1 |
/* Copyright (c) 1997 Silicon Graphics, Inc. */ |
2 |
|
3 |
#ifndef lint |
4 |
static char SCCSid[] = "$SunId$ SGI"; |
5 |
#endif |
6 |
|
7 |
/* |
8 |
* Holodeck beam tracking for display process |
9 |
*/ |
10 |
|
11 |
#include "rholo.h" |
12 |
#include "rhdisp.h" |
13 |
#include "rhdriver.h" |
14 |
|
15 |
#ifndef MAXDIST |
16 |
#define MAXDIST 13 /* maximum distance outside section */ |
17 |
#endif |
18 |
|
19 |
extern GCOORD *getviewcells(); |
20 |
|
21 |
static VIEW dvw; /* current view corresponding to beam list */ |
22 |
|
23 |
typedef struct { |
24 |
int hd; /* holodeck section number (-1 if inactive) */ |
25 |
int i[3]; /* voxel index (may be outside section) */ |
26 |
} VOXL; /* a voxel */ |
27 |
|
28 |
static VOXL voxel[8] = { /* current voxel list */ |
29 |
{-1}, {-1}, {-1}, {-1}, |
30 |
{-1}, {-1}, {-1}, {-1} |
31 |
}; |
32 |
|
33 |
#define CBEAMBLK 1024 /* cbeam allocation block size */ |
34 |
|
35 |
static struct beamcomp { |
36 |
short wants; /* flags telling which voxels want us */ |
37 |
short hd; /* holodeck section number */ |
38 |
int bi; /* beam index */ |
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} *cbeam = NULL; /* current beam list */ |
40 |
|
41 |
static int ncbeams = 0; /* number of sorted beams in cbeam */ |
42 |
static int xcbeams = 0; /* extra (unregistered) beams past ncbeams */ |
43 |
static int maxcbeam = 0; /* size of cbeam array */ |
44 |
|
45 |
struct cellact { |
46 |
short vi; /* voxel index */ |
47 |
short add; /* zero means delete */ |
48 |
short rev; /* reverse ray direction? */ |
49 |
}; /* action for cell */ |
50 |
|
51 |
struct beamact { |
52 |
struct cellact ca; /* cell action */ |
53 |
GCOORD gc; /* grid coordinate */ |
54 |
}; /* beam origin and action */ |
55 |
|
56 |
|
57 |
int |
58 |
newcbeam() /* allocate new entry at end of cbeam array */ |
59 |
{ |
60 |
int i; |
61 |
|
62 |
if ((i = ncbeams + xcbeams++) >= maxcbeam) { /* grow array */ |
63 |
maxcbeam += CBEAMBLK; |
64 |
if (cbeam == NULL) |
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cbeam = (struct beamcomp *)malloc( |
66 |
maxcbeam*sizeof(struct beamcomp) ); |
67 |
else |
68 |
cbeam = (struct beamcomp *)realloc( (char *)cbeam, |
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maxcbeam*sizeof(struct beamcomp) ); |
70 |
if (cbeam == NULL) |
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error(SYSTEM, "out of memory in newcbeam"); |
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} |
73 |
return(i); |
74 |
} |
75 |
|
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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 struct beamcomp *cb1, *cb2; |
80 |
{ |
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register int c; |
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|
83 |
if ((c = cb1->bi - cb2->bi)) /* sort on beam index first */ |
84 |
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 struct beamcomp *cb1, *cb2; |
92 |
{ |
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register int c; |
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|
95 |
if (!cb1->wants) /* put orphans at the end, unsorted */ |
96 |
return(cb2->wants); |
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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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|
102 |
|
103 |
int |
104 |
findcbeam(hd, bi) /* find the specified beam in our sorted list */ |
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int hd, bi; |
106 |
{ |
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struct beamcomp cb; |
108 |
register struct beamcomp *p; |
109 |
|
110 |
if (ncbeams <= 0) |
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return(-1); |
112 |
cb.wants = 0; cb.hd = hd; cb.bi = bi; |
113 |
p = (struct beamcomp *)bsearch((char *)&cb, (char *)cbeam, ncbeams, |
114 |
sizeof(struct beamcomp), cbeamcmp); |
115 |
if (p == NULL) |
116 |
return(-1); |
117 |
return(p - cbeam); |
118 |
} |
119 |
|
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|
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int |
122 |
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); |
130 |
/* 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].wants = 0; cbeam[n].hd = hd; cbeam[n].bi = bi; |
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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(struct beamcomp), |
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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].wants) |
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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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cbeamadj(v, hr, vr) /* adjust our beam list */ |
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VIEW *v; |
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int hr, vr; |
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{ |
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register PACKHEAD *pa; |
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register int i; |
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int n; |
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/* first handle additions */ |
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pa = (PACKHEAD *)malloc(xcbeams*sizeof(PACKHEAD)); |
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if (xcbeams && pa == NULL) |
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goto memerr; |
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for (i = xcbeams; i--; ) { |
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pa[i].hd = cbeam[ncbeams+i].hd; |
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pa[i].bi = cbeam[ncbeams+i].bi; |
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pa[i].nr = npixels(v, hr, vr, hdlist[pa[i].hd], pa[i].bi) + 1; |
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} |
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n = xcbeams; /* now sort list for deletions */ |
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cbeamsort(0); |
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pa = (PACKHEAD *)realloc((char *)pa, (n+xcbeams)*sizeof(PACKHEAD)); |
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if (n+xcbeams && pa == NULL) |
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goto memerr; |
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for (i = xcbeams; i--; ) { |
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pa[n+i].hd = cbeam[ncbeams+i].hd; |
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pa[n+i].bi = cbeam[ncbeams+i].bi; |
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pa[n+i].nr = 0; |
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} |
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n += xcbeams; |
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xcbeams = 0; /* delete orphans */ |
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serv_request(DR_ADJSET, n*sizeof(PACKHEAD), (char *)pa); |
194 |
free((char *)pa); |
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return; |
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memerr: |
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error(SYSTEM, "out of memory in cbeamadj"); |
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} |
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|
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|
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cbeamop(op, bl, n, v, hr, vr) /* update beams on server list */ |
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int op; |
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register struct beamcomp *bl; |
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int n; |
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VIEW *v; |
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int hr, vr; |
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{ |
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register PACKHEAD *pa; |
209 |
register int i; |
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|
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if (n <= 0) |
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return; |
213 |
pa = (PACKHEAD *)malloc(n*sizeof(PACKHEAD)); |
214 |
if (pa == NULL) |
215 |
error(SYSTEM, "out of memory in cbeamadd"); |
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for (i = 0; i < n; i++) { |
217 |
pa[i].hd = bl[i].hd; |
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pa[i].bi = bl[i].bi; |
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pa[i].nr = v==NULL ? 0 : |
220 |
npixels(v, hr, vr, hdlist[bl[i].hd], bl[i].bi); |
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} |
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serv_request(op, n*sizeof(PACKHEAD), (char *)pa); |
223 |
free((char *)pa); |
224 |
} |
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|
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|
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int |
228 |
set_voxels(vl, n) /* set new voxel array */ |
229 |
VOXL vl[8]; |
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int n; |
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{ |
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short wmap[256]; |
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int vmap[8]; |
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int comn = 0; |
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int no; |
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register int i, j; |
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/* find common voxels */ |
238 |
for (j = 0; j < 8 && voxel[j].hd >= 0; j++) { |
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vmap[j] = -1; |
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for (i = n; i--; ) |
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if (!bcmp((char *)(vl+i), (char *)(voxel+j), |
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sizeof(VOXL))) { |
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vmap[j] = i; |
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comn |= 1<<i; |
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break; |
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} |
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} |
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no = comn ? j : 0; /* compute flag mapping */ |
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for (i = 256; i--; ) { |
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wmap[i] = 0; |
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for (j = no; j--; ) |
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if (vmap[j] >= 0 && i & 1<<j) |
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wmap[i] |= 1<<vmap[j]; |
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} |
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/* fix cbeam flags */ |
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for (i = ncbeams; i--; ) |
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cbeam[i].wants = wmap[cbeam[i].wants]; |
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/* update our voxel list */ |
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bcopy((char *)vl, (char *)voxel, n*sizeof(VOXL)); |
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for (j = n; j < 8; j++) |
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voxel[j].hd = -1; |
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return(comn); /* return bit array of common voxels */ |
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} |
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|
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|
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int |
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get_voxels(vl, vp) /* find voxels corresponding to view point */ |
268 |
VOXL vl[8]; |
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FVECT vp; |
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{ |
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static int lastn = 0, lastd = -1; |
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int n = 0; |
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FVECT gp; |
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double d; |
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int dist, bestd = 0x7fff; |
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VOXL vox; |
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register int i, j, k; |
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/* find closest voxels */ |
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for (i = 0; n < 8 && hdlist[i]; i++) { |
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hdgrid(gp, hdlist[i], vp); |
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for (j = 0; n < 8 && j < 8; j++) { |
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dist = 0; |
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for (k = 0; k < 3; k++) { |
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d = gp[k] - .5 + (j>>k & 1); |
285 |
if (d < 0.) |
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dist += -(vox.i[k] = (int)d - 1); |
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else if ((vox.i[k] = d) >= hdlist[i]->grid[k]) |
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dist += vox.i[k] - |
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hdlist[i]->grid[k] + 1; |
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} |
291 |
if (dist > bestd) /* others were closer */ |
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continue; |
293 |
if (dist < bestd) { /* start closer list */ |
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n = 0; |
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bestd = dist; |
296 |
} |
297 |
vox.hd = i; /* add this voxel */ |
298 |
copystruct(&vl[n], &vox); |
299 |
n++; |
300 |
} |
301 |
} |
302 |
/* check for really stupid move */ |
303 |
if (bestd > MAXDIST) { |
304 |
error(COMMAND, "move past outer limits"); |
305 |
return(0); |
306 |
} |
307 |
/* warn of dangerous moves */ |
308 |
if (n < lastn && bestd >= lastd) |
309 |
error(WARNING, "moving outside holodeck section"); |
310 |
else if (n > lastn && bestd <= lastd) |
311 |
error(WARNING, "moving inside holodeck section"); |
312 |
lastd = bestd; |
313 |
return(lastn = n); |
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} |
315 |
|
316 |
|
317 |
int |
318 |
dobeam(gcp, bp) /* express interest or disintrest in a beam */ |
319 |
GCOORD *gcp; |
320 |
register struct beamact *bp; |
321 |
{ |
322 |
GCOORD gc[2]; |
323 |
int bi, i; |
324 |
/* compute beam index */ |
325 |
if (bp->ca.rev) { |
326 |
copystruct(gc, &bp->gc); |
327 |
copystruct(gc+1, gcp); |
328 |
} else { |
329 |
copystruct(gc, gcp); |
330 |
copystruct(gc+1, &bp->gc); |
331 |
} |
332 |
if ((bi = hdbindex(hdlist[voxel[bp->ca.vi].hd], gc)) <= 0) |
333 |
error(CONSISTENCY, "bad grid coordinate in dobeam"); |
334 |
if (bp->ca.add) { /* add it in */ |
335 |
i = getcbeam(voxel[bp->ca.vi].hd, bi); |
336 |
cbeam[i].wants |= 1<<bp->ca.vi; /* say we want it */ |
337 |
return(i == ncbeams+xcbeams-1); /* return 1 if totally new */ |
338 |
} |
339 |
/* else delete it */ |
340 |
i = findcbeam(voxel[bp->ca.vi].hd, bi); |
341 |
if (i >= 0 && cbeam[i].wants & 1<<bp->ca.vi) { |
342 |
cbeam[i].wants &= ~(1<<bp->ca.vi); /* we don't want it */ |
343 |
return(1); /* indicate change */ |
344 |
} |
345 |
return(0); |
346 |
} |
347 |
|
348 |
|
349 |
|
350 |
int |
351 |
docell(gcp, cap) /* find beams corresponding to cell and voxel */ |
352 |
GCOORD *gcp; |
353 |
register struct cellact *cap; |
354 |
{ |
355 |
register HOLO *hp = hdlist[voxel[cap->vi].hd]; |
356 |
FVECT org, dir[4]; |
357 |
FVECT vgp, cgp, vc; |
358 |
FVECT v1, v2; |
359 |
struct beamact bo; |
360 |
int axmax, j; |
361 |
double d, avmax; |
362 |
register int i; |
363 |
/* compute cell center */ |
364 |
cgp[gcp->w>>1] = gcp->w&1 ? hp->grid[gcp->w>>1] : 0 ; |
365 |
cgp[((gcp->w>>1)+1)%3] = gcp->i[0] + .5; |
366 |
cgp[((gcp->w>>1)+2)%3] = gcp->i[1] + .5; |
367 |
hdworld(org, hp, cgp); |
368 |
/* compute direction to voxel center */ |
369 |
for (i = 3; i--; ) |
370 |
vgp[i] = voxel[cap->vi].i[i] + .5; |
371 |
hdworld(vc, hp, vgp); |
372 |
for (i = 3; i--; ) |
373 |
vc[i] -= org[i]; |
374 |
/* compute maximum area axis */ |
375 |
axmax = -1; avmax = 0; |
376 |
for (i = 3; i--; ) { |
377 |
d = vgp[i] - cgp[i]; |
378 |
if (d < 0.) d = -d; |
379 |
if (d > avmax) { |
380 |
avmax = d; |
381 |
axmax = i; |
382 |
} |
383 |
} |
384 |
#ifdef DEBUG |
385 |
if (axmax < 0.) |
386 |
error(CONSISTENCY, "botched axis computation in docell"); |
387 |
#endif |
388 |
/* compute offset vectors */ |
389 |
d = 0.5/hp->grid[j=(axmax+1)%3]; |
390 |
for (i = 3; i--; ) |
391 |
v1[i] = hp->xv[j][i] * d; |
392 |
d = 0.5/hp->grid[j=(axmax+2)%3]; |
393 |
if (DOT(hp->wn[axmax], vc) < 0.) |
394 |
d = -d; /* reverse vertex ordering */ |
395 |
for (i = 3; i--; ) |
396 |
v2[i] = hp->xv[j][i] * d; |
397 |
/* compute voxel pyramid */ |
398 |
for (i = 3; i--; ) { |
399 |
dir[0][i] = vc[i] - v1[i] - v2[i]; |
400 |
dir[1][i] = vc[i] + v1[i] - v2[i]; |
401 |
dir[2][i] = vc[i] + v1[i] + v2[i]; |
402 |
dir[3][i] = vc[i] - v1[i] + v2[i]; |
403 |
} |
404 |
/* visit beams for opposite cells */ |
405 |
copystruct(&bo.ca, cap); |
406 |
copystruct(&bo.gc, gcp); |
407 |
return(visit_cells(org, dir, hp, dobeam, &bo)); |
408 |
} |
409 |
|
410 |
|
411 |
int |
412 |
doview(cap, vp) /* visit cells for a given view */ |
413 |
struct cellact *cap; |
414 |
VIEW *vp; |
415 |
{ |
416 |
int orient; |
417 |
FVECT org, dir[4]; |
418 |
/* compute view pyramid */ |
419 |
orient = viewpyramid(org, dir, hdlist[voxel[cap->vi].hd], vp); |
420 |
if (!orient) |
421 |
error(INTERNAL, "unusable view in doview"); |
422 |
cap->rev = orient < 0; |
423 |
/* visit cells within pyramid */ |
424 |
return(visit_cells(org, dir, hdlist[voxel[cap->vi].hd], docell, cap)); |
425 |
} |
426 |
|
427 |
|
428 |
mvview(voxi, vold, vnew) /* move view for a voxel */ |
429 |
int voxi; |
430 |
VIEW *vold, *vnew; |
431 |
{ |
432 |
int netchange = 0; |
433 |
struct cellact oca, nca; |
434 |
int ocnt, ncnt; |
435 |
int c; |
436 |
GCOORD *ogcl, *ngcl; |
437 |
register GCOORD *ogcp, *ngcp; |
438 |
/* get old and new cell lists */ |
439 |
ogcp = ogcl = getviewcells(&ocnt, hdlist[voxel[voxi].hd], vold); |
440 |
ngcp = ngcl = getviewcells(&ncnt, hdlist[voxel[voxi].hd], vnew); |
441 |
/* set up actions */ |
442 |
oca.vi = nca.vi = voxi; |
443 |
oca.add = 0; nca.add = 1; |
444 |
if ((oca.rev = ocnt < 0)) |
445 |
ocnt = -ocnt; |
446 |
if ((nca.rev = ncnt < 0)) |
447 |
ncnt = -ncnt; |
448 |
if (nca.rev == oca.rev) /* add and delete cells in order */ |
449 |
while (ocnt > 0 & ncnt > 0) |
450 |
if ((c = cellcmp(ogcp, ngcp)) > 0) { /* new cell */ |
451 |
netchange += docell(ngcp++, &nca); |
452 |
ncnt--; |
453 |
} else if (c < 0) { /* old cell */ |
454 |
netchange -= docell(ogcp++, &oca); |
455 |
ocnt--; |
456 |
} else { /* same cell */ |
457 |
ogcp++; ocnt--; |
458 |
ngcp++; ncnt--; |
459 |
} |
460 |
/* take care of list tails */ |
461 |
for ( ; ncnt > 0; ncnt--) |
462 |
netchange += docell(ngcp++, &nca); |
463 |
for ( ; ocnt > 0; ocnt--) |
464 |
netchange -= docell(ogcp++, &oca); |
465 |
/* clean up */ |
466 |
if (ogcl != NULL) free((char *)ogcl); |
467 |
if (ngcl != NULL) free((char *)ngcl); |
468 |
return(netchange); |
469 |
} |
470 |
|
471 |
|
472 |
int |
473 |
beam_sync() /* synchronize beams on server */ |
474 |
{ |
475 |
cbeamop(DR_NEWSET, cbeam, ncbeams, &odev.v, odev.hres, odev.vres); |
476 |
return(ncbeams); |
477 |
} |
478 |
|
479 |
|
480 |
beam_view(vn) /* change beam view (if advisable) */ |
481 |
VIEW *vn; |
482 |
{ |
483 |
struct cellact ca; |
484 |
VOXL vlnew[8]; |
485 |
int n, comn; |
486 |
|
487 |
if (vn == NULL || !vn->type) { /* clear our beam list */ |
488 |
set_voxels(vlnew, 0); |
489 |
cbeamop(DR_DELSET, cbeam, ncbeams, NULL, 0, 0); |
490 |
ncbeams = 0; |
491 |
dvw.type = 0; |
492 |
return(1); |
493 |
} |
494 |
/* find our new voxels */ |
495 |
n = get_voxels(vlnew, vn->vp); |
496 |
if (dvw.type && !n) { |
497 |
copystruct(vn, &dvw); /* cancel move */ |
498 |
return(0); |
499 |
} |
500 |
/* set the new voxels */ |
501 |
comn = set_voxels(vlnew, n); |
502 |
if (!dvw.type) |
503 |
comn = 0; |
504 |
ca.add = 1; /* update our beam list */ |
505 |
for (ca.vi = n; ca.vi--; ) |
506 |
if (comn & 1<<ca.vi) /* change which cells we see */ |
507 |
mvview(ca.vi, &dvw, vn); |
508 |
else /* else add all new cells */ |
509 |
doview(&ca, vn); |
510 |
#if 1 |
511 |
cbeamadj(vn, odev.hres, odev.vres); |
512 |
#else |
513 |
/* inform server of new beams */ |
514 |
cbeamop(DR_ADDSET, cbeam+ncbeams, xcbeams, vn, odev.hres, odev.vres); |
515 |
/* sort list to put orphans at end */ |
516 |
cbeamsort(0); |
517 |
/* tell server to delete orphans */ |
518 |
cbeamop(DR_DELSET, cbeam+ncbeams, xcbeams, NULL, 0, 0); |
519 |
xcbeams = 0; /* truncate our list */ |
520 |
#endif |
521 |
copystruct(&dvw, vn); /* record new view */ |
522 |
return(1); |
523 |
} |