ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/ray/src/rt/rpict.c
Revision: 2.2
Committed: Thu Nov 21 10:10:46 1991 UTC (32 years, 5 months ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.1: +25 -9 lines
Log Message:
improved sampling

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 * rpict.c - routines and variables for picture generation.
9 *
10 * 8/14/85
11 */
12
13 #include "ray.h"
14
15 #ifdef BSD
16 #include <sys/time.h>
17 #include <sys/resource.h>
18 #endif
19
20 #include <signal.h>
21 #include <fcntl.h>
22
23 #include "view.h"
24
25 #include "resolu.h"
26
27 #include "random.h"
28
29 int dimlist[MAXDIM]; /* sampling dimensions */
30 int ndims = 0; /* number of sampling dimensions */
31 int samplendx; /* sample index number */
32
33 VIEW ourview = STDVIEW; /* view parameters */
34 int hresolu = 512; /* horizontal resolution */
35 int vresolu = 512; /* vertical resolution */
36 double pixaspect = 1.0; /* pixel aspect ratio */
37
38 int psample = 4; /* pixel sample size */
39 double maxdiff = .05; /* max. difference for interpolation */
40 double dstrpix = 0.67; /* square pixel distribution */
41
42 double dstrsrc = 0.0; /* square source distribution */
43 double shadthresh = .05; /* shadow threshold */
44 double shadcert = .5; /* shadow certainty */
45 int directrelay = 1; /* number of source relays */
46 int vspretest = 512; /* virtual source pretest density */
47 int directinvis = 0; /* sources invisible? */
48 double srcsizerat = .25; /* maximum ratio source size/dist. */
49
50 int maxdepth = 6; /* maximum recursion depth */
51 double minweight = 5e-3; /* minimum ray weight */
52
53 COLOR ambval = BLKCOLOR; /* ambient value */
54 double ambacc = 0.2; /* ambient accuracy */
55 int ambres = 32; /* ambient resolution */
56 int ambdiv = 128; /* ambient divisions */
57 int ambssamp = 0; /* ambient super-samples */
58 int ambounce = 0; /* ambient bounces */
59 char *amblist[128]; /* ambient include/exclude list */
60 int ambincl = -1; /* include == 1, exclude == 0 */
61
62 int ralrm = 0; /* seconds between reports */
63
64 double pctdone = 0.0; /* percentage done */
65
66 long tlastrept = 0L; /* time at last report */
67
68 extern long time();
69 extern long tstart; /* starting time */
70
71 extern long nrays; /* number of rays traced */
72
73 #define MAXDIV 16 /* maximum sample size */
74
75 #define pixjitter() (.5+dstrpix*(.5-frandom()))
76
77 double pixvalue();
78
79
80 quit(code) /* quit program */
81 int code;
82 {
83 if (code || ralrm > 0) /* report status */
84 report();
85
86 exit(code);
87 }
88
89
90 #ifdef BSD
91 report() /* report progress */
92 {
93 struct rusage rubuf;
94 double t;
95
96 getrusage(RUSAGE_SELF, &rubuf);
97 t = (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
98 t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
99 getrusage(RUSAGE_CHILDREN, &rubuf);
100 t += (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
101 t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
102
103 sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f CPU hours\n",
104 nrays, pctdone, t/3600.0);
105 eputs(errmsg);
106 tlastrept = time((long *)0);
107 }
108 #else
109 report() /* report progress */
110 {
111 signal(SIGALRM, report);
112 tlastrept = time((long *)0);
113 sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f hours\n",
114 nrays, pctdone, (tlastrept-tstart)/3600.0);
115 eputs(errmsg);
116 }
117 #endif
118
119
120 render(zfile, oldfile) /* render the scene */
121 char *zfile, *oldfile;
122 {
123 extern long lseek();
124 COLOR *scanbar[MAXDIV+1]; /* scanline arrays of pixel values */
125 float *zbar[MAXDIV+1]; /* z values */
126 char *sampdens; /* previous sample density */
127 int ypos; /* current scanline */
128 int ystep; /* current y step size */
129 int hstep; /* h step size */
130 int zfd;
131 COLOR *colptr;
132 float *zptr;
133 register int i;
134 /* check sampling */
135 if (psample < 1)
136 psample = 1;
137 else if (psample > MAXDIV) {
138 sprintf(errmsg, "pixel sampling reduced from %d to %d",
139 psample, MAXDIV);
140 error(WARNING, errmsg);
141 psample = MAXDIV;
142 }
143 /* allocate scanlines */
144 for (i = 0; i <= psample; i++) {
145 scanbar[i] = (COLOR *)malloc(hresolu*sizeof(COLOR));
146 if (scanbar[i] == NULL)
147 goto memerr;
148 }
149 hstep = (psample*140+49)/99; /* quincunx sampling */
150 ystep = (psample*99+70)/140;
151 if (hstep > 2) {
152 i = hresolu/hstep + 2;
153 if ((sampdens = malloc(i)) == NULL)
154 goto memerr;
155 while (i--)
156 sampdens[i] = hstep;
157 } else
158 sampdens = NULL;
159 /* open z file */
160 if (zfile != NULL) {
161 if ((zfd = open(zfile, O_WRONLY|O_CREAT, 0666)) == -1) {
162 sprintf(errmsg, "cannot open z file \"%s\"", zfile);
163 error(SYSTEM, errmsg);
164 }
165 for (i = 0; i <= psample; i++) {
166 zbar[i] = (float *)malloc(hresolu*sizeof(float));
167 if (zbar[i] == NULL)
168 goto memerr;
169 }
170 } else {
171 zfd = -1;
172 for (i = 0; i <= psample; i++)
173 zbar[i] = NULL;
174 }
175 /* write out boundaries */
176 fprtresolu(hresolu, vresolu, stdout);
177 /* recover file and compute first */
178 i = salvage(oldfile);
179 if (zfd != -1 && i > 0 &&
180 lseek(zfd, (long)i*hresolu*sizeof(float), 0) == -1)
181 error(SYSTEM, "z file seek error in render");
182 pctdone = 100.0*i/vresolu;
183 if (ralrm > 0) /* report init stats */
184 report();
185 #ifndef BSD
186 else
187 #endif
188 signal(SIGALRM, report);
189 ypos = vresolu-1 - i;
190 fillscanline(scanbar[0], zbar[0], sampdens, hresolu, ypos, hstep);
191 /* compute scanlines */
192 for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
193 /* bottom adjust? */
194 if (ypos < 0) {
195 ystep += ypos;
196 ypos = 0;
197 }
198 colptr = scanbar[ystep]; /* move base to top */
199 scanbar[ystep] = scanbar[0];
200 scanbar[0] = colptr;
201 zptr = zbar[ystep];
202 zbar[ystep] = zbar[0];
203 zbar[0] = zptr;
204 /* fill base line */
205 fillscanline(scanbar[0], zbar[0], sampdens,
206 hresolu, ypos, hstep);
207 /* fill bar */
208 fillscanbar(scanbar, zbar, hresolu, ypos, ystep);
209 /* write it out */
210 #ifndef BSD
211 signal(SIGALRM, SIG_IGN); /* don't interrupt writes */
212 #endif
213 for (i = ystep; i > 0; i--) {
214 if (zfd != -1 && write(zfd, (char *)zbar[i],
215 hresolu*sizeof(float))
216 < hresolu*sizeof(float))
217 goto writerr;
218 if (fwritescan(scanbar[i], hresolu, stdout) < 0)
219 goto writerr;
220 }
221 if (fflush(stdout) == EOF)
222 goto writerr;
223 /* record progress */
224 pctdone = 100.0*(vresolu-1-ypos)/vresolu;
225 if (ralrm > 0 && time((long *)0) >= tlastrept+ralrm)
226 report();
227 #ifndef BSD
228 else
229 signal(SIGALRM, report);
230 #endif
231 }
232 /* clean up */
233 if (zfd != -1) {
234 if (write(zfd, (char *)zbar[0], hresolu*sizeof(float))
235 < hresolu*sizeof(float))
236 goto writerr;
237 if (close(zfd) == -1)
238 goto writerr;
239 for (i = 0; i <= psample; i++)
240 free((char *)zbar[i]);
241 }
242 fwritescan(scanbar[0], hresolu, stdout);
243 if (fflush(stdout) == EOF)
244 goto writerr;
245 for (i = 0; i <= psample; i++)
246 free((char *)scanbar[i]);
247 if (sampdens != NULL)
248 free(sampdens);
249 pctdone = 100.0;
250 return;
251 writerr:
252 error(SYSTEM, "write error in render");
253 memerr:
254 error(SYSTEM, "out of memory in render");
255 }
256
257
258 fillscanline(scanline, zline, sd, xres, y, xstep) /* fill scan at y */
259 register COLOR *scanline;
260 register float *zline;
261 register char *sd;
262 int xres, y, xstep;
263 {
264 static int nc = 0; /* number of calls */
265 int bl = xstep, b = xstep;
266 double z;
267 register int i;
268
269 z = pixvalue(scanline[0], 0, y);
270 if (zline) zline[0] = z;
271 /* zig-zag start for quincunx pattern */
272 for (i = ++nc & 1 ? xstep : xstep/2; i < xres-1+xstep; i += xstep) {
273 if (i >= xres) {
274 xstep += xres-1-i;
275 i = xres-1;
276 }
277 z = pixvalue(scanline[i], i, y);
278 if (zline) zline[i] = z;
279 if (sd) b = sd[0] > sd[1] ? sd[0] : sd[1];
280 b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
281 i-xstep, y, xstep, 0, b/2);
282 if (sd) *sd++ = nc & 1 ? bl : b;
283 bl = b;
284 }
285 if (sd && nc & 1) *sd = bl;
286 }
287
288
289 fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
290 register COLOR *scanbar[];
291 register float *zbar[];
292 int xres, y, ysize;
293 {
294 COLOR vline[MAXDIV+1];
295 float zline[MAXDIV+1];
296 int b = ysize;
297 register int i, j;
298
299 for (i = 0; i < xres; i++) {
300
301 copycolor(vline[0], scanbar[0][i]);
302 copycolor(vline[ysize], scanbar[ysize][i]);
303 if (zbar[0]) {
304 zline[0] = zbar[0][i];
305 zline[ysize] = zbar[ysize][i];
306 }
307
308 b = fillsample(vline, zbar[0] ? zline : NULL,
309 i, y, 0, ysize, b/2);
310
311 for (j = 1; j < ysize; j++)
312 copycolor(scanbar[j][i], vline[j]);
313 if (zbar[0])
314 for (j = 1; j < ysize; j++)
315 zbar[j][i] = zline[j];
316 }
317 }
318
319
320 int
321 fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
322 register COLOR *colline;
323 register float *zline;
324 int x, y;
325 int xlen, ylen;
326 int b;
327 {
328 extern double fabs();
329 double ratio;
330 double z;
331 COLOR ctmp;
332 int ncut;
333 register int len;
334
335 if (xlen > 0) /* x or y length is zero */
336 len = xlen;
337 else
338 len = ylen;
339
340 if (len <= 1) /* limit recursion */
341 return(0);
342
343 if (b > 0
344 || (zline && 2.*fabs(zline[0]-zline[len]) > maxdiff*(zline[0]+zline[len]))
345 || bigdiff(colline[0], colline[len], maxdiff)) {
346
347 z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
348 if (zline) zline[len>>1] = z;
349 ncut = 1;
350
351 } else { /* interpolate */
352
353 copycolor(colline[len>>1], colline[len]);
354 ratio = (double)(len>>1) / len;
355 scalecolor(colline[len>>1], ratio);
356 if (zline) zline[len>>1] = zline[len] * ratio;
357 ratio = 1.0 - ratio;
358 copycolor(ctmp, colline[0]);
359 scalecolor(ctmp, ratio);
360 addcolor(colline[len>>1], ctmp);
361 if (zline) zline[len>>1] += zline[0] * ratio;
362 ncut = 0;
363 }
364 /* recurse */
365 ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
366
367 ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
368 x+(xlen>>1), y+(ylen>>1),
369 xlen-(xlen>>1), ylen-(ylen>>1), b/2);
370
371 return(ncut);
372 }
373
374
375 double
376 pixvalue(col, x, y) /* compute pixel value */
377 COLOR col; /* returned color */
378 int x, y; /* pixel position */
379 {
380 static RAY thisray;
381
382 if (viewray(thisray.rorg, thisray.rdir, &ourview,
383 (x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) {
384 setcolor(col, 0.0, 0.0, 0.0);
385 return(0.0);
386 }
387
388 rayorigin(&thisray, NULL, PRIMARY, 1.0);
389
390 samplendx = pixnumber(x,y,hresolu,vresolu); /* set pixel index */
391
392 rayvalue(&thisray); /* trace ray */
393
394 copycolor(col, thisray.rcol); /* return color */
395
396 return(thisray.rt); /* return distance */
397 }
398
399
400 int
401 salvage(oldfile) /* salvage scanlines from killed program */
402 char *oldfile;
403 {
404 COLR *scanline;
405 FILE *fp;
406 int x, y;
407
408 if (oldfile == NULL)
409 return(0);
410
411 if ((fp = fopen(oldfile, "r")) == NULL) {
412 sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
413 error(WARNING, errmsg);
414 return(0);
415 }
416 /* discard header */
417 getheader(fp, NULL);
418 /* get picture size */
419 if (!fscnresolu(&x, &y, fp)) {
420 sprintf(errmsg, "bad recover file \"%s\"", oldfile);
421 error(WARNING, errmsg);
422 fclose(fp);
423 return(0);
424 }
425
426 if (x != hresolu || y != vresolu) {
427 sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
428 oldfile);
429 error(USER, errmsg);
430 }
431
432 scanline = (COLR *)malloc(hresolu*sizeof(COLR));
433 if (scanline == NULL)
434 error(SYSTEM, "out of memory in salvage");
435 for (y = 0; y < vresolu; y++) {
436 if (freadcolrs(scanline, hresolu, fp) < 0)
437 break;
438 if (fwritecolrs(scanline, hresolu, stdout) < 0)
439 goto writerr;
440 }
441 if (fflush(stdout) == EOF)
442 goto writerr;
443 free((char *)scanline);
444 fclose(fp);
445 unlink(oldfile);
446 return(y);
447 writerr:
448 error(SYSTEM, "write error in salvage");
449 }
450
451
452 int
453 pixnumber(x, y, xres, yres) /* compute pixel index (brushed) */
454 register int x, y;
455 int xres, yres;
456 {
457 x -= y;
458 while (x < 0)
459 x += xres;
460 return((((x>>2)*yres + y) << 2) + (x & 3));
461 }