src/px/pcomb.c

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

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

/*
 *  Combine picture files according to calcomp functions.
 *
 *      1/4/89
 */

#include <stdio.h>

#include <errno.h>

#include "color.h"

#include "calcomp.h"

#define MAXINP          32              /* maximum number of input files */
#define WINSIZ          9               /* scanline window size */
#define MIDSCN          4               /* current scan position */

#define BRT             (-1)            /* special index for brightness */

struct {
        char    *name;          /* file name */
        FILE    *fp;            /* stream pointer */
        COLOR   *scan[WINSIZ];  /* input scanline window */
        COLOR   coef;           /* coefficient */
        COLOR   expos;          /* recorded exposure */
}       input[MAXINP];                  /* input pictures */

int     nfiles;                         /* number of input files */

char    *vcolin[3] = {"ri", "gi", "bi"};
char    *vcolout[3] = {"ro", "go", "bo"};
char    vbrtin[] = "li";
char    vbrtout[] = "lo";
char    *vcolexp[3] = {"re", "ge", "be"};
char    vbrtexp[] = "le";

#define vnfiles         "nfiles"
#define vxres           "xres"
#define vyres           "yres"
#define vxpos           "x"
#define vypos           "y"

int     nowarn = 0;                     /* no warning messages? */

int     original = 0;                   /* origninal values? */

int     xres=0, yres=0;                 /* picture resolution */

int     xpos, ypos;                     /* picture position */

int     wrongformat = 0;


main(argc, argv)
int     argc;
char    *argv[];
{
        double  f;
        int     a, i;
                                                /* scan options */
        for (a = 1; a < argc; a++) {
                if (argv[a][0] == '-')
                        switch (argv[a][1]) {
                        case 'x':
                                xres = atoi(argv[++a]);
                                continue;
                        case 'y':
                                yres = atoi(argv[++a]);
                                continue;
                        case 'w':
                                nowarn = !nowarn;
                                continue;
                        case 'f':
                        case 'e':
                                a++;
                                continue;
                        }
                break;
        }
                                        /* process files */
        for (nfiles = 0; nfiles < MAXINP; nfiles++) {
                setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
                setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
        }
        nfiles = 0;
        for ( ; a < argc; a++) {
                if (nfiles >= MAXINP) {
                        eputs(argv[0]);
                        eputs(": too many picture files\n");
                        quit(1);
                }
                if (argv[a][0] == '-')
                        switch (argv[a][1]) {
                        case '\0':
                                input[nfiles].name = "<stdin>";
                                input[nfiles].fp = stdin;
                                break;
                        case 'o':
                                original++;
                                break;
                        case 's':
                                f = atof(argv[++a]);
                                scalecolor(input[nfiles].coef, f);
                                continue;
                        case 'c':
                                colval(input[nfiles].coef,RED)*=atof(argv[++a]);
                                colval(input[nfiles].coef,GRN)*=atof(argv[++a]);
                                colval(input[nfiles].coef,BLU)*=atof(argv[++a]);
                                continue;
                        default:
                                goto usage;
                        }
                else {
                        input[nfiles].name = argv[a];
                        input[nfiles].fp = fopen(argv[a], "r");
                        if (input[nfiles].fp == NULL) {
                                perror(argv[a]);
                                quit(1);
                        }
                }
                checkfile();
                original = 0;
                nfiles++;
        }
        init();                         /* set constant expressions */
                                        /* go back and get expressions */
        for (a = 1; a < argc; a++) {
                if (argv[a][0] == '-')
                        switch (argv[a][1]) {
                        case 'x':
                        case 'y':
                                a++;
                                continue;
                        case 'w':
                                continue;
                        case 'f':
                                fcompile(argv[++a]);
                                continue;
                        case 'e':
                                scompile(argv[++a], NULL, 0);
                                continue;
                        }
                break;
        }
                                                /* complete header */
        printargs(argc, argv, stdout);
        fputformat(COLRFMT, stdout);
        putchar('\n');
        fputresolu(YMAJOR|YDECR, xres, yres, stdout);
                                                /* combine pictures */
        combine();
        quit(0);
usage:
        eputs("Usage: ");
        eputs(argv[0]);
        eputs(
" [-w][-h][-x xr][-y yr][-e expr][-f file] [ [-s f][-c r g b] pic ..]\n");
        quit(1);
}


tputs(s)                        /* put out string preceded by a tab */
char    *s;
{
        char    fmt[32];
        double  d;
        COLOR   ctmp;

        if (isformat(s)) {                      /* check format */
                formatval(fmt, s);
                wrongformat = strcmp(fmt, COLRFMT);
                return;         /* don't echo */
        }
        if (isexpos(s)) {                       /* exposure */
                d = exposval(s);
                scalecolor(input[nfiles].expos, d);
                if (original)
                        scalecolor(input[nfiles].coef, 1.0/d);
        } else if (iscolcor(s)) {               /* color correction */
                colcorval(ctmp, s);
                multcolor(input[nfiles].expos, ctmp);
                if (original) {
                        colval(input[nfiles].coef,RED) /= colval(ctmp,RED);
                        colval(input[nfiles].coef,GRN) /= colval(ctmp,GRN);
                        colval(input[nfiles].coef,BLU) /= colval(ctmp,BLU);
                }
        }
                                                /* echo line */
        putchar('\t');
        fputs(s, stdout);
}


checkfile()                     /* ready a file */
{
        register int    i;
                                        /* process header */
        fputs(input[nfiles].name, stdout);
        fputs(":\n", stdout);
        getheader(input[nfiles].fp, tputs, NULL);
        if (wrongformat) {
                eputs(input[nfiles].name);
                eputs(": not in Radiance picture format\n");
                quit(1);
        }
        if (fgetresolu(&xpos, &ypos, input[nfiles].fp) != (YMAJOR|YDECR)) {
                eputs(input[nfiles].name);
                eputs(": bad picture size\n");
                quit(1);
        }
        if (xres == 0 && yres == 0) {
                xres = xpos;
                yres = ypos;
        } else if (xpos != xres || ypos != yres) {
                eputs(input[nfiles].name);
                eputs(": resolution mismatch\n");
                quit(1);
        }
                                        /* allocate scanlines */
        for (i = 0; i < WINSIZ; i++)
                input[nfiles].scan[i] = (COLOR *)emalloc(xres*sizeof(COLOR));
}


init()                          /* perform final setup */
{
        double  l_colin(), l_expos();
        register int    i;
                                                /* prime input */
        for (ypos = yres+(MIDSCN-1); ypos >= yres; ypos--)
                advance();
                                                /* define constants */
        varset(vnfiles, ':', (double)nfiles);
        varset(vxres, ':', (double)xres);
        varset(vyres, ':', (double)yres);
                                                /* set functions */
        for (i = 0; i < 3; i++) {
                funset(vcolexp[i], 1, ':', l_expos);
                funset(vcolin[i], 1, '=', l_colin);
        }
        funset(vbrtexp, 1, ':', l_expos);
        funset(vbrtin, 1, '=', l_colin);
}


combine()                       /* combine pictures */
{
        EPNODE  *coldef[3], *brtdef;
        COLOR   *scanout;
        double  d;
        register int    i, j;
                                                /* check defined variables */
        for (j = 0; j < 3; j++) {
                if (vardefined(vcolout[j]))
                        coldef[j] = eparse(vcolout[j]);
                else
                        coldef[j] = NULL;
        }
        if (vardefined(vbrtout))
                brtdef = eparse(vbrtout);
        else
                brtdef = NULL;
                                                /* allocate scanline */
        scanout = (COLOR *)emalloc(xres*sizeof(COLOR));
                                                /* combine files */
        for (ypos = yres-1; ypos >= 0; ypos--) {
            advance();
            varset(vypos, '=', (double)ypos);
            for (xpos = 0; xpos < xres; xpos++) {
                varset(vxpos, '=', (double)xpos);
                eclock++;
                if (brtdef != NULL) {
                    d = evalue(brtdef);
                    if (d < 0.0)
                        d = 0.0;
                    setcolor(scanout[xpos], d, d, d);
                } else {
                    for (j = 0; j < 3; j++) {
                        if (coldef[j] != NULL) {
                                d = evalue(coldef[j]);
                        } else {
                            d = 0.0;
                            for (i = 0; i < nfiles; i++)
                                d += colval(input[i].scan[MIDSCN][xpos],j);
                        }
                        if (d < 0.0)
                            d = 0.0;
                        colval(scanout[xpos],j) = d;
                    }
                }
            }
            if (fwritescan(scanout, xres, stdout) < 0) {
                    perror("write error");
                    quit(1);
            }
        }
        efree(scanout);
}


advance()                       /* read in next scanline */
{
        register COLOR  *st;
        register int    i, j;

        for (i = 0; i < nfiles; i++) {
                st = input[i].scan[WINSIZ-1];
                for (j = WINSIZ-1; j > 0; j--)  /* rotate window */
                        input[i].scan[j] = input[i].scan[j-1];
                input[i].scan[0] = st;
                if (ypos < MIDSCN)              /* hit bottom */
                        continue;
                if (freadscan(st, xres, input[i].fp) < 0) {
                        eputs(input[i].name);
                        eputs(": read error\n");
                        quit(1);
                }
                for (j = 0; j < xres; j++)      /* adjust color */
                        multcolor(st[j], input[i].coef);
        }
}


double
l_expos(nam)                    /* return picture exposure */
register char   *nam;
{
        register int    fn, n;
        double  d;

        d = argument(1);
        if (d > -.5 && d < .5)
                return((double)nfiles);
        fn = d - .5;
        if (fn < 0 || fn >= nfiles) {
                errno = EDOM;
                return(0.0);
        }
        if (nam == vbrtexp)
                return(bright(input[fn].expos));
        n = 3;
        while (n--)
                if (nam == vcolexp[n])
                        return(colval(input[fn].expos,n));
        eputs("Bad call to l_expos()!\n");
        quit(1);
}


double
l_colin(nam)                    /* return color value for picture */
register char   *nam;
{
        int     fn;
        register int    n, xoff, yoff;
        double  d;

        d = argument(1);
        if (d > -.5 && d < .5)
                return((double)nfiles);
        fn = d - .5;
        if (fn < 0 || fn >= nfiles) {
                errno = EDOM;
                return(0.0);
        }
        xoff = yoff = 0;
        n = nargum();
        if (n >= 2) {
                d = argument(2);
                if (d < 0.0) {
                        xoff = d-.5;
                        if (xpos+xoff < 0)
                                xoff = -xpos;
                } else {
                        xoff = d+.5;
                        if (xpos+xoff >= xres)
                                xoff = xres-1-xpos;
                }
        }
        if (n >= 3) {
                d = argument(3);
                if (d < 0.0) {
                        yoff = d-.5;
                        if (yoff+MIDSCN < 0)
                                yoff = -MIDSCN;
                        if (ypos+yoff < 0)
                                yoff = -ypos;
                } else {
                        yoff = d+.5;
                        if (yoff+MIDSCN >= WINSIZ)
                                yoff = WINSIZ-1-MIDSCN;
                        if (ypos+yoff >= yres)
                                yoff = yres-1-ypos;
                }
        }
        if (nam == vbrtin)
                return(bright(input[fn].scan[MIDSCN+yoff][xpos+xoff]));
        n = 3;
        while (n--)
            if (nam == vcolin[n])
                return(colval(input[fn].scan[MIDSCN+yoff][xpos+xoff],n));
        eputs("Bad call to l_colin()!\n");
        quit(1);
}


wputs(msg)
char    *msg;
{
        if (!nowarn)
                eputs(msg);
}


eputs(msg)
char    *msg;
{
        fputs(msg, stderr);
}


quit(code)
int     code;
{
        exit(code);
}
Revision:	1.17
Committed:	Fri May 24 17:14:49 1991 UTC (32 years, 11 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.16:	+36 -26 lines
Log Message:	changed operation of -o option
#	User	Rev	Content
1	greg	1.8	/* 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			* Combine picture files according to calcomp functions.
9			*
10			* 1/4/89
11			*/
12
13			#include <stdio.h>
14
15			#include <errno.h>
16
17			#include "color.h"
18
19			#include "calcomp.h"
20
21	greg	1.6	#define MAXINP 32 /* maximum number of input files */
22	greg	1.14	#define WINSIZ 9 /* scanline window size */
23			#define MIDSCN 4 /* current scan position */
24	greg	1.1
25	greg	1.14	#define BRT (-1) /* special index for brightness */
26
27	greg	1.1	struct {
28			char name; / file name */
29			FILE fp; / stream pointer */
30	greg	1.14	COLOR scan[WINSIZ]; / input scanline window */
31	greg	1.3	COLOR coef; /* coefficient */
32	greg	1.17	COLOR expos; /* recorded exposure */
33	greg	1.1	} input[MAXINP]; /* input pictures */
34
35			int nfiles; /* number of input files */
36
37			char *vcolin[3] = {"ri", "gi", "bi"};
38			char *vcolout[3] = {"ro", "go", "bo"};
39	greg	1.15	char vbrtin[] = "li";
40			char vbrtout[] = "lo";
41	greg	1.17	char *vcolexp[3] = {"re", "ge", "be"};
42			char vbrtexp[] = "le";
43	greg	1.1
44	greg	1.8	#define vnfiles "nfiles"
45			#define vxres "xres"
46			#define vyres "yres"
47	greg	1.1	#define vxpos "x"
48			#define vypos "y"
49
50			int nowarn = 0; /* no warning messages? */
51
52	greg	1.9	int original = 0; /* origninal values? */
53
54	greg	1.1	int xres=0, yres=0; /* picture resolution */
55
56			int xpos, ypos; /* picture position */
57
58	greg	1.10	int wrongformat = 0;
59	greg	1.1
60	greg	1.10
61	greg	1.1	main(argc, argv)
62			int argc;
63			char *argv[];
64			{
65	greg	1.3	double f;
66	greg	1.14	int a, i;
67	greg	1.15	/* scan options */
68			for (a = 1; a < argc; a++) {
69	greg	1.1	if (argv[a][0] == '-')
70			switch (argv[a][1]) {
71			case 'x':
72			xres = atoi(argv[++a]);
73	greg	1.15	continue;
74	greg	1.1	case 'y':
75			yres = atoi(argv[++a]);
76	greg	1.15	continue;
77	greg	1.1	case 'w':
78			nowarn = !nowarn;
79	greg	1.15	continue;
80	greg	1.1	case 'f':
81			case 'e':
82	greg	1.16	a++;
83	greg	1.15	continue;
84	greg	1.1	}
85	greg	1.15	break;
86			}
87			/* process files */
88	greg	1.17	for (nfiles = 0; nfiles < MAXINP; nfiles++) {
89	greg	1.3	setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
90	greg	1.17	setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
91			}
92	greg	1.1	nfiles = 0;
93			for ( ; a < argc; a++) {
94			if (nfiles >= MAXINP) {
95			eputs(argv[0]);
96			eputs(": too many picture files\n");
97			quit(1);
98			}
99	greg	1.3	if (argv[a][0] == '-')
100			switch (argv[a][1]) {
101			case '\0':
102			input[nfiles].name = "<stdin>";
103			input[nfiles].fp = stdin;
104			break;
105	greg	1.17	case 'o':
106			original++;
107			break;
108	greg	1.3	case 's':
109			f = atof(argv[++a]);
110			scalecolor(input[nfiles].coef, f);
111			continue;
112			case 'c':
113			colval(input[nfiles].coef,RED)*=atof(argv[++a]);
114			colval(input[nfiles].coef,GRN)*=atof(argv[++a]);
115			colval(input[nfiles].coef,BLU)*=atof(argv[++a]);
116			continue;
117			default:
118			goto usage;
119			}
120			else {
121	greg	1.1	input[nfiles].name = argv[a];
122			input[nfiles].fp = fopen(argv[a], "r");
123			if (input[nfiles].fp == NULL) {
124	greg	1.6	perror(argv[a]);
125	greg	1.1	quit(1);
126			}
127			}
128	greg	1.16	checkfile();
129	greg	1.17	original = 0;
130	greg	1.15	nfiles++;
131			}
132	greg	1.16	init(); /* set constant expressions */
133	greg	1.15	/* go back and get expressions */
134			for (a = 1; a < argc; a++) {
135			if (argv[a][0] == '-')
136			switch (argv[a][1]) {
137			case 'x':
138			case 'y':
139	greg	1.16	a++;
140			continue;
141	greg	1.15	case 'w':
142			continue;
143			case 'f':
144			fcompile(argv[++a]);
145			continue;
146			case 'e':
147			scompile(argv[++a], NULL, 0);
148			continue;
149			}
150			break;
151			}
152			/* complete header */
153			printargs(argc, argv, stdout);
154			fputformat(COLRFMT, stdout);
155			putchar('\n');
156			fputresolu(YMAJOR\|YDECR, xres, yres, stdout);
157			/* combine pictures */
158			combine();
159			quit(0);
160			usage:
161			eputs("Usage: ");
162			eputs(argv[0]);
163			eputs(
164			" [-w][-h][-x xr][-y yr][-e expr][-f file] [ [-s f][-c r g b] pic ..]\n");
165			quit(1);
166			}
167
168
169			tputs(s) /* put out string preceded by a tab */
170			char *s;
171			{
172			char fmt[32];
173			double d;
174			COLOR ctmp;
175
176			if (isformat(s)) { /* check format */
177			formatval(fmt, s);
178			wrongformat = strcmp(fmt, COLRFMT);
179	greg	1.17	return; /* don't echo */
180			}
181			if (isexpos(s)) { /* exposure */
182			d = exposval(s);
183			scalecolor(input[nfiles].expos, d);
184			if (original)
185			scalecolor(input[nfiles].coef, 1.0/d);
186			} else if (iscolcor(s)) { /* color correction */
187	greg	1.15	colcorval(ctmp, s);
188	greg	1.17	multcolor(input[nfiles].expos, ctmp);
189			if (original) {
190			colval(input[nfiles].coef,RED) /= colval(ctmp,RED);
191			colval(input[nfiles].coef,GRN) /= colval(ctmp,GRN);
192			colval(input[nfiles].coef,BLU) /= colval(ctmp,BLU);
193			}
194	greg	1.15	}
195	greg	1.17	/* echo line */
196			putchar('\t');
197			fputs(s, stdout);
198	greg	1.16	}
199	greg	1.15
200	greg	1.16
201			checkfile() /* ready a file */
202			{
203			register int i;
204			/* process header */
205			fputs(input[nfiles].name, stdout);
206			fputs(":\n", stdout);
207			getheader(input[nfiles].fp, tputs, NULL);
208			if (wrongformat) {
209			eputs(input[nfiles].name);
210			eputs(": not in Radiance picture format\n");
211			quit(1);
212			}
213			if (fgetresolu(&xpos, &ypos, input[nfiles].fp) != (YMAJOR\|YDECR)) {
214			eputs(input[nfiles].name);
215			eputs(": bad picture size\n");
216			quit(1);
217			}
218			if (xres == 0 && yres == 0) {
219			xres = xpos;
220			yres = ypos;
221			} else if (xpos != xres \|\| ypos != yres) {
222			eputs(input[nfiles].name);
223			eputs(": resolution mismatch\n");
224			quit(1);
225			}
226			/* allocate scanlines */
227			for (i = 0; i < WINSIZ; i++)
228			input[nfiles].scan[i] = (COLOR )emalloc(xressizeof(COLOR));
229	greg	1.15	}
230
231
232	greg	1.16	init() /* perform final setup */
233	greg	1.15	{
234	greg	1.17	double l_colin(), l_expos();
235	greg	1.16	register int i;
236	greg	1.15	/* prime input */
237			for (ypos = yres+(MIDSCN-1); ypos >= yres; ypos--)
238			advance();
239			/* define constants */
240			varset(vnfiles, ':', (double)nfiles);
241			varset(vxres, ':', (double)xres);
242			varset(vyres, ':', (double)yres);
243			/* set functions */
244			for (i = 0; i < 3; i++) {
245	greg	1.17	funset(vcolexp[i], 1, ':', l_expos);
246	greg	1.15	funset(vcolin[i], 1, '=', l_colin);
247			}
248	greg	1.17	funset(vbrtexp, 1, ':', l_expos);
249	greg	1.15	funset(vbrtin, 1, '=', l_colin);
250	greg	1.1	}
251
252
253			combine() /* combine pictures */
254			{
255	greg	1.8	EPNODE coldef[3], brtdef;
256	greg	1.1	COLOR *scanout;
257	greg	1.8	double d;
258	greg	1.1	register int i, j;
259			/* check defined variables */
260	greg	1.4	for (j = 0; j < 3; j++) {
261			if (vardefined(vcolout[j]))
262			coldef[j] = eparse(vcolout[j]);
263			else
264			coldef[j] = NULL;
265			}
266	greg	1.8	if (vardefined(vbrtout))
267			brtdef = eparse(vbrtout);
268			else
269			brtdef = NULL;
270	greg	1.1	/* allocate scanline */
271			scanout = (COLOR )emalloc(xressizeof(COLOR));
272			/* combine files */
273			for (ypos = yres-1; ypos >= 0; ypos--) {
274	greg	1.14	advance();
275	greg	1.11	varset(vypos, '=', (double)ypos);
276	greg	1.8	for (xpos = 0; xpos < xres; xpos++) {
277	greg	1.11	varset(vxpos, '=', (double)xpos);
278	greg	1.8	eclock++;
279			if (brtdef != NULL) {
280			d = evalue(brtdef);
281			if (d < 0.0)
282			d = 0.0;
283			setcolor(scanout[xpos], d, d, d);
284			} else {
285			for (j = 0; j < 3; j++) {
286			if (coldef[j] != NULL) {
287	greg	1.13	d = evalue(coldef[j]);
288	greg	1.8	} else {
289	greg	1.13	d = 0.0;
290	greg	1.8	for (i = 0; i < nfiles; i++)
291	greg	1.14	d += colval(input[i].scan[MIDSCN][xpos],j);
292	greg	1.1	}
293	greg	1.13	if (d < 0.0)
294			d = 0.0;
295			colval(scanout[xpos],j) = d;
296	greg	1.8	}
297	greg	1.1	}
298	greg	1.8	}
299			if (fwritescan(scanout, xres, stdout) < 0) {
300			perror("write error");
301			quit(1);
302			}
303	greg	1.1	}
304			efree(scanout);
305			}
306
307
308	greg	1.14	advance() /* read in next scanline */
309			{
310			register COLOR *st;
311			register int i, j;
312
313			for (i = 0; i < nfiles; i++) {
314			st = input[i].scan[WINSIZ-1];
315			for (j = WINSIZ-1; j > 0; j--) /* rotate window */
316			input[i].scan[j] = input[i].scan[j-1];
317			input[i].scan[0] = st;
318			if (ypos < MIDSCN) /* hit bottom */
319			continue;
320			if (freadscan(st, xres, input[i].fp) < 0) {
321			eputs(input[i].name);
322			eputs(": read error\n");
323			quit(1);
324			}
325			for (j = 0; j < xres; j++) /* adjust color */
326			multcolor(st[j], input[i].coef);
327			}
328			}
329
330
331	greg	1.1	double
332	greg	1.17	l_expos(nam) /* return picture exposure */
333	greg	1.15	register char *nam;
334	greg	1.1	{
335	greg	1.15	register int fn, n;
336	greg	1.14	double d;
337
338	greg	1.16	d = argument(1);
339			if (d > -.5 && d < .5)
340			return((double)nfiles);
341			fn = d - .5;
342			if (fn < 0 \|\| fn >= nfiles) {
343	greg	1.1	errno = EDOM;
344			return(0.0);
345			}
346	greg	1.17	if (nam == vbrtexp)
347			return(bright(input[fn].expos));
348	greg	1.15	n = 3;
349			while (n--)
350	greg	1.17	if (nam == vcolexp[n])
351			return(colval(input[fn].expos,n));
352			eputs("Bad call to l_expos()!\n");
353	greg	1.15	quit(1);
354			}
355
356
357			double
358			l_colin(nam) /* return color value for picture */
359			register char *nam;
360			{
361			int fn;
362			register int n, xoff, yoff;
363			double d;
364
365	greg	1.16	d = argument(1);
366			if (d > -.5 && d < .5)
367			return((double)nfiles);
368			fn = d - .5;
369			if (fn < 0 \|\| fn >= nfiles) {
370	greg	1.15	errno = EDOM;
371			return(0.0);
372			}
373	greg	1.14	xoff = yoff = 0;
374			n = nargum();
375			if (n >= 2) {
376			d = argument(2);
377			if (d < 0.0) {
378			xoff = d-.5;
379			if (xpos+xoff < 0)
380			xoff = -xpos;
381			} else {
382			xoff = d+.5;
383			if (xpos+xoff >= xres)
384			xoff = xres-1-xpos;
385			}
386			}
387			if (n >= 3) {
388			d = argument(3);
389			if (d < 0.0) {
390			yoff = d-.5;
391			if (yoff+MIDSCN < 0)
392			yoff = -MIDSCN;
393			if (ypos+yoff < 0)
394			yoff = -ypos;
395			} else {
396			yoff = d+.5;
397			if (yoff+MIDSCN >= WINSIZ)
398			yoff = WINSIZ-1-MIDSCN;
399			if (ypos+yoff >= yres)
400			yoff = yres-1-ypos;
401			}
402			}
403	greg	1.15	if (nam == vbrtin)
404	greg	1.14	return(bright(input[fn].scan[MIDSCN+yoff][xpos+xoff]));
405	greg	1.15	n = 3;
406			while (n--)
407			if (nam == vcolin[n])
408			return(colval(input[fn].scan[MIDSCN+yoff][xpos+xoff],n));
409			eputs("Bad call to l_colin()!\n");
410			quit(1);
411	greg	1.1	}
412
413
414			wputs(msg)
415			char *msg;
416			{
417			if (!nowarn)
418			eputs(msg);
419			}
420
421
422			eputs(msg)
423			char *msg;
424			{
425			fputs(msg, stderr);
426			}
427
428
429			quit(code)
430			int code;
431			{
432			exit(code);
433			}