src/hd/rhcopy.c

/* Copyright (c) 1998 Silicon Graphics, Inc. */

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

/*
 * Copy data into a holodeck file
 */

#include "holo.h"
#include "view.h"
#include "resolu.h"

#ifndef BKBSIZE
#define BKBSIZE         256             /* beam clump size (kilobytes) */
#endif

int     checkdepth = 1;         /* check depth (!-f option)? */
int     checkrepeats = 0;       /* check for repeats (-c option)? */
int     frompicz;               /* input from pictures & depth-buffers? */
int     noutsects;              /* number of output sections */
char    obstr, unobstr;         /* flag pointer values */

char    *progname;              /* global argv[0] */


main(argc, argv)
int     argc;
char    *argv[];
{
        int     i;

        progname = argv[0];
        frompicz = -1;
        for (i = 2; i < argc && argv[i][0] == '-'; i++)
                switch (argv[i][1]) {
                case 'u':
                        checkrepeats = 1;
                        break;
                case 'd':
                        checkdepth = 0;
                        break;
                case 'h':
                        frompicz = 0;
                        break;
                case 'p':
                        frompicz = 1;
                        break;
                default:
                        goto userr;
                }
        if (i >= argc || frompicz < 0)
                goto userr;
        if (frompicz && (argc-i)%2)
                goto userr;
        noutsects = openholo(argv[1], 1);
        if (frompicz) {
                for ( ; i < argc; i += 2)
                        addpicz(argv[i], argv[i+1]);
        } else {
                if (BKBSIZE*1024*1.5 > hdcachesize)
                        hdcachesize = BKBSIZE*1024*1.5;
                for ( ; i < argc; i++)
                        addholo(argv[i]);
        }
        quit(0);
userr:
        fprintf(stderr, "Usage: %s output.hdk [-u][-d] -h inp1.hdk ..\n",
                        progname);
        fprintf(stderr, "   Or: %s output.hdk [-u][-d] -p inp1.pic inp1.zbf ..\n",
                        progname);
        exit(1);
}


#define H_BADF  01
#define H_OBST  02
#define H_OBSF  04

int
holheadline(s, hf)              /* check holodeck header line */
register char   *s;
int     *hf;
{
        char    fmt[32];

        if (formatval(fmt, s)) {
                if (strcmp(fmt, HOLOFMT))
                        *hf |= H_BADF;
                else
                        *hf &= ~H_BADF;
                return(0);
        }
        if (!strncmp(s, "OBSTRUCTIONS=", 13)) {
                s += 13;
                while (*s == ' ') s++;
                if (*s == 't' | *s == 'T')
                        *hf |= H_OBST;
                else if (*s == 'f' | *s == 'F')
                        *hf |= H_OBSF;
                else
                        error(WARNING, "bad OBSTRUCTIONS value in holodeck");
                return(0);
        }
        return(0);
}

int
openholo(fname, append)         /* open existing holodeck file for i/o */
char    *fname;
int     append;
{
        extern long     ftell();
        FILE    *fp;
        int     fd;
        int     hflags = 0;
        long    nextloc;
        int     n;
                                        /* open holodeck file */
        if ((fp = fopen(fname, append ? "r+" : "r")) == NULL) {
                sprintf(errmsg, "cannot open \"%s\" for %s", fname,
                                append ? "appending" : "reading");
                error(SYSTEM, errmsg);
        }
                                        /* check header and magic number */
        if (getheader(fp, holheadline, &hflags) < 0 ||
                        hflags&H_BADF || getw(fp) != HOLOMAGIC) {
                sprintf(errmsg, "file \"%s\" not in holodeck format", fname);
                error(USER, errmsg);
        }
        fd = dup(fileno(fp));                   /* dup file handle */
        nextloc = ftell(fp);                    /* get stdio position */
        fclose(fp);                             /* done with stdio */
        for (n = 0; nextloc > 0L; n++) {        /* initialize each section */
                lseek(fd, nextloc, 0);
                read(fd, (char *)&nextloc, sizeof(nextloc));
                hdinit(fd, NULL)->priv = hflags&H_OBST ? &obstr :
                                hflags&H_OBSF ? &unobstr : (char *)NULL;
        }
        return(n);
}

#undef H_BADF
#undef H_OBST
#undef H_OBSF


addray(ro, rd, d, cv)           /* add a ray to our output holodeck */
FVECT   ro, rd;
double  d;
COLR    cv;
{
        int     sn, bi, n;
        register HOLO   *hp;
        GCOORD  gc[2];
        BYTE    rr[2][2];
        BEAM    *bp;
        double  d0, d1;
        unsigned        dc;
        register RAYVAL *rv;
                                /* check each output section */
        for (sn = noutsects; sn--; ) {
                hp = hdlist[sn];
                d0 = hdinter(gc, rr, &d1, hp, ro, rd);
                if (d <= d0 || d1 < -0.001)
                        continue;       /* missed section */
                if (checkdepth) {               /* check depth */
                        if (hp->priv == &obstr && d0 < -0.001)
                                continue;       /* ray starts too late */
                        if (hp->priv == &unobstr && d < 0.999*d1)
                                continue;       /* ray ends too soon */
                }
                dc = hdcode(hp, d-d0);
                bi = hdbindex(hp, gc);          /* check for duplicates */
                if (checkrepeats && (bp = hdgetbeam(hp, bi)) != NULL) {
                        for (n = bp->nrm, rv = hdbray(bp); n--; rv++)
                                if (rv->d == dc &&
                                                rv->r[0][0] == rr[0][0] &&
                                                rv->r[0][1] == rr[0][1] &&
                                                rv->r[1][0] == rr[1][0] &&
                                                rv->r[1][1] == rr[1][1])
                                        break;
                        if (n >= 0)
                                continue;       /* found a matching ray */
                }
                rv = hdnewrays(hp, bi, 1);
                rv->d = dc;
                rv->r[0][0] = rr[0][0]; rv->r[0][1] = rr[0][1];
                rv->r[1][0] = rr[1][0]; rv->r[1][1] = rr[1][1];
                copycolr(rv->v, cv);
        }
}


addbeam(bp, hb)                 /* add a beam to our output holodeck */
register BEAM   *bp;
register HDBEAMI        *hb;
{
        GCOORD  gc[2];
        FVECT   ro, rd;
        double  d;
        register int    k;
                                        /* get beam coordinates */
        hdbcoord(gc, hb->h, hb->b);
                                        /* add each ray to output */
        for (k = bp->nrm; k--; ) {
                d = hdray(ro, rd, hb->h, gc, hdbray(bp)[k].r);
                if (hb->h->priv == &unobstr)
                        VSUM(ro, ro, rd, d);
                else
                        d = 0.;
                d = hddepth(hb->h, hdbray(bp)[k].d) - d;
                addray(ro, rd, d, hdbray(bp)[k].v);
        }
        hdfreebeam(hb->h, hb->b);       /* free the beam */
}


addholo(hdf)                    /* add a holodeck file */
char    *hdf;
{
        int     fd;
                                        /* open the holodeck for reading */
        openholo(hdf, 0);
        fd = hdlist[noutsects]->fd;     /* remember the file handle */
        while (hdlist[noutsects] != NULL) {     /* load each section */
                                                        /* clump the beams */
                clumpbeams(hdlist[noutsects], 0, BKBSIZE*1024, addbeam);
                hddone(hdlist[noutsects]);              /* free the section */
        }
        close(fd);                      /* close input file */
}


struct phead {
        VIEW    vw;
        double  expos;
        short   gotview;
        short   badfmt;
        short   altprims;
};


int
picheadline(s, ph)              /* process picture header line */
char    *s;
struct phead    *ph;
{
        char    fmt[32];

        if (formatval(fmt, s)) {
                ph->badfmt = strcmp(fmt, COLRFMT);
                return(0);
        }
        if (isprims(s)) {
                ph->altprims++;         /* don't want to deal with this */
                return(0);
        }
        if (isexpos(s)) {
                ph->expos *= exposval(s);
                return(0);
        }
        if (isview(s)) {
                ph->gotview += sscanview(&ph->vw, s);
                return(0);
        }
        return(0);
}


addpicz(pcf, zbf)               /* add a picture + depth-buffer */
char    *pcf, *zbf;
{
        FILE    *pfp;
        int     zfd;
        COLR    *cscn;
        float   *zscn;
        struct phead    phd;
        int     eshft;
        double  emult;
        RESOLU  prs;
        FLOAT   vl[2];
        FVECT   ro, rd;
        double  aftd;
        COLOR   ctmp;
        int     j;
        register int    i;
                                /* open files */
        if ((pfp = fopen(pcf, "r")) == NULL) {
                sprintf(errmsg, "cannot open picture file \"%s\"", pcf);
                error(SYSTEM, pcf);
        }
        if ((zfd = open(zbf, O_RDONLY)) < 0) {
                sprintf(errmsg, "cannot open depth file \"%s\"", zbf);
                error(SYSTEM, pcf);
        }
                                /* load picture header */
        copystruct(&phd.vw, &stdview);
        phd.expos = 1.0;
        phd.badfmt = phd.gotview = phd.altprims = 0;
        if (getheader(pfp, picheadline, &phd) < 0 ||
                        phd.badfmt || !fgetsresolu(&prs, pfp)) {
                sprintf(errmsg, "bad format for picture file \"%s\"", pcf);
                error(USER, errmsg);
        }
        if (!phd.gotview || setview(&phd.vw) != NULL) {
                sprintf(errmsg, "missing/illegal view in picture \"%s\"",
                                pcf);
                error(USER, errmsg);
        }
        if (phd.altprims) {
                sprintf(errmsg, "ignoring primary values in picture \"%s\"",
                                pcf);
                error(WARNING, errmsg);
        }
                                /* figure out what to do about exposure */
        if (phd.expos < 0.99 | phd.expos > 1.01) {
                emult = -log(phd.expos)/log(2.);
                eshft = emult >= 0. ? emult+.5 : emult-.5;
                emult -= (double)eshft;
                if (emult <= 0.01 & emult >= -0.01)
                        emult = -1.;
                else {
                        emult = 1./phd.expos;
                        eshft = 0;
                }
        } else {
                emult = -1.;
                eshft = 0;
        }
                                /* allocate buffers */
        cscn = (COLR *)malloc(scanlen(&prs)*sizeof(COLR));
        zscn = (float *)malloc(scanlen(&prs)*sizeof(float));
        if (cscn == NULL | zscn == NULL)
                error(SYSTEM, "out of memory in addpicz");
                                /* read and process each scanline */
        for (j = 0; j < numscans(&prs); j++) {
                i = scanlen(&prs);                      /* read colrs */
                if (freadcolrs(cscn, i, pfp) < 0) {
                        sprintf(errmsg, "error reading picture \"%s\"", pcf);
                        error(USER, errmsg);
                }
                if (eshft)                              /* shift exposure */
                        shiftcolrs(cscn, i, eshft);
                i *= sizeof(float);                     /* read depth */
                if (read(zfd, (char *)zscn, i) != i) {
                        sprintf(errmsg, "error reading depth file \"%s\"", zbf);
                        error(USER, errmsg);
                }
                for (i = scanlen(&prs); i--; ) {        /* do each pixel */
                        pix2loc(vl, &prs, i, j);
                        aftd = viewray(ro, rd, &phd.vw, vl[0], vl[1]);
                        if (aftd < -FTINY)
                                continue;               /* off view */
                        if (aftd > FTINY && zscn[i] > aftd)
                                continue;               /* aft clipped */
                        if (emult > 0.) {               /* whatta pain */
                                colr_color(ctmp, cscn[i]);
                                scalecolor(ctmp, emult);
                                setcolr(cscn[i], colval(ctmp,RED),
                                        colval(ctmp,GRN), colval(ctmp,BLU));
                        }
                        addray(ro, rd, (double)zscn[i], cscn[i]);
                }
        }
                                /* write output */
        hdsync(NULL, 1);
                                /* clean up */
        free((char *)cscn);
        free((char *)zscn);
        fclose(pfp);
        close(zfd);
}


eputs(s)                        /* put error message to stderr */
register char  *s;
{
        static int  midline = 0;

        if (!*s)
                return;
        if (!midline++) {       /* prepend line with program name */
                fputs(progname, stderr);
                fputs(": ", stderr);
        }
        fputs(s, stderr);
        if (s[strlen(s)-1] == '\n') {
                fflush(stderr);
                midline = 0;
        }
}


quit(code)                      /* exit the program gracefully */
int     code;
{
        hdsync(NULL, 1);        /* write out any buffered data */
        exit(code);
}
Revision:	3.10
Committed:	Mon Nov 9 17:11:40 1998 UTC (25 years, 5 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 3.9:	+39 -44 lines
Log Message:	moved routines to clumpbeams.c and made rhcopy clump beams
#	User	Rev	Content
1	gwlarson	3.10	/* Copyright (c) 1998 Silicon Graphics, Inc. */
2	gregl	3.1
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ SGI";
5			#endif
6
7			/*
8			* Copy data into a holodeck file
9			*/
10
11			#include "holo.h"
12			#include "view.h"
13			#include "resolu.h"
14
15	gwlarson	3.10	#ifndef BKBSIZE
16			#define BKBSIZE 256 /* beam clump size (kilobytes) */
17	gregl	3.7	#endif
18
19	gregl	3.5	int checkdepth = 1; /* check depth (!-f option)? */
20			int checkrepeats = 0; /* check for repeats (-c option)? */
21	gregl	3.1	int frompicz; /* input from pictures & depth-buffers? */
22			int noutsects; /* number of output sections */
23	gregl	3.2	char obstr, unobstr; /* flag pointer values */
24	gregl	3.1
25			char progname; / global argv[0] */
26
27
28			main(argc, argv)
29			int argc;
30			char *argv[];
31			{
32			int i;
33
34			progname = argv[0];
35	gregl	3.5	frompicz = -1;
36			for (i = 2; i < argc && argv[i][0] == '-'; i++)
37			switch (argv[i][1]) {
38	gregl	3.8	case 'u':
39	gregl	3.5	checkrepeats = 1;
40			break;
41	gregl	3.8	case 'd':
42	gregl	3.5	checkdepth = 0;
43			break;
44			case 'h':
45			frompicz = 0;
46			break;
47			case 'p':
48			frompicz = 1;
49			break;
50			default:
51			goto userr;
52			}
53			if (i >= argc \|\| frompicz < 0)
54	gregl	3.1	goto userr;
55	gregl	3.5	if (frompicz && (argc-i)%2)
56	gregl	3.1	goto userr;
57			noutsects = openholo(argv[1], 1);
58	gwlarson	3.10	if (frompicz) {
59	gregl	3.5	for ( ; i < argc; i += 2)
60	gregl	3.1	addpicz(argv[i], argv[i+1]);
61	gwlarson	3.10	} else {
62			if (BKBSIZE10241.5 > hdcachesize)
63			hdcachesize = BKBSIZE10241.5;
64	gregl	3.5	for ( ; i < argc; i++)
65	gregl	3.1	addholo(argv[i]);
66	gwlarson	3.10	}
67	gregl	3.1	quit(0);
68			userr:
69	gregl	3.8	fprintf(stderr, "Usage: %s output.hdk [-u][-d] -h inp1.hdk ..\n",
70	gregl	3.1	progname);
71	gwlarson	3.10	fprintf(stderr, " Or: %s output.hdk [-u][-d] -p inp1.pic inp1.zbf ..\n",
72	gregl	3.5	progname);
73	gregl	3.1	exit(1);
74			}
75
76
77	gregl	3.2	#define H_BADF 01
78			#define H_OBST 02
79			#define H_OBSF 04
80
81	gwlarson	3.9	int
82	gregl	3.2	holheadline(s, hf) /* check holodeck header line */
83	gregl	3.1	register char *s;
84	gregl	3.2	int *hf;
85	gregl	3.1	{
86			char fmt[32];
87
88			if (formatval(fmt, s)) {
89	gregl	3.2	if (strcmp(fmt, HOLOFMT))
90			*hf \|= H_BADF;
91			else
92			*hf &= ~H_BADF;
93	gwlarson	3.9	return(0);
94	gregl	3.1	}
95			if (!strncmp(s, "OBSTRUCTIONS=", 13)) {
96			s += 13;
97			while (*s == ' ') s++;
98			if (s == 't' \| s == 'T')
99	gregl	3.2	*hf \|= H_OBST;
100	gregl	3.1	else if (s == 'f' \| s == 'F')
101	gregl	3.2	*hf \|= H_OBSF;
102	gregl	3.1	else
103			error(WARNING, "bad OBSTRUCTIONS value in holodeck");
104	gwlarson	3.9	return(0);
105	gregl	3.1	}
106	gwlarson	3.9	return(0);
107	gregl	3.1	}
108
109			int
110			openholo(fname, append) /* open existing holodeck file for i/o */
111			char *fname;
112			int append;
113			{
114			extern long ftell();
115			FILE *fp;
116			int fd;
117	gregl	3.2	int hflags = 0;
118	gregl	3.3	long nextloc;
119	gregl	3.1	int n;
120			/* open holodeck file */
121			if ((fp = fopen(fname, append ? "r+" : "r")) == NULL) {
122			sprintf(errmsg, "cannot open \"%s\" for %s", fname,
123			append ? "appending" : "reading");
124			error(SYSTEM, errmsg);
125			}
126			/* check header and magic number */
127	gregl	3.2	if (getheader(fp, holheadline, &hflags) < 0 \|\|
128			hflags&H_BADF \|\| getw(fp) != HOLOMAGIC) {
129	gregl	3.1	sprintf(errmsg, "file \"%s\" not in holodeck format", fname);
130			error(USER, errmsg);
131			}
132			fd = dup(fileno(fp)); /* dup file handle */
133			nextloc = ftell(fp); /* get stdio position */
134			fclose(fp); /* done with stdio */
135			for (n = 0; nextloc > 0L; n++) { /* initialize each section */
136	gregl	3.3	lseek(fd, nextloc, 0);
137	gregl	3.1	read(fd, (char *)&nextloc, sizeof(nextloc));
138	gregl	3.2	hdinit(fd, NULL)->priv = hflags&H_OBST ? &obstr :
139			hflags&H_OBSF ? &unobstr : (char *)NULL;
140	gregl	3.1	}
141			return(n);
142			}
143
144	gregl	3.2	#undef H_BADF
145			#undef H_OBST
146			#undef H_OBSF
147	gregl	3.1
148	gregl	3.2
149	gregl	3.1	addray(ro, rd, d, cv) /* add a ray to our output holodeck */
150			FVECT ro, rd;
151			double d;
152			COLR cv;
153			{
154	gregl	3.5	int sn, bi, n;
155	gregl	3.1	register HOLO *hp;
156			GCOORD gc[2];
157			BYTE rr[2][2];
158	gregl	3.5	BEAM *bp;
159	gregl	3.1	double d0, d1;
160	gregl	3.5	unsigned dc;
161	gregl	3.1	register RAYVAL *rv;
162			/* check each output section */
163			for (sn = noutsects; sn--; ) {
164			hp = hdlist[sn];
165			d0 = hdinter(gc, rr, &d1, hp, ro, rd);
166			if (d <= d0 \|\| d1 < -0.001)
167			continue; /* missed section */
168	gregl	3.5	if (checkdepth) { /* check depth */
169			if (hp->priv == &obstr && d0 < -0.001)
170			continue; /* ray starts too late */
171			if (hp->priv == &unobstr && d < 0.999*d1)
172			continue; /* ray ends too soon */
173			}
174			dc = hdcode(hp, d-d0);
175			bi = hdbindex(hp, gc); /* check for duplicates */
176			if (checkrepeats && (bp = hdgetbeam(hp, bi)) != NULL) {
177			for (n = bp->nrm, rv = hdbray(bp); n--; rv++)
178			if (rv->d == dc &&
179			rv->r[0][0] == rr[0][0] &&
180			rv->r[0][1] == rr[0][1] &&
181			rv->r[1][0] == rr[1][0] &&
182			rv->r[1][1] == rr[1][1])
183			break;
184			if (n >= 0)
185			continue; /* found a matching ray */
186			}
187			rv = hdnewrays(hp, bi, 1);
188			rv->d = dc;
189	gregl	3.1	rv->r[0][0] = rr[0][0]; rv->r[0][1] = rr[0][1];
190			rv->r[1][0] = rr[1][0]; rv->r[1][1] = rr[1][1];
191			copycolr(rv->v, cv);
192			}
193			}
194
195
196	gwlarson	3.10	addbeam(bp, hb) /* add a beam to our output holodeck */
197			register BEAM *bp;
198			register HDBEAMI *hb;
199	gregl	3.1	{
200			GCOORD gc[2];
201			FVECT ro, rd;
202			double d;
203			register int k;
204	gwlarson	3.10	/* get beam coordinates */
205			hdbcoord(gc, hb->h, hb->b);
206			/* add each ray to output */
207			for (k = bp->nrm; k--; ) {
208			d = hdray(ro, rd, hb->h, gc, hdbray(bp)[k].r);
209			if (hb->h->priv == &unobstr)
210			VSUM(ro, ro, rd, d);
211			else
212			d = 0.;
213			d = hddepth(hb->h, hdbray(bp)[k].d) - d;
214			addray(ro, rd, d, hdbray(bp)[k].v);
215			}
216			hdfreebeam(hb->h, hb->b); /* free the beam */
217			}
218
219
220			addholo(hdf) /* add a holodeck file */
221			char *hdf;
222			{
223			int fd;
224	gregl	3.4	/* open the holodeck for reading */
225			openholo(hdf, 0);
226	gregl	3.1	fd = hdlist[noutsects]->fd; /* remember the file handle */
227	gwlarson	3.10	while (hdlist[noutsects] != NULL) { /* load each section */
228			/* clump the beams */
229			clumpbeams(hdlist[noutsects], 0, BKBSIZE*1024, addbeam);
230			hddone(hdlist[noutsects]); /* free the section */
231	gregl	3.1	}
232	gwlarson	3.10	close(fd); /* close input file */
233	gregl	3.1	}
234
235
236			struct phead {
237			VIEW vw;
238			double expos;
239			short gotview;
240			short badfmt;
241			short altprims;
242			};
243
244
245	gwlarson	3.9	int
246	gregl	3.1	picheadline(s, ph) /* process picture header line */
247			char *s;
248			struct phead *ph;
249			{
250			char fmt[32];
251
252			if (formatval(fmt, s)) {
253			ph->badfmt = strcmp(fmt, COLRFMT);
254	gwlarson	3.9	return(0);
255	gregl	3.1	}
256			if (isprims(s)) {
257			ph->altprims++; /* don't want to deal with this */
258	gwlarson	3.9	return(0);
259	gregl	3.1	}
260			if (isexpos(s)) {
261			ph->expos *= exposval(s);
262	gwlarson	3.9	return(0);
263	gregl	3.1	}
264			if (isview(s)) {
265			ph->gotview += sscanview(&ph->vw, s);
266	gwlarson	3.9	return(0);
267	gregl	3.1	}
268	gwlarson	3.9	return(0);
269	gregl	3.1	}
270
271
272			addpicz(pcf, zbf) /* add a picture + depth-buffer */
273			char pcf, zbf;
274			{
275			FILE *pfp;
276			int zfd;
277			COLR *cscn;
278			float *zscn;
279			struct phead phd;
280			int eshft;
281			double emult;
282			RESOLU prs;
283			FLOAT vl[2];
284			FVECT ro, rd;
285			double aftd;
286			COLOR ctmp;
287			int j;
288			register int i;
289			/* open files */
290			if ((pfp = fopen(pcf, "r")) == NULL) {
291			sprintf(errmsg, "cannot open picture file \"%s\"", pcf);
292			error(SYSTEM, pcf);
293			}
294			if ((zfd = open(zbf, O_RDONLY)) < 0) {
295			sprintf(errmsg, "cannot open depth file \"%s\"", zbf);
296			error(SYSTEM, pcf);
297			}
298			/* load picture header */
299			copystruct(&phd.vw, &stdview);
300			phd.expos = 1.0;
301			phd.badfmt = phd.gotview = phd.altprims = 0;
302			if (getheader(pfp, picheadline, &phd) < 0 \|\|
303			phd.badfmt \|\| !fgetsresolu(&prs, pfp)) {
304			sprintf(errmsg, "bad format for picture file \"%s\"", pcf);
305			error(USER, errmsg);
306			}
307			if (!phd.gotview \|\| setview(&phd.vw) != NULL) {
308			sprintf(errmsg, "missing/illegal view in picture \"%s\"",
309			pcf);
310			error(USER, errmsg);
311			}
312			if (phd.altprims) {
313			sprintf(errmsg, "ignoring primary values in picture \"%s\"",
314			pcf);
315			error(WARNING, errmsg);
316			}
317			/* figure out what to do about exposure */
318			if (phd.expos < 0.99 \| phd.expos > 1.01) {
319			emult = -log(phd.expos)/log(2.);
320			eshft = emult >= 0. ? emult+.5 : emult-.5;
321			emult -= (double)eshft;
322			if (emult <= 0.01 & emult >= -0.01)
323			emult = -1.;
324			else {
325			emult = 1./phd.expos;
326			eshft = 0;
327			}
328			} else {
329			emult = -1.;
330			eshft = 0;
331			}
332			/* allocate buffers */
333			cscn = (COLR )malloc(scanlen(&prs)sizeof(COLR));
334			zscn = (float )malloc(scanlen(&prs)sizeof(float));
335			if (cscn == NULL \| zscn == NULL)
336			error(SYSTEM, "out of memory in addpicz");
337			/* read and process each scanline */
338			for (j = 0; j < numscans(&prs); j++) {
339			i = scanlen(&prs); /* read colrs */
340			if (freadcolrs(cscn, i, pfp) < 0) {
341			sprintf(errmsg, "error reading picture \"%s\"", pcf);
342			error(USER, errmsg);
343			}
344			if (eshft) /* shift exposure */
345			shiftcolrs(cscn, i, eshft);
346			i = sizeof(float); / read depth */
347			if (read(zfd, (char *)zscn, i) != i) {
348			sprintf(errmsg, "error reading depth file \"%s\"", zbf);
349			error(USER, errmsg);
350			}
351			for (i = scanlen(&prs); i--; ) { /* do each pixel */
352			pix2loc(vl, &prs, i, j);
353			aftd = viewray(ro, rd, &phd.vw, vl[0], vl[1]);
354			if (aftd < -FTINY)
355			continue; /* off view */
356			if (aftd > FTINY && zscn[i] > aftd)
357			continue; /* aft clipped */
358			if (emult > 0.) { /* whatta pain */
359			colr_color(ctmp, cscn[i]);
360			scalecolor(ctmp, emult);
361			setcolr(cscn[i], colval(ctmp,RED),
362			colval(ctmp,GRN), colval(ctmp,BLU));
363			}
364			addray(ro, rd, (double)zscn[i], cscn[i]);
365			}
366			}
367	gwlarson	3.10	/* write output */
368			hdsync(NULL, 1);
369	gregl	3.1	/* clean up */
370			free((char *)cscn);
371			free((char *)zscn);
372			fclose(pfp);
373			close(zfd);
374			}
375
376
377			eputs(s) /* put error message to stderr */
378			register char *s;
379			{
380			static int midline = 0;
381
382			if (!*s)
383			return;
384			if (!midline++) { /* prepend line with program name */
385			fputs(progname, stderr);
386			fputs(": ", stderr);
387			}
388			fputs(s, stderr);
389			if (s[strlen(s)-1] == '\n') {
390			fflush(stderr);
391			midline = 0;
392			}
393			}
394
395
396			quit(code) /* exit the program gracefully */
397			int code;
398			{
399			hdsync(NULL, 1); /* write out any buffered data */
400			exit(code);
401			}