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>

#ifdef MSDOS
#include <fcntl.h>
#endif

#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();

extern char     *emalloc();


main(argc, argv)
int     argc;
char    *argv[];
{
        int     original;
        double  f;
        int     a, i;
#ifdef MSDOS
        extern int  _fmode;
        _fmode = O_BINARY;
        setmode(fileno(stdin), O_BINARY);
        setmode(fileno(stdout), O_BINARY);
#endif
                                                /* 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:	2.7
Committed:	Mon Sep 21 12:13:48 1992 UTC (31 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.6:	+12 -0 lines
Log Message:	Changes for PC port
#	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	greg	2.7	#ifdef MSDOS
16			#include <fcntl.h>
17			#endif
18
19	greg	1.1	#include <errno.h>
20
21			#include "color.h"
22
23	greg	1.23	#include "resolu.h"
24
25	greg	1.1	#include "calcomp.h"
26
27	greg	1.6	#define MAXINP 32 /* maximum number of input files */
28	greg	1.14	#define WINSIZ 9 /* scanline window size */
29			#define MIDSCN 4 /* current scan position */
30	greg	1.1
31			struct {
32	greg	1.19	char name; / file or command name */
33	greg	1.1	FILE fp; / stream pointer */
34	greg	1.14	COLOR scan[WINSIZ]; / input scanline window */
35	greg	1.3	COLOR coef; /* coefficient */
36	greg	1.17	COLOR expos; /* recorded exposure */
37	greg	1.1	} input[MAXINP]; /* input pictures */
38
39			int nfiles; /* number of input files */
40
41	greg	2.6	char Command[] = "<Command>";
42	greg	1.21	char vcolin[3][4] = {"ri", "gi", "bi"};
43			char vcolout[3][4] = {"ro", "go", "bo"};
44	greg	1.15	char vbrtin[] = "li";
45			char vbrtout[] = "lo";
46	greg	1.21	char vcolexp[3][4] = {"re", "ge", "be"};
47	greg	1.17	char vbrtexp[] = "le";
48	greg	1.1
49	greg	1.18	char vnfiles[] = "nfiles";
50			char vxmax[] = "xmax";
51			char vymax[] = "ymax";
52			char vxres[] = "xres";
53			char vyres[] = "yres";
54			char vxpos[] = "x";
55			char vypos[] = "y";
56	greg	1.1
57			int nowarn = 0; /* no warning messages? */
58
59	greg	1.18	int xmax = 0, ymax = 0; /* input resolution */
60	greg	1.9
61	greg	1.18	int xscan, yscan; /* input position */
62	greg	1.1
63	greg	1.18	int xres, yres; /* output resolution */
64	greg	1.1
65	greg	1.18	int xpos, ypos; /* output position */
66
67	greg	1.10	int wrongformat = 0;
68	greg	1.1
69	greg	1.19	FILE *popen();
70	greg	1.10
71	greg	2.7	extern char *emalloc();
72	greg	1.19
73	greg	2.7
74	greg	1.1	main(argc, argv)
75			int argc;
76			char *argv[];
77			{
78	greg	1.18	int original;
79	greg	1.3	double f;
80	greg	1.14	int a, i;
81	greg	2.7	#ifdef MSDOS
82			extern int _fmode;
83			_fmode = O_BINARY;
84			setmode(fileno(stdin), O_BINARY);
85			setmode(fileno(stdout), O_BINARY);
86			#endif
87	greg	1.15	/* scan options */
88			for (a = 1; a < argc; a++) {
89	greg	1.1	if (argv[a][0] == '-')
90			switch (argv[a][1]) {
91			case 'x':
92			case 'y':
93	greg	1.18	a++;
94	greg	1.15	continue;
95	greg	1.1	case 'w':
96			nowarn = !nowarn;
97	greg	1.15	continue;
98	greg	1.1	case 'f':
99			case 'e':
100	greg	1.16	a++;
101	greg	1.15	continue;
102	greg	1.1	}
103	greg	1.15	break;
104			}
105			/* process files */
106	greg	1.17	for (nfiles = 0; nfiles < MAXINP; nfiles++) {
107	greg	1.3	setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
108	greg	1.17	setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
109			}
110	greg	1.1	nfiles = 0;
111	greg	1.18	original = 0;
112	greg	1.1	for ( ; a < argc; a++) {
113			if (nfiles >= MAXINP) {
114			eputs(argv[0]);
115			eputs(": too many picture files\n");
116			quit(1);
117			}
118	greg	1.3	if (argv[a][0] == '-')
119			switch (argv[a][1]) {
120			case '\0':
121			input[nfiles].name = "<stdin>";
122			input[nfiles].fp = stdin;
123			break;
124	greg	1.17	case 'o':
125			original++;
126	greg	1.22	continue;
127	greg	1.3	case 's':
128			f = atof(argv[++a]);
129			scalecolor(input[nfiles].coef, f);
130			continue;
131			case 'c':
132			colval(input[nfiles].coef,RED)*=atof(argv[++a]);
133			colval(input[nfiles].coef,GRN)*=atof(argv[++a]);
134			colval(input[nfiles].coef,BLU)*=atof(argv[++a]);
135			continue;
136			default:
137			goto usage;
138			}
139			else {
140	greg	2.2	if (argv[a][0] == '!') {
141	greg	2.6	input[nfiles].name = Command;
142	greg	2.2	input[nfiles].fp = popen(argv[a]+1, "r");
143			} else {
144			input[nfiles].name = argv[a];
145			input[nfiles].fp = fopen(argv[a], "r");
146			}
147	greg	1.1	if (input[nfiles].fp == NULL) {
148	greg	1.6	perror(argv[a]);
149	greg	1.1	quit(1);
150			}
151			}
152	greg	1.16	checkfile();
153	greg	1.18	if (original) {
154			colval(input[nfiles].coef,RED) /=
155			colval(input[nfiles].expos,RED);
156			colval(input[nfiles].coef,GRN) /=
157			colval(input[nfiles].expos,GRN);
158			colval(input[nfiles].coef,BLU) /=
159			colval(input[nfiles].expos,BLU);
160			}
161			nfiles++;
162	greg	1.17	original = 0;
163	greg	1.15	}
164	greg	1.18	init(); /* set constants */
165	greg	1.15	/* go back and get expressions */
166			for (a = 1; a < argc; a++) {
167			if (argv[a][0] == '-')
168			switch (argv[a][1]) {
169			case 'x':
170	greg	1.21	varset(vxres, ':', eval(argv[++a]));
171	greg	1.18	continue;
172	greg	1.15	case 'y':
173	greg	1.21	varset(vyres, ':', eval(argv[++a]));
174	greg	1.16	continue;
175	greg	1.15	case 'w':
176			continue;
177			case 'f':
178			fcompile(argv[++a]);
179			continue;
180			case 'e':
181			scompile(argv[++a], NULL, 0);
182			continue;
183			}
184			break;
185			}
186	greg	1.18	/* set/get output resolution */
187			if (!vardefined(vxres))
188			varset(vxres, ':', (double)xmax);
189			if (!vardefined(vyres))
190			varset(vyres, ':', (double)ymax);
191			xres = varvalue(vxres) + .5;
192			yres = varvalue(vyres) + .5;
193			if (xres <= 0 \|\| yres <= 0) {
194			eputs(argv[0]);
195			eputs(": illegal output resolution\n");
196			quit(1);
197			}
198	greg	1.15	/* complete header */
199			printargs(argc, argv, stdout);
200			fputformat(COLRFMT, stdout);
201			putchar('\n');
202	greg	1.23	fprtresolu(xres, yres, stdout);
203	greg	1.15	/* combine pictures */
204			combine();
205			quit(0);
206			usage:
207			eputs("Usage: ");
208			eputs(argv[0]);
209			eputs(
210	greg	1.20	" [-w][-x xr][-y yr][-e expr][-f file] [ [-s f][-c r g b] pic ..]\n");
211	greg	1.15	quit(1);
212			}
213
214
215			tputs(s) /* put out string preceded by a tab */
216			char *s;
217			{
218			char fmt[32];
219			double d;
220			COLOR ctmp;
221
222			if (isformat(s)) { /* check format */
223			formatval(fmt, s);
224			wrongformat = strcmp(fmt, COLRFMT);
225	greg	1.17	return; /* don't echo */
226			}
227			if (isexpos(s)) { /* exposure */
228			d = exposval(s);
229			scalecolor(input[nfiles].expos, d);
230			} else if (iscolcor(s)) { /* color correction */
231	greg	1.15	colcorval(ctmp, s);
232	greg	1.17	multcolor(input[nfiles].expos, ctmp);
233	greg	1.15	}
234	greg	1.17	/* echo line */
235			putchar('\t');
236			fputs(s, stdout);
237	greg	1.16	}
238	greg	1.15
239	greg	1.16
240			checkfile() /* ready a file */
241			{
242	greg	1.18	int xinp, yinp;
243	greg	1.16	register int i;
244			/* process header */
245			fputs(input[nfiles].name, stdout);
246			fputs(":\n", stdout);
247			getheader(input[nfiles].fp, tputs, NULL);
248			if (wrongformat) {
249			eputs(input[nfiles].name);
250			eputs(": not in Radiance picture format\n");
251			quit(1);
252			}
253	greg	1.23	if (fgetresolu(&xinp, &yinp, input[nfiles].fp) < 0) {
254	greg	1.16	eputs(input[nfiles].name);
255			eputs(": bad picture size\n");
256			quit(1);
257			}
258	greg	1.18	if (xmax == 0 && ymax == 0) {
259			xmax = xinp;
260			ymax = yinp;
261			} else if (xinp != xmax \|\| yinp != ymax) {
262	greg	1.16	eputs(input[nfiles].name);
263			eputs(": resolution mismatch\n");
264			quit(1);
265			}
266			/* allocate scanlines */
267			for (i = 0; i < WINSIZ; i++)
268	greg	1.18	input[nfiles].scan[i] = (COLOR )emalloc(xmaxsizeof(COLOR));
269	greg	1.15	}
270
271
272	greg	1.18	init() /* perform final setup */
273	greg	1.15	{
274	greg	1.17	double l_colin(), l_expos();
275	greg	1.16	register int i;
276	greg	1.15	/* define constants */
277			varset(vnfiles, ':', (double)nfiles);
278	greg	1.18	varset(vxmax, ':', (double)xmax);
279			varset(vymax, ':', (double)ymax);
280	greg	1.15	/* set functions */
281			for (i = 0; i < 3; i++) {
282	greg	1.17	funset(vcolexp[i], 1, ':', l_expos);
283	greg	1.15	funset(vcolin[i], 1, '=', l_colin);
284			}
285	greg	1.17	funset(vbrtexp, 1, ':', l_expos);
286	greg	1.15	funset(vbrtin, 1, '=', l_colin);
287	greg	1.1	}
288
289
290			combine() /* combine pictures */
291			{
292	greg	1.8	EPNODE coldef[3], brtdef;
293	greg	1.1	COLOR *scanout;
294	greg	1.8	double d;
295	greg	1.1	register int i, j;
296			/* check defined variables */
297	greg	1.4	for (j = 0; j < 3; j++) {
298			if (vardefined(vcolout[j]))
299			coldef[j] = eparse(vcolout[j]);
300			else
301			coldef[j] = NULL;
302			}
303	greg	1.8	if (vardefined(vbrtout))
304			brtdef = eparse(vbrtout);
305			else
306			brtdef = NULL;
307	greg	1.1	/* allocate scanline */
308			scanout = (COLOR )emalloc(xressizeof(COLOR));
309	greg	1.18	/* set input position */
310			yscan = ymax+MIDSCN;
311	greg	1.1	/* combine files */
312			for (ypos = yres-1; ypos >= 0; ypos--) {
313	greg	1.14	advance();
314	greg	1.11	varset(vypos, '=', (double)ypos);
315	greg	1.8	for (xpos = 0; xpos < xres; xpos++) {
316	greg	1.18	xscan = (long)xpos*xmax/xres;
317	greg	1.11	varset(vxpos, '=', (double)xpos);
318	greg	1.8	eclock++;
319			if (brtdef != NULL) {
320			d = evalue(brtdef);
321			if (d < 0.0)
322			d = 0.0;
323			setcolor(scanout[xpos], d, d, d);
324			} else {
325			for (j = 0; j < 3; j++) {
326			if (coldef[j] != NULL) {
327	greg	1.13	d = evalue(coldef[j]);
328	greg	1.8	} else {
329	greg	1.13	d = 0.0;
330	greg	1.8	for (i = 0; i < nfiles; i++)
331	greg	1.18	d += colval(input[i].scan[MIDSCN][xscan],j);
332	greg	1.1	}
333	greg	1.13	if (d < 0.0)
334			d = 0.0;
335			colval(scanout[xpos],j) = d;
336	greg	1.8	}
337	greg	1.1	}
338	greg	1.8	}
339			if (fwritescan(scanout, xres, stdout) < 0) {
340			perror("write error");
341			quit(1);
342			}
343	greg	1.1	}
344			efree(scanout);
345			}
346
347
348	greg	1.18	advance() /* read in data for next scanline */
349	greg	1.14	{
350	greg	2.4	extern double fabs();
351	greg	1.18	int ytarget;
352	greg	1.14	register COLOR *st;
353			register int i, j;
354
355	greg	1.18	for (ytarget = (long)ypos*ymax/yres; yscan > ytarget; yscan--)
356			for (i = 0; i < nfiles; i++) {
357			st = input[i].scan[WINSIZ-1];
358			for (j = WINSIZ-1; j > 0; j--) /* rotate window */
359			input[i].scan[j] = input[i].scan[j-1];
360			input[i].scan[0] = st;
361			if (yscan <= MIDSCN) /* hit bottom? */
362			continue;
363	greg	2.4	if (freadscan(st, xmax, input[i].fp) < 0) { /* read */
364	greg	1.18	eputs(input[i].name);
365			eputs(": read error\n");
366			quit(1);
367			}
368	greg	2.4	if (fabs(colval(input[i].coef,RED)-1.0) > 1e-3 \|\|
369			fabs(colval(input[i].coef,GRN)-1.0) > 1e-3 \|\|
370			fabs(colval(input[i].coef,BLU)-1.0) > 1e-3)
371			for (j = 0; j < xmax; j++) /* adjust color */
372			multcolor(st[j], input[i].coef);
373	greg	1.14	}
374			}
375
376
377	greg	1.1	double
378	greg	1.17	l_expos(nam) /* return picture exposure */
379	greg	1.15	register char *nam;
380	greg	1.1	{
381	greg	1.15	register int fn, n;
382	greg	1.14
383	greg	1.18	fn = argument(1) - .5;
384			if (fn < 0 \|\| fn >= nfiles)
385			return(1.0);
386	greg	1.17	if (nam == vbrtexp)
387			return(bright(input[fn].expos));
388	greg	1.15	n = 3;
389			while (n--)
390	greg	1.17	if (nam == vcolexp[n])
391			return(colval(input[fn].expos,n));
392			eputs("Bad call to l_expos()!\n");
393	greg	1.15	quit(1);
394			}
395
396
397			double
398			l_colin(nam) /* return color value for picture */
399			register char *nam;
400			{
401			int fn;
402			register int n, xoff, yoff;
403			double d;
404
405	greg	1.16	d = argument(1);
406			if (d > -.5 && d < .5)
407			return((double)nfiles);
408			fn = d - .5;
409			if (fn < 0 \|\| fn >= nfiles) {
410	greg	1.15	errno = EDOM;
411			return(0.0);
412			}
413	greg	1.14	xoff = yoff = 0;
414			n = nargum();
415			if (n >= 2) {
416			d = argument(2);
417			if (d < 0.0) {
418			xoff = d-.5;
419	greg	1.18	if (xscan+xoff < 0)
420			xoff = -xscan;
421	greg	1.14	} else {
422			xoff = d+.5;
423	greg	1.18	if (xscan+xoff >= xmax)
424			xoff = xmax-1-xscan;
425	greg	1.14	}
426			}
427			if (n >= 3) {
428			d = argument(3);
429			if (d < 0.0) {
430			yoff = d-.5;
431			if (yoff+MIDSCN < 0)
432			yoff = -MIDSCN;
433	greg	1.18	if (yscan+yoff < 0)
434			yoff = -yscan;
435	greg	1.14	} else {
436			yoff = d+.5;
437			if (yoff+MIDSCN >= WINSIZ)
438			yoff = WINSIZ-1-MIDSCN;
439	greg	1.18	if (yscan+yoff >= ymax)
440			yoff = ymax-1-yscan;
441	greg	1.14	}
442			}
443	greg	1.15	if (nam == vbrtin)
444	greg	1.18	return(bright(input[fn].scan[MIDSCN+yoff][xscan+xoff]));
445	greg	1.15	n = 3;
446			while (n--)
447			if (nam == vcolin[n])
448	greg	1.18	return(colval(input[fn].scan[MIDSCN+yoff][xscan+xoff],n));
449	greg	1.15	eputs("Bad call to l_colin()!\n");
450			quit(1);
451	greg	1.1	}
452
453
454			wputs(msg)
455			char *msg;
456			{
457			if (!nowarn)
458			eputs(msg);
459			}
460
461
462			eputs(msg)
463			char *msg;
464			{
465			fputs(msg, stderr);
466			}
467
468
469	greg	2.4	quit(code) /* exit gracefully */
470			int code;
471			{
472	greg	2.5	register int i;
473			/* close input files */
474			for (i = 0; i < nfiles; i++)
475	greg	2.6	if (input[i].name == Command)
476			pclose(input[i].fp);
477			else
478			fclose(input[i].fp);
479	greg	1.1	exit(code);
480			}