src/px/pcomb.c

/* Copyright (c) 1992 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  "resolu.h"

#include "calcomp.h"

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

struct {
        char    *name;          /* file or command 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    Command[] = "<Command>";
char    vcolin[3][4] = {"ri", "gi", "bi"};
char    vcolout[3][4] = {"ro", "go", "bo"};
char    vbrtin[] = "li";
char    vbrtout[] = "lo";
char    vcolexp[3][4] = {"re", "ge", "be"};
char    vbrtexp[] = "le";

char    vnfiles[] = "nfiles";
char    vxmax[] = "xmax";
char    vymax[] = "ymax";
char    vxres[] = "xres";
char    vyres[] = "yres";
char    vxpos[] = "x";
char    vypos[] = "y";

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

int     xmax = 0, ymax = 0;             /* input resolution */

int     xscan, yscan;                   /* input position */

int     xres, yres;                     /* output resolution */

int     xpos, ypos;                     /* output position */

int     wrongformat = 0;

FILE    *popen();


main(argc, argv)
int     argc;
char    *argv[];
{
        int     original;
        double  f;
        int     a, i;
                                                /* scan options */
        for (a = 1; a < argc; a++) {
                if (argv[a][0] == '-')
                        switch (argv[a][1]) {
                        case 'x':
                        case 'y':
                                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;
        original = 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++;
                                continue;
                        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 {
                        if (argv[a][0] == '!') {
                                input[nfiles].name = Command;
                                input[nfiles].fp = popen(argv[a]+1, "r");
                        } else {
                                input[nfiles].name = argv[a];
                                input[nfiles].fp = fopen(argv[a], "r");
                        }
                        if (input[nfiles].fp == NULL) {
                                perror(argv[a]);
                                quit(1);
                        }
                }
                checkfile();
                if (original) {
                        colval(input[nfiles].coef,RED) /=
                                        colval(input[nfiles].expos,RED);
                        colval(input[nfiles].coef,GRN) /=
                                        colval(input[nfiles].expos,GRN);
                        colval(input[nfiles].coef,BLU) /=
                                        colval(input[nfiles].expos,BLU);
                }
                nfiles++;
                original = 0;
        }
        init();                         /* set constants */
                                        /* go back and get expressions */
        for (a = 1; a < argc; a++) {
                if (argv[a][0] == '-')
                        switch (argv[a][1]) {
                        case 'x':
                                varset(vxres, ':', eval(argv[++a]));
                                continue;
                        case 'y':
                                varset(vyres, ':', eval(argv[++a]));
                                continue;
                        case 'w':
                                continue;
                        case 'f':
                                fcompile(argv[++a]);
                                continue;
                        case 'e':
                                scompile(argv[++a], NULL, 0);
                                continue;
                        }
                break;
        }
                                                /* set/get output resolution */
        if (!vardefined(vxres))
                varset(vxres, ':', (double)xmax);
        if (!vardefined(vyres))
                varset(vyres, ':', (double)ymax);
        xres = varvalue(vxres) + .5;
        yres = varvalue(vyres) + .5;
        if (xres <= 0 || yres <= 0) {
                eputs(argv[0]);
                eputs(": illegal output resolution\n");
                quit(1);
        }
                                                /* complete header */
        printargs(argc, argv, stdout);
        fputformat(COLRFMT, stdout);
        putchar('\n');
        fprtresolu(xres, yres, stdout);
                                                /* combine pictures */
        combine();
        quit(0);
usage:
        eputs("Usage: ");
        eputs(argv[0]);
        eputs(
" [-w][-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);
        } else if (iscolcor(s)) {               /* color correction */
                colcorval(ctmp, s);
                multcolor(input[nfiles].expos, ctmp);
        }
                                                /* echo line */
        putchar('\t');
        fputs(s, stdout);
}


checkfile()                     /* ready a file */
{
        int     xinp, yinp;
        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(&xinp, &yinp, input[nfiles].fp) < 0) {
                eputs(input[nfiles].name);
                eputs(": bad picture size\n");
                quit(1);
        }
        if (xmax == 0 && ymax == 0) {
                xmax = xinp;
                ymax = yinp;
        } else if (xinp != xmax || yinp != ymax) {
                eputs(input[nfiles].name);
                eputs(": resolution mismatch\n");
                quit(1);
        }
                                        /* allocate scanlines */
        for (i = 0; i < WINSIZ; i++)
                input[nfiles].scan[i] = (COLOR *)emalloc(xmax*sizeof(COLOR));
}


init()                                  /* perform final setup */
{
        double  l_colin(), l_expos();
        register int    i;
                                                /* define constants */
        varset(vnfiles, ':', (double)nfiles);
        varset(vxmax, ':', (double)xmax);
        varset(vymax, ':', (double)ymax);
                                                /* 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));
                                                /* set input position */
        yscan = ymax+MIDSCN;
                                                /* combine files */
        for (ypos = yres-1; ypos >= 0; ypos--) {
            advance();
            varset(vypos, '=', (double)ypos);
            for (xpos = 0; xpos < xres; xpos++) {
                xscan = (long)xpos*xmax/xres;
                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][xscan],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 data for next scanline */
{
        extern double  fabs();
        int     ytarget;
        register COLOR  *st;
        register int    i, j;

        for (ytarget = (long)ypos*ymax/yres; yscan > ytarget; yscan--)
                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 (yscan <= MIDSCN)            /* hit bottom? */
                                continue;
                        if (freadscan(st, xmax, input[i].fp) < 0) {  /* read */
                                eputs(input[i].name);
                                eputs(": read error\n");
                                quit(1);
                        }
                        if (fabs(colval(input[i].coef,RED)-1.0) > 1e-3 ||
                                fabs(colval(input[i].coef,GRN)-1.0) > 1e-3 ||
                                fabs(colval(input[i].coef,BLU)-1.0) > 1e-3)
                                for (j = 0; j < xmax; j++)  /* adjust color */
                                        multcolor(st[j], input[i].coef);
                }
}


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

        fn = argument(1) - .5;
        if (fn < 0 || fn >= nfiles)
                return(1.0);
        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 (xscan+xoff < 0)
                                xoff = -xscan;
                } else {
                        xoff = d+.5;
                        if (xscan+xoff >= xmax)
                                xoff = xmax-1-xscan;
                }
        }
        if (n >= 3) {
                d = argument(3);
                if (d < 0.0) {
                        yoff = d-.5;
                        if (yoff+MIDSCN < 0)
                                yoff = -MIDSCN;
                        if (yscan+yoff < 0)
                                yoff = -yscan;
                } else {
                        yoff = d+.5;
                        if (yoff+MIDSCN >= WINSIZ)
                                yoff = WINSIZ-1-MIDSCN;
                        if (yscan+yoff >= ymax)
                                yoff = ymax-1-yscan;
                }
        }
        if (nam == vbrtin)
                return(bright(input[fn].scan[MIDSCN+yoff][xscan+xoff]));
        n = 3;
        while (n--)
            if (nam == vcolin[n])
                return(colval(input[fn].scan[MIDSCN+yoff][xscan+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)              /* exit gracefully */
int  code;
{
        register int  i;
                                /* close input files */
        for (i = 0; i < nfiles; i++)
                if (input[i].name == Command)
                        pclose(input[i].fp);
                else
                        fclose(input[i].fp);
        exit(code);
}
Revision:	2.6
Committed:	Tue Sep 8 10:35:05 1992 UTC (31 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.5:	+7 -20 lines
Log Message:	portability fixes
#	User	Rev	Content
1	greg	2.6	/* Copyright (c) 1992 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	greg	1.23	#include "resolu.h"
20
21	greg	1.1	#include "calcomp.h"
22
23	greg	1.6	#define MAXINP 32 /* maximum number of input files */
24	greg	1.14	#define WINSIZ 9 /* scanline window size */
25			#define MIDSCN 4 /* current scan position */
26	greg	1.1
27			struct {
28	greg	1.19	char name; / file or command name */
29	greg	1.1	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	greg	2.6	char Command[] = "<Command>";
38	greg	1.21	char vcolin[3][4] = {"ri", "gi", "bi"};
39			char vcolout[3][4] = {"ro", "go", "bo"};
40	greg	1.15	char vbrtin[] = "li";
41			char vbrtout[] = "lo";
42	greg	1.21	char vcolexp[3][4] = {"re", "ge", "be"};
43	greg	1.17	char vbrtexp[] = "le";
44	greg	1.1
45	greg	1.18	char vnfiles[] = "nfiles";
46			char vxmax[] = "xmax";
47			char vymax[] = "ymax";
48			char vxres[] = "xres";
49			char vyres[] = "yres";
50			char vxpos[] = "x";
51			char vypos[] = "y";
52	greg	1.1
53			int nowarn = 0; /* no warning messages? */
54
55	greg	1.18	int xmax = 0, ymax = 0; /* input resolution */
56	greg	1.9
57	greg	1.18	int xscan, yscan; /* input position */
58	greg	1.1
59	greg	1.18	int xres, yres; /* output resolution */
60	greg	1.1
61	greg	1.18	int xpos, ypos; /* output position */
62
63	greg	1.10	int wrongformat = 0;
64	greg	1.1
65	greg	1.19	FILE *popen();
66	greg	1.10
67	greg	1.19
68	greg	1.1	main(argc, argv)
69			int argc;
70			char *argv[];
71			{
72	greg	1.18	int original;
73	greg	1.3	double f;
74	greg	1.14	int a, i;
75	greg	1.15	/* scan options */
76			for (a = 1; a < argc; a++) {
77	greg	1.1	if (argv[a][0] == '-')
78			switch (argv[a][1]) {
79			case 'x':
80			case 'y':
81	greg	1.18	a++;
82	greg	1.15	continue;
83	greg	1.1	case 'w':
84			nowarn = !nowarn;
85	greg	1.15	continue;
86	greg	1.1	case 'f':
87			case 'e':
88	greg	1.16	a++;
89	greg	1.15	continue;
90	greg	1.1	}
91	greg	1.15	break;
92			}
93			/* process files */
94	greg	1.17	for (nfiles = 0; nfiles < MAXINP; nfiles++) {
95	greg	1.3	setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
96	greg	1.17	setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
97			}
98	greg	1.1	nfiles = 0;
99	greg	1.18	original = 0;
100	greg	1.1	for ( ; a < argc; a++) {
101			if (nfiles >= MAXINP) {
102			eputs(argv[0]);
103			eputs(": too many picture files\n");
104			quit(1);
105			}
106	greg	1.3	if (argv[a][0] == '-')
107			switch (argv[a][1]) {
108			case '\0':
109			input[nfiles].name = "<stdin>";
110			input[nfiles].fp = stdin;
111			break;
112	greg	1.17	case 'o':
113			original++;
114	greg	1.22	continue;
115	greg	1.3	case 's':
116			f = atof(argv[++a]);
117			scalecolor(input[nfiles].coef, f);
118			continue;
119			case 'c':
120			colval(input[nfiles].coef,RED)*=atof(argv[++a]);
121			colval(input[nfiles].coef,GRN)*=atof(argv[++a]);
122			colval(input[nfiles].coef,BLU)*=atof(argv[++a]);
123			continue;
124			default:
125			goto usage;
126			}
127			else {
128	greg	2.2	if (argv[a][0] == '!') {
129	greg	2.6	input[nfiles].name = Command;
130	greg	2.2	input[nfiles].fp = popen(argv[a]+1, "r");
131			} else {
132			input[nfiles].name = argv[a];
133			input[nfiles].fp = fopen(argv[a], "r");
134			}
135	greg	1.1	if (input[nfiles].fp == NULL) {
136	greg	1.6	perror(argv[a]);
137	greg	1.1	quit(1);
138			}
139			}
140	greg	1.16	checkfile();
141	greg	1.18	if (original) {
142			colval(input[nfiles].coef,RED) /=
143			colval(input[nfiles].expos,RED);
144			colval(input[nfiles].coef,GRN) /=
145			colval(input[nfiles].expos,GRN);
146			colval(input[nfiles].coef,BLU) /=
147			colval(input[nfiles].expos,BLU);
148			}
149			nfiles++;
150	greg	1.17	original = 0;
151	greg	1.15	}
152	greg	1.18	init(); /* set constants */
153	greg	1.15	/* go back and get expressions */
154			for (a = 1; a < argc; a++) {
155			if (argv[a][0] == '-')
156			switch (argv[a][1]) {
157			case 'x':
158	greg	1.21	varset(vxres, ':', eval(argv[++a]));
159	greg	1.18	continue;
160	greg	1.15	case 'y':
161	greg	1.21	varset(vyres, ':', eval(argv[++a]));
162	greg	1.16	continue;
163	greg	1.15	case 'w':
164			continue;
165			case 'f':
166			fcompile(argv[++a]);
167			continue;
168			case 'e':
169			scompile(argv[++a], NULL, 0);
170			continue;
171			}
172			break;
173			}
174	greg	1.18	/* set/get output resolution */
175			if (!vardefined(vxres))
176			varset(vxres, ':', (double)xmax);
177			if (!vardefined(vyres))
178			varset(vyres, ':', (double)ymax);
179			xres = varvalue(vxres) + .5;
180			yres = varvalue(vyres) + .5;
181			if (xres <= 0 \|\| yres <= 0) {
182			eputs(argv[0]);
183			eputs(": illegal output resolution\n");
184			quit(1);
185			}
186	greg	1.15	/* complete header */
187			printargs(argc, argv, stdout);
188			fputformat(COLRFMT, stdout);
189			putchar('\n');
190	greg	1.23	fprtresolu(xres, yres, stdout);
191	greg	1.15	/* combine pictures */
192			combine();
193			quit(0);
194			usage:
195			eputs("Usage: ");
196			eputs(argv[0]);
197			eputs(
198	greg	1.20	" [-w][-x xr][-y yr][-e expr][-f file] [ [-s f][-c r g b] pic ..]\n");
199	greg	1.15	quit(1);
200			}
201
202
203			tputs(s) /* put out string preceded by a tab */
204			char *s;
205			{
206			char fmt[32];
207			double d;
208			COLOR ctmp;
209
210			if (isformat(s)) { /* check format */
211			formatval(fmt, s);
212			wrongformat = strcmp(fmt, COLRFMT);
213	greg	1.17	return; /* don't echo */
214			}
215			if (isexpos(s)) { /* exposure */
216			d = exposval(s);
217			scalecolor(input[nfiles].expos, d);
218			} else if (iscolcor(s)) { /* color correction */
219	greg	1.15	colcorval(ctmp, s);
220	greg	1.17	multcolor(input[nfiles].expos, ctmp);
221	greg	1.15	}
222	greg	1.17	/* echo line */
223			putchar('\t');
224			fputs(s, stdout);
225	greg	1.16	}
226	greg	1.15
227	greg	1.16
228			checkfile() /* ready a file */
229			{
230	greg	1.18	int xinp, yinp;
231	greg	1.16	register int i;
232			/* process header */
233			fputs(input[nfiles].name, stdout);
234			fputs(":\n", stdout);
235			getheader(input[nfiles].fp, tputs, NULL);
236			if (wrongformat) {
237			eputs(input[nfiles].name);
238			eputs(": not in Radiance picture format\n");
239			quit(1);
240			}
241	greg	1.23	if (fgetresolu(&xinp, &yinp, input[nfiles].fp) < 0) {
242	greg	1.16	eputs(input[nfiles].name);
243			eputs(": bad picture size\n");
244			quit(1);
245			}
246	greg	1.18	if (xmax == 0 && ymax == 0) {
247			xmax = xinp;
248			ymax = yinp;
249			} else if (xinp != xmax \|\| yinp != ymax) {
250	greg	1.16	eputs(input[nfiles].name);
251			eputs(": resolution mismatch\n");
252			quit(1);
253			}
254			/* allocate scanlines */
255			for (i = 0; i < WINSIZ; i++)
256	greg	1.18	input[nfiles].scan[i] = (COLOR )emalloc(xmaxsizeof(COLOR));
257	greg	1.15	}
258
259
260	greg	1.18	init() /* perform final setup */
261	greg	1.15	{
262	greg	1.17	double l_colin(), l_expos();
263	greg	1.16	register int i;
264	greg	1.15	/* define constants */
265			varset(vnfiles, ':', (double)nfiles);
266	greg	1.18	varset(vxmax, ':', (double)xmax);
267			varset(vymax, ':', (double)ymax);
268	greg	1.15	/* set functions */
269			for (i = 0; i < 3; i++) {
270	greg	1.17	funset(vcolexp[i], 1, ':', l_expos);
271	greg	1.15	funset(vcolin[i], 1, '=', l_colin);
272			}
273	greg	1.17	funset(vbrtexp, 1, ':', l_expos);
274	greg	1.15	funset(vbrtin, 1, '=', l_colin);
275	greg	1.1	}
276
277
278			combine() /* combine pictures */
279			{
280	greg	1.8	EPNODE coldef[3], brtdef;
281	greg	1.1	COLOR *scanout;
282	greg	1.8	double d;
283	greg	1.1	register int i, j;
284			/* check defined variables */
285	greg	1.4	for (j = 0; j < 3; j++) {
286			if (vardefined(vcolout[j]))
287			coldef[j] = eparse(vcolout[j]);
288			else
289			coldef[j] = NULL;
290			}
291	greg	1.8	if (vardefined(vbrtout))
292			brtdef = eparse(vbrtout);
293			else
294			brtdef = NULL;
295	greg	1.1	/* allocate scanline */
296			scanout = (COLOR )emalloc(xressizeof(COLOR));
297	greg	1.18	/* set input position */
298			yscan = ymax+MIDSCN;
299	greg	1.1	/* combine files */
300			for (ypos = yres-1; ypos >= 0; ypos--) {
301	greg	1.14	advance();
302	greg	1.11	varset(vypos, '=', (double)ypos);
303	greg	1.8	for (xpos = 0; xpos < xres; xpos++) {
304	greg	1.18	xscan = (long)xpos*xmax/xres;
305	greg	1.11	varset(vxpos, '=', (double)xpos);
306	greg	1.8	eclock++;
307			if (brtdef != NULL) {
308			d = evalue(brtdef);
309			if (d < 0.0)
310			d = 0.0;
311			setcolor(scanout[xpos], d, d, d);
312			} else {
313			for (j = 0; j < 3; j++) {
314			if (coldef[j] != NULL) {
315	greg	1.13	d = evalue(coldef[j]);
316	greg	1.8	} else {
317	greg	1.13	d = 0.0;
318	greg	1.8	for (i = 0; i < nfiles; i++)
319	greg	1.18	d += colval(input[i].scan[MIDSCN][xscan],j);
320	greg	1.1	}
321	greg	1.13	if (d < 0.0)
322			d = 0.0;
323			colval(scanout[xpos],j) = d;
324	greg	1.8	}
325	greg	1.1	}
326	greg	1.8	}
327			if (fwritescan(scanout, xres, stdout) < 0) {
328			perror("write error");
329			quit(1);
330			}
331	greg	1.1	}
332			efree(scanout);
333			}
334
335
336	greg	1.18	advance() /* read in data for next scanline */
337	greg	1.14	{
338	greg	2.4	extern double fabs();
339	greg	1.18	int ytarget;
340	greg	1.14	register COLOR *st;
341			register int i, j;
342
343	greg	1.18	for (ytarget = (long)ypos*ymax/yres; yscan > ytarget; yscan--)
344			for (i = 0; i < nfiles; i++) {
345			st = input[i].scan[WINSIZ-1];
346			for (j = WINSIZ-1; j > 0; j--) /* rotate window */
347			input[i].scan[j] = input[i].scan[j-1];
348			input[i].scan[0] = st;
349			if (yscan <= MIDSCN) /* hit bottom? */
350			continue;
351	greg	2.4	if (freadscan(st, xmax, input[i].fp) < 0) { /* read */
352	greg	1.18	eputs(input[i].name);
353			eputs(": read error\n");
354			quit(1);
355			}
356	greg	2.4	if (fabs(colval(input[i].coef,RED)-1.0) > 1e-3 \|\|
357			fabs(colval(input[i].coef,GRN)-1.0) > 1e-3 \|\|
358			fabs(colval(input[i].coef,BLU)-1.0) > 1e-3)
359			for (j = 0; j < xmax; j++) /* adjust color */
360			multcolor(st[j], input[i].coef);
361	greg	1.14	}
362			}
363
364
365	greg	1.1	double
366	greg	1.17	l_expos(nam) /* return picture exposure */
367	greg	1.15	register char *nam;
368	greg	1.1	{
369	greg	1.15	register int fn, n;
370	greg	1.14
371	greg	1.18	fn = argument(1) - .5;
372			if (fn < 0 \|\| fn >= nfiles)
373			return(1.0);
374	greg	1.17	if (nam == vbrtexp)
375			return(bright(input[fn].expos));
376	greg	1.15	n = 3;
377			while (n--)
378	greg	1.17	if (nam == vcolexp[n])
379			return(colval(input[fn].expos,n));
380			eputs("Bad call to l_expos()!\n");
381	greg	1.15	quit(1);
382			}
383
384
385			double
386			l_colin(nam) /* return color value for picture */
387			register char *nam;
388			{
389			int fn;
390			register int n, xoff, yoff;
391			double d;
392
393	greg	1.16	d = argument(1);
394			if (d > -.5 && d < .5)
395			return((double)nfiles);
396			fn = d - .5;
397			if (fn < 0 \|\| fn >= nfiles) {
398	greg	1.15	errno = EDOM;
399			return(0.0);
400			}
401	greg	1.14	xoff = yoff = 0;
402			n = nargum();
403			if (n >= 2) {
404			d = argument(2);
405			if (d < 0.0) {
406			xoff = d-.5;
407	greg	1.18	if (xscan+xoff < 0)
408			xoff = -xscan;
409	greg	1.14	} else {
410			xoff = d+.5;
411	greg	1.18	if (xscan+xoff >= xmax)
412			xoff = xmax-1-xscan;
413	greg	1.14	}
414			}
415			if (n >= 3) {
416			d = argument(3);
417			if (d < 0.0) {
418			yoff = d-.5;
419			if (yoff+MIDSCN < 0)
420			yoff = -MIDSCN;
421	greg	1.18	if (yscan+yoff < 0)
422			yoff = -yscan;
423	greg	1.14	} else {
424			yoff = d+.5;
425			if (yoff+MIDSCN >= WINSIZ)
426			yoff = WINSIZ-1-MIDSCN;
427	greg	1.18	if (yscan+yoff >= ymax)
428			yoff = ymax-1-yscan;
429	greg	1.14	}
430			}
431	greg	1.15	if (nam == vbrtin)
432	greg	1.18	return(bright(input[fn].scan[MIDSCN+yoff][xscan+xoff]));
433	greg	1.15	n = 3;
434			while (n--)
435			if (nam == vcolin[n])
436	greg	1.18	return(colval(input[fn].scan[MIDSCN+yoff][xscan+xoff],n));
437	greg	1.15	eputs("Bad call to l_colin()!\n");
438			quit(1);
439	greg	1.1	}
440
441
442			wputs(msg)
443			char *msg;
444			{
445			if (!nowarn)
446			eputs(msg);
447			}
448
449
450			eputs(msg)
451			char *msg;
452			{
453			fputs(msg, stderr);
454			}
455
456
457	greg	2.4	quit(code) /* exit gracefully */
458			int code;
459			{
460	greg	2.5	register int i;
461			/* close input files */
462			for (i = 0; i < nfiles; i++)
463	greg	2.6	if (input[i].name == Command)
464			pclose(input[i].fp);
465			else
466			fclose(input[i].fp);
467	greg	1.1	exit(code);
468			}