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"

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 */

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;    /* our ray for this pixel */

        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);
        
        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:	1.24
Committed:	Tue Apr 9 09:31:01 1991 UTC (33 years ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.23:	+23 -9 lines
Log Message:	changed reporting so that alarm() is not used.
#	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	1.12	VIEW ourview = STDVIEW; /* view parameters */
28			int hresolu = 512; /* horizontal resolution */
29			int vresolu = 512; /* vertical resolution */
30	greg	1.13	double pixaspect = 1.0; /* pixel aspect ratio */
31	greg	1.1
32			int psample = 4; /* pixel sample size */
33			double maxdiff = .05; /* max. difference for interpolation */
34	greg	1.3	double dstrpix = 0.67; /* square pixel distribution */
35	greg	1.1
36			double dstrsrc = 0.0; /* square source distribution */
37	greg	1.4	double shadthresh = .05; /* shadow threshold */
38	greg	1.5	double shadcert = .5; /* shadow certainty */
39	greg	1.1
40			int maxdepth = 6; /* maximum recursion depth */
41			double minweight = 5e-3; /* minimum ray weight */
42
43			COLOR ambval = BLKCOLOR; /* ambient value */
44			double ambacc = 0.2; /* ambient accuracy */
45	greg	1.6	int ambres = 32; /* ambient resolution */
46	greg	1.1	int ambdiv = 128; /* ambient divisions */
47			int ambssamp = 0; /* ambient super-samples */
48			int ambounce = 0; /* ambient bounces */
49			char amblist[128]; / ambient include/exclude list */
50			int ambincl = -1; /* include == 1, exclude == 0 */
51
52			int ralrm = 0; /* seconds between reports */
53
54			double pctdone = 0.0; /* percentage done */
55
56	greg	1.24	long tlastrept = 0L; /* time at last report */
57
58			extern long time();
59			extern long tstart; /* starting time */
60
61	greg	1.1	extern long nrays; /* number of rays traced */
62
63			#define MAXDIV 32 /* maximum sample size */
64
65			#define pixjitter() (.5+dstrpix*(.5-frandom()))
66
67	greg	1.11	double pixvalue();
68	greg	1.1
69	greg	1.11
70	greg	1.1	quit(code) /* quit program */
71			int code;
72			{
73			if (code \|\| ralrm > 0) /* report status */
74			report();
75
76			exit(code);
77			}
78
79
80	greg	1.24	#ifdef BSD
81	greg	1.1	report() /* report progress */
82			{
83			struct rusage rubuf;
84			double t;
85
86			getrusage(RUSAGE_SELF, &rubuf);
87			t = (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
88			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
89			getrusage(RUSAGE_CHILDREN, &rubuf);
90			t += (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
91			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
92
93			sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f CPU hours\n",
94			nrays, pctdone, t/3600.0);
95	greg	1.24	eputs(errmsg);
96			tlastrept = time((long *)0);
97			}
98	greg	1.1	#else
99	greg	1.24	report() /* report progress */
100			{
101	greg	1.14	signal(SIGALRM, report);
102	greg	1.24	tlastrept = time((long *)0);
103			sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f hours\n",
104			nrays, pctdone, (tlastrept-tstart)/3600.0);
105	greg	1.1	eputs(errmsg);
106			}
107	greg	1.24	#endif
108	greg	1.1
109
110	greg	1.11	render(zfile, oldfile) /* render the scene */
111			char zfile, oldfile;
112	greg	1.1	{
113	greg	1.16	extern long lseek();
114	greg	1.1	COLOR scanbar[MAXDIV+1]; / scanline arrays of pixel values */
115	greg	1.11	float zbar[MAXDIV+1]; / z values */
116	greg	1.1	int ypos; /* current scanline */
117	greg	1.15	int ystep; /* current y step size */
118	greg	1.16	int zfd;
119	greg	1.1	COLOR *colptr;
120	greg	1.11	float *zptr;
121	greg	1.1	register int i;
122	greg	1.10	/* check sampling */
123			if (psample < 1)
124	greg	1.1	psample = 1;
125	greg	1.10	else if (psample > MAXDIV)
126			psample = MAXDIV;
127	greg	1.9	/* allocate scanlines */
128	greg	1.1	for (i = 0; i <= psample; i++) {
129	greg	1.12	scanbar[i] = (COLOR )malloc(hresolusizeof(COLOR));
130	greg	1.1	if (scanbar[i] == NULL)
131	greg	1.11	goto memerr;
132	greg	1.1	}
133	greg	1.11	/* open z file */
134			if (zfile != NULL) {
135	greg	1.16	if ((zfd = open(zfile, O_WRONLY\|O_CREAT, 0666)) == -1) {
136	greg	1.11	sprintf(errmsg, "cannot open z file \"%s\"", zfile);
137			error(SYSTEM, errmsg);
138			}
139			for (i = 0; i <= psample; i++) {
140	greg	1.12	zbar[i] = (float )malloc(hresolusizeof(float));
141	greg	1.11	if (zbar[i] == NULL)
142			goto memerr;
143			}
144			} else {
145	greg	1.16	zfd = -1;
146	greg	1.11	for (i = 0; i <= psample; i++)
147			zbar[i] = NULL;
148			}
149	greg	1.1	/* write out boundaries */
150	greg	1.12	fputresolu(YMAJOR\|YDECR, hresolu, vresolu, stdout);
151	greg	1.10	/* recover file and compute first */
152	greg	1.11	i = salvage(oldfile);
153	greg	1.23	if (zfd != -1 && i > 0 &&
154			lseek(zfd, (long)ihresolusizeof(float), 0) == -1)
155	greg	1.11	error(SYSTEM, "z file seek error in render");
156	greg	1.24	pctdone = 100.0*i/vresolu;
157			if (ralrm > 0) /* report init stats */
158			report();
159	greg	1.12	ypos = vresolu-1 - i;
160			fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
161	greg	1.15	ystep = psample;
162	greg	1.10	/* compute scanlines */
163	greg	1.15	for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
164			/* bottom adjust? */
165			if (ypos < 0) {
166			ystep += ypos;
167			ypos = 0;
168			}
169			colptr = scanbar[ystep]; /* move base to top */
170			scanbar[ystep] = scanbar[0];
171	greg	1.1	scanbar[0] = colptr;
172	greg	1.15	zptr = zbar[ystep];
173			zbar[ystep] = zbar[0];
174	greg	1.11	zbar[0] = zptr;
175	greg	1.10	/* fill base line */
176	greg	1.12	fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
177	greg	1.10	/* fill bar */
178	greg	1.15	fillscanbar(scanbar, zbar, hresolu, ypos, ystep);
179	greg	1.10	/* write it out */
180	greg	1.15	for (i = ystep; i > 0; i--) {
181	greg	1.17	if (zfd != -1 && write(zfd, (char *)zbar[i],
182			hresolu*sizeof(float))
183	greg	1.16	< hresolu*sizeof(float))
184	greg	1.1	goto writerr;
185	greg	1.17	if (fwritescan(scanbar[i], hresolu, stdout) < 0)
186	greg	1.11	goto writerr;
187			}
188	greg	1.1	if (fflush(stdout) == EOF)
189			goto writerr;
190	greg	1.24	/* record progress */
191			pctdone = 100.0*(vresolu-1-ypos)/vresolu;
192			if (ralrm > 0 && time((long *)0) >= tlastrept+ralrm)
193			report();
194	greg	1.1	}
195	greg	1.11	/* clean up */
196	greg	1.16	if (zfd != -1) {
197	greg	1.17	if (write(zfd, (char )zbar[0], hresolusizeof(float))
198	greg	1.16	< hresolu*sizeof(float))
199	greg	1.11	goto writerr;
200	greg	1.20	if (close(zfd) == -1)
201			goto writerr;
202	greg	1.11	for (i = 0; i <= psample; i++)
203			free((char *)zbar[i]);
204			}
205	greg	1.15	fwritescan(scanbar[0], hresolu, stdout);
206	greg	1.10	if (fflush(stdout) == EOF)
207			goto writerr;
208	greg	1.1	for (i = 0; i <= psample; i++)
209			free((char *)scanbar[i]);
210	greg	1.11	pctdone = 100.0;
211	greg	1.1	return;
212			writerr:
213			error(SYSTEM, "write error in render");
214	greg	1.11	memerr:
215			error(SYSTEM, "out of memory in render");
216	greg	1.1	}
217
218
219	greg	1.11	fillscanline(scanline, zline, xres, y, xstep) /* fill scan line at y */
220	greg	1.1	register COLOR *scanline;
221	greg	1.11	register float *zline;
222	greg	1.9	int xres, y, xstep;
223	greg	1.1	{
224			int b = xstep;
225	greg	1.11	double z;
226	greg	1.1	register int i;
227
228	greg	1.11	z = pixvalue(scanline[0], 0, y);
229			if (zline) zline[0] = z;
230	greg	1.1
231	greg	1.15	for (i = xstep; i < xres-1+xstep; i += xstep) {
232			if (i >= xres) {
233			xstep += xres-1-i;
234			i = xres-1;
235			}
236	greg	1.11	z = pixvalue(scanline[i], i, y);
237			if (zline) zline[i] = z;
238	greg	1.1
239	greg	1.11	b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
240			i-xstep, y, xstep, 0, b/2);
241	greg	1.1	}
242			}
243
244
245	greg	1.11	fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
246	greg	1.1	register COLOR *scanbar[];
247	greg	1.11	register float *zbar[];
248	greg	1.9	int xres, y, ysize;
249	greg	1.1	{
250			COLOR vline[MAXDIV+1];
251	greg	1.11	float zline[MAXDIV+1];
252	greg	1.1	int b = ysize;
253			register int i, j;
254
255	greg	1.8	for (i = 0; i < xres; i++) {
256	greg	1.1
257			copycolor(vline[0], scanbar[0][i]);
258			copycolor(vline[ysize], scanbar[ysize][i]);
259	greg	1.11	if (zbar[0]) {
260			zline[0] = zbar[0][i];
261			zline[ysize] = zbar[ysize][i];
262			}
263	greg	1.1
264	greg	1.11	b = fillsample(vline, zbar[0] ? zline : NULL,
265			i, y, 0, ysize, b/2);
266	greg	1.1
267			for (j = 1; j < ysize; j++)
268			copycolor(scanbar[j][i], vline[j]);
269	greg	1.11	if (zbar[0])
270			for (j = 1; j < ysize; j++)
271			zbar[j][i] = zline[j];
272	greg	1.1	}
273			}
274
275
276			int
277	greg	1.11	fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
278	greg	1.1	register COLOR *colline;
279	greg	1.11	register float *zline;
280	greg	1.1	int x, y;
281			int xlen, ylen;
282			int b;
283			{
284	greg	1.11	extern double fabs();
285	greg	1.1	double ratio;
286	greg	1.11	double z;
287	greg	1.1	COLOR ctmp;
288			int ncut;
289			register int len;
290
291			if (xlen > 0) /* x or y length is zero */
292			len = xlen;
293			else
294			len = ylen;
295
296			if (len <= 1) /* limit recursion */
297			return(0);
298
299	greg	1.11	if (b > 0
300			\|\| (zline && 2.fabs(zline[0]-zline[len]) > maxdiff(zline[0]+zline[len]))
301			\|\| bigdiff(colline[0], colline[len], maxdiff)) {
302	greg	1.1
303	greg	1.11	z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
304			if (zline) zline[len>>1] = z;
305	greg	1.1	ncut = 1;
306
307			} else { /* interpolate */
308
309			copycolor(colline[len>>1], colline[len]);
310			ratio = (double)(len>>1) / len;
311			scalecolor(colline[len>>1], ratio);
312	greg	1.11	if (zline) zline[len>>1] = zline[len] * ratio;
313			ratio = 1.0 - ratio;
314	greg	1.1	copycolor(ctmp, colline[0]);
315			scalecolor(ctmp, ratio);
316			addcolor(colline[len>>1], ctmp);
317	greg	1.11	if (zline) zline[len>>1] += zline[0] * ratio;
318	greg	1.1	ncut = 0;
319			}
320			/* recurse */
321	greg	1.11	ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
322	greg	1.1
323	greg	1.11	ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
324			x+(xlen>>1), y+(ylen>>1),
325			xlen-(xlen>>1), ylen-(ylen>>1), b/2);
326	greg	1.1
327			return(ncut);
328			}
329
330
331	greg	1.11	double
332	greg	1.1	pixvalue(col, x, y) /* compute pixel value */
333			COLOR col; /* returned color */
334			int x, y; /* pixel position */
335			{
336			static RAY thisray; /* our ray for this pixel */
337
338	greg	1.22	if (viewray(thisray.rorg, thisray.rdir, &ourview,
339			(x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) {
340			setcolor(col, 0.0, 0.0, 0.0);
341			return(0.0);
342			}
343	greg	1.1
344			rayorigin(&thisray, NULL, PRIMARY, 1.0);
345
346			rayvalue(&thisray); /* trace ray */
347
348			copycolor(col, thisray.rcol); /* return color */
349	greg	1.11
350	greg	1.20	return(thisray.rt); /* return distance */
351	greg	1.1	}
352
353
354			int
355			salvage(oldfile) /* salvage scanlines from killed program */
356			char *oldfile;
357			{
358			COLR *scanline;
359			FILE *fp;
360			int x, y;
361
362			if (oldfile == NULL)
363			return(0);
364	greg	1.9
365			if ((fp = fopen(oldfile, "r")) == NULL) {
366	greg	1.1	sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
367			error(WARNING, errmsg);
368			return(0);
369			}
370			/* discard header */
371			getheader(fp, NULL);
372			/* get picture size */
373	greg	1.7	if (fgetresolu(&x, &y, fp) != (YMAJOR\|YDECR)) {
374	greg	1.2	sprintf(errmsg, "bad recover file \"%s\"", oldfile);
375			error(WARNING, errmsg);
376	greg	1.1	fclose(fp);
377			return(0);
378			}
379
380	greg	1.12	if (x != hresolu \|\| y != vresolu) {
381	greg	1.1	sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
382			oldfile);
383			error(USER, errmsg);
384			}
385
386	greg	1.12	scanline = (COLR )malloc(hresolusizeof(COLR));
387	greg	1.1	if (scanline == NULL)
388			error(SYSTEM, "out of memory in salvage");
389	greg	1.12	for (y = 0; y < vresolu; y++) {
390			if (freadcolrs(scanline, hresolu, fp) < 0)
391	greg	1.1	break;
392	greg	1.12	if (fwritecolrs(scanline, hresolu, stdout) < 0)
393	greg	1.1	goto writerr;
394			}
395			if (fflush(stdout) == EOF)
396			goto writerr;
397			free((char *)scanline);
398			fclose(fp);
399			unlink(oldfile);
400			return(y);
401			writerr:
402			error(SYSTEM, "write error in salvage");
403			}