_orient)
68     input_orient = 1 - 2*(new_theta > 90.);
69     else if (input_orient > 0 ^ new_theta < 90.) {
70     fprintf(stderr,
71     "%s: Cannot handle input angles on both sides of surface\n",
72     progname);
73     return(0);
74     }
75     if ((theta_in_deg = new_theta) < 1.0)
76     return(1); /* don't rely on phi near normal */
77 greg 2.1 if (single_plane_incident > 0) /* check input coverage */
78     single_plane_incident = (round(new_phi) == round(phi_in_deg));
79     else if (single_plane_incident < 0)
80     single_plane_incident = 1;
81     phi_in_deg = new_phi;
82     if ((1. < new_phi) & (new_phi < 89.))
83     inp_coverage |= INP_QUAD1;
84     else if ((91. < new_phi) & (new_phi < 179.))
85     inp_coverage |= INP_QUAD2;
86     else if ((181. < new_phi) & (new_phi < 269.))
87     inp_coverage |= INP_QUAD3;
88     else if ((271. < new_phi) & (new_phi < 359.))
89     inp_coverage |= INP_QUAD4;
90     return(1);
91     }
92    
93     /* Apply symmetry to the given vector based on distribution */
94     int
95     use_symmetry(FVECT vec)
96     {
97 greg 2.11 const double phi = get_phi360(vec);
98 greg 2.1
99     switch (inp_coverage) {
100     case INP_QUAD1|INP_QUAD2|INP_QUAD3|INP_QUAD4:
101     break;
102     case INP_QUAD1|INP_QUAD2:
103     if ((-FTINY > phi) | (phi > 180.+FTINY))
104     goto mir_y;
105     break;
106     case INP_QUAD2|INP_QUAD3:
107     if ((90.-FTINY > phi) | (phi > 270.+FTINY))
108     goto mir_x;
109     break;
110     case INP_QUAD3|INP_QUAD4:
111     if ((180.-FTINY > phi) | (phi > 360.+FTINY))
112     goto mir_y;
113     break;
114     case INP_QUAD4|INP_QUAD1:
115     if ((270.-FTINY > phi) & (phi > 90.+FTINY))
116     goto mir_x;
117     break;
118     case INP_QUAD1:
119     if ((-FTINY > phi) | (phi > 90.+FTINY))
120     switch ((int)(phi*(1./90.))) {
121     case 1: goto mir_x;
122     case 2: goto mir_xy;
123     case 3: goto mir_y;
124     }
125     break;
126     case INP_QUAD2:
127     if ((90.-FTINY > phi) | (phi > 180.+FTINY))
128     switch ((int)(phi*(1./90.))) {
129     case 0: goto mir_x;
130     case 2: goto mir_y;
131     case 3: goto mir_xy;
132     }
133     break;
134     case INP_QUAD3:
135     if ((180.-FTINY > phi) | (phi > 270.+FTINY))
136     switch ((int)(phi*(1./90.))) {
137     case 0: goto mir_xy;
138     case 1: goto mir_y;
139     case 3: goto mir_x;
140     }
141     break;
142     case INP_QUAD4:
143     if ((270.-FTINY > phi) | (phi > 360.+FTINY))
144     switch ((int)(phi*(1./90.))) {
145     case 0: goto mir_y;
146     case 1: goto mir_xy;
147     case 2: goto mir_x;
148     }
149     break;
150     default:
151     fprintf(stderr, "%s: Illegal input coverage (%d)\n",
152     progname, inp_coverage);
153     exit(1);
154     }
155     return(0); /* in range */
156     mir_x:
157     vec[0] = -vec[0];
158     return(MIRROR_X);
159     mir_y:
160     vec[1] = -vec[1];
161     return(MIRROR_Y);
162     mir_xy:
163     vec[0] = -vec[0];
164     vec[1] = -vec[1];
165     return(MIRROR_X|MIRROR_Y);
166     }
167    
168     /* Reverse symmetry based on what was done before */
169     void
170     rev_symmetry(FVECT vec, int sym)
171     {
172     if (sym & MIRROR_X)
173     vec[0] = -vec[0];
174     if (sym & MIRROR_Y)
175     vec[1] = -vec[1];
176     }
177    
178     /* Reverse symmetry for an RBF distribution */
179     void
180     rev_rbf_symmetry(RBFNODE *rbf, int sym)
181     {
182     int n;
183    
184     rev_symmetry(rbf->invec, sym);
185     if (sym & MIRROR_X)
186     for (n = rbf->nrbf; n-- > 0; )
187 greg 2.5 rbf->rbfa[n].gx = grid_res-1 - rbf->rbfa[n].gx;
188 greg 2.1 if (sym & MIRROR_Y)
189     for (n = rbf->nrbf; n-- > 0; )
190 greg 2.5 rbf->rbfa[n].gy = grid_res-1 - rbf->rbfa[n].gy;
191 greg 2.1 }
192    
193 greg 2.6 /* Rotate RBF to correspond to given incident vector */
194     void
195     rotate_rbf(RBFNODE *rbf, const FVECT invec)
196     {
197     static const FVECT vnorm = {.0, .0, 1.};
198     const double phi = atan2(invec[1],invec[0]) -
199     atan2(rbf->invec[1],rbf->invec[0]);
200     FVECT outvec;
201     int pos[2];
202     int n;
203 greg 2.8
204 greg 2.24 for (n = (cos(phi) < 1.-FTINY)*rbf->nrbf; n-- > 0; ) {
205 greg 2.6 ovec_from_pos(outvec, rbf->rbfa[n].gx, rbf->rbfa[n].gy);
206     spinvector(outvec, outvec, vnorm, phi);
207     pos_from_vec(pos, outvec);
208     rbf->rbfa[n].gx = pos[0];
209     rbf->rbfa[n].gy = pos[1];
210     }
211     VCOPY(rbf->invec, invec);
212     }
213    
214 greg 2.1 /* Compute outgoing vector from grid position */
215     void
216     ovec_from_pos(FVECT vec, int xpos, int ypos)
217     {
218     double uv[2];
219     double r2;
220    
221 greg 2.8 SDsquare2disk(uv, (xpos+.5)/grid_res, (ypos+.5)/grid_res);
222 greg 2.1 /* uniform hemispherical projection */
223     r2 = uv[0]*uv[0] + uv[1]*uv[1];
224     vec[0] = vec[1] = sqrt(2. - r2);
225     vec[0] *= uv[0];
226     vec[1] *= uv[1];
227     vec[2] = output_orient*(1. - r2);
228     }
229    
230     /* Compute grid position from normalized input/output vector */
231     void
232     pos_from_vec(int pos[2], const FVECT vec)
233     {
234     double sq[2]; /* uniform hemispherical projection */
235     double norm = 1./sqrt(1. + fabs(vec[2]));
236    
237     SDdisk2square(sq, vec[0]*norm, vec[1]*norm);
238    
239 greg 2.5 pos[0] = (int)(sq[0]*grid_res);
240     pos[1] = (int)(sq[1]*grid_res);
241 greg 2.1 }
242    
243 greg 2.14 /* Compute volume associated with Gaussian lobe */
244     double
245     rbf_volume(const RBFVAL *rbfp)
246     {
247     double rad = R2ANG(rbfp->crad);
248     FVECT odir;
249     double elev, integ;
250     /* infinite integral approximation */
251     integ = (2.*M_PI) * rbfp->peak * rad*rad;
252     /* check if we're near horizon */
253     ovec_from_pos(odir, rbfp->gx, rbfp->gy);
254     elev = output_orient*odir[2];
255     /* apply cut-off correction if > 1% */
256     if (elev < 2.8*rad) {
257     /* elev = asin(elev); /* this is so crude, anyway... */
258     integ *= 1. - .5*exp(-.5*elev*elev/(rad*rad));
259     }
260     return(integ);
261     }
262    
263 greg 2.25 /* Evaluate BSDF at the given normalized outgoing direction */
264 greg 2.1 double
265     eval_rbfrep(const RBFNODE *rp, const FVECT outvec)
266     {
267 greg 2.17 const double rfact2 = (38./M_PI/M_PI)*(grid_res*grid_res);
268 greg 2.16 int pos[2];
269 greg 2.8 double res = 0;
270 greg 2.1 const RBFVAL *rbfp;
271     FVECT odir;
272 greg 2.16 double rad2;
273 greg 2.1 int n;
274 greg 2.14 /* check for wrong side */
275     if (outvec[2] > 0 ^ output_orient > 0)
276     return(.0);
277 greg 2.12 /* use minimum if no information avail. */
278 greg 2.14 if (rp == NULL)
279 greg 2.25 return(bsdf_min);
280 greg 2.16 /* optimization for fast lobe culling */
281     pos_from_vec(pos, outvec);
282 greg 2.14 /* sum radial basis function */
283 greg 2.1 rbfp = rp->rbfa;
284     for (n = rp->nrbf; n--; rbfp++) {
285 greg 2.16 int d2 = (pos[0]-rbfp->gx)*(pos[0]-rbfp->gx) +
286     (pos[1]-rbfp->gy)*(pos[1]-rbfp->gy);
287     rad2 = R2ANG(rbfp->crad);
288     rad2 *= rad2;
289 greg 2.17 if (d2 > rad2*rfact2)
290 greg 2.16 continue;
291 greg 2.1 ovec_from_pos(odir, rbfp->gx, rbfp->gy);
292 greg 2.16 res += rbfp->peak * exp((DOT(odir,outvec) - 1.) / rad2);
293 greg 2.1 }
294 greg 2.27 res /= COSF(outvec[2]);
295 greg 2.25 if (res < bsdf_min) /* never return less than bsdf_min */
296     return(bsdf_min);
297 greg 2.1 return(res);
298     }
299    
300     /* Insert a new directional scattering function in our global list */
301     int
302     insert_dsf(RBFNODE *newrbf)
303     {
304     RBFNODE *rbf, *rbf_last;
305     int pos;
306     /* check for redundant meas. */
307     for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
308     if (DOT(rbf->invec, newrbf->invec) >= 1.-FTINY) {
309     fprintf(stderr,
310 greg 2.22 "%s: Duplicate incident measurement ignored at (%.1f,%.1f)\n",
311     progname, get_theta180(newrbf->invec),
312     get_phi360(newrbf->invec));
313 greg 2.1 free(newrbf);
314     return(-1);
315     }
316     /* keep in ascending theta order */
317     for (rbf_last = NULL, rbf = dsf_list; rbf != NULL;
318     rbf_last = rbf, rbf = rbf->next)
319     if (single_plane_incident && input_orient*rbf->invec[2] <
320     input_orient*newrbf->invec[2])
321     break;
322     if (rbf_last == NULL) { /* insert new node in list */
323     newrbf->ord = 0;
324     newrbf->next = dsf_list;
325     dsf_list = newrbf;
326     } else {
327     newrbf->ord = rbf_last->ord + 1;
328     newrbf->next = rbf;
329     rbf_last->next = newrbf;
330     }
331     rbf_last = newrbf;
332     while (rbf != NULL) { /* update ordinal positions */
333     rbf->ord = rbf_last->ord + 1;
334     rbf_last = rbf;
335     rbf = rbf->next;
336     }
337     return(newrbf->ord);
338     }
339    
340     /* Get the DSF indicated by its ordinal position */
341     RBFNODE *
342     get_dsf(int ord)
343     {
344     RBFNODE *rbf;
345    
346     for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
347 greg 2.3 if (rbf->ord == ord)
348 greg 2.1 return(rbf);
349     return(NULL);
350     }
351    
352     /* Get triangle surface orientation (unnormalized) */
353     void
354     tri_orient(FVECT vres, const FVECT v1, const FVECT v2, const FVECT v3)
355     {
356     FVECT v2minus1, v3minus2;
357    
358     VSUB(v2minus1, v2, v1);
359     VSUB(v3minus2, v3, v2);
360     VCROSS(vres, v2minus1, v3minus2);
361     }
362    
363     /* Determine if vertex order is reversed (inward normal) */
364     int
365     is_rev_tri(const FVECT v1, const FVECT v2, const FVECT v3)
366     {
367     FVECT tor;
368    
369     tri_orient(tor, v1, v2, v3);
370    
371     return(DOT(tor, v2) < 0.);
372     }
373    
374     /* Find vertices completing triangles on either side of the given edge */
375     int
376     get_triangles(RBFNODE *rbfv[2], const MIGRATION *mig)
377     {
378 greg 2.4 const MIGRATION *ej1, *ej2;
379 greg 2.1 RBFNODE *tv;
380    
381     rbfv[0] = rbfv[1] = NULL;
382     if (mig == NULL)
383     return(0);
384 greg 2.4 for (ej1 = mig->rbfv[0]->ejl; ej1 != NULL;
385     ej1 = nextedge(mig->rbfv[0],ej1)) {
386     if (ej1 == mig)
387 greg 2.1 continue;
388 greg 2.4 tv = opp_rbf(mig->rbfv[0],ej1);
389 greg 2.1 for (ej2 = tv->ejl; ej2 != NULL; ej2 = nextedge(tv,ej2))
390     if (opp_rbf(tv,ej2) == mig->rbfv[1]) {
391     rbfv[is_rev_tri(mig->rbfv[0]->invec,
392     mig->rbfv[1]->invec,
393     tv->invec)] = tv;
394     break;
395     }
396     }
397     return((rbfv[0] != NULL) + (rbfv[1] != NULL));
398     }
399    
400 greg 2.25 /* Return single-lobe specular RBF for the given incident direction */
401     RBFNODE *
402     def_rbf_spec(const FVECT invec)
403     {
404     RBFNODE *rbf;
405     FVECT ovec;
406     int pos[2];
407    
408     if (input_orient > 0 ^ invec[2] > 0) /* wrong side? */
409     return(NULL);
410 greg 2.26 if ((bsdf_spec_peak <= bsdf_min) | (bsdf_spec_rad <= 0))
411 greg 2.25 return(NULL); /* nothing set */
412     rbf = (RBFNODE *)malloc(sizeof(RBFNODE));
413     if (rbf == NULL)
414     return(NULL);
415     ovec[0] = -invec[0];
416     ovec[1] = -invec[1];
417     ovec[2] = invec[2]*(2*(input_orient==output_orient) - 1);
418     pos_from_vec(pos, ovec);
419     rbf->ord = 0;
420     rbf->next = NULL;
421     rbf->ejl = NULL;
422     VCOPY(rbf->invec, invec);
423     rbf->nrbf = 1;
424     rbf->rbfa[0].peak = bsdf_spec_peak * output_orient*ovec[2];
425 greg 2.26 rbf->rbfa[0].crad = ANG2R(bsdf_spec_rad);
426 greg 2.25 rbf->rbfa[0].gx = pos[0];
427     rbf->rbfa[0].gy = pos[1];
428     rbf->vtotal = rbf_volume(rbf->rbfa);
429     return(rbf);
430     }
431    
432 greg 2.20 /* Advect and allocate new RBF along edge (internal call) */
433     RBFNODE *
434     e_advect_rbf(const MIGRATION *mig, const FVECT invec, int lobe_lim)
435     {
436     double cthresh = FTINY;
437     RBFNODE *rbf;
438     int n, i, j;
439     double t, full_dist;
440     /* get relative position */
441     t = Acos(DOT(invec, mig->rbfv[0]->invec));
442     if (t < M_PI/grid_res) { /* near first DSF */
443     n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[0]->nrbf-1);
444     rbf = (RBFNODE *)malloc(n);
445     if (rbf == NULL)
446     goto memerr;
447     memcpy(rbf, mig->rbfv[0], n); /* just duplicate */
448     rbf->next = NULL; rbf->ejl = NULL;
449     return(rbf);
450     }
451     full_dist = acos(DOT(mig->rbfv[0]->invec, mig->rbfv[1]->invec));
452     if (t > full_dist-M_PI/grid_res) { /* near second DSF */
453     n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[1]->nrbf-1);
454     rbf = (RBFNODE *)malloc(n);
455     if (rbf == NULL)
456     goto memerr;
457     memcpy(rbf, mig->rbfv[1], n); /* just duplicate */
458     rbf->next = NULL; rbf->ejl = NULL;
459     return(rbf);
460     }
461     t /= full_dist;
462     tryagain:
463     n = 0; /* count migrating particles */
464     for (i = 0; i < mtx_nrows(mig); i++)
465     for (j = 0; j < mtx_ncols(mig); j++)
466     n += (mtx_coef(mig,i,j) > cthresh);
467     /* are we over our limit? */
468     if ((lobe_lim > 0) & (n > lobe_lim)) {
469     cthresh = cthresh*2. + 10.*FTINY;
470     goto tryagain;
471     }
472     #ifdef DEBUG
473     fprintf(stderr, "Input RBFs have %d, %d nodes -> output has %d\n",
474     mig->rbfv[0]->nrbf, mig->rbfv[1]->nrbf, n);
475     #endif
476     rbf = (RBFNODE *)malloc(sizeof(RBFNODE) + sizeof(RBFVAL)*(n-1));
477     if (rbf == NULL)
478     goto memerr;
479     rbf->next = NULL; rbf->ejl = NULL;
480     VCOPY(rbf->invec, invec);
481     rbf->nrbf = n;
482     rbf->vtotal = 1.-t + t*mig->rbfv[1]->vtotal/mig->rbfv[0]->vtotal;
483     n = 0; /* advect RBF lobes */
484     for (i = 0; i < mtx_nrows(mig); i++) {
485     const RBFVAL *rbf0i = &mig->rbfv[0]->rbfa[i];
486     const float peak0 = rbf0i->peak;
487     const double rad0 = R2ANG(rbf0i->crad);
488     FVECT v0;
489     float mv;
490     ovec_from_pos(v0, rbf0i->gx, rbf0i->gy);
491     for (j = 0; j < mtx_ncols(mig); j++)
492     if ((mv = mtx_coef(mig,i,j)) > cthresh) {
493     const RBFVAL *rbf1j = &mig->rbfv[1]->rbfa[j];
494     double rad2;
495     FVECT v;
496     int pos[2];
497     rad2 = R2ANG(rbf1j->crad);
498     rad2 = rad0*rad0*(1.-t) + rad2*rad2*t;
499     rbf->rbfa[n].peak = peak0 * mv * rbf->vtotal *
500     rad0*rad0/rad2;
501     rbf->rbfa[n].crad = ANG2R(sqrt(rad2));
502     ovec_from_pos(v, rbf1j->gx, rbf1j->gy);
503     geodesic(v, v0, v, t, GEOD_REL);
504     pos_from_vec(pos, v);
505     rbf->rbfa[n].gx = pos[0];
506     rbf->rbfa[n].gy = pos[1];
507     ++n;
508     }
509     }
510     rbf->vtotal *= mig->rbfv[0]->vtotal; /* turn ratio into actual */
511     return(rbf);
512     memerr:
513     fprintf(stderr, "%s: Out of memory in e_advect_rbf()\n", progname);
514     exit(1);
515     return(NULL); /* pro forma return */
516     }
517    
518 greg 2.4 /* Clear our BSDF representation and free memory */
519     void
520     clear_bsdf_rep(void)
521     {
522     while (mig_list != NULL) {
523     MIGRATION *mig = mig_list;
524     mig_list = mig->next;
525     free(mig);
526     }
527     while (dsf_list != NULL) {
528     RBFNODE *rbf = dsf_list;
529     dsf_list = rbf->next;
530     free(rbf);
531     }
532 greg 2.19 bsdf_name[0] = '\0';
533     bsdf_manuf[0] = '\0';
534 greg 2.4 inp_coverage = 0;
535     single_plane_incident = -1;
536     input_orient = output_orient = 0;
537 greg 2.5 grid_res = GRIDRES;
538 greg 2.25 bsdf_min = 0;
539     bsdf_spec_peak = 0;
540 greg 2.26 bsdf_spec_rad = 0;
541 greg 2.4 }
542    
543 greg 2.1 /* Write our BSDF mesh interpolant out to the given binary stream */
544     void
545     save_bsdf_rep(FILE *ofp)
546     {
547     RBFNODE *rbf;
548     MIGRATION *mig;
549     int i, n;
550     /* finish header */
551 greg 2.19 if (bsdf_name[0])
552     fprintf(ofp, "NAME=%s\n", bsdf_name);
553     if (bsdf_manuf[0])
554     fprintf(ofp, "MANUFACT=%s\n", bsdf_manuf);
555 greg 2.2 fprintf(ofp, "SYMMETRY=%d\n", !single_plane_incident * inp_coverage);
556     fprintf(ofp, "IO_SIDES= %d %d\n", input_orient, output_orient);
557 greg 2.5 fprintf(ofp, "GRIDRES=%d\n", grid_res);
558 greg 2.12 fprintf(ofp, "BSDFMIN=%g\n", bsdf_min);
559 greg 2.26 if ((bsdf_spec_peak > bsdf_min) & (bsdf_spec_rad > 0))
560     fprintf(ofp, "BSDFSPEC= %f %f\n", bsdf_spec_peak, bsdf_spec_rad);
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 greg 2.26 sscanf(s+9, "%lf %lf", &bsdf_spec_peak, &bsdf_spec_rad);
640 greg 2.25 return(0);
641     }
642 greg 2.2 if (formatval(fmt, s) && strcmp(fmt, BSDFREP_FMT))
643     return(-1);
644     return(0);
645     }
646    
647 greg 2.1 /* Read a BSDF mesh interpolant from the given binary stream */
648     int
649     load_bsdf_rep(FILE *ifp)
650     {
651     RBFNODE rbfh;
652     int from_ord, to_ord;
653     int i;
654 greg 2.4
655     clear_bsdf_rep();
656 greg 2.5 if (ifp == NULL)
657     return(0);
658 greg 2.21 if (getheader(ifp, headline, NULL) < 0 || (single_plane_incident < 0) |
659 greg 2.23 !input_orient | !output_orient |
660     (grid_res < 16) | (grid_res > 256)) {
661 greg 2.1 fprintf(stderr, "%s: missing/bad format for BSDF interpolant\n",
662     progname);
663     return(0);
664     }
665 greg 2.18 memset(&rbfh, 0, sizeof(rbfh)); /* read each DSF */
666 greg 2.1 while ((rbfh.ord = getint(4, ifp)) >= 0) {
667     RBFNODE *newrbf;
668    
669     rbfh.invec[0] = getflt(ifp);
670     rbfh.invec[1] = getflt(ifp);
671     rbfh.invec[2] = getflt(ifp);
672 greg 2.9 if (normalize(rbfh.invec) == 0) {
673     fprintf(stderr, "%s: zero incident vector\n", progname);
674     return(0);
675     }
676 greg 2.3 rbfh.vtotal = getflt(ifp);
677 greg 2.1 rbfh.nrbf = getint(4, ifp);
678     newrbf = (RBFNODE *)malloc(sizeof(RBFNODE) +
679     sizeof(RBFVAL)*(rbfh.nrbf-1));
680     if (newrbf == NULL)
681     goto memerr;
682 greg 2.18 *newrbf = rbfh;
683 greg 2.1 for (i = 0; i < rbfh.nrbf; i++) {
684     newrbf->rbfa[i].peak = getflt(ifp);
685     newrbf->rbfa[i].crad = getint(2, ifp) & 0xffff;
686     newrbf->rbfa[i].gx = getint(1, ifp) & 0xff;
687     newrbf->rbfa[i].gy = getint(1, ifp) & 0xff;
688     }
689     if (feof(ifp))
690     goto badEOF;
691     /* insert in global list */
692     if (insert_dsf(newrbf) != rbfh.ord) {
693     fprintf(stderr, "%s: error adding DSF\n", progname);
694     return(0);
695     }
696     }
697     /* read each migration matrix */
698     while ((from_ord = getint(4, ifp)) >= 0 &&
699     (to_ord = getint(4, ifp)) >= 0) {
700     RBFNODE *from_rbf = get_dsf(from_ord);
701     RBFNODE *to_rbf = get_dsf(to_ord);
702     MIGRATION *newmig;
703     int n;
704    
705     if ((from_rbf == NULL) | (to_rbf == NULL)) {
706     fprintf(stderr,
707     "%s: bad DSF reference in migration edge\n",
708     progname);
709     return(0);
710     }
711     n = from_rbf->nrbf * to_rbf->nrbf;
712     newmig = (MIGRATION *)malloc(sizeof(MIGRATION) +
713     sizeof(float)*(n-1));
714     if (newmig == NULL)
715     goto memerr;
716     newmig->rbfv[0] = from_rbf;
717     newmig->rbfv[1] = to_rbf;
718 greg 2.2 memset(newmig->mtx, 0, sizeof(float)*n);
719     for (i = 0; ; ) { /* read sparse data */
720     int zc = getint(1, ifp) & 0xff;
721     if ((i += zc) >= n)
722     break;
723 greg 2.3 if (zc == 0xff)
724     continue;
725 greg 2.2 newmig->mtx[i++] = getflt(ifp);
726     }
727 greg 2.1 if (feof(ifp))
728     goto badEOF;
729     /* insert in edge lists */
730     newmig->enxt[0] = from_rbf->ejl;
731     from_rbf->ejl = newmig;
732     newmig->enxt[1] = to_rbf->ejl;
733     to_rbf->ejl = newmig;
734     /* push onto global list */
735     newmig->next = mig_list;
736     mig_list = newmig;
737     }
738     return(1); /* success! */
739     memerr:
740     fprintf(stderr, "%s: Out of memory in load_bsdf_rep()\n", progname);
741     exit(1);
742     badEOF:
743     fprintf(stderr, "%s: Unexpected EOF in load_bsdf_rep()\n", progname);
744     return(0);
745     }