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 */

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    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++;
                                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 = argv[a][0]=='!' ?
                                        popen(argv[a]+1, "r") :
                                        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');
        fputresolu(YMAJOR|YDECR, 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) != (YMAJOR|YDECR)) {
                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 */
{
        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);
                        }
                        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)
int     code;
{
        exit(code);
}
Revision:	1.21
Committed:	Wed Aug 14 15:00:34 1991 UTC (34 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.20:	+5 -14 lines
Log Message:	inconsequential changes
#	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			struct {
26	greg	1.19	char name; / file or command name */
27	greg	1.1	FILE fp; / stream pointer */
28	greg	1.14	COLOR scan[WINSIZ]; / input scanline window */
29	greg	1.3	COLOR coef; /* coefficient */
30	greg	1.17	COLOR expos; /* recorded exposure */
31	greg	1.1	} input[MAXINP]; /* input pictures */
32
33			int nfiles; /* number of input files */
34
35	greg	1.21	char vcolin[3][4] = {"ri", "gi", "bi"};
36			char vcolout[3][4] = {"ro", "go", "bo"};
37	greg	1.15	char vbrtin[] = "li";
38			char vbrtout[] = "lo";
39	greg	1.21	char vcolexp[3][4] = {"re", "ge", "be"};
40	greg	1.17	char vbrtexp[] = "le";
41	greg	1.1
42	greg	1.18	char vnfiles[] = "nfiles";
43			char vxmax[] = "xmax";
44			char vymax[] = "ymax";
45			char vxres[] = "xres";
46			char vyres[] = "yres";
47			char vxpos[] = "x";
48			char vypos[] = "y";
49	greg	1.1
50			int nowarn = 0; /* no warning messages? */
51
52	greg	1.18	int xmax = 0, ymax = 0; /* input resolution */
53	greg	1.9
54	greg	1.18	int xscan, yscan; /* input position */
55	greg	1.1
56	greg	1.18	int xres, yres; /* output resolution */
57	greg	1.1
58	greg	1.18	int xpos, ypos; /* output position */
59
60	greg	1.10	int wrongformat = 0;
61	greg	1.1
62	greg	1.19	FILE *popen();
63	greg	1.10
64	greg	1.19
65	greg	1.1	main(argc, argv)
66			int argc;
67			char *argv[];
68			{
69	greg	1.18	int original;
70	greg	1.3	double f;
71	greg	1.14	int a, i;
72	greg	1.15	/* scan options */
73			for (a = 1; a < argc; a++) {
74	greg	1.1	if (argv[a][0] == '-')
75			switch (argv[a][1]) {
76			case 'x':
77			case 'y':
78	greg	1.18	a++;
79	greg	1.15	continue;
80	greg	1.1	case 'w':
81			nowarn = !nowarn;
82	greg	1.15	continue;
83	greg	1.1	case 'f':
84			case 'e':
85	greg	1.16	a++;
86	greg	1.15	continue;
87	greg	1.1	}
88	greg	1.15	break;
89			}
90			/* process files */
91	greg	1.17	for (nfiles = 0; nfiles < MAXINP; nfiles++) {
92	greg	1.3	setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
93	greg	1.17	setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
94			}
95	greg	1.1	nfiles = 0;
96	greg	1.18	original = 0;
97	greg	1.1	for ( ; a < argc; a++) {
98			if (nfiles >= MAXINP) {
99			eputs(argv[0]);
100			eputs(": too many picture files\n");
101			quit(1);
102			}
103	greg	1.3	if (argv[a][0] == '-')
104			switch (argv[a][1]) {
105			case '\0':
106			input[nfiles].name = "<stdin>";
107			input[nfiles].fp = stdin;
108			break;
109	greg	1.17	case 'o':
110			original++;
111			break;
112	greg	1.3	case 's':
113			f = atof(argv[++a]);
114			scalecolor(input[nfiles].coef, f);
115			continue;
116			case 'c':
117			colval(input[nfiles].coef,RED)*=atof(argv[++a]);
118			colval(input[nfiles].coef,GRN)*=atof(argv[++a]);
119			colval(input[nfiles].coef,BLU)*=atof(argv[++a]);
120			continue;
121			default:
122			goto usage;
123			}
124			else {
125	greg	1.1	input[nfiles].name = argv[a];
126	greg	1.19	input[nfiles].fp = argv[a][0]=='!' ?
127			popen(argv[a]+1, "r") :
128			fopen(argv[a], "r");
129	greg	1.1	if (input[nfiles].fp == NULL) {
130	greg	1.6	perror(argv[a]);
131	greg	1.1	quit(1);
132			}
133			}
134	greg	1.16	checkfile();
135	greg	1.18	if (original) {
136			colval(input[nfiles].coef,RED) /=
137			colval(input[nfiles].expos,RED);
138			colval(input[nfiles].coef,GRN) /=
139			colval(input[nfiles].expos,GRN);
140			colval(input[nfiles].coef,BLU) /=
141			colval(input[nfiles].expos,BLU);
142			}
143			nfiles++;
144	greg	1.17	original = 0;
145	greg	1.15	}
146	greg	1.18	init(); /* set constants */
147	greg	1.15	/* go back and get expressions */
148			for (a = 1; a < argc; a++) {
149			if (argv[a][0] == '-')
150			switch (argv[a][1]) {
151			case 'x':
152	greg	1.21	varset(vxres, ':', eval(argv[++a]));
153	greg	1.18	continue;
154	greg	1.15	case 'y':
155	greg	1.21	varset(vyres, ':', eval(argv[++a]));
156	greg	1.16	continue;
157	greg	1.15	case 'w':
158			continue;
159			case 'f':
160			fcompile(argv[++a]);
161			continue;
162			case 'e':
163			scompile(argv[++a], NULL, 0);
164			continue;
165			}
166			break;
167			}
168	greg	1.18	/* set/get output resolution */
169			if (!vardefined(vxres))
170			varset(vxres, ':', (double)xmax);
171			if (!vardefined(vyres))
172			varset(vyres, ':', (double)ymax);
173			xres = varvalue(vxres) + .5;
174			yres = varvalue(vyres) + .5;
175			if (xres <= 0 \|\| yres <= 0) {
176			eputs(argv[0]);
177			eputs(": illegal output resolution\n");
178			quit(1);
179			}
180	greg	1.15	/* complete header */
181			printargs(argc, argv, stdout);
182			fputformat(COLRFMT, stdout);
183			putchar('\n');
184			fputresolu(YMAJOR\|YDECR, xres, yres, stdout);
185			/* combine pictures */
186			combine();
187			quit(0);
188			usage:
189			eputs("Usage: ");
190			eputs(argv[0]);
191			eputs(
192	greg	1.20	" [-w][-x xr][-y yr][-e expr][-f file] [ [-s f][-c r g b] pic ..]\n");
193	greg	1.15	quit(1);
194			}
195
196
197			tputs(s) /* put out string preceded by a tab */
198			char *s;
199			{
200			char fmt[32];
201			double d;
202			COLOR ctmp;
203
204			if (isformat(s)) { /* check format */
205			formatval(fmt, s);
206			wrongformat = strcmp(fmt, COLRFMT);
207	greg	1.17	return; /* don't echo */
208			}
209			if (isexpos(s)) { /* exposure */
210			d = exposval(s);
211			scalecolor(input[nfiles].expos, d);
212			} else if (iscolcor(s)) { /* color correction */
213	greg	1.15	colcorval(ctmp, s);
214	greg	1.17	multcolor(input[nfiles].expos, ctmp);
215	greg	1.15	}
216	greg	1.17	/* echo line */
217			putchar('\t');
218			fputs(s, stdout);
219	greg	1.16	}
220	greg	1.15
221	greg	1.16
222			checkfile() /* ready a file */
223			{
224	greg	1.18	int xinp, yinp;
225	greg	1.16	register int i;
226			/* process header */
227			fputs(input[nfiles].name, stdout);
228			fputs(":\n", stdout);
229			getheader(input[nfiles].fp, tputs, NULL);
230			if (wrongformat) {
231			eputs(input[nfiles].name);
232			eputs(": not in Radiance picture format\n");
233			quit(1);
234			}
235	greg	1.18	if (fgetresolu(&xinp, &yinp, input[nfiles].fp) != (YMAJOR\|YDECR)) {
236	greg	1.16	eputs(input[nfiles].name);
237			eputs(": bad picture size\n");
238			quit(1);
239			}
240	greg	1.18	if (xmax == 0 && ymax == 0) {
241			xmax = xinp;
242			ymax = yinp;
243			} else if (xinp != xmax \|\| yinp != ymax) {
244	greg	1.16	eputs(input[nfiles].name);
245			eputs(": resolution mismatch\n");
246			quit(1);
247			}
248			/* allocate scanlines */
249			for (i = 0; i < WINSIZ; i++)
250	greg	1.18	input[nfiles].scan[i] = (COLOR )emalloc(xmaxsizeof(COLOR));
251	greg	1.15	}
252
253
254	greg	1.18	init() /* perform final setup */
255	greg	1.15	{
256	greg	1.17	double l_colin(), l_expos();
257	greg	1.16	register int i;
258	greg	1.15	/* define constants */
259			varset(vnfiles, ':', (double)nfiles);
260	greg	1.18	varset(vxmax, ':', (double)xmax);
261			varset(vymax, ':', (double)ymax);
262	greg	1.15	/* set functions */
263			for (i = 0; i < 3; i++) {
264	greg	1.17	funset(vcolexp[i], 1, ':', l_expos);
265	greg	1.15	funset(vcolin[i], 1, '=', l_colin);
266			}
267	greg	1.17	funset(vbrtexp, 1, ':', l_expos);
268	greg	1.15	funset(vbrtin, 1, '=', l_colin);
269	greg	1.1	}
270
271
272			combine() /* combine pictures */
273			{
274	greg	1.8	EPNODE coldef[3], brtdef;
275	greg	1.1	COLOR *scanout;
276	greg	1.8	double d;
277	greg	1.1	register int i, j;
278			/* check defined variables */
279	greg	1.4	for (j = 0; j < 3; j++) {
280			if (vardefined(vcolout[j]))
281			coldef[j] = eparse(vcolout[j]);
282			else
283			coldef[j] = NULL;
284			}
285	greg	1.8	if (vardefined(vbrtout))
286			brtdef = eparse(vbrtout);
287			else
288			brtdef = NULL;
289	greg	1.1	/* allocate scanline */
290			scanout = (COLOR )emalloc(xressizeof(COLOR));
291	greg	1.18	/* set input position */
292			yscan = ymax+MIDSCN;
293	greg	1.1	/* combine files */
294			for (ypos = yres-1; ypos >= 0; ypos--) {
295	greg	1.14	advance();
296	greg	1.11	varset(vypos, '=', (double)ypos);
297	greg	1.8	for (xpos = 0; xpos < xres; xpos++) {
298	greg	1.18	xscan = (long)xpos*xmax/xres;
299	greg	1.11	varset(vxpos, '=', (double)xpos);
300	greg	1.8	eclock++;
301			if (brtdef != NULL) {
302			d = evalue(brtdef);
303			if (d < 0.0)
304			d = 0.0;
305			setcolor(scanout[xpos], d, d, d);
306			} else {
307			for (j = 0; j < 3; j++) {
308			if (coldef[j] != NULL) {
309	greg	1.13	d = evalue(coldef[j]);
310	greg	1.8	} else {
311	greg	1.13	d = 0.0;
312	greg	1.8	for (i = 0; i < nfiles; i++)
313	greg	1.18	d += colval(input[i].scan[MIDSCN][xscan],j);
314	greg	1.1	}
315	greg	1.13	if (d < 0.0)
316			d = 0.0;
317			colval(scanout[xpos],j) = d;
318	greg	1.8	}
319	greg	1.1	}
320	greg	1.8	}
321			if (fwritescan(scanout, xres, stdout) < 0) {
322			perror("write error");
323			quit(1);
324			}
325	greg	1.1	}
326			efree(scanout);
327			}
328
329
330	greg	1.18	advance() /* read in data for next scanline */
331	greg	1.14	{
332	greg	1.18	int ytarget;
333	greg	1.14	register COLOR *st;
334			register int i, j;
335
336	greg	1.18	for (ytarget = (long)ypos*ymax/yres; yscan > ytarget; yscan--)
337			for (i = 0; i < nfiles; i++) {
338			st = input[i].scan[WINSIZ-1];
339			for (j = WINSIZ-1; j > 0; j--) /* rotate window */
340			input[i].scan[j] = input[i].scan[j-1];
341			input[i].scan[0] = st;
342			if (yscan <= MIDSCN) /* hit bottom? */
343			continue;
344			if (freadscan(st, xmax, input[i].fp) < 0) { /* read */
345			eputs(input[i].name);
346			eputs(": read error\n");
347			quit(1);
348			}
349			for (j = 0; j < xmax; j++) /* adjust color */
350			multcolor(st[j], input[i].coef);
351	greg	1.14	}
352			}
353
354
355	greg	1.1	double
356	greg	1.17	l_expos(nam) /* return picture exposure */
357	greg	1.15	register char *nam;
358	greg	1.1	{
359	greg	1.15	register int fn, n;
360	greg	1.14
361	greg	1.18	fn = argument(1) - .5;
362			if (fn < 0 \|\| fn >= nfiles)
363			return(1.0);
364	greg	1.17	if (nam == vbrtexp)
365			return(bright(input[fn].expos));
366	greg	1.15	n = 3;
367			while (n--)
368	greg	1.17	if (nam == vcolexp[n])
369			return(colval(input[fn].expos,n));
370			eputs("Bad call to l_expos()!\n");
371	greg	1.15	quit(1);
372			}
373
374
375			double
376			l_colin(nam) /* return color value for picture */
377			register char *nam;
378			{
379			int fn;
380			register int n, xoff, yoff;
381			double d;
382
383	greg	1.16	d = argument(1);
384			if (d > -.5 && d < .5)
385			return((double)nfiles);
386			fn = d - .5;
387			if (fn < 0 \|\| fn >= nfiles) {
388	greg	1.15	errno = EDOM;
389			return(0.0);
390			}
391	greg	1.14	xoff = yoff = 0;
392			n = nargum();
393			if (n >= 2) {
394			d = argument(2);
395			if (d < 0.0) {
396			xoff = d-.5;
397	greg	1.18	if (xscan+xoff < 0)
398			xoff = -xscan;
399	greg	1.14	} else {
400			xoff = d+.5;
401	greg	1.18	if (xscan+xoff >= xmax)
402			xoff = xmax-1-xscan;
403	greg	1.14	}
404			}
405			if (n >= 3) {
406			d = argument(3);
407			if (d < 0.0) {
408			yoff = d-.5;
409			if (yoff+MIDSCN < 0)
410			yoff = -MIDSCN;
411	greg	1.18	if (yscan+yoff < 0)
412			yoff = -yscan;
413	greg	1.14	} else {
414			yoff = d+.5;
415			if (yoff+MIDSCN >= WINSIZ)
416			yoff = WINSIZ-1-MIDSCN;
417	greg	1.18	if (yscan+yoff >= ymax)
418			yoff = ymax-1-yscan;
419	greg	1.14	}
420			}
421	greg	1.15	if (nam == vbrtin)
422	greg	1.18	return(bright(input[fn].scan[MIDSCN+yoff][xscan+xoff]));
423	greg	1.15	n = 3;
424			while (n--)
425			if (nam == vcolin[n])
426	greg	1.18	return(colval(input[fn].scan[MIDSCN+yoff][xscan+xoff],n));
427	greg	1.15	eputs("Bad call to l_colin()!\n");
428			quit(1);
429	greg	1.1	}
430
431
432			wputs(msg)
433			char *msg;
434			{
435			if (!nowarn)
436			eputs(msg);
437			}
438
439
440			eputs(msg)
441			char *msg;
442			{
443			fputs(msg, stderr);
444			}
445
446
447			quit(code)
448			int code;
449			{
450			exit(code);
451			}