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"

#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)

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 */
static int      chunky=0;       /* clump beams together on disk */


int
beamcmp(b0, b1)                         /* comparison for compute order */
register PACKHEAD       *b0, *b1;
{
        BEAMI   *bip0, *bip1;
        register long   c;
                                        /* first check desired quantities */
        if (chunky)
                c = rchunk(b1->nr)*(rchunk(b0->nc)+1) -
                                rchunk(b0->nr)*(rchunk(b1->nc)+1);
        else
                c = b1->nr*(b0->nc+1) - b0->nr*(b1->nc+1);
        if (c) return(c);
                                /* 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 */
}


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());
        }
                                        /* 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 (!chunky)            /* check to see if fragment list is full */
                if (!hdfragOK(hdlist[0]->fd, &listlen, NULL)
#if NFRAG2CHUNK
                                || listlen >= NFRAG2CHUNK
#endif
                                ) {
#ifdef DEBUG
                        error(WARNING, "using chunky comparison mode");
#endif
                        chunky++;       /* use "chunky" comparison */
                        lastin = -1;    /* need to re-sort list */
                }
        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);
#ifdef DEBUG
        if (n < 1 | n > RPACKSIZ)
                error(CONSISTENCY, "next_packet called with bad n value");
#endif
        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:	3.27
Committed:	Thu Jan 7 22:04:49 1999 UTC (25 years, 10 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 3.26:	+57 -3 lines
Log Message:	created hdfragflags variable for controlling fragment deallocation added "chunky" sorting mode to rholo to decrease file fragmentation problems
#	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
13	gwlarson	3.27	#ifndef NFRAG2CHUNK
14			#define NFRAG2CHUNK 4096 /* number of fragments to start chunking */
15			#endif
16
17			#ifndef abs
18	gregl	3.1	#define abs(x) ((x) > 0 ? (x) : -(x))
19	gwlarson	3.27	#endif
20			#ifndef sgn
21	gregl	3.1	#define sgn(x) ((x) > 0 ? 1 : (x) < 0 ? -1 : 0)
22	gwlarson	3.27	#endif
23	gregl	3.1
24	gwlarson	3.27	#define rchunk(n) (((n)+(RPACKSIZ/2))/RPACKSIZ)
25
26	gregl	3.4	static PACKHEAD complist=NULL; / list of beams to compute */
27			static int complen=0; /* length of complist */
28			static int listpos=0; /* current list position for next_packet */
29			static int lastin= -1; /* last ordered position in list */
30	gwlarson	3.27	static int chunky=0; /* clump beams together on disk */
31	gregl	3.1
32
33			int
34	gwlarson	3.23	beamcmp(b0, b1) /* comparison for compute order */
35	gregl	3.2	register PACKHEAD b0, b1;
36			{
37	gwlarson	3.27	BEAMI bip0, bip1;
38			register long c;
39			/* first check desired quantities */
40			if (chunky)
41			c = rchunk(b1->nr)*(rchunk(b0->nc)+1) -
42			rchunk(b0->nr)*(rchunk(b1->nc)+1);
43			else
44			c = b1->nr(b0->nc+1) - b0->nr(b1->nc+1);
45			if (c) return(c);
46			/* only one file, so skip the following: */
47			#if 0
48			/* next, check file descriptors */
49			c = hdlist[b0->hd]->fd - hdlist[b1->hd]->fd;
50			if (c) return(c);
51			#endif
52			/* finally, check file positions */
53			bip0 = &hdlist[b0->hd]->bi[b0->bi];
54			bip1 = &hdlist[b1->hd]->bi[b1->bi];
55			/* put diskless beams last */
56			if (!bip0->nrd)
57			return(bip1->nrd > 0);
58			if (!bip1->nrd)
59			return(-1);
60			c = bip0->fo - bip1->fo;
61			return(c < 0 ? -1 : c > 0);
62	gregl	3.2	}
63
64
65	gregl	3.14	int
66	gwlarson	3.23	beamidcmp(b0, b1) /* comparison for beam searching */
67			register PACKHEAD b0, b1;
68			{
69			register int c = b0->hd - b1->hd;
70
71			if (c) return(c);
72			return(b0->bi - b1->bi);
73			}
74
75
76			int
77			dispbeam(b, hb) /* display a holodeck beam */
78	gregl	3.14	register BEAM *b;
79	gwlarson	3.23	register HDBEAMI *hb;
80	gregl	3.14	{
81			static int n = 0;
82			static PACKHEAD *p = NULL;
83
84			if (b == NULL)
85			return;
86			if (b->nrm > n) { /* (re)allocate packet holder */
87			n = b->nrm;
88			if (p == NULL) p = (PACKHEAD *)malloc(packsiz(n));
89			else p = (PACKHEAD )realloc((char )p, packsiz(n));
90			if (p == NULL)
91			error(SYSTEM, "out of memory in dispbeam");
92			}
93			/* assign packet fields */
94			bcopy((char )hdbray(b), (char )packra(p), b->nrm*sizeof(RAYVAL));
95			p->nr = p->nc = b->nrm;
96	gwlarson	3.23	for (p->hd = 0; hdlist[p->hd] != hb->h; p->hd++)
97	gregl	3.14	if (hdlist[p->hd] == NULL)
98			error(CONSISTENCY, "unregistered holodeck in dispbeam");
99	gwlarson	3.23	p->bi = hb->b;
100	gregl	3.14	disp_packet(p); /* display it */
101			}
102
103
104	gregl	3.2	bundle_set(op, clist, nents) /* bundle set operation */
105			int op;
106	gwlarson	3.23	PACKHEAD *clist;
107	gregl	3.2	int nents;
108			{
109	gwlarson	3.23	int oldnr, n;
110			HDBEAMI *hbarr;
111			register PACKHEAD *csm;
112			register int i;
113			/* search for common members */
114			for (csm = clist+nents; csm-- > clist; )
115			csm->nc = -1;
116	gwlarson	3.25	qsort((char *)clist, nents, sizeof(PACKHEAD), beamidcmp);
117	gwlarson	3.23	for (i = 0; i < complen; i++) {
118			csm = (PACKHEAD )bsearch((char )(complist+i), (char *)clist,
119			nents, sizeof(PACKHEAD), beamidcmp);
120			if (csm == NULL)
121			continue;
122			oldnr = complist[i].nr;
123			csm->nc = complist[i].nc;
124			switch (op) {
125			case BS_ADD: /* add to count */
126			complist[i].nr += csm->nr;
127			csm->nr = 0;
128			break;
129			case BS_ADJ: /* reset count */
130			complist[i].nr = csm->nr;
131			csm->nr = 0;
132			break;
133			case BS_DEL: /* delete count */
134			if (csm->nr == 0 \|\| csm->nr >= complist[i].nr)
135			complist[i].nr = 0;
136			else
137			complist[i].nr -= csm->nr;
138			break;
139			}
140			if (complist[i].nr != oldnr)
141			lastin = -1; /* flag sort */
142	gregl	3.20	}
143	gwlarson	3.24	/* record computed rays for uncommon beams */
144	gwlarson	3.23	for (csm = clist+nents; csm-- > clist; )
145			if (csm->nc < 0)
146			csm->nc = bnrays(hdlist[csm->hd], csm->bi);
147	gregl	3.20	/* complete list operations */
148	gregl	3.2	switch (op) {
149			case BS_NEW: /* new computation set */
150	gwlarson	3.21	listpos = 0; lastin = -1;
151	gregl	3.20	if (complen) /* free old list */
152	gregl	3.2	free((char *)complist);
153	gregl	3.20	complist = NULL;
154			if (!(complen = nents))
155	gregl	3.2	return;
156			complist = (PACKHEAD )malloc(nentssizeof(PACKHEAD));
157			if (complist == NULL)
158			goto memerr;
159			bcopy((char )clist, (char )complist, nents*sizeof(PACKHEAD));
160			break;
161			case BS_ADD: /* add to computation set */
162	gregl	3.11	case BS_ADJ: /* adjust set quantities */
163	gregl	3.2	if (nents <= 0)
164			return;
165	gregl	3.20	sortcomplist(); /* sort updated list & new entries */
166	gregl	3.2	qsort((char *)clist, nents, sizeof(PACKHEAD), beamcmp);
167			/* what can't we satisfy? */
168	gwlarson	3.23	for (i = nents, csm = clist; i-- && csm->nr > csm->nc; csm++)
169	gregl	3.2	;
170	gwlarson	3.23	n = csm - clist;
171	gwlarson	3.22	if (op == BS_ADJ) { /* don't regenerate adjusted beams */
172	gwlarson	3.24	for (++i; i-- && csm->nr > 0; csm++)
173	gwlarson	3.22	;
174	gwlarson	3.24	nents = csm - clist;
175	gwlarson	3.22	}
176	gregl	3.2	if (n) { /* allocate space for merged list */
177			PACKHEAD *newlist;
178			newlist = (PACKHEAD *)malloc(
179			(complen+n)*sizeof(PACKHEAD) );
180			if (newlist == NULL)
181			goto memerr;
182			/* merge lists */
183			mergeclists(newlist, clist, n, complist, complen);
184			if (complen)
185			free((char *)complist);
186			complist = newlist;
187			complen += n;
188			}
189			listpos = 0;
190			lastin = complen-1; /* list is now sorted */
191			break;
192			case BS_DEL: /* delete from computation set */
193	gregl	3.20	return; /* already done */
194	gregl	3.2	default:
195			error(CONSISTENCY, "bundle_set called with unknown operation");
196			}
197	gwlarson	3.27	if (outdev == NULL \|\| !nents) /* nothing to display? */
198	gwlarson	3.22	return;
199			/* load and display beams we have */
200	gwlarson	3.23	hbarr = (HDBEAMI )malloc(nentssizeof(HDBEAMI));
201			for (i = nents; i--; ) {
202			hbarr[i].h = hdlist[clist[i].hd];
203			hbarr[i].b = clist[i].bi;
204	gregl	3.11	}
205	gwlarson	3.23	hdloadbeams(hbarr, nents, dispbeam);
206			free((char *)hbarr);
207	gwlarson	3.27	if (hdfragflags&FF_READ) {
208			listpos = 0;
209			lastin = -1; /* need to re-sort list */
210			}
211	gregl	3.2	return;
212			memerr:
213			error(SYSTEM, "out of memory in bundle_set");
214			}
215
216
217	gregl	3.13	double
218			beamvolume(hp, bi) /* compute approximate volume of a beam */
219	gregl	3.1	HOLO *hp;
220	gregl	3.13	int bi;
221	gregl	3.1	{
222	gregl	3.13	GCOORD gc[2];
223			FVECT cp[4], edgeA, edgeB, cent[2];
224			FVECT v, crossp[2], diffv;
225			double vol[2];
226			register int i;
227			/* get grid coordinates */
228			if (!hdbcoord(gc, hp, bi))
229			error(CONSISTENCY, "bad beam index in beamvolume");
230			for (i = 0; i < 2; i++) { /* compute cell area vectors */
231			hdcell(cp, hp, gc+i);
232			VSUM(edgeA, cp[1], cp[0], -1.0);
233			VSUM(edgeB, cp[3], cp[1], -1.0);
234			fcross(crossp[i], edgeA, edgeB);
235			/* compute center */
236			cent[i][0] = 0.5*(cp[0][0] + cp[2][0]);
237			cent[i][1] = 0.5*(cp[0][1] + cp[2][1]);
238			cent[i][2] = 0.5*(cp[0][2] + cp[2][2]);
239	gregl	3.1	}
240	gregl	3.13	/* compute difference vector */
241			VSUM(diffv, cent[1], cent[0], -1.0);
242			for (i = 0; i < 2; i++) { /* compute volume contributions */
243	gregl	3.15	vol[i] = 0.5*DOT(crossp[i], diffv);
244	gregl	3.13	if (vol[i] < 0.) vol[i] = -vol[i];
245			}
246			return(vol[0] + vol[1]); /* return total volume */
247	gregl	3.1	}
248
249
250			init_global() /* initialize global ray computation */
251			{
252			long wtotal = 0;
253			double frac;
254	gregl	3.13	int i;
255			register int j, k;
256	gregl	3.18	/* free old list and empty queue */
257			if (complen > 0) {
258	gregl	3.3	free((char *)complist);
259	gregl	3.18	done_packets(flush_queue());
260			}
261	gregl	3.1	/* allocate beam list */
262			complen = 0;
263			for (j = 0; hdlist[j] != NULL; j++)
264			complen += nbeams(hdlist[j]);
265			complist = (PACKHEAD )malloc(complensizeof(PACKHEAD));
266			if (complist == NULL)
267			error(SYSTEM, "out of memory in init_global");
268			/* compute beam weights */
269			k = 0;
270	gregl	3.13	for (j = 0; hdlist[j] != NULL; j++) {
271	gregl	3.19	frac = 512. * VLEN(hdlist[j]->wg[0]) *
272			VLEN(hdlist[j]->wg[1]) *
273			VLEN(hdlist[j]->wg[2]);
274	gregl	3.1	for (i = nbeams(hdlist[j]); i > 0; i--) {
275			complist[k].hd = j;
276			complist[k].bi = i;
277	gregl	3.13	complist[k].nr = frac*beamvolume(hdlist[j], i) + 0.5;
278	gregl	3.18	complist[k].nc = bnrays(hdlist[j], i);
279	gregl	3.1	wtotal += complist[k++].nr;
280			}
281	gregl	3.13	}
282	gregl	3.1	/* adjust weights */
283	gregl	3.12	if (vdef(DISKSPACE))
284	gregl	3.1	frac = 1024.1024.vflt(DISKSPACE) / (wtotal*sizeof(RAYVAL));
285	gregl	3.12	else
286			frac = 1024.1024.16384. / (wtotal*sizeof(RAYVAL));
287			while (k--)
288	gwlarson	3.24	complist[k].nr = frac*complist[k].nr + 0.5;
289	gwlarson	3.21	listpos = 0; lastin = -1; /* perform initial sort */
290			sortcomplist();
291	gwlarson	3.25	/* no view vicinity */
292			myeye.rng = 0;
293	gregl	3.1	}
294
295
296			mergeclists(cdest, cl1, n1, cl2, n2) /* merge two sorted lists */
297	gregl	3.16	register PACKHEAD *cdest;
298			register PACKHEAD cl1, cl2;
299	gregl	3.1	int n1, n2;
300			{
301	gregl	3.16	register int cmp;
302	gregl	3.1
303			while (n1 \| n2) {
304			if (!n1) cmp = 1;
305			else if (!n2) cmp = -1;
306			else cmp = beamcmp(cl1, cl2);
307			if (cmp > 0) {
308			copystruct(cdest, cl2);
309			cl2++; n2--;
310			} else {
311			copystruct(cdest, cl1);
312			cl1++; n1--;
313			}
314			cdest++;
315			}
316			}
317
318
319			sortcomplist() /* fix our list order */
320			{
321			PACKHEAD *list2;
322	gwlarson	3.27	int listlen;
323	gregl	3.2	register int i;
324
325	gregl	3.3	if (complen <= 0) /* check to see if there is even a list */
326	gregl	3.2	return;
327	gwlarson	3.27	if (!chunky) /* check to see if fragment list is full */
328			if (!hdfragOK(hdlist[0]->fd, &listlen, NULL)
329			#if NFRAG2CHUNK
330			\|\| listlen >= NFRAG2CHUNK
331			#endif
332			) {
333			#ifdef DEBUG
334			error(WARNING, "using chunky comparison mode");
335			#endif
336			chunky++; /* use "chunky" comparison */
337			lastin = -1; /* need to re-sort list */
338			}
339	gregl	3.6	if (lastin < 0 \|\| listpos4 >= complen3)
340	gregl	3.1	qsort((char *)complist, complen, sizeof(PACKHEAD), beamcmp);
341			else if (listpos) { /* else sort and merge sublist */
342			list2 = (PACKHEAD )malloc(listpossizeof(PACKHEAD));
343			if (list2 == NULL)
344			error(SYSTEM, "out of memory in sortcomplist");
345			bcopy((char )complist,(char )list2,listpos*sizeof(PACKHEAD));
346			qsort((char *)list2, listpos, sizeof(PACKHEAD), beamcmp);
347			mergeclists(complist, list2, listpos,
348			complist+listpos, complen-listpos);
349			free((char *)list2);
350			}
351	gregl	3.2	/* drop satisfied requests */
352	gregl	3.11	for (i = complen; i-- && complist[i].nr <= complist[i].nc; )
353	gregl	3.2	;
354	gregl	3.4	if (i < 0) {
355			free((char *)complist);
356			complist = NULL;
357			complen = 0;
358			} else if (i < complen-1) {
359	gregl	3.2	list2 = (PACKHEAD )realloc((char )complist,
360			(i+1)*sizeof(PACKHEAD));
361	gwlarson	3.26	if (list2 != NULL)
362	gregl	3.2	complist = list2;
363	gwlarson	3.26	complen = i+1;
364	gregl	3.2	}
365			listpos = 0; lastin = i;
366	gregl	3.1	}
367
368
369			/*
370			* The following routine works on the assumption that the bundle weights are
371			* more or less evenly distributed, such that computing a packet causes
372			* a given bundle to move way down in the computation order. We keep
373			* track of where the computed bundle with the highest priority would end
374	gwlarson	3.27	* up, and if we get further in our compute list than this, we re-sort the
375	gregl	3.11	* list and start again from the beginning. Since
376			* a merge sort is used, the sorting costs are minimal.
377	gregl	3.1	*/
378	gregl	3.17	next_packet(p, n) /* prepare packet for computation */
379	gregl	3.1	register PACKET *p;
380	gregl	3.17	int n;
381	gregl	3.1	{
382			register int i;
383
384	gregl	3.10	if (listpos > lastin) /* time to sort the list */
385			sortcomplist();
386	gregl	3.1	if (complen <= 0)
387			return(0);
388			p->hd = complist[listpos].hd;
389			p->bi = complist[listpos].bi;
390	gregl	3.11	p->nc = complist[listpos].nc;
391			p->nr = complist[listpos].nr - p->nc;
392	gregl	3.1	if (p->nr <= 0)
393			return(0);
394	gregl	3.17	#ifdef DEBUG
395			if (n < 1 \| n > RPACKSIZ)
396			error(CONSISTENCY, "next_packet called with bad n value");
397			#endif
398			if (p->nr > n)
399			p->nr = n;
400	gregl	3.11	complist[listpos].nc += p->nr; /* find where this one would go */
401	gwlarson	3.27	if (hdgetbeam(hdlist[p->hd], p->bi) != NULL)
402			hdfreefrag(hdlist[p->hd], p->bi);
403	gregl	3.11	while (lastin > listpos &&
404			beamcmp(complist+lastin, complist+listpos) > 0)
405	gregl	3.1	lastin--;
406			listpos++;
407			return(1);
408			}