src/hd/rholo3.c

/* Copyright (c) 1998 Silicon Graphics, Inc. */

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

/*
 * Routines for tracking beam compuatations
 */

#include "rholo.h"
#include <sys/types.h>

#ifndef NFRAG2CHUNK
#define NFRAG2CHUNK     4096    /* number of fragments to start chunking */
#endif

#ifndef abs
#define abs(x)          ((x) > 0 ? (x) : -(x))
#endif
#ifndef sgn
#define sgn(x)          ((x) > 0 ? 1 : (x) < 0 ? -1 : 0)
#endif

#define rchunk(n)       (((n)+(RPACKSIZ/2))/RPACKSIZ)

extern time_t   time();

int     chunkycmp = 0;          /* clump beams together on disk */

static PACKHEAD *complist=NULL; /* list of beams to compute */
static int      complen=0;      /* length of complist */
static int      listpos=0;      /* current list position for next_packet */
static int      lastin= -1;     /* last ordered position in list */


int
beamcmp(b0, b1)                         /* comparison for compute order */
register PACKHEAD       *b0, *b1;
{
        BEAMI   *bip0, *bip1;
        register long   c;
                                        /* first check desired quantities */
        if (chunkycmp)
                c = rchunk(b1->nr)*(rchunk(b0->nc)+1L) -
                                rchunk(b0->nr)*(rchunk(b1->nc)+1L);
        else
                c = b1->nr*(b0->nc+1L) - b0->nr*(b1->nc+1L);
        if (c > 0) return(1);
        if (c < 0) return(-1);
                                /* only one file, so skip the following: */
#if 0
                                        /* next, check file descriptors */
        c = hdlist[b0->hd]->fd - hdlist[b1->hd]->fd;
        if (c) return(c);
#endif
                                        /* finally, check file positions */
        bip0 = &hdlist[b0->hd]->bi[b0->bi];
        bip1 = &hdlist[b1->hd]->bi[b1->bi];
                                        /* put diskless beams last */
        if (!bip0->nrd)
                return(bip1->nrd > 0);
        if (!bip1->nrd)
                return(-1);
        c = bip0->fo - bip1->fo;
        return(c < 0 ? -1 : c > 0);
}


int
beamidcmp(b0, b1)                       /* comparison for beam searching */
register PACKHEAD       *b0, *b1;
{
        register int    c = b0->hd - b1->hd;

        if (c) return(c);
        return(b0->bi - b1->bi);
}


int
dispbeam(b, hb)                         /* display a holodeck beam */
register BEAM   *b;
register HDBEAMI        *hb;
{
        static int      n = 0;
        static PACKHEAD *p = NULL;

        if (b == NULL)
                return;
        if (b->nrm > n) {               /* (re)allocate packet holder */
                n = b->nrm;
                if (p == NULL) p = (PACKHEAD *)malloc(packsiz(n));
                else p = (PACKHEAD *)realloc((char *)p, packsiz(n));
                if (p == NULL)
                        error(SYSTEM, "out of memory in dispbeam");
        }
                                        /* assign packet fields */
        bcopy((char *)hdbray(b), (char *)packra(p), b->nrm*sizeof(RAYVAL));
        p->nr = p->nc = b->nrm;
        for (p->hd = 0; hdlist[p->hd] != hb->h; p->hd++)
                if (hdlist[p->hd] == NULL)
                        error(CONSISTENCY, "unregistered holodeck in dispbeam");
        p->bi = hb->b;
        disp_packet(p);                 /* display it */
        if (n >= 1024) {                /* free ridiculous packets */
                free((char *)p);
                p = NULL; n = 0;
        }
}


bundle_set(op, clist, nents)    /* bundle set operation */
int     op;
PACKHEAD        *clist;
int     nents;
{
        int     oldnr, n;
        HDBEAMI *hbarr;
        register PACKHEAD       *csm;
        register int    i;
                                        /* search for common members */
        for (csm = clist+nents; csm-- > clist; )
                csm->nc = -1;
        qsort((char *)clist, nents, sizeof(PACKHEAD), beamidcmp);
        for (i = 0; i < complen; i++) {
                csm = (PACKHEAD *)bsearch((char *)(complist+i), (char *)clist,
                                nents, sizeof(PACKHEAD), beamidcmp);
                if (csm == NULL)
                        continue;
                oldnr = complist[i].nr;
                csm->nc = complist[i].nc;
                switch (op) {
                case BS_ADD:            /* add to count */
                        complist[i].nr += csm->nr;
                        csm->nr = 0;
                        break;
                case BS_ADJ:            /* reset count */
                        complist[i].nr = csm->nr;
                        csm->nr = 0;
                        break;
                case BS_DEL:            /* delete count */
                        if (csm->nr == 0 || csm->nr >= complist[i].nr)
                                complist[i].nr = 0;
                        else
                                complist[i].nr -= csm->nr;
                        break;
                }
                if (complist[i].nr != oldnr)
                        lastin = -1;    /* flag sort */
        }
                                /* record computed rays for uncommon beams */
        for (csm = clist+nents; csm-- > clist; )
                if (csm->nc < 0)
                        csm->nc = bnrays(hdlist[csm->hd], csm->bi);
                                /* complete list operations */
        switch (op) {
        case BS_NEW:                    /* new computation set */
                listpos = 0; lastin = -1;
                if (complen)            /* free old list */
                        free((char *)complist);
                complist = NULL;
                if (!(complen = nents))
                        return;
                complist = (PACKHEAD *)malloc(nents*sizeof(PACKHEAD));
                if (complist == NULL)
                        goto memerr;
                bcopy((char *)clist, (char *)complist, nents*sizeof(PACKHEAD));
                break;
        case BS_ADD:                    /* add to computation set */
        case BS_ADJ:                    /* adjust set quantities */
                if (nents <= 0)
                        return;
                sortcomplist();         /* sort updated list & new entries */
                qsort((char *)clist, nents, sizeof(PACKHEAD), beamcmp);
                                        /* what can't we satisfy? */
                for (i = nents, csm = clist; i-- && csm->nr > csm->nc; csm++)
                        ;
                n = csm - clist;
                if (op == BS_ADJ) {     /* don't regenerate adjusted beams */
                        for (++i; i-- && csm->nr > 0; csm++)
                                ;
                        nents = csm - clist;
                }
                if (n) {                /* allocate space for merged list */
                        PACKHEAD        *newlist;
                        newlist = (PACKHEAD *)malloc(
                                        (complen+n)*sizeof(PACKHEAD) );
                        if (newlist == NULL)
                                goto memerr;
                                                /* merge lists */
                        mergeclists(newlist, clist, n, complist, complen);
                        if (complen)
                                free((char *)complist);
                        complist = newlist;
                        complen += n;
                }
                listpos = 0;
                lastin = complen-1;     /* list is now sorted */
                break;
        case BS_DEL:                    /* delete from computation set */
                return;                 /* already done */
        default:
                error(CONSISTENCY, "bundle_set called with unknown operation");
        }
        if (outdev == NULL || !nents)   /* nothing to display? */
                return;
                                        /* load and display beams we have */
        hbarr = (HDBEAMI *)malloc(nents*sizeof(HDBEAMI));
        for (i = nents; i--; ) {
                hbarr[i].h = hdlist[clist[i].hd];
                hbarr[i].b = clist[i].bi;
        }
        hdloadbeams(hbarr, nents, dispbeam);
        free((char *)hbarr);
        if (hdfragflags&FF_READ) {
                listpos = 0;
                lastin = -1;            /* need to re-sort list */
        }
        return;
memerr:
        error(SYSTEM, "out of memory in bundle_set");
}


double
beamvolume(hp, bi)      /* compute approximate volume of a beam */
HOLO    *hp;
int     bi;
{
        GCOORD  gc[2];
        FVECT   cp[4], edgeA, edgeB, cent[2];
        FVECT   v, crossp[2], diffv;
        double  vol[2];
        register int    i;
                                        /* get grid coordinates */
        if (!hdbcoord(gc, hp, bi))
                error(CONSISTENCY, "bad beam index in beamvolume");
        for (i = 0; i < 2; i++) {       /* compute cell area vectors */
                hdcell(cp, hp, gc+i);
                VSUM(edgeA, cp[1], cp[0], -1.0);
                VSUM(edgeB, cp[3], cp[1], -1.0);
                fcross(crossp[i], edgeA, edgeB);
                                        /* compute center */
                cent[i][0] = 0.5*(cp[0][0] + cp[2][0]);
                cent[i][1] = 0.5*(cp[0][1] + cp[2][1]);
                cent[i][2] = 0.5*(cp[0][2] + cp[2][2]);
        }
                                        /* compute difference vector */
        VSUM(diffv, cent[1], cent[0], -1.0);
        for (i = 0; i < 2; i++) {       /* compute volume contributions */
                vol[i] = 0.5*DOT(crossp[i], diffv);
                if (vol[i] < 0.) vol[i] = -vol[i];
        }
        return(vol[0] + vol[1]);        /* return total volume */
}


init_global()                   /* initialize global ray computation */
{
        long    wtotal = 0;
        double  frac;
        int     i;
        register int    j, k;
                                        /* free old list and empty queue */
        if (complen > 0) {
                free((char *)complist);
                done_packets(flush_queue());
        }
                                        /* reseed random number generator */
        srandom(time(NULL));
                                        /* allocate beam list */
        complen = 0;
        for (j = 0; hdlist[j] != NULL; j++)
                complen += nbeams(hdlist[j]);
        complist = (PACKHEAD *)malloc(complen*sizeof(PACKHEAD));
        if (complist == NULL)
                error(SYSTEM, "out of memory in init_global");
                                        /* compute beam weights */
        k = 0;
        for (j = 0; hdlist[j] != NULL; j++) {
                frac = 512. * VLEN(hdlist[j]->wg[0]) *
                                VLEN(hdlist[j]->wg[1]) *
                                VLEN(hdlist[j]->wg[2]);
                for (i = nbeams(hdlist[j]); i > 0; i--) {
                        complist[k].hd = j;
                        complist[k].bi = i;
                        complist[k].nr = frac*beamvolume(hdlist[j], i) + 0.5;
                        complist[k].nc = bnrays(hdlist[j], i);
                        wtotal += complist[k++].nr;
                }
        }
                                        /* adjust weights */
        if (vdef(DISKSPACE))
                frac = 1024.*1024.*vflt(DISKSPACE) / (wtotal*sizeof(RAYVAL));
        else
                frac = 1024.*1024.*16384. / (wtotal*sizeof(RAYVAL));
        while (k--)
                complist[k].nr = frac*complist[k].nr + 0.5;
        listpos = 0; lastin = -1;       /* perform initial sort */
        sortcomplist();
                                        /* no view vicinity */
        myeye.rng = 0;
}


mergeclists(cdest, cl1, n1, cl2, n2)    /* merge two sorted lists */
register PACKHEAD       *cdest;
register PACKHEAD       *cl1, *cl2;
int     n1, n2;
{
        register int    cmp;

        while (n1 | n2) {
                if (!n1) cmp = 1;
                else if (!n2) cmp = -1;
                else cmp = beamcmp(cl1, cl2);
                if (cmp > 0) {
                        copystruct(cdest, cl2);
                        cl2++; n2--;
                } else {
                        copystruct(cdest, cl1);
                        cl1++; n1--;
                }
                cdest++;
        }
}


sortcomplist()                  /* fix our list order */
{
        PACKHEAD        *list2;
        int     listlen;
        register int    i;

        if (complen <= 0)       /* check to see if there is even a list */
                return;
        if (!chunkycmp)         /* check to see if fragment list is full */
                if (!hdfragOK(hdlist[0]->fd, &listlen, NULL)
#if NFRAG2CHUNK
                                || listlen >= NFRAG2CHUNK
#endif
                                ) {
                        chunkycmp++;    /* use "chunky" comparison */
                        lastin = -1;    /* need to re-sort list */
#ifdef DEBUG
                        error(WARNING, "using chunky comparison mode");
#endif
                }
        if (lastin < 0 || listpos*4 >= complen*3)
                qsort((char *)complist, complen, sizeof(PACKHEAD), beamcmp);
        else if (listpos) {     /* else sort and merge sublist */
                list2 = (PACKHEAD *)malloc(listpos*sizeof(PACKHEAD));
                if (list2 == NULL)
                        error(SYSTEM, "out of memory in sortcomplist");
                bcopy((char *)complist,(char *)list2,listpos*sizeof(PACKHEAD));
                qsort((char *)list2, listpos, sizeof(PACKHEAD), beamcmp);
                mergeclists(complist, list2, listpos,
                                complist+listpos, complen-listpos);
                free((char *)list2);
        }
                                        /* drop satisfied requests */
        for (i = complen; i-- && complist[i].nr <= complist[i].nc; )
                ;
        if (i < 0) {
                free((char *)complist);
                complist = NULL;
                complen = 0;
        } else if (i < complen-1) {
                list2 = (PACKHEAD *)realloc((char *)complist,
                                (i+1)*sizeof(PACKHEAD));
                if (list2 != NULL)
                        complist = list2;
                complen = i+1;
        }
        listpos = 0; lastin = i;
}


/*
 * The following routine works on the assumption that the bundle weights are
 * more or less evenly distributed, such that computing a packet causes
 * a given bundle to move way down in the computation order.  We keep
 * track of where the computed bundle with the highest priority would end
 * up, and if we get further in our compute list than this, we re-sort the
 * list and start again from the beginning.  Since
 * a merge sort is used, the sorting costs are minimal.
 */
next_packet(p, n)               /* prepare packet for computation */
register PACKET *p;
int     n;
{
        register int    i;

        if (listpos > lastin)           /* time to sort the list */
                sortcomplist();
        if (complen <= 0)
                return(0);
        p->hd = complist[listpos].hd;
        p->bi = complist[listpos].bi;
        p->nc = complist[listpos].nc;
        p->nr = complist[listpos].nr - p->nc;
        if (p->nr <= 0)
                return(0);
        DCHECK(n < 1 | n > RPACKSIZ,
                        CONSISTENCY, "next_packet called with bad n value");
        if (p->nr > n)
                p->nr = n;
        complist[listpos].nc += p->nr;  /* find where this one would go */
        if (hdgetbeam(hdlist[p->hd], p->bi) != NULL)
                hdfreefrag(hdlist[p->hd], p->bi);
        while (lastin > listpos && 
                        beamcmp(complist+lastin, complist+listpos) > 0)
                lastin--;
        listpos++;
        return(1);
}
Revision:	3.30
Committed:	Tue Feb 2 16:13:24 1999 UTC (25 years, 2 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 3.29:	+6 -10 lines
Log Message:	made chunkycmp global and added test for it in rholo()
#	User	Rev	Content
1	gwlarson	3.23	/* Copyright (c) 1998 Silicon Graphics, Inc. */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ SGI";
5			#endif
6
7	gregl	3.1	/*
8			* Routines for tracking beam compuatations
9			*/
10
11			#include "rholo.h"
12	gwlarson	3.28	#include <sys/types.h>
13	gregl	3.1
14	gwlarson	3.27	#ifndef NFRAG2CHUNK
15			#define NFRAG2CHUNK 4096 /* number of fragments to start chunking */
16			#endif
17
18			#ifndef abs
19	gregl	3.1	#define abs(x) ((x) > 0 ? (x) : -(x))
20	gwlarson	3.27	#endif
21			#ifndef sgn
22	gregl	3.1	#define sgn(x) ((x) > 0 ? 1 : (x) < 0 ? -1 : 0)
23	gwlarson	3.27	#endif
24	gregl	3.1
25	gwlarson	3.27	#define rchunk(n) (((n)+(RPACKSIZ/2))/RPACKSIZ)
26
27	gwlarson	3.28	extern time_t time();
28
29	gwlarson	3.30	int chunkycmp = 0; /* clump beams together on disk */
30
31	gregl	3.4	static PACKHEAD complist=NULL; / list of beams to compute */
32			static int complen=0; /* length of complist */
33			static int listpos=0; /* current list position for next_packet */
34			static int lastin= -1; /* last ordered position in list */
35	gregl	3.1
36
37			int
38	gwlarson	3.23	beamcmp(b0, b1) /* comparison for compute order */
39	gregl	3.2	register PACKHEAD b0, b1;
40			{
41	gwlarson	3.27	BEAMI bip0, bip1;
42			register long c;
43			/* first check desired quantities */
44	gwlarson	3.30	if (chunkycmp)
45	gwlarson	3.28	c = rchunk(b1->nr)*(rchunk(b0->nc)+1L) -
46			rchunk(b0->nr)*(rchunk(b1->nc)+1L);
47	gwlarson	3.27	else
48	gwlarson	3.28	c = b1->nr(b0->nc+1L) - b0->nr(b1->nc+1L);
49			if (c > 0) return(1);
50			if (c < 0) return(-1);
51	gwlarson	3.27	/* only one file, so skip the following: */
52			#if 0
53			/* next, check file descriptors */
54			c = hdlist[b0->hd]->fd - hdlist[b1->hd]->fd;
55			if (c) return(c);
56			#endif
57			/* finally, check file positions */
58			bip0 = &hdlist[b0->hd]->bi[b0->bi];
59			bip1 = &hdlist[b1->hd]->bi[b1->bi];
60			/* put diskless beams last */
61			if (!bip0->nrd)
62			return(bip1->nrd > 0);
63			if (!bip1->nrd)
64			return(-1);
65			c = bip0->fo - bip1->fo;
66			return(c < 0 ? -1 : c > 0);
67	gregl	3.2	}
68
69
70	gregl	3.14	int
71	gwlarson	3.23	beamidcmp(b0, b1) /* comparison for beam searching */
72			register PACKHEAD b0, b1;
73			{
74			register int c = b0->hd - b1->hd;
75
76			if (c) return(c);
77			return(b0->bi - b1->bi);
78			}
79
80
81			int
82			dispbeam(b, hb) /* display a holodeck beam */
83	gregl	3.14	register BEAM *b;
84	gwlarson	3.23	register HDBEAMI *hb;
85	gregl	3.14	{
86			static int n = 0;
87			static PACKHEAD *p = NULL;
88
89			if (b == NULL)
90			return;
91			if (b->nrm > n) { /* (re)allocate packet holder */
92			n = b->nrm;
93			if (p == NULL) p = (PACKHEAD *)malloc(packsiz(n));
94			else p = (PACKHEAD )realloc((char )p, packsiz(n));
95			if (p == NULL)
96			error(SYSTEM, "out of memory in dispbeam");
97			}
98			/* assign packet fields */
99			bcopy((char )hdbray(b), (char )packra(p), b->nrm*sizeof(RAYVAL));
100			p->nr = p->nc = b->nrm;
101	gwlarson	3.23	for (p->hd = 0; hdlist[p->hd] != hb->h; p->hd++)
102	gregl	3.14	if (hdlist[p->hd] == NULL)
103			error(CONSISTENCY, "unregistered holodeck in dispbeam");
104	gwlarson	3.23	p->bi = hb->b;
105	gregl	3.14	disp_packet(p); /* display it */
106	gwlarson	3.29	if (n >= 1024) { /* free ridiculous packets */
107			free((char *)p);
108			p = NULL; n = 0;
109			}
110	gregl	3.14	}
111
112
113	gregl	3.2	bundle_set(op, clist, nents) /* bundle set operation */
114			int op;
115	gwlarson	3.23	PACKHEAD *clist;
116	gregl	3.2	int nents;
117			{
118	gwlarson	3.23	int oldnr, n;
119			HDBEAMI *hbarr;
120			register PACKHEAD *csm;
121			register int i;
122			/* search for common members */
123			for (csm = clist+nents; csm-- > clist; )
124			csm->nc = -1;
125	gwlarson	3.25	qsort((char *)clist, nents, sizeof(PACKHEAD), beamidcmp);
126	gwlarson	3.23	for (i = 0; i < complen; i++) {
127			csm = (PACKHEAD )bsearch((char )(complist+i), (char *)clist,
128			nents, sizeof(PACKHEAD), beamidcmp);
129			if (csm == NULL)
130			continue;
131			oldnr = complist[i].nr;
132			csm->nc = complist[i].nc;
133			switch (op) {
134			case BS_ADD: /* add to count */
135			complist[i].nr += csm->nr;
136			csm->nr = 0;
137			break;
138			case BS_ADJ: /* reset count */
139			complist[i].nr = csm->nr;
140			csm->nr = 0;
141			break;
142			case BS_DEL: /* delete count */
143			if (csm->nr == 0 \|\| csm->nr >= complist[i].nr)
144			complist[i].nr = 0;
145			else
146			complist[i].nr -= csm->nr;
147			break;
148			}
149			if (complist[i].nr != oldnr)
150			lastin = -1; /* flag sort */
151	gregl	3.20	}
152	gwlarson	3.24	/* record computed rays for uncommon beams */
153	gwlarson	3.23	for (csm = clist+nents; csm-- > clist; )
154			if (csm->nc < 0)
155			csm->nc = bnrays(hdlist[csm->hd], csm->bi);
156	gregl	3.20	/* complete list operations */
157	gregl	3.2	switch (op) {
158			case BS_NEW: /* new computation set */
159	gwlarson	3.21	listpos = 0; lastin = -1;
160	gregl	3.20	if (complen) /* free old list */
161	gregl	3.2	free((char *)complist);
162	gregl	3.20	complist = NULL;
163			if (!(complen = nents))
164	gregl	3.2	return;
165			complist = (PACKHEAD )malloc(nentssizeof(PACKHEAD));
166			if (complist == NULL)
167			goto memerr;
168			bcopy((char )clist, (char )complist, nents*sizeof(PACKHEAD));
169			break;
170			case BS_ADD: /* add to computation set */
171	gregl	3.11	case BS_ADJ: /* adjust set quantities */
172	gregl	3.2	if (nents <= 0)
173			return;
174	gregl	3.20	sortcomplist(); /* sort updated list & new entries */
175	gregl	3.2	qsort((char *)clist, nents, sizeof(PACKHEAD), beamcmp);
176			/* what can't we satisfy? */
177	gwlarson	3.23	for (i = nents, csm = clist; i-- && csm->nr > csm->nc; csm++)
178	gregl	3.2	;
179	gwlarson	3.23	n = csm - clist;
180	gwlarson	3.22	if (op == BS_ADJ) { /* don't regenerate adjusted beams */
181	gwlarson	3.24	for (++i; i-- && csm->nr > 0; csm++)
182	gwlarson	3.22	;
183	gwlarson	3.24	nents = csm - clist;
184	gwlarson	3.22	}
185	gregl	3.2	if (n) { /* allocate space for merged list */
186			PACKHEAD *newlist;
187			newlist = (PACKHEAD *)malloc(
188			(complen+n)*sizeof(PACKHEAD) );
189			if (newlist == NULL)
190			goto memerr;
191			/* merge lists */
192			mergeclists(newlist, clist, n, complist, complen);
193			if (complen)
194			free((char *)complist);
195			complist = newlist;
196			complen += n;
197			}
198			listpos = 0;
199			lastin = complen-1; /* list is now sorted */
200			break;
201			case BS_DEL: /* delete from computation set */
202	gregl	3.20	return; /* already done */
203	gregl	3.2	default:
204			error(CONSISTENCY, "bundle_set called with unknown operation");
205			}
206	gwlarson	3.27	if (outdev == NULL \|\| !nents) /* nothing to display? */
207	gwlarson	3.22	return;
208			/* load and display beams we have */
209	gwlarson	3.23	hbarr = (HDBEAMI )malloc(nentssizeof(HDBEAMI));
210			for (i = nents; i--; ) {
211			hbarr[i].h = hdlist[clist[i].hd];
212			hbarr[i].b = clist[i].bi;
213	gregl	3.11	}
214	gwlarson	3.23	hdloadbeams(hbarr, nents, dispbeam);
215			free((char *)hbarr);
216	gwlarson	3.27	if (hdfragflags&FF_READ) {
217			listpos = 0;
218			lastin = -1; /* need to re-sort list */
219			}
220	gregl	3.2	return;
221			memerr:
222			error(SYSTEM, "out of memory in bundle_set");
223			}
224
225
226	gregl	3.13	double
227			beamvolume(hp, bi) /* compute approximate volume of a beam */
228	gregl	3.1	HOLO *hp;
229	gregl	3.13	int bi;
230	gregl	3.1	{
231	gregl	3.13	GCOORD gc[2];
232			FVECT cp[4], edgeA, edgeB, cent[2];
233			FVECT v, crossp[2], diffv;
234			double vol[2];
235			register int i;
236			/* get grid coordinates */
237			if (!hdbcoord(gc, hp, bi))
238			error(CONSISTENCY, "bad beam index in beamvolume");
239			for (i = 0; i < 2; i++) { /* compute cell area vectors */
240			hdcell(cp, hp, gc+i);
241			VSUM(edgeA, cp[1], cp[0], -1.0);
242			VSUM(edgeB, cp[3], cp[1], -1.0);
243			fcross(crossp[i], edgeA, edgeB);
244			/* compute center */
245			cent[i][0] = 0.5*(cp[0][0] + cp[2][0]);
246			cent[i][1] = 0.5*(cp[0][1] + cp[2][1]);
247			cent[i][2] = 0.5*(cp[0][2] + cp[2][2]);
248	gregl	3.1	}
249	gregl	3.13	/* compute difference vector */
250			VSUM(diffv, cent[1], cent[0], -1.0);
251			for (i = 0; i < 2; i++) { /* compute volume contributions */
252	gregl	3.15	vol[i] = 0.5*DOT(crossp[i], diffv);
253	gregl	3.13	if (vol[i] < 0.) vol[i] = -vol[i];
254			}
255			return(vol[0] + vol[1]); /* return total volume */
256	gregl	3.1	}
257
258
259			init_global() /* initialize global ray computation */
260			{
261			long wtotal = 0;
262			double frac;
263	gregl	3.13	int i;
264			register int j, k;
265	gregl	3.18	/* free old list and empty queue */
266			if (complen > 0) {
267	gregl	3.3	free((char *)complist);
268	gregl	3.18	done_packets(flush_queue());
269			}
270	gwlarson	3.28	/* reseed random number generator */
271			srandom(time(NULL));
272	gregl	3.1	/* allocate beam list */
273			complen = 0;
274			for (j = 0; hdlist[j] != NULL; j++)
275			complen += nbeams(hdlist[j]);
276			complist = (PACKHEAD )malloc(complensizeof(PACKHEAD));
277			if (complist == NULL)
278			error(SYSTEM, "out of memory in init_global");
279			/* compute beam weights */
280			k = 0;
281	gregl	3.13	for (j = 0; hdlist[j] != NULL; j++) {
282	gregl	3.19	frac = 512. * VLEN(hdlist[j]->wg[0]) *
283			VLEN(hdlist[j]->wg[1]) *
284			VLEN(hdlist[j]->wg[2]);
285	gregl	3.1	for (i = nbeams(hdlist[j]); i > 0; i--) {
286			complist[k].hd = j;
287			complist[k].bi = i;
288	gregl	3.13	complist[k].nr = frac*beamvolume(hdlist[j], i) + 0.5;
289	gregl	3.18	complist[k].nc = bnrays(hdlist[j], i);
290	gregl	3.1	wtotal += complist[k++].nr;
291			}
292	gregl	3.13	}
293	gregl	3.1	/* adjust weights */
294	gregl	3.12	if (vdef(DISKSPACE))
295	gregl	3.1	frac = 1024.1024.vflt(DISKSPACE) / (wtotal*sizeof(RAYVAL));
296	gregl	3.12	else
297			frac = 1024.1024.16384. / (wtotal*sizeof(RAYVAL));
298			while (k--)
299	gwlarson	3.24	complist[k].nr = frac*complist[k].nr + 0.5;
300	gwlarson	3.21	listpos = 0; lastin = -1; /* perform initial sort */
301			sortcomplist();
302	gwlarson	3.25	/* no view vicinity */
303			myeye.rng = 0;
304	gregl	3.1	}
305
306
307			mergeclists(cdest, cl1, n1, cl2, n2) /* merge two sorted lists */
308	gregl	3.16	register PACKHEAD *cdest;
309			register PACKHEAD cl1, cl2;
310	gregl	3.1	int n1, n2;
311			{
312	gregl	3.16	register int cmp;
313	gregl	3.1
314			while (n1 \| n2) {
315			if (!n1) cmp = 1;
316			else if (!n2) cmp = -1;
317			else cmp = beamcmp(cl1, cl2);
318			if (cmp > 0) {
319			copystruct(cdest, cl2);
320			cl2++; n2--;
321			} else {
322			copystruct(cdest, cl1);
323			cl1++; n1--;
324			}
325			cdest++;
326			}
327			}
328
329
330			sortcomplist() /* fix our list order */
331			{
332			PACKHEAD *list2;
333	gwlarson	3.27	int listlen;
334	gregl	3.2	register int i;
335
336	gregl	3.3	if (complen <= 0) /* check to see if there is even a list */
337	gregl	3.2	return;
338	gwlarson	3.30	if (!chunkycmp) /* check to see if fragment list is full */
339	gwlarson	3.27	if (!hdfragOK(hdlist[0]->fd, &listlen, NULL)
340			#if NFRAG2CHUNK
341			\|\| listlen >= NFRAG2CHUNK
342			#endif
343			) {
344	gwlarson	3.30	chunkycmp++; /* use "chunky" comparison */
345			lastin = -1; /* need to re-sort list */
346	gwlarson	3.27	#ifdef DEBUG
347			error(WARNING, "using chunky comparison mode");
348			#endif
349			}
350	gregl	3.6	if (lastin < 0 \|\| listpos4 >= complen3)
351	gregl	3.1	qsort((char *)complist, complen, sizeof(PACKHEAD), beamcmp);
352			else if (listpos) { /* else sort and merge sublist */
353			list2 = (PACKHEAD )malloc(listpossizeof(PACKHEAD));
354			if (list2 == NULL)
355			error(SYSTEM, "out of memory in sortcomplist");
356			bcopy((char )complist,(char )list2,listpos*sizeof(PACKHEAD));
357			qsort((char *)list2, listpos, sizeof(PACKHEAD), beamcmp);
358			mergeclists(complist, list2, listpos,
359			complist+listpos, complen-listpos);
360			free((char *)list2);
361			}
362	gregl	3.2	/* drop satisfied requests */
363	gregl	3.11	for (i = complen; i-- && complist[i].nr <= complist[i].nc; )
364	gregl	3.2	;
365	gregl	3.4	if (i < 0) {
366			free((char *)complist);
367			complist = NULL;
368			complen = 0;
369			} else if (i < complen-1) {
370	gregl	3.2	list2 = (PACKHEAD )realloc((char )complist,
371			(i+1)*sizeof(PACKHEAD));
372	gwlarson	3.26	if (list2 != NULL)
373	gregl	3.2	complist = list2;
374	gwlarson	3.26	complen = i+1;
375	gregl	3.2	}
376			listpos = 0; lastin = i;
377	gregl	3.1	}
378
379
380			/*
381			* The following routine works on the assumption that the bundle weights are
382			* more or less evenly distributed, such that computing a packet causes
383			* a given bundle to move way down in the computation order. We keep
384			* track of where the computed bundle with the highest priority would end
385	gwlarson	3.27	* up, and if we get further in our compute list than this, we re-sort the
386	gregl	3.11	* list and start again from the beginning. Since
387			* a merge sort is used, the sorting costs are minimal.
388	gregl	3.1	*/
389	gregl	3.17	next_packet(p, n) /* prepare packet for computation */
390	gregl	3.1	register PACKET *p;
391	gregl	3.17	int n;
392	gregl	3.1	{
393			register int i;
394
395	gregl	3.10	if (listpos > lastin) /* time to sort the list */
396			sortcomplist();
397	gregl	3.1	if (complen <= 0)
398			return(0);
399			p->hd = complist[listpos].hd;
400			p->bi = complist[listpos].bi;
401	gregl	3.11	p->nc = complist[listpos].nc;
402			p->nr = complist[listpos].nr - p->nc;
403	gregl	3.1	if (p->nr <= 0)
404			return(0);
405	gwlarson	3.28	DCHECK(n < 1 \| n > RPACKSIZ,
406			CONSISTENCY, "next_packet called with bad n value");
407	gregl	3.17	if (p->nr > n)
408			p->nr = n;
409	gregl	3.11	complist[listpos].nc += p->nr; /* find where this one would go */
410	gwlarson	3.27	if (hdgetbeam(hdlist[p->hd], p->bi) != NULL)
411			hdfreefrag(hdlist[p->hd], p->bi);
412	gregl	3.11	while (lastin > listpos &&
413			beamcmp(complist+lastin, complist+listpos) > 0)
414	gregl	3.1	lastin--;
415			listpos++;
416			return(1);
417			}