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 |
|
|