ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/ray/src/common/image.c
Revision: 2.3
Committed: Tue Apr 28 09:36:42 1992 UTC (32 years ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.2: +30 -13 lines
Log Message:
added isview() call

File Contents

# Content
1 /* Copyright (c) 1991 Regents of the University of California */
2
3 #ifndef lint
4 static char SCCSid[] = "$SunId$ LBL";
5 #endif
6
7 /*
8 * image.c - routines for image generation.
9 *
10 * 10/17/85
11 */
12
13 #include "standard.h"
14
15 #include "view.h"
16
17 #include "resolu.h"
18
19 VIEW stdview = STDVIEW; /* default view parameters */
20
21
22 char *
23 setview(v) /* set hvec and vvec, return message on error */
24 register VIEW *v;
25 {
26 static char ill_horiz[] = "illegal horizontal view size";
27 static char ill_vert[] = "illegal vertical view size";
28
29 if (normalize(v->vdir) == 0.0) /* normalize direction */
30 return("zero view direction");
31
32 if (normalize(v->vup) == 0.0) /* normalize view up */
33 return("zero view up vector");
34
35 fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
36
37 if (normalize(v->hvec) == 0.0)
38 return("view up parallel to view direction");
39
40 fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
41
42 if (v->horiz <= FTINY)
43 return(ill_horiz);
44 if (v->vert <= FTINY)
45 return(ill_vert);
46
47 switch (v->type) {
48 case VT_PAR: /* parallel view */
49 v->hn2 = v->horiz;
50 v->vn2 = v->vert;
51 break;
52 case VT_PER: /* perspective view */
53 if (v->horiz >= 180.0-FTINY)
54 return(ill_horiz);
55 if (v->vert >= 180.0-FTINY)
56 return(ill_vert);
57 v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
58 v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
59 break;
60 case VT_ANG: /* angular fisheye */
61 if (v->horiz > 360.0+FTINY)
62 return(ill_horiz);
63 if (v->vert > 360.0+FTINY)
64 return(ill_vert);
65 v->hn2 = v->horiz / 90.0;
66 v->vn2 = v->vert / 90.0;
67 break;
68 case VT_HEM: /* hemispherical fisheye */
69 if (v->horiz > 180.0+FTINY)
70 return(ill_horiz);
71 if (v->vert > 180.0+FTINY)
72 return(ill_vert);
73 v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
74 v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
75 break;
76 default:
77 return("unknown view type");
78 }
79 if (v->type != VT_ANG) {
80 v->hvec[0] *= v->hn2;
81 v->hvec[1] *= v->hn2;
82 v->hvec[2] *= v->hn2;
83 v->vvec[0] *= v->vn2;
84 v->vvec[1] *= v->vn2;
85 v->vvec[2] *= v->vn2;
86 }
87 v->hn2 *= v->hn2;
88 v->vn2 *= v->vn2;
89
90 return(NULL);
91 }
92
93
94 normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
95 double va; /* view aspect ratio */
96 double *ap; /* pixel aspect in (or out if 0) */
97 int *xp, *yp; /* x and y resolution in (or out if *ap!=0) */
98 {
99 if (*ap <= FTINY)
100 *ap = va * *xp / *yp; /* compute pixel aspect */
101 else if (va * *xp > *ap * *yp)
102 *xp = *yp / va * *ap + .5; /* reduce x resolution */
103 else
104 *yp = *xp * va / *ap + .5; /* reduce y resolution */
105 }
106
107
108 viewray(orig, direc, v, x, y) /* compute ray origin and direction */
109 FVECT orig, direc;
110 register VIEW *v;
111 double x, y;
112 {
113 double d, z;
114
115 x += v->hoff - 0.5;
116 y += v->voff - 0.5;
117
118 switch(v->type) {
119 case VT_PAR: /* parallel view */
120 orig[0] = v->vp[0] + x*v->hvec[0] + y*v->vvec[0];
121 orig[1] = v->vp[1] + x*v->hvec[1] + y*v->vvec[1];
122 orig[2] = v->vp[2] + x*v->hvec[2] + y*v->vvec[2];
123 VCOPY(direc, v->vdir);
124 return(0);
125 case VT_PER: /* perspective view */
126 VCOPY(orig, v->vp);
127 direc[0] = v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
128 direc[1] = v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
129 direc[2] = v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
130 normalize(direc);
131 return(0);
132 case VT_HEM: /* hemispherical fisheye */
133 z = 1.0 - x*x*v->hn2 - y*y*v->vn2;
134 if (z < 0.0)
135 return(-1);
136 z = sqrt(z);
137 VCOPY(orig, v->vp);
138 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
139 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
140 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
141 return(0);
142 case VT_ANG: /* angular fisheye */
143 x *= v->horiz/180.0;
144 y *= v->vert/180.0;
145 d = x*x + y*y;
146 if (d > 1.0)
147 return(-1);
148 VCOPY(orig, v->vp);
149 if (d <= FTINY) {
150 VCOPY(direc, v->vdir);
151 return(0);
152 }
153 d = sqrt(d);
154 z = cos(PI*d);
155 d = sqrt(1 - z*z)/d;
156 x *= d;
157 y *= d;
158 direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
159 direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
160 direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
161 return(0);
162 }
163 return(-1);
164 }
165
166
167 viewloc(ip, v, p) /* find image location for point */
168 FVECT ip;
169 register VIEW *v;
170 FVECT p;
171 {
172 double d;
173 FVECT disp;
174
175 disp[0] = p[0] - v->vp[0];
176 disp[1] = p[1] - v->vp[1];
177 disp[2] = p[2] - v->vp[2];
178
179 switch (v->type) {
180 case VT_PAR: /* parallel view */
181 ip[2] = DOT(disp,v->vdir);
182 break;
183 case VT_PER: /* perspective view */
184 d = DOT(disp,v->vdir);
185 ip[2] = sqrt(DOT(disp,disp));
186 if (d < 0.0) { /* fold pyramid */
187 ip[2] = -ip[2];
188 d = -d;
189 } else if (d > FTINY) {
190 d = 1.0/d;
191 disp[0] *= d;
192 disp[1] *= d;
193 disp[2] *= d;
194 }
195 break;
196 case VT_HEM: /* hemispherical fisheye */
197 d = normalize(disp);
198 if (DOT(disp,v->vdir) < 0.0)
199 ip[2] = -d;
200 else
201 ip[2] = d;
202 break;
203 case VT_ANG: /* angular fisheye */
204 ip[0] = 0.5 - v->hoff;
205 ip[1] = 0.5 - v->voff;
206 ip[2] = normalize(disp);
207 d = DOT(disp,v->vdir);
208 if (d >= 1.0-FTINY)
209 return;
210 if (d <= -(1.0-FTINY)) {
211 ip[1] += 180.0/v->horiz;
212 ip[2] += 180.0/v->vert;
213 return;
214 }
215 d = acos(d)/PI / sqrt(1.0 - d*d);
216 ip[0] += DOT(disp,v->hvec)*d*180.0/v->horiz;
217 ip[1] += DOT(disp,v->vvec)*d*180.0/v->vert;
218 return;
219 }
220 ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
221 ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
222 }
223
224
225 pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
226 FLOAT loc[2];
227 register RESOLU *rp;
228 int px, py;
229 {
230 register int x, y;
231
232 if (rp->or & YMAJOR) {
233 x = px;
234 y = py;
235 } else {
236 x = py;
237 y = px;
238 }
239 if (rp->or & XDECR)
240 x = rp->xr-1 - x;
241 if (rp->or & YDECR)
242 y = rp->yr-1 - y;
243 loc[0] = (x+.5)/rp->xr;
244 loc[1] = (y+.5)/rp->yr;
245 }
246
247
248 loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
249 int pp[2];
250 register RESOLU *rp;
251 double lx, ly;
252 {
253 register int x, y;
254
255 x = lx * rp->xr;
256 y = ly * rp->yr;
257 if (rp->or & XDECR)
258 x = rp->xr-1 - x;
259 if (rp->or & YDECR)
260 y = rp->yr-1 - y;
261 if (rp->or & YMAJOR) {
262 pp[0] = x;
263 pp[1] = y;
264 } else {
265 pp[0] = y;
266 pp[1] = x;
267 }
268 }
269
270
271 int
272 getviewopt(v, ac, av) /* process view argument */
273 register VIEW *v;
274 int ac;
275 register char *av[];
276 {
277 #define check(c,l) if ((av[0][c]&&av[0][c]!=' ') || \
278 badarg(ac-1,av+1,l)) return(-1)
279
280 if (ac <= 0 || av[0][0] != '-' || av[0][1] != 'v')
281 return(-1);
282 switch (av[0][2]) {
283 case 't': /* type */
284 if (!av[0][3] || av[0][3]==' ')
285 return(-1);
286 check(4,"");
287 v->type = av[0][3];
288 return(0);
289 case 'p': /* point */
290 check(3,"fff");
291 v->vp[0] = atof(av[1]);
292 v->vp[1] = atof(av[2]);
293 v->vp[2] = atof(av[3]);
294 return(3);
295 case 'd': /* direction */
296 check(3,"fff");
297 v->vdir[0] = atof(av[1]);
298 v->vdir[1] = atof(av[2]);
299 v->vdir[2] = atof(av[3]);
300 return(3);
301 case 'u': /* up */
302 check(3,"fff");
303 v->vup[0] = atof(av[1]);
304 v->vup[1] = atof(av[2]);
305 v->vup[2] = atof(av[3]);
306 return(3);
307 case 'h': /* horizontal size */
308 check(3,"f");
309 v->horiz = atof(av[1]);
310 return(1);
311 case 'v': /* vertical size */
312 check(3,"f");
313 v->vert = atof(av[1]);
314 return(1);
315 case 's': /* shift */
316 check(3,"f");
317 v->hoff = atof(av[1]);
318 return(1);
319 case 'l': /* lift */
320 check(3,"f");
321 v->voff = atof(av[1]);
322 return(1);
323 default:
324 return(-1);
325 }
326 #undef check
327 }
328
329
330 int
331 sscanview(vp, s) /* get view parameters from string */
332 VIEW *vp;
333 register char *s;
334 {
335 int ac;
336 char *av[4];
337 int na;
338 int nvopts = 0;
339
340 if (*s != '-')
341 s = sskip(s);
342 while (*s) {
343 ac = 0;
344 do {
345 av[ac++] = s;
346 while (*s && *s != ' ')
347 s++;
348 while (*s == ' ')
349 s++;
350 } while (*s && ac < 4);
351 if ((na = getviewopt(vp, ac, av)) >= 0) {
352 if (na+1 < ac)
353 s = av[na+1];
354 nvopts++;
355 } else if (ac > 1)
356 s = av[1];
357 }
358 return(nvopts);
359 }
360
361
362 fprintview(vp, fp) /* write out view parameters */
363 register VIEW *vp;
364 FILE *fp;
365 {
366 fprintf(fp, " -vt%c", vp->type);
367 fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
368 fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
369 fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
370 fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
371 fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
372 }
373
374
375 int
376 isview(s) /* is this a view string? */
377 char *s;
378 {
379 static char *altname[]={NULL,"rpict","rview","pinterp",VIEWSTR,NULL};
380 extern char *progname, *rindex();
381 register char *cp;
382 register char **an;
383 /* add program name to list */
384 if (altname[0] == NULL)
385 if ((cp = rindex(progname, '/')) != NULL)
386 altname[0] = cp+1;
387 else
388 altname[0] = progname;
389 /* skip leading path */
390 cp = s;
391 while (*cp && *cp != ' ')
392 cp++;
393 while (cp > s && cp[-1] != '/')
394 cp--;
395 for (an = altname; *an != NULL; an++)
396 if (!strncmp(*an, cp, strlen(*an)))
397 return(1);
398 return(0);
399 }
400
401
402 struct myview {
403 VIEW *hv;
404 int ok;
405 };
406
407
408 static
409 gethview(s, v) /* get view from header */
410 char *s;
411 register struct myview *v;
412 {
413 if (isview(s) && sscanview(v->hv, s) > 0)
414 v->ok++;
415 }
416
417
418 int
419 viewfile(fname, vp, rp) /* get view from file */
420 char *fname;
421 VIEW *vp;
422 RESOLU *rp;
423 {
424 struct myview mvs;
425 FILE *fp;
426
427 if ((fp = fopen(fname, "r")) == NULL)
428 return(-1);
429
430 mvs.hv = vp;
431 mvs.ok = 0;
432
433 getheader(fp, gethview, &mvs);
434
435 if (rp != NULL && !fgetsresolu(rp, fp))
436 mvs.ok = 0;
437
438 fclose(fp);
439
440 return(mvs.ok);
441 }