src/rt/rpict.c

/* Copyright (c) 1986 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>
#endif

#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 */

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);
}


report()                /* report progress */
{
#ifdef BSD
        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);
#else
        sprintf(errmsg, "%ld rays, %4.2f%% done\n", nrays, pctdone);
#endif
        eputs(errmsg);

        if (ralrm > 0)
                alarm(ralrm);
}


render(zfile, oldfile)                          /* render the scene */
char  *zfile, *oldfile;
{
        COLOR  *scanbar[MAXDIV+1];      /* scanline arrays of pixel values */
        float  *zbar[MAXDIV+1];         /* z values */
        int  ypos;                      /* current scanline */
        FILE  *zfp;
        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 ((zfp = fopen(zfile, "a+")) == NULL) {
                        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 {
                zfp = NULL;
                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 (zfp != NULL && fseek(zfp, (long)i*hresolu*sizeof(float), 0) == EOF)
                error(SYSTEM, "z file seek error in render");
        ypos = vresolu-1 - i;
        fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
                                                /* compute scanlines */
        for (ypos -= psample; ypos >= 0; ypos -= psample) {
        
                pctdone = 100.0*(vresolu-ypos-psample)/vresolu;

                colptr = scanbar[psample];              /* move base to top */
                scanbar[psample] = scanbar[0];
                scanbar[0] = colptr;
                zptr = zbar[psample];
                zbar[psample] = zbar[0];
                zbar[0] = zptr;
                                                        /* fill base line */
                fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
                                                        /* fill bar */
                fillscanbar(scanbar, zbar, hresolu, ypos, psample);
                                                        /* write it out */
                for (i = psample; i > 0; i--) {
                        if (zfp != NULL && fwrite(zbar[i],sizeof(float),hresolu,zfp) != hresolu)
                                goto writerr;
                        if (fwritescan(scanbar[i],hresolu,stdout) < 0)
                                goto writerr;
                }
                if (zfp != NULL && fflush(zfp) == EOF)
                        goto writerr;
                if (fflush(stdout) == EOF)
                        goto writerr;
        }
                                                /* compute residual */
        colptr = scanbar[psample];
        scanbar[psample] = scanbar[0];
        scanbar[0] = colptr;
        zptr = zbar[psample];
        zbar[psample] = zbar[0];
        zbar[0] = zptr;
        if (ypos > -psample) {
                fillscanline(scanbar[-ypos], zbar[-ypos], hresolu, 0, psample);
                fillscanbar(scanbar-ypos, zbar-ypos, hresolu, 0, psample+ypos);
        }
        for (i = psample; i+ypos >= 0; i--) {
                if (zfp != NULL && fwrite(zbar[i],sizeof(float),hresolu,zfp) != hresolu)
                        goto writerr;
                if (fwritescan(scanbar[i], hresolu, stdout) < 0)
                        goto writerr;
        }
                                                /* clean up */
        if (zfp != NULL) {
                if (fclose(zfp) == EOF)
                        goto writerr;
                for (i = 0; i <= psample; i++)
                        free((char *)zbar[i]);
        }
        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; i += xstep) {
        
                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);
        }
        if (i-xstep < xres-1) {
                z = pixvalue(scanline[xres-1], xres-1, y);
                if (zline) zline[xres-1] = z;
                fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
                                i-xstep, y, xres-1-(i-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;
        double  z;
        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 */

        viewray(thisray.rorg, thisray.rdir, &ourview,
                        (x+pixjitter())/hresolu, (y+pixjitter())/vresolu);

        rayorigin(&thisray, NULL, PRIMARY, 1.0);
        
        rayvalue(&thisray);                     /* trace ray */

        copycolor(col, thisray.rcol);           /* return color */
        
        return(thisray.rot);                    /* 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:	1.13
Committed:	Tue Jan 9 09:07:29 1990 UTC (34 years, 3 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.12:	+1 -0 lines
Log Message:	added option for pixel aspect ratio
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1986 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 "view.h"
21
22			#include "random.h"
23
24	greg	1.12	VIEW ourview = STDVIEW; /* view parameters */
25			int hresolu = 512; /* horizontal resolution */
26			int vresolu = 512; /* vertical resolution */
27	greg	1.13	double pixaspect = 1.0; /* pixel aspect ratio */
28	greg	1.1
29			int psample = 4; /* pixel sample size */
30			double maxdiff = .05; /* max. difference for interpolation */
31	greg	1.3	double dstrpix = 0.67; /* square pixel distribution */
32	greg	1.1
33			double dstrsrc = 0.0; /* square source distribution */
34	greg	1.4	double shadthresh = .05; /* shadow threshold */
35	greg	1.5	double shadcert = .5; /* shadow certainty */
36	greg	1.1
37			int maxdepth = 6; /* maximum recursion depth */
38			double minweight = 5e-3; /* minimum ray weight */
39
40			COLOR ambval = BLKCOLOR; /* ambient value */
41			double ambacc = 0.2; /* ambient accuracy */
42	greg	1.6	int ambres = 32; /* ambient resolution */
43	greg	1.1	int ambdiv = 128; /* ambient divisions */
44			int ambssamp = 0; /* ambient super-samples */
45			int ambounce = 0; /* ambient bounces */
46			char amblist[128]; / ambient include/exclude list */
47			int ambincl = -1; /* include == 1, exclude == 0 */
48
49			int ralrm = 0; /* seconds between reports */
50
51			double pctdone = 0.0; /* percentage done */
52
53			extern long nrays; /* number of rays traced */
54
55			#define MAXDIV 32 /* maximum sample size */
56
57			#define pixjitter() (.5+dstrpix*(.5-frandom()))
58
59	greg	1.11	double pixvalue();
60	greg	1.1
61	greg	1.11
62	greg	1.1	quit(code) /* quit program */
63			int code;
64			{
65			if (code \|\| ralrm > 0) /* report status */
66			report();
67
68			exit(code);
69			}
70
71
72			report() /* report progress */
73			{
74			#ifdef BSD
75			struct rusage rubuf;
76			double t;
77
78			getrusage(RUSAGE_SELF, &rubuf);
79			t = (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
80			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
81			getrusage(RUSAGE_CHILDREN, &rubuf);
82			t += (rubuf.ru_utime.tv_usec + rubuf.ru_stime.tv_usec) / 1e6;
83			t += rubuf.ru_utime.tv_sec + rubuf.ru_stime.tv_sec;
84
85			sprintf(errmsg, "%ld rays, %4.2f%% done after %5.4f CPU hours\n",
86			nrays, pctdone, t/3600.0);
87			#else
88			sprintf(errmsg, "%ld rays, %4.2f%% done\n", nrays, pctdone);
89			#endif
90			eputs(errmsg);
91
92			if (ralrm > 0)
93			alarm(ralrm);
94			}
95
96
97	greg	1.11	render(zfile, oldfile) /* render the scene */
98			char zfile, oldfile;
99	greg	1.1	{
100			COLOR scanbar[MAXDIV+1]; / scanline arrays of pixel values */
101	greg	1.11	float zbar[MAXDIV+1]; / z values */
102	greg	1.1	int ypos; /* current scanline */
103	greg	1.11	FILE *zfp;
104	greg	1.1	COLOR *colptr;
105	greg	1.11	float *zptr;
106	greg	1.1	register int i;
107	greg	1.10	/* check sampling */
108			if (psample < 1)
109	greg	1.1	psample = 1;
110	greg	1.10	else if (psample > MAXDIV)
111			psample = MAXDIV;
112	greg	1.9	/* allocate scanlines */
113	greg	1.1	for (i = 0; i <= psample; i++) {
114	greg	1.12	scanbar[i] = (COLOR )malloc(hresolusizeof(COLOR));
115	greg	1.1	if (scanbar[i] == NULL)
116	greg	1.11	goto memerr;
117	greg	1.1	}
118	greg	1.11	/* open z file */
119			if (zfile != NULL) {
120			if ((zfp = fopen(zfile, "a+")) == NULL) {
121			sprintf(errmsg, "cannot open z file \"%s\"", zfile);
122			error(SYSTEM, errmsg);
123			}
124			for (i = 0; i <= psample; i++) {
125	greg	1.12	zbar[i] = (float )malloc(hresolusizeof(float));
126	greg	1.11	if (zbar[i] == NULL)
127			goto memerr;
128			}
129			} else {
130			zfp = NULL;
131			for (i = 0; i <= psample; i++)
132			zbar[i] = NULL;
133			}
134	greg	1.1	/* write out boundaries */
135	greg	1.12	fputresolu(YMAJOR\|YDECR, hresolu, vresolu, stdout);
136	greg	1.10	/* recover file and compute first */
137	greg	1.11	i = salvage(oldfile);
138	greg	1.12	if (zfp != NULL && fseek(zfp, (long)ihresolusizeof(float), 0) == EOF)
139	greg	1.11	error(SYSTEM, "z file seek error in render");
140	greg	1.12	ypos = vresolu-1 - i;
141			fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
142	greg	1.10	/* compute scanlines */
143			for (ypos -= psample; ypos >= 0; ypos -= psample) {
144	greg	1.1
145	greg	1.12	pctdone = 100.0*(vresolu-ypos-psample)/vresolu;
146	greg	1.9
147			colptr = scanbar[psample]; /* move base to top */
148	greg	1.1	scanbar[psample] = scanbar[0];
149			scanbar[0] = colptr;
150	greg	1.11	zptr = zbar[psample];
151			zbar[psample] = zbar[0];
152			zbar[0] = zptr;
153	greg	1.10	/* fill base line */
154	greg	1.12	fillscanline(scanbar[0], zbar[0], hresolu, ypos, psample);
155	greg	1.10	/* fill bar */
156	greg	1.12	fillscanbar(scanbar, zbar, hresolu, ypos, psample);
157	greg	1.10	/* write it out */
158	greg	1.11	for (i = psample; i > 0; i--) {
159	greg	1.12	if (zfp != NULL && fwrite(zbar[i],sizeof(float),hresolu,zfp) != hresolu)
160	greg	1.1	goto writerr;
161	greg	1.12	if (fwritescan(scanbar[i],hresolu,stdout) < 0)
162	greg	1.11	goto writerr;
163			}
164			if (zfp != NULL && fflush(zfp) == EOF)
165			goto writerr;
166	greg	1.1	if (fflush(stdout) == EOF)
167			goto writerr;
168			}
169	greg	1.10	/* compute residual */
170			colptr = scanbar[psample];
171			scanbar[psample] = scanbar[0];
172			scanbar[0] = colptr;
173	greg	1.11	zptr = zbar[psample];
174			zbar[psample] = zbar[0];
175			zbar[0] = zptr;
176	greg	1.10	if (ypos > -psample) {
177	greg	1.12	fillscanline(scanbar[-ypos], zbar[-ypos], hresolu, 0, psample);
178			fillscanbar(scanbar-ypos, zbar-ypos, hresolu, 0, psample+ypos);
179	greg	1.10	}
180	greg	1.11	for (i = psample; i+ypos >= 0; i--) {
181	greg	1.12	if (zfp != NULL && fwrite(zbar[i],sizeof(float),hresolu,zfp) != hresolu)
182	greg	1.11	goto writerr;
183	greg	1.12	if (fwritescan(scanbar[i], hresolu, stdout) < 0)
184	greg	1.10	goto writerr;
185	greg	1.11	}
186			/* clean up */
187			if (zfp != NULL) {
188			if (fclose(zfp) == EOF)
189			goto writerr;
190			for (i = 0; i <= psample; i++)
191			free((char *)zbar[i]);
192			}
193	greg	1.10	if (fflush(stdout) == EOF)
194			goto writerr;
195	greg	1.1	for (i = 0; i <= psample; i++)
196			free((char *)scanbar[i]);
197	greg	1.11	pctdone = 100.0;
198	greg	1.1	return;
199			writerr:
200			error(SYSTEM, "write error in render");
201	greg	1.11	memerr:
202			error(SYSTEM, "out of memory in render");
203	greg	1.1	}
204
205
206	greg	1.11	fillscanline(scanline, zline, xres, y, xstep) /* fill scan line at y */
207	greg	1.1	register COLOR *scanline;
208	greg	1.11	register float *zline;
209	greg	1.9	int xres, y, xstep;
210	greg	1.1	{
211			int b = xstep;
212	greg	1.11	double z;
213	greg	1.1	register int i;
214
215	greg	1.11	z = pixvalue(scanline[0], 0, y);
216			if (zline) zline[0] = z;
217	greg	1.1
218	greg	1.9	for (i = xstep; i < xres; i += xstep) {
219	greg	1.1
220	greg	1.11	z = pixvalue(scanline[i], i, y);
221			if (zline) zline[i] = z;
222	greg	1.1
223	greg	1.11	b = fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
224			i-xstep, y, xstep, 0, b/2);
225	greg	1.10	}
226			if (i-xstep < xres-1) {
227	greg	1.11	z = pixvalue(scanline[xres-1], xres-1, y);
228			if (zline) zline[xres-1] = z;
229			fillsample(scanline+i-xstep, zline ? zline+i-xstep : NULL,
230			i-xstep, y, xres-1-(i-xstep), 0, b/2);
231	greg	1.1	}
232			}
233
234
235	greg	1.11	fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
236	greg	1.1	register COLOR *scanbar[];
237	greg	1.11	register float *zbar[];
238	greg	1.9	int xres, y, ysize;
239	greg	1.1	{
240			COLOR vline[MAXDIV+1];
241	greg	1.11	float zline[MAXDIV+1];
242	greg	1.1	int b = ysize;
243	greg	1.11	double z;
244	greg	1.1	register int i, j;
245
246	greg	1.8	for (i = 0; i < xres; i++) {
247	greg	1.1
248			copycolor(vline[0], scanbar[0][i]);
249			copycolor(vline[ysize], scanbar[ysize][i]);
250	greg	1.11	if (zbar[0]) {
251			zline[0] = zbar[0][i];
252			zline[ysize] = zbar[ysize][i];
253			}
254	greg	1.1
255	greg	1.11	b = fillsample(vline, zbar[0] ? zline : NULL,
256			i, y, 0, ysize, b/2);
257	greg	1.1
258			for (j = 1; j < ysize; j++)
259			copycolor(scanbar[j][i], vline[j]);
260	greg	1.11	if (zbar[0])
261			for (j = 1; j < ysize; j++)
262			zbar[j][i] = zline[j];
263	greg	1.1	}
264			}
265
266
267			int
268	greg	1.11	fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
269	greg	1.1	register COLOR *colline;
270	greg	1.11	register float *zline;
271	greg	1.1	int x, y;
272			int xlen, ylen;
273			int b;
274			{
275	greg	1.11	extern double fabs();
276	greg	1.1	double ratio;
277	greg	1.11	double z;
278	greg	1.1	COLOR ctmp;
279			int ncut;
280			register int len;
281
282			if (xlen > 0) /* x or y length is zero */
283			len = xlen;
284			else
285			len = ylen;
286
287			if (len <= 1) /* limit recursion */
288			return(0);
289
290	greg	1.11	if (b > 0
291			\|\| (zline && 2.fabs(zline[0]-zline[len]) > maxdiff(zline[0]+zline[len]))
292			\|\| bigdiff(colline[0], colline[len], maxdiff)) {
293	greg	1.1
294	greg	1.11	z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
295			if (zline) zline[len>>1] = z;
296	greg	1.1	ncut = 1;
297
298			} else { /* interpolate */
299
300			copycolor(colline[len>>1], colline[len]);
301			ratio = (double)(len>>1) / len;
302			scalecolor(colline[len>>1], ratio);
303	greg	1.11	if (zline) zline[len>>1] = zline[len] * ratio;
304			ratio = 1.0 - ratio;
305	greg	1.1	copycolor(ctmp, colline[0]);
306			scalecolor(ctmp, ratio);
307			addcolor(colline[len>>1], ctmp);
308	greg	1.11	if (zline) zline[len>>1] += zline[0] * ratio;
309	greg	1.1	ncut = 0;
310			}
311			/* recurse */
312	greg	1.11	ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
313	greg	1.1
314	greg	1.11	ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
315			x+(xlen>>1), y+(ylen>>1),
316			xlen-(xlen>>1), ylen-(ylen>>1), b/2);
317	greg	1.1
318			return(ncut);
319			}
320
321
322	greg	1.11	double
323	greg	1.1	pixvalue(col, x, y) /* compute pixel value */
324			COLOR col; /* returned color */
325			int x, y; /* pixel position */
326			{
327			static RAY thisray; /* our ray for this pixel */
328
329	greg	1.12	viewray(thisray.rorg, thisray.rdir, &ourview,
330			(x+pixjitter())/hresolu, (y+pixjitter())/vresolu);
331	greg	1.1
332			rayorigin(&thisray, NULL, PRIMARY, 1.0);
333
334			rayvalue(&thisray); /* trace ray */
335
336			copycolor(col, thisray.rcol); /* return color */
337	greg	1.11
338			return(thisray.rot); /* return distance */
339	greg	1.1	}
340
341
342			int
343			salvage(oldfile) /* salvage scanlines from killed program */
344			char *oldfile;
345			{
346			COLR *scanline;
347			FILE *fp;
348			int x, y;
349
350			if (oldfile == NULL)
351			return(0);
352	greg	1.9
353			if ((fp = fopen(oldfile, "r")) == NULL) {
354	greg	1.1	sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
355			error(WARNING, errmsg);
356			return(0);
357			}
358			/* discard header */
359			getheader(fp, NULL);
360			/* get picture size */
361	greg	1.7	if (fgetresolu(&x, &y, fp) != (YMAJOR\|YDECR)) {
362	greg	1.2	sprintf(errmsg, "bad recover file \"%s\"", oldfile);
363			error(WARNING, errmsg);
364	greg	1.1	fclose(fp);
365			return(0);
366			}
367
368	greg	1.12	if (x != hresolu \|\| y != vresolu) {
369	greg	1.1	sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
370			oldfile);
371			error(USER, errmsg);
372			}
373
374	greg	1.12	scanline = (COLR )malloc(hresolusizeof(COLR));
375	greg	1.1	if (scanline == NULL)
376			error(SYSTEM, "out of memory in salvage");
377	greg	1.12	for (y = 0; y < vresolu; y++) {
378			if (freadcolrs(scanline, hresolu, fp) < 0)
379	greg	1.1	break;
380	greg	1.12	if (fwritecolrs(scanline, hresolu, stdout) < 0)
381	greg	1.1	goto writerr;
382			}
383			if (fflush(stdout) == EOF)
384			goto writerr;
385			free((char *)scanline);
386			fclose(fp);
387			unlink(oldfile);
388			return(y);
389			writerr:
390			error(SYSTEM, "write error in salvage");
391			}