src/util/glareval.c

#ifndef lint
static const char       RCSid[] = "$Id: glareval.c,v 2.9 2003/06/30 14:59:13 schorsch Exp $";
#endif
/*
 * Compute pixels for glare calculation
 */

#include "copyright.h"

#include <stdlib.h>
#include <string.h>

#include "rtprocess.h" /* Windows: must come first because of conflicts */
#include "glare.h"

                                        /* maximum rtrace buffer size */
#define MAXPIX          (4096/(6*sizeof(float)))

#define MAXSBUF         786432  /* maximum total size of scanline buffer */
#define HSIZE           317     /* size of scanline hash table */
#define NRETIRE         16      /* number of scanlines to retire at once */

static SUBPROC  rt_pd = SP_INACTIVE; /* process id & descriptors for rtrace */

FILE    *pictfp = NULL;         /* picture file pointer */
double  exposure;               /* picture exposure */
int     pxsiz, pysiz;           /* picture dimensions */

static int      curpos;         /* current scanline */
static long     *scanpos;       /* scanline positions */

typedef struct scan {
        int     y;              /* scanline position */
        long    lused;          /* for LRU replacement */
        struct scan     *next;  /* next in this hash or free list */
        /* followed by the scanline data */
} SCAN;                 /* buffered scanline */

#define scandata(sl)    ((COLR *)((sl)+1))
#define shash(y)        ((y)%HSIZE)

static int      maxpix;         /* maximum number of pixels to buffer */

static SCAN     *freelist;              /* scanline free list */
static SCAN     *hashtab[HSIZE];        /* scanline hash table */

static long     scanbufsiz;             /* size of allocated scanline buffer */

static long     ncall = 0L;     /* number of calls to getpictscan */
static long     nread = 0L;     /* number of scanlines read */
static long     nrecl = 0L;     /* number of scanlines reclaimed */

static int      wrongformat = 0;

SCAN    *scanretire();

extern long     ftell();


SCAN *
claimscan(y)                    /* claim scanline from buffers */
int     y;
{
        int     hi = shash(y);
        SCAN    *slast;
        register SCAN   *sl;

        for (sl = hashtab[hi]; sl != NULL; sl = sl->next)
                if (sl->y == y)                         /* active scanline */
                        return(sl);
        for (slast = NULL, sl = freelist; sl != NULL; slast = sl, sl = sl->next)
                if (sl->y == -1 || sl->y == y || sl->next == NULL) {
                        if (slast == NULL)              /* remove from free */
                                freelist = sl->next;
                        else
                                slast->next = sl->next;
                        if (sl->y == y) {               /* reclaim */
                                sl->next = hashtab[hi];
                                hashtab[hi] = sl;
                                nrecl++;
                        }
                        return(sl);
                }
        return(scanretire());           /* need more free scanlines */
}


COLR *
getpictscan(y)                  /* get picture scanline */
int     y;
{
        register SCAN   *sl;
        register int    i;
                                        /* first check our buffers */
        sl = claimscan(y);
        if (sl == NULL)
                memerr("claimscan()");
        sl->lused = ncall++;
        if (sl->y == y)                 /* scan hit */
                return(scandata(sl));
                                        /* else read in replacement */
        if (scanpos[y] < 0) {                   /* need to search */
                for (i = y+1; i < curpos; i++)
                        if (scanpos[i] >= 0) {
                                if (fseek(pictfp, scanpos[i], 0) < 0)
                                        goto seekerr;
                                curpos = i;
                                break;
                        }
                while (curpos >= y) {
                        scanpos[curpos] = ftell(pictfp);
                        if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0)
                                goto readerr;
                        nread++;
                        curpos--;
                }
        } else {
                if (curpos != y && fseek(pictfp, scanpos[y], 0) < 0)
                        goto seekerr;
                if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0)
                        goto readerr;
                nread++;
                curpos = y-1;
        }
        sl->y = y;
        i = shash(y);                   /* add to hash list */
        sl->next = hashtab[i];
        hashtab[i] = sl;
        return(scandata(sl));
readerr:
        fprintf(stderr, "%s: picture read error\n", progname);
        exit(1);
seekerr:
        fprintf(stderr, "%s: picture seek error\n", progname);
        exit(1);
}


#ifdef DEBUG
pict_stats()                    /* print out picture read statistics */
{
        static long     lastcall = 0L;  /* ncall at last report */
        static long     lastread = 0L;  /* nread at last report */
        static long     lastrecl = 0L;  /* nrecl at last report */

        if (ncall == lastcall)
                return;
        fprintf(stderr, "%s: %ld scanlines read (%ld reclaimed) in %ld calls\n",
                progname, nread-lastread, nrecl-lastrecl, ncall-lastcall);
        lastcall = ncall;
        lastread = nread;
        lastrecl = nrecl;
}
#endif


double
pict_val(vd)                    /* find picture value for view direction */
FVECT   vd;
{
        FVECT   pp;
        FVECT   ip;
        COLOR   res;

        if (pictfp == NULL)
                return(-1.0);
        pp[0] = pictview.vp[0] + vd[0];
        pp[1] = pictview.vp[1] + vd[1];
        pp[2] = pictview.vp[2] + vd[2];
        viewloc(ip, &pictview, pp);
        if (ip[2] <= FTINY || ip[0] < 0. || ip[0] >= 1. ||
                        ip[1] < 0. || ip[1] >= 1.)
                return(-1.0);
        colr_color(res, getpictscan((int)(ip[1]*pysiz))[(int)(ip[0]*pxsiz)]);
        return(luminance(res)/exposure);
}


double
getviewpix(vh, vv)              /* compute single view pixel */
int     vh, vv;
{
        FVECT   dir;
        float   rt_buf[12];
        double  res;

        if (compdir(dir, vh, vv) < 0)
                return(-1.0);
        npixinvw++;
        if ((res = pict_val(dir)) >= 0.0)
                return(res);
        if (rt_pd.r == -1) {
                npixmiss++;
                return(-1.0);
        }
        rt_buf[0] = ourview.vp[0];
        rt_buf[1] = ourview.vp[1];
        rt_buf[2] = ourview.vp[2];
        rt_buf[3] = dir[0];
        rt_buf[4] = dir[1];
        rt_buf[5] = dir[2];
        rt_compute(rt_buf, 1);
        return(luminance(rt_buf));
}


getviewspan(vv, vb)             /* compute a span of view pixels */
int     vv;
float   *vb;
{
        float   rt_buf[6*MAXPIX];       /* rtrace send/receive buffer */
        register int    n;              /* number of pixels in buffer */
        short   buf_vh[MAXPIX];         /* pixel positions */
        FVECT   dir;
        register int    vh;

#ifdef DEBUG
        if (verbose)
                fprintf(stderr, "%s: computing view span at %d...\n",
                                progname, vv);
#endif
        n = 0;
        for (vh = -hsize; vh <= hsize; vh++) {
                if (compdir(dir, vh, vv) < 0) {         /* not in view */
                        vb[vh+hsize] = -1.0;
                        continue;
                }
                npixinvw++;
                if ((vb[vh+hsize] = pict_val(dir)) >= 0.0)
                        continue;
                if (rt_pd.r == -1) {            /* missing information */
                        npixmiss++;
                        continue;
                }
                                                /* send to rtrace */
                if (n >= maxpix) {                      /* flush */
                        rt_compute(rt_buf, n);
                        while (n-- > 0)
                                vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n);
                }
                rt_buf[6*n] = ourview.vp[0];
                rt_buf[6*n+1] = ourview.vp[1];
                rt_buf[6*n+2] = ourview.vp[2];
                rt_buf[6*n+3] = dir[0];
                rt_buf[6*n+4] = dir[1];
                rt_buf[6*n+5] = dir[2];
                buf_vh[n++] = vh;
        }
#ifdef DEBUG
        if (verbose)
                pict_stats();
#endif
        if (n > 0) {                            /* process pending buffer */
                rt_compute(rt_buf, n);
                while (n-- > 0)
                        vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n);
        }
}


rt_compute(pb, np)              /* process buffer through rtrace */
float   *pb;
int     np;
{
#ifdef DEBUG
        if (verbose && np > 1)
                fprintf(stderr, "%s: sending %d samples to rtrace...\n",
                                progname, np);
#endif
        memset(pb+6*np, '\0', 6*sizeof(float));
        if (process(&rt_pd, (char *)pb, (char *)pb, 3*sizeof(float)*(np+1),
                        6*sizeof(float)*(np+1)) < 3*sizeof(float)*(np+1)) {
                fprintf(stderr, "%s: rtrace communication error\n",
                                progname);
                exit(1);
        }
}


int
getexpos(s)                     /* get exposure from header line */
char    *s;
{
        char    fmt[32];

        if (isexpos(s))
                exposure *= exposval(s);
        else if (isformat(s)) {
                formatval(fmt, s);
                wrongformat = strcmp(fmt, COLRFMT);
        }
        return(0);
}


open_pict(fn)                   /* open picture file */
char    *fn;
{
        if ((pictfp = fopen(fn, "r")) == NULL) {
                fprintf(stderr, "%s: cannot open\n", fn);
                exit(1);
        }
        exposure = 1.0;
        getheader(pictfp, getexpos, NULL);
        if (wrongformat || !fscnresolu(&pxsiz, &pysiz, pictfp)) {
                fprintf(stderr, "%s: incompatible picture format\n", fn);
                exit(1);
        }
        initscans();
}


close_pict()                    /* done with picture */
{
        if (pictfp == NULL)
                return;
        fclose(pictfp);
        donescans();
        pictfp = NULL;
}


fork_rtrace(av)                 /* open pipe and start rtrace */
char    *av[];
{
        int     rval;

        rval = open_process(&rt_pd, av);
        if (rval < 0) {
                perror(progname);
                exit(1);
        }
        if (rval == 0) {
                fprintf(stderr, "%s: command not found\n", av[0]);
                exit(1);
        }
        maxpix = rval/(6*sizeof(float));
        if (maxpix > MAXPIX)
                maxpix = MAXPIX;
        maxpix--;
}


done_rtrace()                   /* wait for rtrace to finish */
{
        int     status;

        status = close_process(&rt_pd);
        if (status > 0) {
                fprintf(stderr, "%s: bad status (%d) from rtrace\n",
                                progname, status);
                exit(1);
        }
        rt_pd.r = -1;
}


SCAN *
scanretire()                    /* retire old scanlines to free list */
{
        SCAN    *sold[NRETIRE];
        int     n;
        int     h;
        register SCAN   *sl;
        register int    i;
                                        /* grab the NRETIRE oldest scanlines */
        sold[n = 0] = NULL;
        for (h = 0; h < HSIZE; h++)
                for (sl = hashtab[h]; sl != NULL; sl = sl->next) {
                        for (i = n; i && sold[i-1]->lused > sl->lused; i--)
                                if (i < NRETIRE)
                                        sold[i] = sold[i-1];
                        if (i < NRETIRE) {
                                sold[i] = sl;
                                if (n < NRETIRE)        /* grow list */
                                        n++;
                        }
                }
                                        /* put scanlines into free list */
        for (i = 0; i < n; i++) {
                h = shash(sold[i]->y);
                sl = hashtab[h];
                if (sl == sold[i])
                        hashtab[h] = sl->next;
                else {
                        while (sl->next != sold[i])     /* IS in list */
                                sl = sl->next;
                        sl->next = sold[i]->next;
                }
                if (i > 0) {            /* save oldest as return value */
                        sold[i]->next = freelist;
                        freelist = sold[i];
                }
        }
        return(sold[0]);
}


static char     *scan_buf;


initscans()                             /* initialize scanline buffers */
{
        int     scansize;
        register SCAN   *ptr;
        register int    i;
                                        /* initialize positions */
        scanpos = (long *)bmalloc(pysiz*sizeof(long));
        if (scanpos == NULL)
                memerr("scanline positions");
        for (i = pysiz-1; i >= 0; i--)
                scanpos[i] = -1L;
        curpos = pysiz-1;
                                        /* clear hash table */
        for (i = 0; i < HSIZE; i++)
                hashtab[i] = NULL;
                                        /* allocate scanline buffers */
        scansize = sizeof(SCAN) + pxsiz*sizeof(COLR);
#ifdef ALIGNT
        scansize = scansize+(sizeof(ALIGNT)-1) & ~(sizeof(ALIGNT)-1);
#endif
        i = MAXSBUF / scansize;         /* compute number to allocate */
        if (i > HSIZE)
                i = HSIZE;
        scanbufsiz = i*scansize;
        scan_buf = bmalloc(scanbufsiz); /* get in one big chunk */
        if (scan_buf == NULL)
                memerr("scanline buffers");
        ptr = (SCAN *)scan_buf;
        freelist = NULL;                /* build our free list */
        while (i-- > 0) {
                ptr->y = -1;
                ptr->lused = -1;
                ptr->next = freelist;
                freelist = ptr;
                ptr = (SCAN *)((char *)ptr + scansize); /* beware of C bugs */
        }
}


donescans()                             /* free up scanlines */
{
        bfree(scan_buf, scanbufsiz);
        bfree((char *)scanpos, pysiz*sizeof(long));
}
Revision:	2.10
Committed:	Thu Jul 3 22:41:45 2003 UTC (20 years, 9 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
Changes since 2.9:	+2 -1 lines
Log Message:	Reduced compile problems on Windows.
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	schorsch	2.10	static const char RCSid[] = "$Id: glareval.c,v 2.9 2003/06/30 14:59:13 schorsch Exp $";
3	greg	1.1	#endif
4			/*
5			* Compute pixels for glare calculation
6			*/
7
8	schorsch	2.9	#include "copyright.h"
9
10	schorsch	2.10	#include <stdlib.h>
11	schorsch	2.9	#include <string.h>
12
13	schorsch	2.7	#include "rtprocess.h" /* Windows: must come first because of conflicts */
14	greg	1.1	#include "glare.h"
15	schorsch	2.7
16	greg	1.19	/* maximum rtrace buffer size */
17			#define MAXPIX (4096/(6*sizeof(float)))
18	greg	1.1
19	greg	1.16	#define MAXSBUF 786432 /* maximum total size of scanline buffer */
20	greg	1.9	#define HSIZE 317 /* size of scanline hash table */
21	greg	1.8	#define NRETIRE 16 /* number of scanlines to retire at once */
22	greg	1.1
23	schorsch	2.7	static SUBPROC rt_pd = SP_INACTIVE; /* process id & descriptors for rtrace */
24	greg	1.1
25			FILE pictfp = NULL; / picture file pointer */
26			double exposure; /* picture exposure */
27			int pxsiz, pysiz; /* picture dimensions */
28	greg	1.8
29			static int curpos; /* current scanline */
30			static long scanpos; / scanline positions */
31
32			typedef struct scan {
33			int y; /* scanline position */
34	greg	1.1	long lused; /* for LRU replacement */
35	greg	1.8	struct scan next; / next in this hash or free list */
36			/* followed by the scanline data */
37			} SCAN; /* buffered scanline */
38	greg	1.1
39	greg	1.8	#define scandata(sl) ((COLR *)((sl)+1))
40			#define shash(y) ((y)%HSIZE)
41
42	greg	1.19	static int maxpix; /* maximum number of pixels to buffer */
43
44	greg	1.8	static SCAN freelist; / scanline free list */
45			static SCAN hashtab[HSIZE]; / scanline hash table */
46
47	greg	2.2	static long scanbufsiz; /* size of allocated scanline buffer */
48
49	greg	1.2	static long ncall = 0L; /* number of calls to getpictscan */
50			static long nread = 0L; /* number of scanlines read */
51	greg	1.15	static long nrecl = 0L; /* number of scanlines reclaimed */
52	greg	1.1
53	greg	1.13	static int wrongformat = 0;
54
55	greg	1.8	SCAN *scanretire();
56
57	greg	1.5	extern long ftell();
58	greg	1.2
59	greg	1.5
60	greg	1.8	SCAN *
61			claimscan(y) /* claim scanline from buffers */
62			int y;
63			{
64			int hi = shash(y);
65			SCAN *slast;
66			register SCAN *sl;
67
68			for (sl = hashtab[hi]; sl != NULL; sl = sl->next)
69			if (sl->y == y) /* active scanline */
70			return(sl);
71			for (slast = NULL, sl = freelist; sl != NULL; slast = sl, sl = sl->next)
72			if (sl->y == -1 \|\| sl->y == y \|\| sl->next == NULL) {
73			if (slast == NULL) /* remove from free */
74			freelist = sl->next;
75			else
76			slast->next = sl->next;
77			if (sl->y == y) { /* reclaim */
78			sl->next = hashtab[hi];
79			hashtab[hi] = sl;
80	greg	1.15	nrecl++;
81	greg	1.8	}
82			return(sl);
83			}
84			return(scanretire()); /* need more free scanlines */
85			}
86
87
88	greg	1.1	COLR *
89			getpictscan(y) /* get picture scanline */
90			int y;
91			{
92	greg	1.8	register SCAN *sl;
93	greg	1.1	register int i;
94			/* first check our buffers */
95	greg	1.8	sl = claimscan(y);
96			if (sl == NULL)
97			memerr("claimscan()");
98			sl->lused = ncall++;
99			if (sl->y == y) /* scan hit */
100			return(scandata(sl));
101			/* else read in replacement */
102	greg	1.5	if (scanpos[y] < 0) { /* need to search */
103			for (i = y+1; i < curpos; i++)
104			if (scanpos[i] >= 0) {
105			if (fseek(pictfp, scanpos[i], 0) < 0)
106			goto seekerr;
107			curpos = i;
108			break;
109			}
110			while (curpos >= y) {
111	greg	1.1	scanpos[curpos] = ftell(pictfp);
112	greg	1.8	if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0)
113	greg	1.1	goto readerr;
114	greg	1.5	nread++;
115	greg	1.1	curpos--;
116			}
117	greg	1.5	} else {
118			if (curpos != y && fseek(pictfp, scanpos[y], 0) < 0)
119			goto seekerr;
120	greg	1.8	if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0)
121	greg	1.5	goto readerr;
122			nread++;
123			curpos = y-1;
124	greg	1.1	}
125	greg	1.8	sl->y = y;
126			i = shash(y); /* add to hash list */
127			sl->next = hashtab[i];
128			hashtab[i] = sl;
129			return(scandata(sl));
130	greg	1.1	readerr:
131			fprintf(stderr, "%s: picture read error\n", progname);
132			exit(1);
133	greg	1.5	seekerr:
134			fprintf(stderr, "%s: picture seek error\n", progname);
135			exit(1);
136	greg	1.1	}
137
138
139	greg	1.6	#ifdef DEBUG
140	greg	1.2	pict_stats() /* print out picture read statistics */
141			{
142			static long lastcall = 0L; /* ncall at last report */
143			static long lastread = 0L; /* nread at last report */
144	greg	1.15	static long lastrecl = 0L; /* nrecl at last report */
145	greg	1.2
146			if (ncall == lastcall)
147			return;
148	greg	1.15	fprintf(stderr, "%s: %ld scanlines read (%ld reclaimed) in %ld calls\n",
149			progname, nread-lastread, nrecl-lastrecl, ncall-lastcall);
150	greg	1.2	lastcall = ncall;
151			lastread = nread;
152	greg	1.15	lastrecl = nrecl;
153	greg	1.2	}
154	greg	1.6	#endif
155	greg	1.2
156
157	greg	1.1	double
158			pict_val(vd) /* find picture value for view direction */
159			FVECT vd;
160			{
161			FVECT pp;
162	greg	1.21	FVECT ip;
163	greg	1.1	COLOR res;
164
165			if (pictfp == NULL)
166			return(-1.0);
167			pp[0] = pictview.vp[0] + vd[0];
168			pp[1] = pictview.vp[1] + vd[1];
169			pp[2] = pictview.vp[2] + vd[2];
170	greg	1.21	viewloc(ip, &pictview, pp);
171			if (ip[2] <= FTINY \|\| ip[0] < 0. \|\| ip[0] >= 1. \|\|
172			ip[1] < 0. \|\| ip[1] >= 1.)
173	greg	1.1	return(-1.0);
174	greg	1.21	colr_color(res, getpictscan((int)(ip[1]pysiz))[(int)(ip[0]pxsiz)]);
175	greg	1.1	return(luminance(res)/exposure);
176			}
177
178
179			double
180	greg	1.14	getviewpix(vh, vv) /* compute single view pixel */
181	greg	1.1	int vh, vv;
182			{
183			FVECT dir;
184	greg	1.19	float rt_buf[12];
185	greg	1.1	double res;
186
187	greg	1.14	if (compdir(dir, vh, vv) < 0)
188	greg	1.1	return(-1.0);
189	greg	1.7	npixinvw++;
190	greg	1.1	if ((res = pict_val(dir)) >= 0.0)
191			return(res);
192	schorsch	2.7	if (rt_pd.r == -1) {
193	greg	1.7	npixmiss++;
194	greg	1.1	return(-1.0);
195	greg	1.7	}
196	greg	1.1	rt_buf[0] = ourview.vp[0];
197			rt_buf[1] = ourview.vp[1];
198			rt_buf[2] = ourview.vp[2];
199			rt_buf[3] = dir[0];
200			rt_buf[4] = dir[1];
201			rt_buf[5] = dir[2];
202			rt_compute(rt_buf, 1);
203			return(luminance(rt_buf));
204			}
205
206
207			getviewspan(vv, vb) /* compute a span of view pixels */
208			int vv;
209			float *vb;
210			{
211			float rt_buf[6MAXPIX]; / rtrace send/receive buffer */
212	greg	1.3	register int n; /* number of pixels in buffer */
213	greg	1.1	short buf_vh[MAXPIX]; /* pixel positions */
214			FVECT dir;
215			register int vh;
216
217	greg	1.4	#ifdef DEBUG
218	greg	1.1	if (verbose)
219			fprintf(stderr, "%s: computing view span at %d...\n",
220			progname, vv);
221	greg	1.4	#endif
222	greg	1.3	n = 0;
223	greg	1.1	for (vh = -hsize; vh <= hsize; vh++) {
224	greg	1.14	if (compdir(dir, vh, vv) < 0) { /* not in view */
225	greg	1.1	vb[vh+hsize] = -1.0;
226			continue;
227			}
228	greg	1.7	npixinvw++;
229	greg	1.1	if ((vb[vh+hsize] = pict_val(dir)) >= 0.0)
230			continue;
231	schorsch	2.7	if (rt_pd.r == -1) { /* missing information */
232	greg	1.7	npixmiss++;
233	greg	1.1	continue;
234	greg	1.7	}
235	greg	1.1	/* send to rtrace */
236	greg	1.19	if (n >= maxpix) { /* flush */
237	greg	1.3	rt_compute(rt_buf, n);
238			while (n-- > 0)
239			vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n);
240	greg	1.1	}
241	greg	1.3	rt_buf[6*n] = ourview.vp[0];
242			rt_buf[6*n+1] = ourview.vp[1];
243			rt_buf[6*n+2] = ourview.vp[2];
244			rt_buf[6*n+3] = dir[0];
245			rt_buf[6*n+4] = dir[1];
246			rt_buf[6*n+5] = dir[2];
247			buf_vh[n++] = vh;
248	greg	1.1	}
249	greg	1.4	#ifdef DEBUG
250	greg	1.2	if (verbose)
251			pict_stats();
252	greg	1.4	#endif
253	greg	1.3	if (n > 0) { /* process pending buffer */
254			rt_compute(rt_buf, n);
255			while (n-- > 0)
256			vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n);
257			}
258	greg	1.1	}
259
260
261			rt_compute(pb, np) /* process buffer through rtrace */
262			float *pb;
263			int np;
264			{
265	greg	1.4	#ifdef DEBUG
266	greg	1.1	if (verbose && np > 1)
267			fprintf(stderr, "%s: sending %d samples to rtrace...\n",
268			progname, np);
269	greg	1.4	#endif
270	schorsch	2.9	memset(pb+6np, '\0', 6sizeof(float));
271	schorsch	2.7	if (process(&rt_pd, (char )pb, (char )pb, 3sizeof(float)(np+1),
272	gregl	2.4	6sizeof(float)(np+1)) < 3sizeof(float)(np+1)) {
273	greg	1.19	fprintf(stderr, "%s: rtrace communication error\n",
274	greg	1.1	progname);
275			exit(1);
276			}
277			}
278
279
280	gwlarson	2.5	int
281	greg	1.1	getexpos(s) /* get exposure from header line */
282			char *s;
283			{
284	greg	1.13	char fmt[32];
285
286	greg	1.1	if (isexpos(s))
287			exposure *= exposval(s);
288	greg	1.13	else if (isformat(s)) {
289			formatval(fmt, s);
290			wrongformat = strcmp(fmt, COLRFMT);
291			}
292	gwlarson	2.5	return(0);
293	greg	1.1	}
294
295
296			open_pict(fn) /* open picture file */
297			char *fn;
298			{
299			if ((pictfp = fopen(fn, "r")) == NULL) {
300	greg	2.3	fprintf(stderr, "%s: cannot open\n", fn);
301	greg	1.1	exit(1);
302			}
303			exposure = 1.0;
304	greg	1.13	getheader(pictfp, getexpos, NULL);
305	greg	1.21	if (wrongformat \|\| !fscnresolu(&pxsiz, &pysiz, pictfp)) {
306			fprintf(stderr, "%s: incompatible picture format\n", fn);
307	greg	1.1	exit(1);
308			}
309	greg	1.8	initscans();
310	greg	1.1	}
311
312
313			close_pict() /* done with picture */
314			{
315			if (pictfp == NULL)
316			return;
317			fclose(pictfp);
318	greg	1.8	donescans();
319	greg	1.1	pictfp = NULL;
320			}
321
322
323			fork_rtrace(av) /* open pipe and start rtrace */
324			char *av[];
325			{
326	greg	1.19	int rval;
327	greg	1.1
328	schorsch	2.7	rval = open_process(&rt_pd, av);
329	greg	1.19	if (rval < 0) {
330	greg	1.1	perror(progname);
331			exit(1);
332			}
333	greg	1.19	if (rval == 0) {
334			fprintf(stderr, "%s: command not found\n", av[0]);
335	greg	1.1	exit(1);
336			}
337	greg	1.19	maxpix = rval/(6*sizeof(float));
338			if (maxpix > MAXPIX)
339			maxpix = MAXPIX;
340			maxpix--;
341	greg	1.1	}
342
343
344			done_rtrace() /* wait for rtrace to finish */
345			{
346	greg	1.19	int status;
347	greg	1.1
348	schorsch	2.7	status = close_process(&rt_pd);
349	greg	1.19	if (status > 0) {
350	greg	1.1	fprintf(stderr, "%s: bad status (%d) from rtrace\n",
351			progname, status);
352			exit(1);
353			}
354	schorsch	2.7	rt_pd.r = -1;
355	greg	1.8	}
356
357
358			SCAN *
359			scanretire() /* retire old scanlines to free list */
360			{
361			SCAN *sold[NRETIRE];
362			int n;
363			int h;
364			register SCAN *sl;
365			register int i;
366			/* grab the NRETIRE oldest scanlines */
367			sold[n = 0] = NULL;
368	greg	1.10	for (h = 0; h < HSIZE; h++)
369			for (sl = hashtab[h]; sl != NULL; sl = sl->next) {
370			for (i = n; i && sold[i-1]->lused > sl->lused; i--)
371			if (i < NRETIRE)
372	greg	1.8	sold[i] = sold[i-1];
373			if (i < NRETIRE) {
374	greg	1.10	sold[i] = sl;
375	greg	1.8	if (n < NRETIRE) /* grow list */
376			n++;
377	greg	1.10	}
378			}
379			/* put scanlines into free list */
380			for (i = 0; i < n; i++) {
381			h = shash(sold[i]->y);
382			sl = hashtab[h];
383			if (sl == sold[i])
384			hashtab[h] = sl->next;
385			else {
386			while (sl->next != sold[i]) /* IS in list */
387	greg	1.8	sl = sl->next;
388	greg	1.10	sl->next = sold[i]->next;
389	greg	1.8	}
390	greg	1.10	if (i > 0) { /* save oldest as return value */
391			sold[i]->next = freelist;
392			freelist = sold[i];
393			}
394	greg	1.8	}
395			return(sold[0]);
396			}
397
398
399			static char *scan_buf;
400
401
402			initscans() /* initialize scanline buffers */
403			{
404			int scansize;
405			register SCAN *ptr;
406			register int i;
407			/* initialize positions */
408	greg	2.2	scanpos = (long )bmalloc(pysizsizeof(long));
409	greg	1.8	if (scanpos == NULL)
410			memerr("scanline positions");
411			for (i = pysiz-1; i >= 0; i--)
412			scanpos[i] = -1L;
413			curpos = pysiz-1;
414			/* clear hash table */
415			for (i = 0; i < HSIZE; i++)
416			hashtab[i] = NULL;
417			/* allocate scanline buffers */
418			scansize = sizeof(SCAN) + pxsiz*sizeof(COLR);
419	greg	2.8	#ifdef ALIGNT
420			scansize = scansize+(sizeof(ALIGNT)-1) & ~(sizeof(ALIGNT)-1);
421	greg	1.8	#endif
422			i = MAXSBUF / scansize; /* compute number to allocate */
423			if (i > HSIZE)
424			i = HSIZE;
425	greg	2.2	scanbufsiz = i*scansize;
426			scan_buf = bmalloc(scanbufsiz); /* get in one big chunk */
427	greg	1.8	if (scan_buf == NULL)
428			memerr("scanline buffers");
429			ptr = (SCAN *)scan_buf;
430			freelist = NULL; /* build our free list */
431			while (i-- > 0) {
432			ptr->y = -1;
433			ptr->lused = -1;
434			ptr->next = freelist;
435			freelist = ptr;
436			ptr = (SCAN )((char )ptr + scansize); /* beware of C bugs */
437			}
438			}
439
440
441			donescans() /* free up scanlines */
442			{
443	greg	2.2	bfree(scan_buf, scanbufsiz);
444			bfree((char )scanpos, pysizsizeof(long));
445	greg	1.1	}