src/rt/rpict.c

/* Copyright (c) 1991 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  rpict.c - routines and variables for picture generation.
 *
 *     8/14/85
 */

#include  "ray.h"

#ifdef BSD
#include  <sys/time.h>
#include  <sys/resource.h>
#else
#include  <signal.h>
#endif
#include  <fcntl.h>

#include  "view.h"

#include  "random.h"

int  dimlist[MAXDIM];                   /* sampling dimensions */
int  ndims = 0;                         /* number of sampling dimensions */
int  samplendx;                         /* sample index number */

VIEW  ourview = STDVIEW;                /* view parameters */
int  hresolu = 512;                     /* horizontal resolution */
int  vresolu = 512;                     /* vertical resolution */
double  pixaspect = 1.0;                /* pixel aspect ratio */

int  psample = 4;                       /* pixel sample size */
double  maxdiff = .05;                  /* max. difference for interpolation */
double  dstrpix = 0.67;                 /* square pixel distribution */
int  psuper = 2;                        /* pixel super-sampling rate */

double  dstrsrc = 0.0;                  /* square source distribution */
double  shadthresh = .05;               /* shadow threshold */
double  shadcert = .5;                  /* shadow certainty */

int  maxdepth = 6;                      /* maximum recursion depth */
double  minweight = 5e-3;               /* minimum ray weight */

COLOR  ambval = BLKCOLOR;               /* ambient value */
double  ambacc = 0.2;                   /* ambient accuracy */
int  ambres = 32;                       /* ambient resolution */
int  ambdiv = 128;                      /* ambient divisions */
int  ambssamp = 0;                      /* ambient super-samples */
int  ambounce = 0;                      /* ambient bounces */
char  *amblist[128];                    /* ambient include/exclude list */
int  ambincl = -1;                      /* include == 1, exclude == 0 */

int  ralrm = 0;                         /* seconds between reports */

double  pctdone = 0.0;                  /* percentage done */

long  tlastrept = 0L;                   /* time at last report */

extern long  time();
extern long  tstart;                    /* starting time */

extern long  nrays;                     /* number of rays traced */

#define  MAXDIV         32              /* maximum sample size */

#define  pixjitter()    (.5+dstrpix*(.5-frandom()))

double  pixvalue();


quit(code)                      /* quit program */
int  code;
{
        if (code || ralrm > 0)          /* report status */
                report();

        exit(code);
}


#ifdef BSD
report()                /* report progress */
{
        struct rusage  rubuf;
        double  t;

        getrusage(RUSAGE_SELF, &rubuf);
        t = (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
        t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
        getrusage(RUSAGE_CHILDREN, &rubuf);
        t += (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
        t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;

        sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f CPU hours\n",
                        nrays, pctdone, t/3600.0);
        eputs(errmsg);
        tlastrept = time((long *)0);
}
#else
report()                /* report progress */
{
        signal(SIGALRM, report);
        tlastrept = time((long *)0);
        sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f hours\n",
                        nrays, pctdone, (tlastrept-tstart)/3600.0);
        eputs(errmsg);
}
#endif


render(zfile, oldfile)                          /* render the scene */
char  *zfile, *oldfile;
{
        extern long  lseek();
        COLOR  *scanbar[MAXDIV+1];      /* scanline arrays of pixel values */
        float  *zbar[MAXDIV+1];         /* z values */
        int  ypos;                      /* current scanline */
        int  ystep;                     /* current y step size */
        int  zfd;
        COLOR  *colptr;
        float  *zptr;
        register int  i;
                                        /* check sampling */
        if (psample < 1)
                psample = 1;
        else if (psample > MAXDIV)
                psample = MAXDIV;
                                        /* allocate scanlines */
        for (i = 0; i <= psample; i++) {
                scanbar[i] = (COLOR *)malloc(hresolu*sizeof(COLOR));
                if (scanbar[i] == NULL)
                        goto memerr;
        }
                                        /* open z file */
        if (zfile != NULL) {
                if ((zfd = open(zfile, O_WRONLY|O_CREAT, 0666)) == -1) {
                        sprintf(errmsg, "cannot open z file \"%s\"", zfile);
                        error(SYSTEM, errmsg);
                }
                for (i = 0; i <= psample; i++) {
                        zbar[i] = (float *)malloc(hresolu*sizeof(float));
                        if (zbar[i] == NULL)
                                goto memerr;
                }
        } else {
                zfd = -1;
                for (i = 0; i <= psample; i++)
                        zbar[i] = NULL;
        }
                                        /* write out boundaries */
        fputresolu(YMAJOR|YDECR, hresolu, vresolu, stdout);
                                        /* recover file and compute first */
        i = salvage(oldfile);
        if (zfd != -1 && i > 0 &&
                        lseek(zfd, (long)i*hresolu*sizeof(float), 0) == -1)
                error(SYSTEM, "z file seek error in render");
        pctdone = 100.0*i/vresolu;
        if (ralrm > 0)                  /* report init stats */
                report();
        ypos = vresolu-1 - i;
        fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
        ystep = psample;
                                                /* compute scanlines */
        for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
                                                        /* bottom adjust? */
                if (ypos < 0) {
                        ystep += ypos;
                        ypos = 0;
                }
                colptr = scanbar[ystep];                /* move base to top */
                scanbar[ystep] = scanbar[0];
                scanbar[0] = colptr;
                zptr = zbar[ystep];
                zbar[ystep] = zbar[0];
                zbar[0] = zptr;
                                                        /* fill base line */
                fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
                                                        /* fill bar */
                fillscanbar(scanbar, zbar, hresolu, ypos, ystep);
                                                        /* write it out */
                for (i = ystep; i > 0; i--) {
                        if (zfd != -1 && write(zfd, (char *)zbar[i],
                                        hresolu*sizeof(float))
                                        < hresolu*sizeof(float))
                                goto writerr;
                        if (fwritescan(scanbar[i], hresolu, stdout) < 0)
                                goto writerr;
                }
                if (fflush(stdout) == EOF)
                        goto writerr;
                                                        /* record progress */
                pctdone = 100.0*(vresolu-1-ypos)/vresolu;
                if (ralrm > 0 && time((long *)0) >= tlastrept+ralrm)
                        report();
        }
                                                /* clean up */
        if (zfd != -1) {
                if (write(zfd, (char *)zbar[0], hresolu*sizeof(float))
                                < hresolu*sizeof(float))
                        goto writerr;
                if (close(zfd) == -1)
                        goto writerr;
                for (i = 0; i <= psample; i++)
                        free((char *)zbar[i]);
        }
        fwritescan(scanbar[0], hresolu, stdout);
        if (fflush(stdout) == EOF)
                goto writerr;
        for (i = 0; i <= psample; i++)
                free((char *)scanbar[i]);
        pctdone = 100.0;
        return;
writerr:
        error(SYSTEM, "write error in render");
memerr:
        error(SYSTEM, "out of memory in render");
}


fillscanline(scanline, zline, xres, y, xstep)   /* fill scan line at y */
register COLOR  *scanline;
register float  *zline;
int  xres, y, xstep;
{
        int  b = xstep;
        double  z;
        register int  i;
        
        z = pixvalue(scanline[0], 0, y);
        if (zline) zline[0] = z;

        for (i = xstep; i < xres-1+xstep; i += xstep) {
                if (i >= xres) {
                        xstep += xres-1-i;
                        i = xres-1;
                }
                z = pixvalue(scanline[i], i, y);
                if (zline) zline[i] = z;
                
                b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
                                i-xstep, y, xstep, 0, b/2);
        }
}


fillscanbar(scanbar, zbar, xres, y, ysize)      /* fill interior */
register COLOR  *scanbar[];
register float  *zbar[];
int  xres, y, ysize;
{
        COLOR  vline[MAXDIV+1];
        float  zline[MAXDIV+1];
        int  b = ysize;
        register int  i, j;
        
        for (i = 0; i < xres; i++) {
                
                copycolor(vline[0], scanbar[0][i]);
                copycolor(vline[ysize], scanbar[ysize][i]);
                if (zbar[0]) {
                        zline[0] = zbar[0][i];
                        zline[ysize] = zbar[ysize][i];
                }
                
                b = fillsample(vline, zbar[0] ? zline : NULL,
                                i, y, 0, ysize, b/2);
                
                for (j = 1; j < ysize; j++)
                        copycolor(scanbar[j][i], vline[j]);
                if (zbar[0])
                        for (j = 1; j < ysize; j++)
                                zbar[j][i] = zline[j];
        }
}


int
fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
register COLOR  *colline;
register float  *zline;
int  x, y;
int  xlen, ylen;
int  b;
{
        extern double  fabs();
        double  ratio;
        double  z;
        COLOR  ctmp;
        int  ncut;
        register int  len;
        
        if (xlen > 0)                   /* x or y length is zero */
                len = xlen;
        else
                len = ylen;
                
        if (len <= 1)                   /* limit recursion */
                return(0);
        
        if (b > 0
        || (zline && 2.*fabs(zline[0]-zline[len]) > maxdiff*(zline[0]+zline[len]))
                        || bigdiff(colline[0], colline[len], maxdiff)) {
        
                z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
                if (zline) zline[len>>1] = z;
                ncut = 1;
                
        } else {                                        /* interpolate */
        
                copycolor(colline[len>>1], colline[len]);
                ratio = (double)(len>>1) / len;
                scalecolor(colline[len>>1], ratio);
                if (zline) zline[len>>1] = zline[len] * ratio;
                ratio = 1.0 - ratio;
                copycolor(ctmp, colline[0]);
                scalecolor(ctmp, ratio);
                addcolor(colline[len>>1], ctmp);
                if (zline) zline[len>>1] += zline[0] * ratio;
                ncut = 0;
        }
                                                        /* recurse */
        ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
        
        ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
                        x+(xlen>>1), y+(ylen>>1),
                        xlen-(xlen>>1), ylen-(ylen>>1), b/2);

        return(ncut);
}


double
pixvalue(col, x, y)             /* compute pixel value */
COLOR  col;                     /* returned color */
int  x, y;                      /* pixel position */
{
        static RAY  thisray;

        if (viewray(thisray.rorg, thisray.rdir, &ourview,
                        (x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) {
                setcolor(col, 0.0, 0.0, 0.0);
                return(0.0);
        }

        rayorigin(&thisray, NULL, PRIMARY, 1.0);

        samplendx = 3*y + x;                    /* set pixel index */

        rayvalue(&thisray);                     /* trace ray */

        copycolor(col, thisray.rcol);           /* return color */
        
        return(thisray.rt);                     /* return distance */
}


int
salvage(oldfile)                /* salvage scanlines from killed program */
char  *oldfile;
{
        COLR  *scanline;
        FILE  *fp;
        int  x, y;

        if (oldfile == NULL)
                return(0);
        
        if ((fp = fopen(oldfile, "r")) == NULL) {
                sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
                error(WARNING, errmsg);
                return(0);
        }
                                /* discard header */
        getheader(fp, NULL);
                                /* get picture size */
        if (fgetresolu(&x, &y, fp) != (YMAJOR|YDECR)) {
                sprintf(errmsg, "bad recover file \"%s\"", oldfile);
                error(WARNING, errmsg);
                fclose(fp);
                return(0);
        }

        if (x != hresolu || y != vresolu) {
                sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
                                oldfile);
                error(USER, errmsg);
        }

        scanline = (COLR *)malloc(hresolu*sizeof(COLR));
        if (scanline == NULL)
                error(SYSTEM, "out of memory in salvage");
        for (y = 0; y < vresolu; y++) {
                if (freadcolrs(scanline, hresolu, fp) < 0)
                        break;
                if (fwritecolrs(scanline, hresolu, stdout) < 0)
                        goto writerr;
        }
        if (fflush(stdout) == EOF)
                goto writerr;
        free((char *)scanline);
        fclose(fp);
        unlink(oldfile);
        return(y);
writerr:
        error(SYSTEM, "write error in salvage");
}
Revision:	1.25
Committed:	Tue May 21 17:41:35 1991 UTC (32 years, 11 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.24:	+9 -2 lines
Log Message:	added stratified random sampling with urand
#	User	Rev	Content
1	greg	1.24	/* Copyright (c) 1991 Regents of the University of California */
2	greg	1.1
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	greg	1.14	#else
19			#include <signal.h>
20	greg	1.1	#endif
21	greg	1.18	#include <fcntl.h>
22	greg	1.1
23			#include "view.h"
24
25			#include "random.h"
26
27	greg	1.25	int dimlist[MAXDIM]; /* sampling dimensions */
28			int ndims = 0; /* number of sampling dimensions */
29			int samplendx; /* sample index number */
30
31	greg	1.12	VIEW ourview = STDVIEW; /* view parameters */
32			int hresolu = 512; /* horizontal resolution */
33			int vresolu = 512; /* vertical resolution */
34	greg	1.13	double pixaspect = 1.0; /* pixel aspect ratio */
35	greg	1.1
36			int psample = 4; /* pixel sample size */
37			double maxdiff = .05; /* max. difference for interpolation */
38	greg	1.3	double dstrpix = 0.67; /* square pixel distribution */
39	greg	1.25	int psuper = 2; /* pixel super-sampling rate */
40	greg	1.1
41			double dstrsrc = 0.0; /* square source distribution */
42	greg	1.4	double shadthresh = .05; /* shadow threshold */
43	greg	1.5	double shadcert = .5; /* shadow certainty */
44	greg	1.1
45			int maxdepth = 6; /* maximum recursion depth */
46			double minweight = 5e-3; /* minimum ray weight */
47
48			COLOR ambval = BLKCOLOR; /* ambient value */
49			double ambacc = 0.2; /* ambient accuracy */
50	greg	1.6	int ambres = 32; /* ambient resolution */
51	greg	1.1	int ambdiv = 128; /* ambient divisions */
52			int ambssamp = 0; /* ambient super-samples */
53			int ambounce = 0; /* ambient bounces */
54			char amblist[128]; / ambient include/exclude list */
55			int ambincl = -1; /* include == 1, exclude == 0 */
56
57			int ralrm = 0; /* seconds between reports */
58
59			double pctdone = 0.0; /* percentage done */
60
61	greg	1.24	long tlastrept = 0L; /* time at last report */
62
63			extern long time();
64			extern long tstart; /* starting time */
65
66	greg	1.1	extern long nrays; /* number of rays traced */
67
68			#define MAXDIV 32 /* maximum sample size */
69
70			#define pixjitter() (.5+dstrpix*(.5-frandom()))
71
72	greg	1.11	double pixvalue();
73	greg	1.1
74	greg	1.11
75	greg	1.1	quit(code) /* quit program */
76			int code;
77			{
78			if (code \|\| ralrm > 0) /* report status */
79			report();
80
81			exit(code);
82			}
83
84
85	greg	1.24	#ifdef BSD
86	greg	1.1	report() /* report progress */
87			{
88			struct rusage rubuf;
89			double t;
90
91			getrusage(RUSAGE_SELF, &rubuf);
92			t = (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
93			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
94			getrusage(RUSAGE_CHILDREN, &rubuf);
95			t += (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
96			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
97
98			sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f CPU hours\n",
99			nrays, pctdone, t/3600.0);
100	greg	1.24	eputs(errmsg);
101			tlastrept = time((long *)0);
102			}
103	greg	1.1	#else
104	greg	1.24	report() /* report progress */
105			{
106	greg	1.14	signal(SIGALRM, report);
107	greg	1.24	tlastrept = time((long *)0);
108			sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f hours\n",
109			nrays, pctdone, (tlastrept-tstart)/3600.0);
110	greg	1.1	eputs(errmsg);
111			}
112	greg	1.24	#endif
113	greg	1.1
114
115	greg	1.11	render(zfile, oldfile) /* render the scene */
116			char zfile, oldfile;
117	greg	1.1	{
118	greg	1.16	extern long lseek();
119	greg	1.1	COLOR scanbar[MAXDIV+1]; / scanline arrays of pixel values */
120	greg	1.11	float zbar[MAXDIV+1]; / z values */
121	greg	1.1	int ypos; /* current scanline */
122	greg	1.15	int ystep; /* current y step size */
123	greg	1.16	int zfd;
124	greg	1.1	COLOR *colptr;
125	greg	1.11	float *zptr;
126	greg	1.1	register int i;
127	greg	1.10	/* check sampling */
128			if (psample < 1)
129	greg	1.1	psample = 1;
130	greg	1.10	else if (psample > MAXDIV)
131			psample = MAXDIV;
132	greg	1.9	/* allocate scanlines */
133	greg	1.1	for (i = 0; i <= psample; i++) {
134	greg	1.12	scanbar[i] = (COLOR )malloc(hresolusizeof(COLOR));
135	greg	1.1	if (scanbar[i] == NULL)
136	greg	1.11	goto memerr;
137	greg	1.1	}
138	greg	1.11	/* open z file */
139			if (zfile != NULL) {
140	greg	1.16	if ((zfd = open(zfile, O_WRONLY\|O_CREAT, 0666)) == -1) {
141	greg	1.11	sprintf(errmsg, "cannot open z file \"%s\"", zfile);
142			error(SYSTEM, errmsg);
143			}
144			for (i = 0; i <= psample; i++) {
145	greg	1.12	zbar[i] = (float )malloc(hresolusizeof(float));
146	greg	1.11	if (zbar[i] == NULL)
147			goto memerr;
148			}
149			} else {
150	greg	1.16	zfd = -1;
151	greg	1.11	for (i = 0; i <= psample; i++)
152			zbar[i] = NULL;
153			}
154	greg	1.1	/* write out boundaries */
155	greg	1.12	fputresolu(YMAJOR\|YDECR, hresolu, vresolu, stdout);
156	greg	1.10	/* recover file and compute first */
157	greg	1.11	i = salvage(oldfile);
158	greg	1.23	if (zfd != -1 && i > 0 &&
159			lseek(zfd, (long)ihresolusizeof(float), 0) == -1)
160	greg	1.11	error(SYSTEM, "z file seek error in render");
161	greg	1.24	pctdone = 100.0*i/vresolu;
162			if (ralrm > 0) /* report init stats */
163			report();
164	greg	1.12	ypos = vresolu-1 - i;
165			fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
166	greg	1.15	ystep = psample;
167	greg	1.10	/* compute scanlines */
168	greg	1.15	for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
169			/* bottom adjust? */
170			if (ypos < 0) {
171			ystep += ypos;
172			ypos = 0;
173			}
174			colptr = scanbar[ystep]; /* move base to top */
175			scanbar[ystep] = scanbar[0];
176	greg	1.1	scanbar[0] = colptr;
177	greg	1.15	zptr = zbar[ystep];
178			zbar[ystep] = zbar[0];
179	greg	1.11	zbar[0] = zptr;
180	greg	1.10	/* fill base line */
181	greg	1.12	fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
182	greg	1.10	/* fill bar */
183	greg	1.15	fillscanbar(scanbar, zbar, hresolu, ypos, ystep);
184	greg	1.10	/* write it out */
185	greg	1.15	for (i = ystep; i > 0; i--) {
186	greg	1.17	if (zfd != -1 && write(zfd, (char *)zbar[i],
187			hresolu*sizeof(float))
188	greg	1.16	< hresolu*sizeof(float))
189	greg	1.1	goto writerr;
190	greg	1.17	if (fwritescan(scanbar[i], hresolu, stdout) < 0)
191	greg	1.11	goto writerr;
192			}
193	greg	1.1	if (fflush(stdout) == EOF)
194			goto writerr;
195	greg	1.24	/* record progress */
196			pctdone = 100.0*(vresolu-1-ypos)/vresolu;
197			if (ralrm > 0 && time((long *)0) >= tlastrept+ralrm)
198			report();
199	greg	1.1	}
200	greg	1.11	/* clean up */
201	greg	1.16	if (zfd != -1) {
202	greg	1.17	if (write(zfd, (char )zbar[0], hresolusizeof(float))
203	greg	1.16	< hresolu*sizeof(float))
204	greg	1.11	goto writerr;
205	greg	1.20	if (close(zfd) == -1)
206			goto writerr;
207	greg	1.11	for (i = 0; i <= psample; i++)
208			free((char *)zbar[i]);
209			}
210	greg	1.15	fwritescan(scanbar[0], hresolu, stdout);
211	greg	1.10	if (fflush(stdout) == EOF)
212			goto writerr;
213	greg	1.1	for (i = 0; i <= psample; i++)
214			free((char *)scanbar[i]);
215	greg	1.11	pctdone = 100.0;
216	greg	1.1	return;
217			writerr:
218			error(SYSTEM, "write error in render");
219	greg	1.11	memerr:
220			error(SYSTEM, "out of memory in render");
221	greg	1.1	}
222
223
224	greg	1.11	fillscanline(scanline, zline, xres, y, xstep) /* fill scan line at y */
225	greg	1.1	register COLOR *scanline;
226	greg	1.11	register float *zline;
227	greg	1.9	int xres, y, xstep;
228	greg	1.1	{
229			int b = xstep;
230	greg	1.11	double z;
231	greg	1.1	register int i;
232
233	greg	1.11	z = pixvalue(scanline[0], 0, y);
234			if (zline) zline[0] = z;
235	greg	1.1
236	greg	1.15	for (i = xstep; i < xres-1+xstep; i += xstep) {
237			if (i >= xres) {
238			xstep += xres-1-i;
239			i = xres-1;
240			}
241	greg	1.11	z = pixvalue(scanline[i], i, y);
242			if (zline) zline[i] = z;
243	greg	1.1
244	greg	1.11	b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
245			i-xstep, y, xstep, 0, b/2);
246	greg	1.1	}
247			}
248
249
250	greg	1.11	fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
251	greg	1.1	register COLOR *scanbar[];
252	greg	1.11	register float *zbar[];
253	greg	1.9	int xres, y, ysize;
254	greg	1.1	{
255			COLOR vline[MAXDIV+1];
256	greg	1.11	float zline[MAXDIV+1];
257	greg	1.1	int b = ysize;
258			register int i, j;
259
260	greg	1.8	for (i = 0; i < xres; i++) {
261	greg	1.1
262			copycolor(vline[0], scanbar[0][i]);
263			copycolor(vline[ysize], scanbar[ysize][i]);
264	greg	1.11	if (zbar[0]) {
265			zline[0] = zbar[0][i];
266			zline[ysize] = zbar[ysize][i];
267			}
268	greg	1.1
269	greg	1.11	b = fillsample(vline, zbar[0] ? zline : NULL,
270			i, y, 0, ysize, b/2);
271	greg	1.1
272			for (j = 1; j < ysize; j++)
273			copycolor(scanbar[j][i], vline[j]);
274	greg	1.11	if (zbar[0])
275			for (j = 1; j < ysize; j++)
276			zbar[j][i] = zline[j];
277	greg	1.1	}
278			}
279
280
281			int
282	greg	1.11	fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
283	greg	1.1	register COLOR *colline;
284	greg	1.11	register float *zline;
285	greg	1.1	int x, y;
286			int xlen, ylen;
287			int b;
288			{
289	greg	1.11	extern double fabs();
290	greg	1.1	double ratio;
291	greg	1.11	double z;
292	greg	1.1	COLOR ctmp;
293			int ncut;
294			register int len;
295
296			if (xlen > 0) /* x or y length is zero */
297			len = xlen;
298			else
299			len = ylen;
300
301			if (len <= 1) /* limit recursion */
302			return(0);
303
304	greg	1.11	if (b > 0
305			\|\| (zline && 2.fabs(zline[0]-zline[len]) > maxdiff(zline[0]+zline[len]))
306			\|\| bigdiff(colline[0], colline[len], maxdiff)) {
307	greg	1.1
308	greg	1.11	z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
309			if (zline) zline[len>>1] = z;
310	greg	1.1	ncut = 1;
311
312			} else { /* interpolate */
313
314			copycolor(colline[len>>1], colline[len]);
315			ratio = (double)(len>>1) / len;
316			scalecolor(colline[len>>1], ratio);
317	greg	1.11	if (zline) zline[len>>1] = zline[len] * ratio;
318			ratio = 1.0 - ratio;
319	greg	1.1	copycolor(ctmp, colline[0]);
320			scalecolor(ctmp, ratio);
321			addcolor(colline[len>>1], ctmp);
322	greg	1.11	if (zline) zline[len>>1] += zline[0] * ratio;
323	greg	1.1	ncut = 0;
324			}
325			/* recurse */
326	greg	1.11	ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
327	greg	1.1
328	greg	1.11	ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
329			x+(xlen>>1), y+(ylen>>1),
330			xlen-(xlen>>1), ylen-(ylen>>1), b/2);
331	greg	1.1
332			return(ncut);
333			}
334
335
336	greg	1.11	double
337	greg	1.1	pixvalue(col, x, y) /* compute pixel value */
338			COLOR col; /* returned color */
339			int x, y; /* pixel position */
340			{
341	greg	1.25	static RAY thisray;
342	greg	1.1
343	greg	1.22	if (viewray(thisray.rorg, thisray.rdir, &ourview,
344			(x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) {
345			setcolor(col, 0.0, 0.0, 0.0);
346			return(0.0);
347			}
348	greg	1.1
349			rayorigin(&thisray, NULL, PRIMARY, 1.0);
350	greg	1.25
351			samplendx = 3y + x; / set pixel index */
352
353	greg	1.1	rayvalue(&thisray); /* trace ray */
354
355			copycolor(col, thisray.rcol); /* return color */
356	greg	1.11
357	greg	1.20	return(thisray.rt); /* return distance */
358	greg	1.1	}
359
360
361			int
362			salvage(oldfile) /* salvage scanlines from killed program */
363			char *oldfile;
364			{
365			COLR *scanline;
366			FILE *fp;
367			int x, y;
368
369			if (oldfile == NULL)
370			return(0);
371	greg	1.9
372			if ((fp = fopen(oldfile, "r")) == NULL) {
373	greg	1.1	sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
374			error(WARNING, errmsg);
375			return(0);
376			}
377			/* discard header */
378			getheader(fp, NULL);
379			/* get picture size */
380	greg	1.7	if (fgetresolu(&x, &y, fp) != (YMAJOR\|YDECR)) {
381	greg	1.2	sprintf(errmsg, "bad recover file \"%s\"", oldfile);
382			error(WARNING, errmsg);
383	greg	1.1	fclose(fp);
384			return(0);
385			}
386
387	greg	1.12	if (x != hresolu \|\| y != vresolu) {
388	greg	1.1	sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
389			oldfile);
390			error(USER, errmsg);
391			}
392
393	greg	1.12	scanline = (COLR )malloc(hresolusizeof(COLR));
394	greg	1.1	if (scanline == NULL)
395			error(SYSTEM, "out of memory in salvage");
396	greg	1.12	for (y = 0; y < vresolu; y++) {
397			if (freadcolrs(scanline, hresolu, fp) < 0)
398	greg	1.1	break;
399	greg	1.12	if (fwritecolrs(scanline, hresolu, stdout) < 0)
400	greg	1.1	goto writerr;
401			}
402			if (fflush(stdout) == EOF)
403			goto writerr;
404			free((char *)scanline);
405			fclose(fp);
406			unlink(oldfile);
407			return(y);
408			writerr:
409			error(SYSTEM, "write error in salvage");
410			}