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root/radiance/ray/src/common/image.c
Revision: 2.42
Committed: Wed Jan 24 04:23:06 2018 UTC (6 years, 3 months ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.41: +12 -11 lines
Log Message:
Tweaked viewloc() return value so 1 is in front, -1 is behind and 0 is error

File Contents

# Content
1 #ifndef lint
2 static const char RCSid[] = "$Id: image.c,v 2.41 2018/01/24 03:34:15 greg Exp $";
3 #endif
4 /*
5 * image.c - routines for image generation.
6 *
7 * External symbols declared in view.h
8 */
9
10 #include "copyright.h"
11
12 #include <ctype.h>
13 #include "rtio.h"
14 #include "rtmath.h"
15 #include "paths.h"
16 #include "view.h"
17
18
19 #define FEQ(x,y) (fabs((x)-(y)) <= FTINY)
20 #define VEQ(v,w) (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
21 && FEQ((v)[2],(w)[2]))
22
23 VIEW stdview = STDVIEW; /* default view parameters */
24
25 static gethfunc gethview;
26
27
28 char *
29 setview( /* set hvec and vvec, return message on error */
30 VIEW *v
31 )
32 {
33 static char ill_horiz[] = "illegal horizontal view size";
34 static char ill_vert[] = "illegal vertical view size";
35
36 if ((v->vfore < -FTINY) | (v->vaft < -FTINY) ||
37 (v->vaft > FTINY) & (v->vaft <= v->vfore))
38 return("illegal fore/aft clipping plane");
39
40 if (v->vdist <= FTINY)
41 return("illegal view distance");
42 v->vdist *= normalize(v->vdir); /* normalize direction */
43 if (v->vdist == 0.0)
44 return("zero view direction");
45
46 if (normalize(v->vup) == 0.0) /* normalize view up */
47 return("zero view up vector");
48
49 fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
50
51 if (normalize(v->hvec) == 0.0)
52 return("view up parallel to view direction");
53
54 fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
55
56 if (v->horiz <= FTINY)
57 return(ill_horiz);
58 if (v->vert <= FTINY)
59 return(ill_vert);
60
61 switch (v->type) {
62 case VT_PAR: /* parallel view */
63 v->hn2 = v->horiz;
64 v->vn2 = v->vert;
65 break;
66 case VT_PER: /* perspective view */
67 if (v->horiz >= 180.0-FTINY)
68 return(ill_horiz);
69 if (v->vert >= 180.0-FTINY)
70 return(ill_vert);
71 v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
72 v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
73 break;
74 case VT_CYL: /* cylindrical panorama */
75 if (v->horiz > 360.0+FTINY)
76 return(ill_horiz);
77 if (v->vert >= 180.0-FTINY)
78 return(ill_vert);
79 v->hn2 = v->horiz * (PI/180.0);
80 v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
81 break;
82 case VT_ANG: /* angular fisheye */
83 if (v->horiz > 360.0+FTINY)
84 return(ill_horiz);
85 if (v->vert > 360.0+FTINY)
86 return(ill_vert);
87 v->hn2 = v->horiz * (PI/180.0);
88 v->vn2 = v->vert * (PI/180.0);
89 break;
90 case VT_HEM: /* hemispherical fisheye */
91 if (v->horiz > 180.0+FTINY)
92 return(ill_horiz);
93 if (v->vert > 180.0+FTINY)
94 return(ill_vert);
95 v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
96 v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
97 break;
98 case VT_PLS: /* planispheric fisheye */
99 if (v->horiz >= 360.0-FTINY)
100 return(ill_horiz);
101 if (v->vert >= 360.0-FTINY)
102 return(ill_vert);
103 v->hn2 = 2.*sin(v->horiz*(PI/180.0/2.0)) /
104 (1.0 + cos(v->horiz*(PI/180.0/2.0)));
105 v->vn2 = 2.*sin(v->vert*(PI/180.0/2.0)) /
106 (1.0 + cos(v->vert*(PI/180.0/2.0)));
107 break;
108 default:
109 return("unknown view type");
110 }
111 if (v->type != VT_ANG && v->type != VT_PLS) {
112 if (v->type != VT_CYL) {
113 v->hvec[0] *= v->hn2;
114 v->hvec[1] *= v->hn2;
115 v->hvec[2] *= v->hn2;
116 }
117 v->vvec[0] *= v->vn2;
118 v->vvec[1] *= v->vn2;
119 v->vvec[2] *= v->vn2;
120 }
121 v->hn2 *= v->hn2;
122 v->vn2 *= v->vn2;
123
124 return(NULL);
125 }
126
127
128 void
129 normaspect( /* fix pixel aspect or resolution */
130 double va, /* view aspect ratio */
131 double *ap, /* pixel aspect in (or out if 0) */
132 int *xp,
133 int *yp /* x and y resolution in (or out if *ap!=0) */
134 )
135 {
136 if (*ap <= FTINY)
137 *ap = va * *xp / *yp; /* compute pixel aspect */
138 else if (va * *xp > *ap * *yp)
139 *xp = *yp / va * *ap + .5; /* reduce x resolution */
140 else
141 *yp = *xp * va / *ap + .5; /* reduce y resolution */
142 }
143
144
145 double
146 viewray( /* compute ray origin and direction */
147 FVECT orig,
148 FVECT direc,
149 VIEW *v,
150 double x,
151 double y
152 )
153 {
154 double d, z;
155
156 x += v->hoff - 0.5;
157 y += v->voff - 0.5;
158
159 switch(v->type) {
160 case VT_PAR: /* parallel view */
161 orig[0] = v->vp[0] + v->vfore*v->vdir[0]
162 + x*v->hvec[0] + y*v->vvec[0];
163 orig[1] = v->vp[1] + v->vfore*v->vdir[1]
164 + x*v->hvec[1] + y*v->vvec[1];
165 orig[2] = v->vp[2] + v->vfore*v->vdir[2]
166 + x*v->hvec[2] + y*v->vvec[2];
167 VCOPY(direc, v->vdir);
168 return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
169 case VT_PER: /* perspective view */
170 direc[0] = v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
171 direc[1] = v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
172 direc[2] = v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
173 VSUM(orig, v->vp, direc, v->vfore);
174 d = normalize(direc);
175 return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
176 case VT_HEM: /* hemispherical fisheye */
177 z = 1.0 - x*x*v->hn2 - y*y*v->vn2;
178 if (z < 0.0)
179 return(-1.0);
180 z = sqrt(z);
181 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
182 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
183 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
184 VSUM(orig, v->vp, direc, v->vfore);
185 return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
186 case VT_CYL: /* cylindrical panorama */
187 d = x * v->horiz * (PI/180.0);
188 z = cos(d);
189 x = sin(d);
190 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
191 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
192 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
193 VSUM(orig, v->vp, direc, v->vfore);
194 d = normalize(direc);
195 return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
196 case VT_ANG: /* angular fisheye */
197 x *= (1.0/180.0)*v->horiz;
198 y *= (1.0/180.0)*v->vert;
199 d = x*x + y*y;
200 if (d > 1.0)
201 return(-1.0);
202 d = sqrt(d);
203 z = cos(PI*d);
204 d = d <= FTINY ? PI : sqrt(1.0 - z*z)/d;
205 x *= d;
206 y *= d;
207 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
208 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
209 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
210 VSUM(orig, v->vp, direc, v->vfore);
211 return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
212 case VT_PLS: /* planispheric fisheye */
213 x *= sqrt(v->hn2);
214 y *= sqrt(v->vn2);
215 d = x*x + y*y;
216 z = (1. - d)/(1. + d);
217 x *= (1. + z);
218 y *= (1. + z);
219 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
220 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
221 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
222 VSUM(orig, v->vp, direc, v->vfore);
223 return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
224 }
225 return(-1.0);
226 }
227
228
229 int
230 viewloc( /* find image location for point */
231 FVECT ip,
232 VIEW *v,
233 FVECT p
234 )
235 {
236 double d, d2;
237 FVECT disp;
238
239 VSUB(disp, p, v->vp);
240
241 switch (v->type) {
242 case VT_PAR: /* parallel view */
243 ip[2] = DOT(disp,v->vdir) - v->vfore;
244 break;
245 case VT_PER: /* perspective view */
246 d = DOT(disp,v->vdir);
247 ip[2] = VLEN(disp);
248 if (d < -FTINY) { /* fold pyramid */
249 ip[2] = -ip[2];
250 d = -d;
251 } else if (d <= FTINY)
252 return(0); /* at infinite edge */
253 d = 1.0/d;
254 disp[0] *= d;
255 disp[1] *= d;
256 disp[2] *= d;
257 if (ip[2] < 0.0) d = -d;
258 ip[2] *= (1.0 - v->vfore*d);
259 break;
260 case VT_HEM: /* hemispherical fisheye */
261 d = normalize(disp);
262 if (DOT(disp,v->vdir) < 0.0)
263 ip[2] = -d;
264 else
265 ip[2] = d;
266 ip[2] -= v->vfore;
267 break;
268 case VT_CYL: /* cylindrical panorama */
269 d = DOT(disp,v->hvec);
270 d2 = DOT(disp,v->vdir);
271 ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
272 d = d*d + d2*d2;
273 if (d <= FTINY*FTINY)
274 return(0); /* at pole */
275 d = 1.0/sqrt(d);
276 ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
277 ip[2] = VLEN(disp);
278 ip[2] *= (1.0 - v->vfore*d);
279 goto gotall;
280 case VT_ANG: /* angular fisheye */
281 ip[0] = 0.5 - v->hoff;
282 ip[1] = 0.5 - v->voff;
283 ip[2] = normalize(disp) - v->vfore;
284 d = DOT(disp,v->vdir);
285 if (d >= 1.0-FTINY)
286 goto gotall;
287 if (d <= -(1.0-FTINY)) {
288 ip[0] += 180.0/v->horiz;
289 goto gotall;
290 }
291 d = (180.0/PI)*acos(d) / sqrt(1.0 - d*d);
292 ip[0] += DOT(disp,v->hvec)*d/v->horiz;
293 ip[1] += DOT(disp,v->vvec)*d/v->vert;
294 goto gotall;
295 case VT_PLS: /* planispheric fisheye */
296 ip[0] = 0.5 - v->hoff;
297 ip[1] = 0.5 - v->voff;
298 ip[2] = normalize(disp) - v->vfore;
299 d = DOT(disp,v->vdir);
300 if (d >= 1.0-FTINY)
301 goto gotall;
302 if (d <= -(1.0-FTINY))
303 return(0);
304 ip[0] += DOT(disp,v->hvec)/((1. + d)*sqrt(v->hn2));
305 ip[1] += DOT(disp,v->vvec)/((1. + d)*sqrt(v->vn2));
306 goto gotall;
307 }
308 ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
309 ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
310 gotall: /* return -1 if behind */
311 return(1 - 2*(ip[2] <= 0.0));
312 }
313
314
315 void
316 pix2loc( /* compute image location from pixel pos. */
317 RREAL loc[2],
318 RESOLU *rp,
319 int px,
320 int py
321 )
322 {
323 int x, y;
324
325 if (rp->rt & YMAJOR) {
326 x = px;
327 y = py;
328 } else {
329 x = py;
330 y = px;
331 }
332 if (rp->rt & XDECR)
333 x = rp->xr-1 - x;
334 if (rp->rt & YDECR)
335 y = rp->yr-1 - y;
336 loc[0] = (x+.5)/rp->xr;
337 loc[1] = (y+.5)/rp->yr;
338 }
339
340
341 void
342 loc2pix( /* compute pixel pos. from image location */
343 int pp[2],
344 RESOLU *rp,
345 double lx,
346 double ly
347 )
348 {
349 int x, y;
350
351 x = (int)(lx*rp->xr + .5 - (lx < 0.0));
352 y = (int)(ly*rp->yr + .5 - (ly < 0.0));
353
354 if (rp->rt & XDECR)
355 x = rp->xr-1 - x;
356 if (rp->rt & YDECR)
357 y = rp->yr-1 - y;
358 if (rp->rt & YMAJOR) {
359 pp[0] = x;
360 pp[1] = y;
361 } else {
362 pp[0] = y;
363 pp[1] = x;
364 }
365 }
366
367
368 int
369 getviewopt( /* process view argument */
370 VIEW *v,
371 int ac,
372 char *av[]
373 )
374 {
375 #define check(c,l) if ((av[0][c]&&av[0][c]!=' ') || \
376 badarg(ac-1,av+1,l)) return(-1)
377
378 if (ac <= 0 || av[0][0] != '-' || av[0][1] != 'v')
379 return(-1);
380 switch (av[0][2]) {
381 case 't': /* type */
382 if (!av[0][3] || av[0][3]==' ')
383 return(-1);
384 check(4,"");
385 v->type = av[0][3];
386 return(0);
387 case 'p': /* point */
388 check(3,"fff");
389 v->vp[0] = atof(av[1]);
390 v->vp[1] = atof(av[2]);
391 v->vp[2] = atof(av[3]);
392 return(3);
393 case 'd': /* direction */
394 check(3,"fff");
395 v->vdir[0] = atof(av[1]);
396 v->vdir[1] = atof(av[2]);
397 v->vdir[2] = atof(av[3]);
398 v->vdist = 1.;
399 return(3);
400 case 'u': /* up */
401 check(3,"fff");
402 v->vup[0] = atof(av[1]);
403 v->vup[1] = atof(av[2]);
404 v->vup[2] = atof(av[3]);
405 return(3);
406 case 'h': /* horizontal size */
407 check(3,"f");
408 v->horiz = atof(av[1]);
409 return(1);
410 case 'v': /* vertical size */
411 check(3,"f");
412 v->vert = atof(av[1]);
413 return(1);
414 case 'o': /* fore clipping plane */
415 check(3,"f");
416 v->vfore = atof(av[1]);
417 return(1);
418 case 'a': /* aft clipping plane */
419 check(3,"f");
420 v->vaft = atof(av[1]);
421 return(1);
422 case 's': /* shift */
423 check(3,"f");
424 v->hoff = atof(av[1]);
425 return(1);
426 case 'l': /* lift */
427 check(3,"f");
428 v->voff = atof(av[1]);
429 return(1);
430 default:
431 return(-1);
432 }
433 #undef check
434 }
435
436
437 int
438 sscanview( /* get view parameters from string */
439 VIEW *vp,
440 char *s
441 )
442 {
443 int ac;
444 char *av[4];
445 int na;
446 int nvopts = 0;
447
448 while (isspace(*s))
449 if (!*s++)
450 return(0);
451 while (*s) {
452 ac = 0;
453 do {
454 if (ac || *s == '-')
455 av[ac++] = s;
456 while (*s && !isspace(*s))
457 s++;
458 while (isspace(*s))
459 s++;
460 } while (*s && ac < 4);
461 if ((na = getviewopt(vp, ac, av)) >= 0) {
462 if (na+1 < ac)
463 s = av[na+1];
464 nvopts++;
465 } else if (ac > 1)
466 s = av[1];
467 }
468 return(nvopts);
469 }
470
471
472 void
473 fprintview( /* write out view parameters */
474 VIEW *vp,
475 FILE *fp
476 )
477 {
478 fprintf(fp, " -vt%c", vp->type);
479 fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
480 fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0]*vp->vdist,
481 vp->vdir[1]*vp->vdist,
482 vp->vdir[2]*vp->vdist);
483 fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
484 fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
485 fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
486 fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
487 }
488
489
490 char *
491 viewopt( /* translate to minimal view string */
492 VIEW *vp
493 )
494 {
495 static char vwstr[128];
496 char *cp = vwstr;
497
498 *cp = '\0';
499 if (vp->type != stdview.type) {
500 sprintf(cp, " -vt%c", vp->type);
501 cp += strlen(cp);
502 }
503 if (!VEQ(vp->vp,stdview.vp)) {
504 sprintf(cp, " -vp %.6g %.6g %.6g",
505 vp->vp[0], vp->vp[1], vp->vp[2]);
506 cp += strlen(cp);
507 }
508 if (!FEQ(vp->vdist,stdview.vdist) || !VEQ(vp->vdir,stdview.vdir)) {
509 sprintf(cp, " -vd %.6g %.6g %.6g",
510 vp->vdir[0]*vp->vdist,
511 vp->vdir[1]*vp->vdist,
512 vp->vdir[2]*vp->vdist);
513 cp += strlen(cp);
514 }
515 if (!VEQ(vp->vup,stdview.vup)) {
516 sprintf(cp, " -vu %.6g %.6g %.6g",
517 vp->vup[0], vp->vup[1], vp->vup[2]);
518 cp += strlen(cp);
519 }
520 if (!FEQ(vp->horiz,stdview.horiz)) {
521 sprintf(cp, " -vh %.6g", vp->horiz);
522 cp += strlen(cp);
523 }
524 if (!FEQ(vp->vert,stdview.vert)) {
525 sprintf(cp, " -vv %.6g", vp->vert);
526 cp += strlen(cp);
527 }
528 if (!FEQ(vp->vfore,stdview.vfore)) {
529 sprintf(cp, " -vo %.6g", vp->vfore);
530 cp += strlen(cp);
531 }
532 if (!FEQ(vp->vaft,stdview.vaft)) {
533 sprintf(cp, " -va %.6g", vp->vaft);
534 cp += strlen(cp);
535 }
536 if (!FEQ(vp->hoff,stdview.hoff)) {
537 sprintf(cp, " -vs %.6g", vp->hoff);
538 cp += strlen(cp);
539 }
540 if (!FEQ(vp->voff,stdview.voff)) {
541 sprintf(cp, " -vl %.6g", vp->voff);
542 cp += strlen(cp);
543 }
544 return(vwstr);
545 }
546
547
548 int
549 isview( /* is this a view string? */
550 char *s
551 )
552 {
553 static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
554 extern char *progname;
555 char *cp;
556 char **an;
557 /* add program name to list */
558 if (altname[0] == NULL) {
559 for (cp = progname; *cp; cp++)
560 ;
561 while (cp > progname && !ISDIRSEP(cp[-1]))
562 cp--;
563 altname[0] = cp;
564 }
565 /* skip leading path */
566 cp = s;
567 while (*cp && *cp != ' ')
568 cp++;
569 while (cp > s && !ISDIRSEP(cp[-1]))
570 cp--;
571 for (an = altname; *an != NULL; an++)
572 if (!strncmp(*an, cp, strlen(*an)))
573 return(1);
574 return(0);
575 }
576
577
578 struct myview {
579 VIEW *hv;
580 int ok;
581 };
582
583
584 static int
585 gethview( /* get view from header */
586 char *s,
587 void *v
588 )
589 {
590 if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
591 ((struct myview*)v)->ok++;
592 return(0);
593 }
594
595
596 int
597 viewfile( /* get view from file */
598 char *fname,
599 VIEW *vp,
600 RESOLU *rp
601 )
602 {
603 struct myview mvs;
604 FILE *fp;
605
606 if (fname == NULL || !strcmp(fname, "-"))
607 fp = stdin;
608 else if ((fp = fopen(fname, "r")) == NULL)
609 return(-1);
610
611 mvs.hv = vp;
612 mvs.ok = 0;
613
614 getheader(fp, gethview, &mvs);
615
616 if (rp != NULL && !fgetsresolu(rp, fp))
617 mvs.ok = 0;
618
619 fclose(fp);
620
621 return(mvs.ok);
622 }