| 15 |
|
|
| 16 |
|
VIEWPOINT myeye; /* target view position */ |
| 17 |
|
|
| 18 |
+ |
struct gclim { |
| 19 |
+ |
HOLO *hp; /* holodeck pointer */ |
| 20 |
+ |
GCOORD gc; /* grid cell */ |
| 21 |
+ |
FVECT egp; /* eye grid point */ |
| 22 |
+ |
double erg2; /* mean square eye grid range */ |
| 23 |
+ |
double gmin[2], gmax[2]; /* grid coordinate limits */ |
| 24 |
+ |
}; /* a grid coordinate range */ |
| 25 |
|
|
| 26 |
+ |
|
| 27 |
+ |
static |
| 28 |
+ |
initeyelim(gcl, hp, gc) /* initialize grid coordinate limits */ |
| 29 |
+ |
register struct gclim *gcl; |
| 30 |
+ |
register HOLO *hp; |
| 31 |
+ |
GCOORD *gc; |
| 32 |
+ |
{ |
| 33 |
+ |
register FLOAT *v; |
| 34 |
+ |
register int i; |
| 35 |
+ |
|
| 36 |
+ |
if (hp != NULL) { |
| 37 |
+ |
hdgrid(gcl->egp, gcl->hp = hp, myeye.vpt); |
| 38 |
+ |
gcl->erg2 = 0; |
| 39 |
+ |
for (i = 0, v = hp->wg[0]; i < 3; i++, v += 3) |
| 40 |
+ |
gcl->erg2 += DOT(v,v); |
| 41 |
+ |
gcl->erg2 *= (1./3.) * myeye.rng*myeye.rng; |
| 42 |
+ |
} |
| 43 |
+ |
if (gc != NULL) |
| 44 |
+ |
copystruct(&gcl->gc, gc); |
| 45 |
+ |
gcl->gmin[0] = gcl->gmin[1] = FHUGE; |
| 46 |
+ |
gcl->gmax[0] = gcl->gmax[1] = -FHUGE; |
| 47 |
+ |
} |
| 48 |
+ |
|
| 49 |
+ |
|
| 50 |
+ |
static |
| 51 |
+ |
groweyelim(gcl, gc, r0, r1, tight) /* grow grid limits about eye point */ |
| 52 |
+ |
register struct gclim *gcl; |
| 53 |
+ |
GCOORD *gc; |
| 54 |
+ |
double r0, r1; |
| 55 |
+ |
int tight; |
| 56 |
+ |
{ |
| 57 |
+ |
FVECT gp, ab; |
| 58 |
+ |
double ab2, od, cfact; |
| 59 |
+ |
double sqcoef[3], ctcoef[3], licoef[3], cnst; |
| 60 |
+ |
int gw, gi[2]; |
| 61 |
+ |
double wallpos, a, b, c, d, e, f; |
| 62 |
+ |
double root[2], yex; |
| 63 |
+ |
int n, i, j, nex; |
| 64 |
+ |
/* point/view cone */ |
| 65 |
+ |
i = gc->w>>1; |
| 66 |
+ |
gp[i] = gc->w&1 ? gcl->hp->grid[i] : 0; |
| 67 |
+ |
gp[hdwg0[gc->w]] = gc->i[0] + r0; |
| 68 |
+ |
gp[hdwg1[gc->w]] = gc->i[1] + r1; |
| 69 |
+ |
VSUB(ab, gcl->egp, gp); |
| 70 |
+ |
ab2 = DOT(ab, ab); |
| 71 |
+ |
gw = gcl->gc.w>>1; |
| 72 |
+ |
if ((i==gw ? ab[gw]*ab[gw] : ab2) <= gcl->erg2 + FTINY) { |
| 73 |
+ |
gcl->gmin[0] = gcl->gmin[1] = -FHUGE; |
| 74 |
+ |
gcl->gmax[0] = gcl->gmax[1] = FHUGE; |
| 75 |
+ |
return; /* too close (to wall) */ |
| 76 |
+ |
} |
| 77 |
+ |
ab2 = 1./ab2; /* 1/norm2(ab) */ |
| 78 |
+ |
od = DOT(gp, ab); /* origin dot direction */ |
| 79 |
+ |
cfact = 1./(1. - ab2*gcl->erg2); /* tan^2 + 1 of cone angle */ |
| 80 |
+ |
for (i = 0; i < 3; i++) { /* compute cone equation */ |
| 81 |
+ |
sqcoef[i] = ab[i]*ab[i]*cfact*ab2 - 1.; |
| 82 |
+ |
ctcoef[i] = 2.*ab[i]*ab[(i+1)%3]*cfact*ab2; |
| 83 |
+ |
licoef[i] = 2.*(gp[i] - ab[i]*cfact*od*ab2); |
| 84 |
+ |
} |
| 85 |
+ |
cnst = cfact*od*od*ab2 - DOT(gp,gp); |
| 86 |
+ |
/* |
| 87 |
+ |
* CONE: sqcoef[0]*x*x + sqcoef[1]*y*y + sqcoef[2]*z*z |
| 88 |
+ |
* + ctcoef[0]*x*y + ctcoef[1]*y*z + ctcoef[2]*z*x |
| 89 |
+ |
* + licoef[0]*x + licoef[1]*y + licoef[2]*z + cnst == 0 |
| 90 |
+ |
*/ |
| 91 |
+ |
/* equation for conic section in plane */ |
| 92 |
+ |
gi[0] = hdwg0[gcl->gc.w]; |
| 93 |
+ |
gi[1] = hdwg1[gcl->gc.w]; |
| 94 |
+ |
wallpos = gcl->gc.w&1 ? gcl->hp->grid[gw] : 0; |
| 95 |
+ |
a = sqcoef[gi[0]]; /* x2 */ |
| 96 |
+ |
b = ctcoef[gi[0]]; /* xy */ |
| 97 |
+ |
c = sqcoef[gi[1]]; /* y2 */ |
| 98 |
+ |
d = ctcoef[gw]*wallpos + licoef[gi[0]]; /* x */ |
| 99 |
+ |
e = ctcoef[gi[1]]*wallpos + licoef[gi[1]]; /* y */ |
| 100 |
+ |
f = wallpos*(wallpos*sqcoef[gw] + licoef[gw]) + cnst; |
| 101 |
+ |
for (i = 0; i < 2; i++) { |
| 102 |
+ |
if (i) { /* swap x and y coefficients */ |
| 103 |
+ |
register double t; |
| 104 |
+ |
t = a; a = c; c = t; |
| 105 |
+ |
t = d; d = e; e = t; |
| 106 |
+ |
} |
| 107 |
+ |
nex = 0; /* check global extrema */ |
| 108 |
+ |
n = quadratic(root, a*(4.*a*c-b*b), 2.*a*(2.*c*d-b*e), |
| 109 |
+ |
d*(c*d-b*e) + f*b*b); |
| 110 |
+ |
while (n-- > 0) { |
| 111 |
+ |
if (gc->w>>1 == gi[i] && |
| 112 |
+ |
(gc->w&1) ^ root[n] < gp[gc->w>>1]) { |
| 113 |
+ |
if (gc->w&1) |
| 114 |
+ |
gcl->gmin[i] = -FHUGE; |
| 115 |
+ |
else |
| 116 |
+ |
gcl->gmax[i] = FHUGE; |
| 117 |
+ |
nex++; |
| 118 |
+ |
continue; /* hyperbolic */ |
| 119 |
+ |
} |
| 120 |
+ |
if (tight) { |
| 121 |
+ |
yex = (-2.*a*root[n] - d)/b; |
| 122 |
+ |
if (yex < gcl->gc.i[1-i] || |
| 123 |
+ |
yex > gcl->gc.i[1-i]+1) |
| 124 |
+ |
continue; /* outside cell */ |
| 125 |
+ |
} |
| 126 |
+ |
if (root[n] < gcl->gmin[i]) |
| 127 |
+ |
gcl->gmin[i] = root[n]; |
| 128 |
+ |
if (root[n] > gcl->gmax[i]) |
| 129 |
+ |
gcl->gmax[i] = root[n]; |
| 130 |
+ |
nex++; |
| 131 |
+ |
} |
| 132 |
+ |
/* check local extrema */ |
| 133 |
+ |
for (j = nex < 2 ? 2 : 0; j--; ) { |
| 134 |
+ |
yex = gcl->gc.i[1-i] + j; |
| 135 |
+ |
n = quadratic(root, a, b*yex+d, yex*(yex*c+e)+f); |
| 136 |
+ |
while (n-- > 0) { |
| 137 |
+ |
if (gc->w>>1 == gi[i] && |
| 138 |
+ |
(gc->w&1) ^ root[n] < gp[gc->w>>1]) |
| 139 |
+ |
continue; |
| 140 |
+ |
if (root[n] < gcl->gmin[i]) |
| 141 |
+ |
gcl->gmin[i] = root[n]; |
| 142 |
+ |
if (root[n] > gcl->gmax[i]) |
| 143 |
+ |
gcl->gmax[i] = root[n]; |
| 144 |
+ |
} |
| 145 |
+ |
} |
| 146 |
+ |
} |
| 147 |
+ |
} |
| 148 |
+ |
|
| 149 |
+ |
|
| 150 |
+ |
static int |
| 151 |
+ |
clipeyelim(rrng, gcl) /* clip eye limits to grid cell */ |
| 152 |
+ |
register short rrng[2][2]; |
| 153 |
+ |
register struct gclim *gcl; |
| 154 |
+ |
{ |
| 155 |
+ |
int incell = 1; |
| 156 |
+ |
register int i; |
| 157 |
+ |
|
| 158 |
+ |
for (i = 0; i < 2; i++) { |
| 159 |
+ |
if (gcl->gmin[i] < gcl->gc.i[i]) |
| 160 |
+ |
gcl->gmin[i] = gcl->gc.i[i]; |
| 161 |
+ |
if (gcl->gmax[i] > gcl->gc.i[i]+1) |
| 162 |
+ |
gcl->gmax[i] = gcl->gc.i[i]+1; |
| 163 |
+ |
if (gcl->gmax[i] > gcl->gmin[i]) { |
| 164 |
+ |
rrng[i][0] = 256.*(gcl->gmin[i] - gcl->gc.i[i]) + |
| 165 |
+ |
(1.-FTINY); |
| 166 |
+ |
rrng[i][1] = 256.*(gcl->gmax[i] - gcl->gc.i[i]) + |
| 167 |
+ |
(1.-FTINY) - rrng[i][0]; |
| 168 |
+ |
} else |
| 169 |
+ |
rrng[i][0] = rrng[i][1] = 0; |
| 170 |
+ |
incell &= rrng[i][1] > 0; |
| 171 |
+ |
} |
| 172 |
+ |
return(incell); |
| 173 |
+ |
} |
| 174 |
+ |
|
| 175 |
+ |
|
| 176 |
|
packrays(rod, p) /* pack ray origins and directions */ |
| 177 |
|
register float *rod; |
| 178 |
|
register PACKET *p; |
| 179 |
|
{ |
| 180 |
< |
short packord[RPACKSIZ]; |
| 181 |
< |
float packdc[RPACKSIZ]; |
| 182 |
< |
int iterleft = 3*p->nr; |
| 183 |
< |
BYTE rpos[2][2]; |
| 184 |
< |
FVECT ro, rd, rp1; |
| 180 |
> |
#if 0 |
| 181 |
> |
double dist2sum = 0.; |
| 182 |
> |
FVECT vt; |
| 183 |
> |
#endif |
| 184 |
> |
int nretries = p->nr + 2; |
| 185 |
> |
struct gclim eyelim; |
| 186 |
> |
short rrng0[2][2], rrng1[2][2]; |
| 187 |
> |
int useyelim; |
| 188 |
|
GCOORD gc[2]; |
| 189 |
< |
double d, dc, meandist; |
| 190 |
< |
int i; |
| 191 |
< |
register int ii; |
| 189 |
> |
FVECT ro, rd; |
| 190 |
> |
double d; |
| 191 |
> |
register int i; |
| 192 |
|
|
| 193 |
|
if (!hdbcoord(gc, hdlist[p->hd], p->bi)) |
| 194 |
|
error(CONSISTENCY, "bad beam index in packrays"); |
| 195 |
< |
for (i = 0, meandist = 0.; i < p->nr || meandist > myeye.rng+FTINY; ) { |
| 196 |
< |
rpos[0][0] = frandom() * 256.; |
| 197 |
< |
rpos[0][1] = frandom() * 256.; |
| 198 |
< |
rpos[1][0] = frandom() * 256.; |
| 199 |
< |
rpos[1][1] = frandom() * 256.; |
| 200 |
< |
d = hdray(ro, rd, hdlist[p->hd], gc, rpos); |
| 201 |
< |
if (myeye.rng > FTINY) { /* check eyepoint */ |
| 202 |
< |
register int nexti; |
| 203 |
< |
|
| 204 |
< |
VSUM(rp1, ro, rd, d); |
| 205 |
< |
dc = sqrt(dist2line(myeye.vpt, ro, rp1)) / p->nr; |
| 206 |
< |
if (i == p->nr) { /* packet full */ |
| 207 |
< |
nexti = packord[i-1]; |
| 208 |
< |
if (!iterleft--) |
| 209 |
< |
break; /* tried enough! */ |
| 210 |
< |
if (dc >= packdc[nexti]) |
| 211 |
< |
continue; /* worse than worst */ |
| 212 |
< |
meandist -= packdc[nexti]; |
| 213 |
< |
} else |
| 214 |
< |
nexti = i++; |
| 215 |
< |
meandist += packdc[nexti] = dc; /* new distance */ |
| 216 |
< |
for (ii = i; --ii; ) { /* insertion sort */ |
| 217 |
< |
if (dc > packdc[packord[ii-1]]) |
| 218 |
< |
break; |
| 219 |
< |
packord[ii] = packord[ii-1]; |
| 195 |
> |
if ((useyelim = myeye.rng > FTINY)) { |
| 196 |
> |
initeyelim(&eyelim, hdlist[p->hd], gc); |
| 197 |
> |
groweyelim(&eyelim, gc+1, 0., 0., 0); |
| 198 |
> |
groweyelim(&eyelim, gc+1, 1., 1., 0); |
| 199 |
> |
useyelim = clipeyelim(rrng0, &eyelim); |
| 200 |
> |
#ifdef DEBUG |
| 201 |
> |
if (!useyelim) |
| 202 |
> |
error(WARNING, "no eye overlap in packrays"); |
| 203 |
> |
#endif |
| 204 |
> |
} |
| 205 |
> |
for (i = 0; i < p->nr; i++) { |
| 206 |
> |
retry: |
| 207 |
> |
if (useyelim) { |
| 208 |
> |
initeyelim(&eyelim, NULL, gc+1); |
| 209 |
> |
p->ra[i].r[0][0] = (int)(frandom()*rrng0[0][1]) |
| 210 |
> |
+ rrng0[0][0]; |
| 211 |
> |
p->ra[i].r[0][1] = (int)(frandom()*rrng0[1][1]) |
| 212 |
> |
+ rrng0[1][0]; |
| 213 |
> |
groweyelim(&eyelim, gc, |
| 214 |
> |
(1./256.)*(p->ra[i].r[0][0]+.5), |
| 215 |
> |
(1./256.)*(p->ra[i].r[0][1]+.5), 1); |
| 216 |
> |
if (!clipeyelim(rrng1, &eyelim)) { |
| 217 |
> |
useyelim = nretries-- > 0; |
| 218 |
> |
#ifdef DEBUG |
| 219 |
> |
if (!useyelim) |
| 220 |
> |
error(WARNING, |
| 221 |
> |
"exceeded retry limit in packrays"); |
| 222 |
> |
#endif |
| 223 |
> |
goto retry; |
| 224 |
|
} |
| 225 |
< |
packord[ii] = nexti; |
| 226 |
< |
ii = nexti; /* put it here */ |
| 227 |
< |
} else |
| 228 |
< |
ii = i++; |
| 225 |
> |
p->ra[i].r[1][0] = (int)(frandom()*rrng1[0][1]) |
| 226 |
> |
+ rrng1[0][0]; |
| 227 |
> |
p->ra[i].r[1][1] = (int)(frandom()*rrng1[1][1]) |
| 228 |
> |
+ rrng1[1][0]; |
| 229 |
> |
} else { |
| 230 |
> |
p->ra[i].r[0][0] = frandom() * 256.; |
| 231 |
> |
p->ra[i].r[0][1] = frandom() * 256.; |
| 232 |
> |
p->ra[i].r[1][0] = frandom() * 256.; |
| 233 |
> |
p->ra[i].r[1][1] = frandom() * 256.; |
| 234 |
> |
} |
| 235 |
> |
d = hdray(ro, rd, hdlist[p->hd], gc, p->ra[i].r); |
| 236 |
> |
#if 0 |
| 237 |
> |
VSUM(vt, ro, rd, d); |
| 238 |
> |
dist2sum += dist2line(myeye.vpt, ro, vt); |
| 239 |
> |
#endif |
| 240 |
|
if (p->offset != NULL) { |
| 241 |
|
if (!vdef(OBSTRUCTIONS)) |
| 242 |
|
d *= frandom(); /* random offset */ |
| 243 |
|
VSUM(ro, ro, rd, d); /* advance ray */ |
| 244 |
< |
p->offset[ii] = d; |
| 244 |
> |
p->offset[i] = d; |
| 245 |
|
} |
| 246 |
< |
p->ra[ii].r[0][0] = rpos[0][0]; |
| 247 |
< |
p->ra[ii].r[0][1] = rpos[0][1]; |
| 248 |
< |
p->ra[ii].r[1][0] = rpos[1][0]; |
| 249 |
< |
p->ra[ii].r[1][1] = rpos[1][1]; |
| 75 |
< |
VCOPY(rod+6*ii, ro); |
| 76 |
< |
VCOPY(rod+6*ii+3, rd); |
| 246 |
> |
VCOPY(rod, ro); |
| 247 |
> |
rod += 3; |
| 248 |
> |
VCOPY(rod, rd); |
| 249 |
> |
rod += 3; |
| 250 |
|
} |
| 251 |
< |
#ifdef DEBUG |
| 252 |
< |
fprintf(stderr, "%f mean distance for target %f (%d iterations)\n", |
| 253 |
< |
meandist, myeye.rng, 3*p->nr - iterleft); |
| 251 |
> |
#if 0 |
| 252 |
> |
fprintf(stderr, "%f RMS (%d retries)\t", sqrt(dist2sum/p->nr), |
| 253 |
> |
p->nr + 2 - nretries); |
| 254 |
|
#endif |
| 255 |
|
} |
| 256 |
|
|
