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/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ SGI"; |
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#endif |
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|
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/* |
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* Holodeck beam tracking for display process |
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*/ |
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|
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#include "rholo.h" |
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#include "rhdisp.h" |
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#include "rhdriver.h" |
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|
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#ifndef MEYERNG |
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#define MEYERNG 0.2 /* target mean eye range (rel. to grid) */ |
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#endif |
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|
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#define CBEAMBLK 1024 /* cbeam allocation block size */ |
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|
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static PACKHEAD *cbeam = NULL; /* current beam list */ |
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static int ncbeams = 0; /* number of sorted beams in cbeam */ |
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static int xcbeams = 0; /* extra (unregistered) beams past ncbeams */ |
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static int maxcbeam = 0; /* size of cbeam array */ |
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|
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VIEWPOINT cureye; /* current eye position */ |
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|
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|
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int |
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newcbeam() /* allocate new entry at end of cbeam array */ |
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{ |
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int i; |
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|
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if ((i = ncbeams + xcbeams++) >= maxcbeam) { /* grow array */ |
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maxcbeam += CBEAMBLK; |
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if (cbeam == NULL) |
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cbeam = (PACKHEAD *)malloc( |
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maxcbeam*sizeof(PACKHEAD) ); |
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else |
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cbeam = (PACKHEAD *)realloc( (char *)cbeam, |
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maxcbeam*sizeof(PACKHEAD) ); |
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if (cbeam == NULL) |
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error(SYSTEM, "out of memory in newcbeam"); |
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} |
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return(i); |
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} |
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|
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|
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int |
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cbeamcmp(cb1, cb2) /* compare two cbeam entries for sort: keep orphans */ |
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register PACKHEAD *cb1, *cb2; |
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{ |
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register int c; |
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|
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if ((c = cb1->bi - cb2->bi)) /* sort on beam index first */ |
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return(c); |
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return(cb1->hd - cb2->hd); /* use hd to resolve matches */ |
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} |
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|
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|
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int |
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cbeamcmp2(cb1, cb2) /* compare two cbeam entries for sort: no orphans */ |
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register PACKHEAD *cb1, *cb2; |
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{ |
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register int c; |
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|
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if (!cb1->nr) /* put orphans at the end, unsorted */ |
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return(cb2->nr); |
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if (!cb2->nr) |
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return(-1); |
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if ((c = cb1->bi - cb2->bi)) /* sort on beam index first */ |
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return(c); |
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return(cb1->hd - cb2->hd); /* use hd to resolve matches */ |
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} |
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|
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|
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int |
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findcbeam(hd, bi) /* find the specified beam in our sorted list */ |
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int hd, bi; |
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{ |
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PACKHEAD cb; |
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register PACKHEAD *p; |
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|
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if (ncbeams <= 0) |
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return(-1); |
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cb.hd = hd; cb.bi = bi; cb.nr = cb.nc = 0; |
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p = (PACKHEAD *)bsearch((char *)&cb, (char *)cbeam, ncbeams, |
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sizeof(PACKHEAD), cbeamcmp); |
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if (p == NULL) |
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return(-1); |
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return(p - cbeam); |
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} |
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|
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|
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int |
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getcbeam(hd, bi) /* get the specified beam, allocating as necessary */ |
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register int hd; |
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int bi; |
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{ |
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register int n; |
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/* first, look in sorted list */ |
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if ((n = findcbeam(hd, bi)) >= 0) |
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return(n); |
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/* linear search through xcbeams to be sure */ |
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for (n = ncbeams+xcbeams; n-- > ncbeams; ) |
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if (cbeam[n].bi == bi && cbeam[n].hd == hd) |
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return(n); |
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/* check legality */ |
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if (hd < 0 | hd >= HDMAX || hdlist[hd] == NULL) |
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error(INTERNAL, "illegal holodeck number in getcbeam"); |
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if (bi < 1 | bi > nbeams(hdlist[hd])) |
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error(INTERNAL, "illegal beam index in getcbeam"); |
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n = newcbeam(); /* allocate and assign */ |
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cbeam[n].hd = hd; cbeam[n].bi = bi; cbeam[n].nr = cbeam[n].nc = 0; |
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return(n); |
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} |
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|
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|
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cbeamsort(adopt) /* sort our beam list, possibly turning out orphans */ |
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int adopt; |
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{ |
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register int i; |
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|
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if (!(ncbeams += xcbeams)) |
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return; |
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xcbeams = 0; |
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qsort((char *)cbeam, ncbeams, sizeof(PACKHEAD), |
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adopt ? cbeamcmp : cbeamcmp2); |
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if (adopt) |
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return; |
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for (i = ncbeams; i--; ) /* identify orphans */ |
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if (cbeam[i].nr) |
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break; |
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xcbeams = ncbeams - ++i; /* put orphans after ncbeams */ |
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ncbeams = i; |
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} |
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|
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|
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beam_init(fresh) /* clear beam list for new view(s) */ |
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int fresh; |
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{ |
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register int i; |
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|
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if (fresh) /* discard old beams? */ |
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ncbeams = xcbeams = 0; |
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else /* else clear sample requests */ |
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for (i = ncbeams+xcbeams; i--; ) |
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cbeam[i].nr = 0; |
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cureye.rng = 0.; |
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} |
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|
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|
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int2 * |
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beam_view(vn, hr, vr) /* add beam view (if advisable) */ |
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VIEW *vn; |
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int hr, vr; |
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{ |
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int2 *slist; |
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BEAMLIST blist; |
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double eravg, d; |
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register HOLO *hp; |
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register int i, n; |
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/* compute beams for view */ |
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slist = viewbeams(vn, hr, vr, &blist); |
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if (*slist < 0) { |
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error(COMMAND, "no sections visible from this view"); |
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return(NULL); |
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} |
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/* sort current beam list */ |
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cbeamsort(1); |
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/* add new beams to list */ |
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for (i = blist.nb; i--; ) { |
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n = getcbeam(blist.bl[i].hd, blist.bl[i].bi); |
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if (blist.bl[i].nr > cbeam[n].nr) |
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cbeam[n].nr = blist.bl[i].nr; |
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} |
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free((char *)blist.bl); /* free list */ |
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if (MEYERNG <= FTINY) |
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return(slist); |
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/* compute average eye range */ |
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eravg = 0.; |
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for (n = 0; slist[n] >= 0; n++) { |
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hp = hdlist[slist[n]]; |
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eravg += MEYERNG/3. / VLEN(hp->wg[0]) + |
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MEYERNG/3. / VLEN(hp->wg[1]) + |
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MEYERNG/3. / VLEN(hp->wg[2]) ; |
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} |
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eravg /= (double)n; |
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/* add to current eye position */ |
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if (cureye.rng <= FTINY) { |
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VCOPY(cureye.vpt, vn->vp); |
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cureye.rng = eravg; |
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} else if ((d = sqrt(dist2(vn->vp,cureye.vpt))) + eravg > cureye.rng) { |
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for (i = 3; i--; ) |
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cureye.vpt[i] = 0.5*(cureye.vpt[i] + vn->vp[i]); |
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cureye.rng = 0.5*(cureye.rng + eravg + d); |
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} |
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return(slist); |
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} |
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|
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|
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int |
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beam_sync(all) /* update beam list on server */ |
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int all; |
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{ |
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/* set new eye position */ |
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serv_request(DR_VIEWPOINT, sizeof(VIEWPOINT), (char *)&cureye); |
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/* sort list (put orphans at end) */ |
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cbeamsort(all < 0); |
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/* send beam request */ |
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if (all) { |
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if (ncbeams > 0) |
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serv_request(DR_NEWSET, |
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ncbeams*sizeof(PACKHEAD), cbeam); |
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} else { |
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if (ncbeams+xcbeams > 0) |
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serv_request(DR_ADJSET, |
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(ncbeams+xcbeams)*sizeof(PACKHEAD), cbeam); |
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} |
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xcbeams = 0; /* truncate our list */ |
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return(ncbeams); |
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} |
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|
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|
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gridlines(f) /* run through holodeck section grid lines */ |
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int (*f)(); |
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{ |
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register int hd, w, i; |
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int g0, g1; |
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FVECT wp[2], mov; |
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double d; |
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/* do each wall on each section */ |
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for (hd = 0; hdlist[hd] != NULL; hd++) |
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for (w = 0; w < 6; w++) { |
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g0 = hdwg0[w]; |
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g1 = hdwg1[w]; |
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d = 1.0/hdlist[hd]->grid[g0]; |
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mov[0] = d * hdlist[hd]->xv[g0][0]; |
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mov[1] = d * hdlist[hd]->xv[g0][1]; |
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mov[2] = d * hdlist[hd]->xv[g0][2]; |
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if (w & 1) { |
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VSUM(wp[0], hdlist[hd]->orig, |
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hdlist[hd]->xv[w>>1], 1.); |
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VSUM(wp[0], wp[0], mov, 1.); |
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} else |
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VCOPY(wp[0], hdlist[hd]->orig); |
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VSUM(wp[1], wp[0], hdlist[hd]->xv[g1], 1.); |
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for (i = hdlist[hd]->grid[g0]; ; ) { /* g0 lines */ |
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(*f)(wp); |
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if (!--i) break; |
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wp[0][0] += mov[0]; wp[0][1] += mov[1]; |
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wp[0][2] += mov[2]; wp[1][0] += mov[0]; |
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wp[1][1] += mov[1]; wp[1][2] += mov[2]; |
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} |
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d = 1.0/hdlist[hd]->grid[g1]; |
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mov[0] = d * hdlist[hd]->xv[g1][0]; |
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mov[1] = d * hdlist[hd]->xv[g1][1]; |
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mov[2] = d * hdlist[hd]->xv[g1][2]; |
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if (w & 1) |
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VSUM(wp[0], hdlist[hd]->orig, |
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hdlist[hd]->xv[w>>1], 1.); |
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else |
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VSUM(wp[0], hdlist[hd]->orig, mov, 1.); |
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VSUM(wp[1], wp[0], hdlist[hd]->xv[g0], 1.); |
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for (i = hdlist[hd]->grid[g1]; ; ) { /* g1 lines */ |
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(*f)(wp); |
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if (!--i) break; |
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wp[0][0] += mov[0]; wp[0][1] += mov[1]; |
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wp[0][2] += mov[2]; wp[1][0] += mov[0]; |
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wp[1][1] += mov[1]; wp[1][2] += mov[2]; |
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} |
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} |
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} |