1 |
< |
/* Copyright (c) 1991 Regents of the University of California */ |
1 |
> |
/* Copyright (c) 1992 Regents of the University of California */ |
2 |
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3 |
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#ifndef lint |
4 |
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static char SCCSid[] = "$SunId$ LBL"; |
15 |
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#ifdef BSD |
16 |
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#include <sys/time.h> |
17 |
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#include <sys/resource.h> |
18 |
– |
#else |
19 |
– |
#include <signal.h> |
18 |
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#endif |
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+ |
|
20 |
+ |
#include <signal.h> |
21 |
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#include <fcntl.h> |
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|
23 |
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#include "view.h" |
24 |
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|
25 |
+ |
#include "resolu.h" |
26 |
+ |
|
27 |
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#include "random.h" |
28 |
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|
29 |
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int dimlist[MAXDIM]; /* sampling dimensions */ |
42 |
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double dstrsrc = 0.0; /* square source distribution */ |
43 |
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double shadthresh = .05; /* shadow threshold */ |
44 |
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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 |
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|
50 |
+ |
double specthresh = .15; /* specular sampling threshold */ |
51 |
+ |
double specjitter = 1.; /* specular sampling jitter */ |
52 |
+ |
|
53 |
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int maxdepth = 6; /* maximum recursion depth */ |
54 |
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double minweight = 5e-3; /* minimum ray weight */ |
55 |
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|
73 |
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|
74 |
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extern long nrays; /* number of rays traced */ |
75 |
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|
76 |
< |
#define MAXDIV 15 /* maximum sample size */ |
76 |
> |
#define MAXDIV 16 /* maximum sample size */ |
77 |
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|
78 |
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#define pixjitter() (.5+dstrpix*(.5-frandom())) |
79 |
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|
80 |
+ |
#define RFTEMPLATE "rfXXXXXX" |
81 |
+ |
#define HFTEMPLATE "/tmp/hfXXXXXX" |
82 |
+ |
|
83 |
+ |
static char *hfname = NULL; /* header file name */ |
84 |
+ |
static FILE *hfp = NULL; /* header file pointer */ |
85 |
+ |
|
86 |
+ |
static int hres, vres; /* resolution for this frame */ |
87 |
+ |
|
88 |
+ |
extern char *mktemp(); |
89 |
+ |
|
90 |
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double pixvalue(); |
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|
92 |
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|
93 |
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quit(code) /* quit program */ |
94 |
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int code; |
95 |
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{ |
96 |
< |
if (code || ralrm > 0) /* report status */ |
96 |
> |
if (code) /* report status */ |
97 |
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report(); |
98 |
< |
|
98 |
> |
if (hfname != NULL) { /* delete header file */ |
99 |
> |
if (hfp != NULL) |
100 |
> |
fclose(hfp); |
101 |
> |
unlink(hfname); |
102 |
> |
} |
103 |
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exit(code); |
104 |
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} |
105 |
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|
125 |
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#else |
126 |
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report() /* report progress */ |
127 |
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{ |
105 |
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signal(SIGALRM, report); |
128 |
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tlastrept = time((long *)0); |
129 |
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sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f hours\n", |
130 |
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nrays, pctdone, (tlastrept-tstart)/3600.0); |
131 |
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eputs(errmsg); |
132 |
+ |
signal(SIGALRM, report); |
133 |
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} |
134 |
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#endif |
135 |
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|
136 |
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|
137 |
+ |
openheader() /* save standard output to header file */ |
138 |
+ |
{ |
139 |
+ |
hfname = mktemp(HFTEMPLATE); |
140 |
+ |
if (freopen(hfname, "w", stdout) == NULL) { |
141 |
+ |
sprintf(errmsg, "cannot open header file \"%s\"", hfname); |
142 |
+ |
error(SYSTEM, errmsg); |
143 |
+ |
} |
144 |
+ |
} |
145 |
+ |
|
146 |
+ |
|
147 |
+ |
closeheader() /* done with header output */ |
148 |
+ |
{ |
149 |
+ |
if (hfname == NULL) |
150 |
+ |
return; |
151 |
+ |
if (fflush(stdout) == EOF || (hfp = fopen(hfname, "r")) == NULL) |
152 |
+ |
error(SYSTEM, "error reopening header file"); |
153 |
+ |
} |
154 |
+ |
|
155 |
+ |
|
156 |
+ |
dupheader() /* repeat header on standard output */ |
157 |
+ |
{ |
158 |
+ |
register int c; |
159 |
+ |
|
160 |
+ |
if (fseek(hfp, 0L, 0) < 0) |
161 |
+ |
error(SYSTEM, "seek error on header file"); |
162 |
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while ((c = getc(hfp)) != EOF) |
163 |
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putchar(c); |
164 |
+ |
} |
165 |
+ |
|
166 |
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|
167 |
+ |
rpict(seq, pout, zout, prvr) /* generate image(s) */ |
168 |
+ |
int seq; |
169 |
+ |
char *pout, *zout, *prvr; |
170 |
+ |
/* |
171 |
+ |
* If seq is greater than zero, then we will render a sequence of |
172 |
+ |
* images based on view parameter strings read from the standard input. |
173 |
+ |
* If pout is NULL, then all images will be sent to the standard ouput. |
174 |
+ |
* If seq is greater than zero and prvr is an integer, then it is the |
175 |
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* frame number at which rendering should begin. Preceeding view parameter |
176 |
+ |
* strings will be skipped in the input. |
177 |
+ |
* If pout and prvr are the same, prvr is renamed to avoid overwriting. |
178 |
+ |
* Note that pout and zout should contain %d format specifications for |
179 |
+ |
* sequenced file naming. |
180 |
+ |
*/ |
181 |
+ |
{ |
182 |
+ |
extern char *rindex(), *strncpy(), *strcat(); |
183 |
+ |
char fbuf[128], fbuf2[128]; |
184 |
+ |
register char *cp; |
185 |
+ |
RESOLU rs; |
186 |
+ |
double pa; |
187 |
+ |
/* finished writing header */ |
188 |
+ |
closeheader(); |
189 |
+ |
/* check sampling */ |
190 |
+ |
if (psample < 1) |
191 |
+ |
psample = 1; |
192 |
+ |
else if (psample > MAXDIV) { |
193 |
+ |
sprintf(errmsg, "pixel sampling reduced from %d to %d", |
194 |
+ |
psample, MAXDIV); |
195 |
+ |
error(WARNING, errmsg); |
196 |
+ |
psample = MAXDIV; |
197 |
+ |
} |
198 |
+ |
/* get starting frame */ |
199 |
+ |
if (seq <= 0) |
200 |
+ |
seq = 0; |
201 |
+ |
else if (prvr != NULL && isint(prvr)) { |
202 |
+ |
register int rn; /* skip to specified view */ |
203 |
+ |
if ((rn = atoi(prvr)) < seq) |
204 |
+ |
error(USER, "recover frame less than start frame"); |
205 |
+ |
if (pout == NULL) |
206 |
+ |
error(USER, "missing output file specification"); |
207 |
+ |
for ( ; seq < rn; seq++) |
208 |
+ |
if (nextview(stdin) == EOF) |
209 |
+ |
error(USER, "unexpected EOF on view input"); |
210 |
+ |
prvr = fbuf; /* mark for renaming */ |
211 |
+ |
} |
212 |
+ |
if (pout != NULL) { |
213 |
+ |
sprintf(fbuf, pout, seq); |
214 |
+ |
if (prvr != NULL && !strcmp(prvr, fbuf)) { /* rename */ |
215 |
+ |
fbuf2[0] = '\0'; |
216 |
+ |
if ((cp = rindex(fbuf, '/')) != NULL) |
217 |
+ |
strncpy(fbuf2, fbuf, cp-fbuf+1); |
218 |
+ |
strcat(fbuf2, RFTEMPLATE); |
219 |
+ |
prvr = mktemp(fbuf2); |
220 |
+ |
if (rename(fbuf, prvr) < 0 && errno != ENOENT) { |
221 |
+ |
sprintf(errmsg, |
222 |
+ |
"cannot rename \"%s\" to \"%s\"", |
223 |
+ |
fbuf, prvr); |
224 |
+ |
error(SYSTEM, errmsg); |
225 |
+ |
} |
226 |
+ |
} |
227 |
+ |
} |
228 |
+ |
/* render sequence */ |
229 |
+ |
do { |
230 |
+ |
if (seq && nextview(stdin) == EOF) |
231 |
+ |
break; |
232 |
+ |
if (pout != NULL) { |
233 |
+ |
sprintf(fbuf, pout, seq); |
234 |
+ |
if (freopen(fbuf, "w", stdout) == NULL) { |
235 |
+ |
sprintf(errmsg, |
236 |
+ |
"cannot open output file \"%s\"", fbuf); |
237 |
+ |
error(SYSTEM, errmsg); |
238 |
+ |
} |
239 |
+ |
dupheader(); |
240 |
+ |
} |
241 |
+ |
hres = hresolu; vres = vresolu; pa = pixaspect; |
242 |
+ |
if (prvr != NULL) |
243 |
+ |
if (viewfile(prvr, &ourview, &rs) <= 0 |
244 |
+ |
|| rs.or != PIXSTANDARD) { |
245 |
+ |
sprintf(errmsg, |
246 |
+ |
"cannot recover view parameters from \"%s\"", prvr); |
247 |
+ |
error(WARNING, errmsg); |
248 |
+ |
} else { |
249 |
+ |
pa = 0.0; |
250 |
+ |
hres = scanlen(&rs); |
251 |
+ |
vres = numscans(&rs); |
252 |
+ |
} |
253 |
+ |
if ((cp = setview(&ourview)) != NULL) |
254 |
+ |
error(USER, cp); |
255 |
+ |
normaspect(viewaspect(&ourview), &pa, &hres, &vres); |
256 |
+ |
if (seq) { |
257 |
+ |
if (ralrm > 0) { |
258 |
+ |
fprintf(stderr, "FRAME %d:", seq); |
259 |
+ |
fprintview(&ourview, stderr); |
260 |
+ |
putc('\n', stderr); |
261 |
+ |
fflush(stderr); |
262 |
+ |
} |
263 |
+ |
printf("FRAME=%d\n", seq); |
264 |
+ |
} |
265 |
+ |
fputs(VIEWSTR, stdout); |
266 |
+ |
fprintview(&ourview, stdout); |
267 |
+ |
putchar('\n'); |
268 |
+ |
if (pa < .99 || pa > 1.01) |
269 |
+ |
fputaspect(pa, stdout); |
270 |
+ |
fputformat(COLRFMT, stdout); |
271 |
+ |
putchar('\n'); |
272 |
+ |
if (zout != NULL) |
273 |
+ |
sprintf(cp=fbuf, zout, seq); |
274 |
+ |
else |
275 |
+ |
cp = NULL; |
276 |
+ |
render(cp, prvr); |
277 |
+ |
prvr = NULL; |
278 |
+ |
} while (seq++); |
279 |
+ |
} |
280 |
+ |
|
281 |
+ |
|
282 |
+ |
nextview(fp) /* get next view from fp */ |
283 |
+ |
FILE *fp; |
284 |
+ |
{ |
285 |
+ |
char linebuf[256]; |
286 |
+ |
|
287 |
+ |
while (fgets(linebuf, sizeof(linebuf), fp) != NULL) |
288 |
+ |
if (isview(linebuf) && sscanview(&ourview, linebuf) > 0) |
289 |
+ |
return(0); |
290 |
+ |
return(EOF); |
291 |
+ |
} |
292 |
+ |
|
293 |
+ |
|
294 |
|
render(zfile, oldfile) /* render the scene */ |
295 |
|
char *zfile, *oldfile; |
296 |
|
{ |
297 |
|
extern long lseek(); |
298 |
|
COLOR *scanbar[MAXDIV+1]; /* scanline arrays of pixel values */ |
299 |
|
float *zbar[MAXDIV+1]; /* z values */ |
300 |
+ |
char *sampdens; /* previous sample density */ |
301 |
|
int ypos; /* current scanline */ |
302 |
|
int ystep; /* current y step size */ |
303 |
+ |
int hstep; /* h step size */ |
304 |
|
int zfd; |
305 |
|
COLOR *colptr; |
306 |
|
float *zptr; |
307 |
|
register int i; |
126 |
– |
/* check sampling */ |
127 |
– |
if (psample < 1) |
128 |
– |
psample = 1; |
129 |
– |
else if (psample > MAXDIV) { |
130 |
– |
sprintf(errmsg, "pixel sampling reduced from %d to %d", |
131 |
– |
psample, MAXDIV); |
132 |
– |
error(WARNING, errmsg); |
133 |
– |
psample = MAXDIV; |
134 |
– |
} |
308 |
|
/* allocate scanlines */ |
309 |
|
for (i = 0; i <= psample; i++) { |
310 |
< |
scanbar[i] = (COLOR *)malloc(hresolu*sizeof(COLOR)); |
310 |
> |
scanbar[i] = (COLOR *)malloc(hres*sizeof(COLOR)); |
311 |
|
if (scanbar[i] == NULL) |
312 |
|
goto memerr; |
313 |
|
} |
314 |
+ |
hstep = (psample*140+49)/99; /* quincunx sampling */ |
315 |
+ |
ystep = (psample*99+70)/140; |
316 |
+ |
if (hstep > 2) { |
317 |
+ |
i = hres/hstep + 2; |
318 |
+ |
if ((sampdens = malloc(i)) == NULL) |
319 |
+ |
goto memerr; |
320 |
+ |
while (i--) |
321 |
+ |
sampdens[i] = hstep; |
322 |
+ |
} else |
323 |
+ |
sampdens = NULL; |
324 |
|
/* open z file */ |
325 |
|
if (zfile != NULL) { |
326 |
|
if ((zfd = open(zfile, O_WRONLY|O_CREAT, 0666)) == -1) { |
328 |
|
error(SYSTEM, errmsg); |
329 |
|
} |
330 |
|
for (i = 0; i <= psample; i++) { |
331 |
< |
zbar[i] = (float *)malloc(hresolu*sizeof(float)); |
331 |
> |
zbar[i] = (float *)malloc(hres*sizeof(float)); |
332 |
|
if (zbar[i] == NULL) |
333 |
|
goto memerr; |
334 |
|
} |
338 |
|
zbar[i] = NULL; |
339 |
|
} |
340 |
|
/* write out boundaries */ |
341 |
< |
fputresolu(YMAJOR|YDECR, hresolu, vresolu, stdout); |
341 |
> |
fprtresolu(hres, vres, stdout); |
342 |
|
/* recover file and compute first */ |
343 |
|
i = salvage(oldfile); |
344 |
|
if (zfd != -1 && i > 0 && |
345 |
< |
lseek(zfd, (long)i*hresolu*sizeof(float), 0) == -1) |
345 |
> |
lseek(zfd, (long)i*hres*sizeof(float), 0) == -1) |
346 |
|
error(SYSTEM, "z file seek error in render"); |
347 |
< |
pctdone = 100.0*i/vresolu; |
347 |
> |
pctdone = 100.0*i/vres; |
348 |
|
if (ralrm > 0) /* report init stats */ |
349 |
|
report(); |
350 |
< |
ypos = vresolu-1 - i; |
351 |
< |
fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample); |
352 |
< |
ystep = psample; |
350 |
> |
#ifndef BSD |
351 |
> |
else |
352 |
> |
#endif |
353 |
> |
signal(SIGALRM, report); |
354 |
> |
ypos = vres-1 - i; |
355 |
> |
fillscanline(scanbar[0], zbar[0], sampdens, hres, ypos, hstep); |
356 |
|
/* compute scanlines */ |
357 |
|
for (ypos -= ystep; ypos > -ystep; ypos -= ystep) { |
358 |
|
/* bottom adjust? */ |
367 |
|
zbar[ystep] = zbar[0]; |
368 |
|
zbar[0] = zptr; |
369 |
|
/* fill base line */ |
370 |
< |
fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample); |
370 |
> |
fillscanline(scanbar[0], zbar[0], sampdens, |
371 |
> |
hres, ypos, hstep); |
372 |
|
/* fill bar */ |
373 |
< |
fillscanbar(scanbar, zbar, hresolu, ypos, ystep); |
373 |
> |
fillscanbar(scanbar, zbar, hres, ypos, ystep); |
374 |
|
/* write it out */ |
375 |
+ |
#ifndef BSD |
376 |
+ |
signal(SIGALRM, SIG_IGN); /* don't interrupt writes */ |
377 |
+ |
#endif |
378 |
|
for (i = ystep; i > 0; i--) { |
379 |
|
if (zfd != -1 && write(zfd, (char *)zbar[i], |
380 |
< |
hresolu*sizeof(float)) |
381 |
< |
< hresolu*sizeof(float)) |
380 |
> |
hres*sizeof(float)) |
381 |
> |
< hres*sizeof(float)) |
382 |
|
goto writerr; |
383 |
< |
if (fwritescan(scanbar[i], hresolu, stdout) < 0) |
383 |
> |
if (fwritescan(scanbar[i], hres, stdout) < 0) |
384 |
|
goto writerr; |
385 |
|
} |
386 |
|
if (fflush(stdout) == EOF) |
387 |
|
goto writerr; |
388 |
|
/* record progress */ |
389 |
< |
pctdone = 100.0*(vresolu-1-ypos)/vresolu; |
389 |
> |
pctdone = 100.0*(vres-1-ypos)/vres; |
390 |
|
if (ralrm > 0 && time((long *)0) >= tlastrept+ralrm) |
391 |
|
report(); |
392 |
+ |
#ifndef BSD |
393 |
+ |
else |
394 |
+ |
signal(SIGALRM, report); |
395 |
+ |
#endif |
396 |
|
} |
397 |
|
/* clean up */ |
398 |
+ |
signal(SIGALRM, SIG_IGN); |
399 |
|
if (zfd != -1) { |
400 |
< |
if (write(zfd, (char *)zbar[0], hresolu*sizeof(float)) |
401 |
< |
< hresolu*sizeof(float)) |
400 |
> |
if (write(zfd, (char *)zbar[0], hres*sizeof(float)) |
401 |
> |
< hres*sizeof(float)) |
402 |
|
goto writerr; |
403 |
|
if (close(zfd) == -1) |
404 |
|
goto writerr; |
405 |
|
for (i = 0; i <= psample; i++) |
406 |
|
free((char *)zbar[i]); |
407 |
|
} |
408 |
< |
fwritescan(scanbar[0], hresolu, stdout); |
408 |
> |
fwritescan(scanbar[0], hres, stdout); |
409 |
|
if (fflush(stdout) == EOF) |
410 |
|
goto writerr; |
411 |
|
for (i = 0; i <= psample; i++) |
412 |
|
free((char *)scanbar[i]); |
413 |
+ |
if (sampdens != NULL) |
414 |
+ |
free(sampdens); |
415 |
|
pctdone = 100.0; |
416 |
|
return; |
417 |
|
writerr: |
421 |
|
} |
422 |
|
|
423 |
|
|
424 |
< |
fillscanline(scanline, zline, xres, y, xstep) /* fill scan line at y */ |
424 |
> |
fillscanline(scanline, zline, sd, xres, y, xstep) /* fill scan at y */ |
425 |
|
register COLOR *scanline; |
426 |
|
register float *zline; |
427 |
+ |
register char *sd; |
428 |
|
int xres, y, xstep; |
429 |
|
{ |
430 |
< |
int b = xstep; |
430 |
> |
static int nc = 0; /* number of calls */ |
431 |
> |
int bl = xstep, b = xstep; |
432 |
|
double z; |
433 |
|
register int i; |
434 |
|
|
435 |
|
z = pixvalue(scanline[0], 0, y); |
436 |
|
if (zline) zline[0] = z; |
437 |
< |
|
438 |
< |
for (i = xstep; i < xres-1+xstep; i += xstep) { |
437 |
> |
/* zig-zag start for quincunx pattern */ |
438 |
> |
for (i = ++nc & 1 ? xstep : xstep/2; i < xres-1+xstep; i += xstep) { |
439 |
|
if (i >= xres) { |
440 |
|
xstep += xres-1-i; |
441 |
|
i = xres-1; |
442 |
|
} |
443 |
|
z = pixvalue(scanline[i], i, y); |
444 |
|
if (zline) zline[i] = z; |
445 |
< |
|
446 |
< |
b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL, |
447 |
< |
i-xstep, y, xstep, 0, b/2); |
445 |
> |
if (sd) b = sd[0] > sd[1] ? sd[0] : sd[1]; |
446 |
> |
if (i <= xstep) |
447 |
> |
b = fillsample(scanline, zline, 0, y, i, 0, b/2); |
448 |
> |
else |
449 |
> |
b = fillsample(scanline+i-xstep, |
450 |
> |
zline ? zline+i-xstep : NULL, |
451 |
> |
i-xstep, y, xstep, 0, b/2); |
452 |
> |
if (sd) *sd++ = nc & 1 ? bl : b; |
453 |
> |
bl = b; |
454 |
|
} |
455 |
+ |
if (sd && nc & 1) *sd = bl; |
456 |
|
} |
457 |
|
|
458 |
|
|
550 |
|
static RAY thisray; |
551 |
|
|
552 |
|
if (viewray(thisray.rorg, thisray.rdir, &ourview, |
553 |
< |
(x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) { |
553 |
> |
(x+pixjitter())/hres, (y+pixjitter())/vres) < 0) { |
554 |
|
setcolor(col, 0.0, 0.0, 0.0); |
555 |
|
return(0.0); |
556 |
|
} |
557 |
|
|
558 |
|
rayorigin(&thisray, NULL, PRIMARY, 1.0); |
559 |
|
|
560 |
< |
samplendx = 3*y + x; /* set pixel index */ |
560 |
> |
samplendx = pixnumber(x,y,hres,vres); /* set pixel index */ |
561 |
|
|
562 |
|
rayvalue(&thisray); /* trace ray */ |
563 |
|
|
586 |
|
/* discard header */ |
587 |
|
getheader(fp, NULL); |
588 |
|
/* get picture size */ |
589 |
< |
if (fgetresolu(&x, &y, fp) != (YMAJOR|YDECR)) { |
589 |
> |
if (!fscnresolu(&x, &y, fp)) { |
590 |
|
sprintf(errmsg, "bad recover file \"%s\"", oldfile); |
591 |
|
error(WARNING, errmsg); |
592 |
|
fclose(fp); |
593 |
|
return(0); |
594 |
|
} |
595 |
|
|
596 |
< |
if (x != hresolu || y != vresolu) { |
596 |
> |
if (x != hres || y != vres) { |
597 |
|
sprintf(errmsg, "resolution mismatch in recover file \"%s\"", |
598 |
|
oldfile); |
599 |
|
error(USER, errmsg); |
600 |
|
} |
601 |
|
|
602 |
< |
scanline = (COLR *)malloc(hresolu*sizeof(COLR)); |
602 |
> |
scanline = (COLR *)malloc(hres*sizeof(COLR)); |
603 |
|
if (scanline == NULL) |
604 |
|
error(SYSTEM, "out of memory in salvage"); |
605 |
< |
for (y = 0; y < vresolu; y++) { |
606 |
< |
if (freadcolrs(scanline, hresolu, fp) < 0) |
605 |
> |
for (y = 0; y < vres; y++) { |
606 |
> |
if (freadcolrs(scanline, hres, fp) < 0) |
607 |
|
break; |
608 |
< |
if (fwritecolrs(scanline, hresolu, stdout) < 0) |
608 |
> |
if (fwritecolrs(scanline, hres, stdout) < 0) |
609 |
|
goto writerr; |
610 |
|
} |
611 |
|
if (fflush(stdout) == EOF) |
615 |
|
unlink(oldfile); |
616 |
|
return(y); |
617 |
|
writerr: |
618 |
< |
error(SYSTEM, "write error in salvage"); |
618 |
> |
sprintf(errmsg, "write error during recovery of \"%s\"", oldfile); |
619 |
> |
error(SYSTEM, errmsg); |
620 |
> |
} |
621 |
> |
|
622 |
> |
|
623 |
> |
int |
624 |
> |
pixnumber(x, y, xres, yres) /* compute pixel index (brushed) */ |
625 |
> |
register int x, y; |
626 |
> |
int xres, yres; |
627 |
> |
{ |
628 |
> |
x -= y; |
629 |
> |
while (x < 0) |
630 |
> |
x += xres; |
631 |
> |
return((((x>>2)*yres + y) << 2) + (x & 3)); |
632 |
|
} |