| 203 |
|
} |
| 204 |
|
|
| 205 |
|
|
| 206 |
– |
#define DCSCALE 11585.2 /* (1<<13)*sqrt(2) */ |
| 207 |
– |
#define FXNEG 01 |
| 208 |
– |
#define FYNEG 02 |
| 209 |
– |
#define FZNEG 04 |
| 210 |
– |
#define F1X 010 |
| 211 |
– |
#define F2Z 020 |
| 212 |
– |
#define F1SFT 5 |
| 213 |
– |
#define F2SFT 18 |
| 214 |
– |
#define FMASK 0x1fff |
| 215 |
– |
|
| 216 |
– |
static int4 |
| 217 |
– |
encodedir(dv) /* encode a normalized direction vector */ |
| 218 |
– |
FVECT dv; |
| 219 |
– |
{ |
| 220 |
– |
register int4 dc = 0; |
| 221 |
– |
int cd[3], cm; |
| 222 |
– |
register int i; |
| 223 |
– |
|
| 224 |
– |
for (i = 0; i < 3; i++) |
| 225 |
– |
if (dv[i] < 0.) { |
| 226 |
– |
cd[i] = dv[i] * -DCSCALE; |
| 227 |
– |
dc |= 1<<i; |
| 228 |
– |
} else |
| 229 |
– |
cd[i] = dv[i] * DCSCALE; |
| 230 |
– |
if (cd[0] <= cd[1]) { |
| 231 |
– |
dc |= F1X | cd[0] << F1SFT; |
| 232 |
– |
cm = cd[1]; |
| 233 |
– |
} else { |
| 234 |
– |
dc |= cd[1] << F1SFT; |
| 235 |
– |
cm = cd[0]; |
| 236 |
– |
} |
| 237 |
– |
if (cd[2] <= cm) |
| 238 |
– |
dc |= F2Z | cd[2] << F2SFT; |
| 239 |
– |
else |
| 240 |
– |
dc |= cm << F2SFT; |
| 241 |
– |
return(dc); |
| 242 |
– |
} |
| 243 |
– |
|
| 244 |
– |
|
| 245 |
– |
static |
| 246 |
– |
decodedir(dv, dc) /* decode a normalized direction vector */ |
| 247 |
– |
register FVECT dv; /* returned */ |
| 248 |
– |
register int4 dc; |
| 249 |
– |
{ |
| 250 |
– |
double d1, d2, der; |
| 251 |
– |
|
| 252 |
– |
d1 = ((dc>>F1SFT & FMASK)+.5)/DCSCALE; |
| 253 |
– |
d2 = ((dc>>F2SFT & FMASK)+.5)/DCSCALE; |
| 254 |
– |
der = sqrt(1. - d1*d1 - d2*d2); |
| 255 |
– |
if (dc & F1X) { |
| 256 |
– |
dv[0] = d1; |
| 257 |
– |
if (dc & F2Z) { dv[1] = der; dv[2] = d2; } |
| 258 |
– |
else { dv[1] = d2; dv[2] = der; } |
| 259 |
– |
} else { |
| 260 |
– |
dv[1] = d1; |
| 261 |
– |
if (dc & F2Z) { dv[0] = der; dv[2] = d2; } |
| 262 |
– |
else { dv[0] = d2; dv[2] = der; } |
| 263 |
– |
} |
| 264 |
– |
if (dc & FXNEG) dv[0] = -dv[0]; |
| 265 |
– |
if (dc & FYNEG) dv[1] = -dv[1]; |
| 266 |
– |
if (dc & FZNEG) dv[2] = -dv[2]; |
| 267 |
– |
} |
| 268 |
– |
|
| 269 |
– |
|
| 270 |
– |
static double |
| 271 |
– |
dir2diff(dc1, dc2) /* relative radians^2 between directions */ |
| 272 |
– |
int4 dc1, dc2; |
| 273 |
– |
{ |
| 274 |
– |
FVECT v1, v2; |
| 275 |
– |
|
| 276 |
– |
decodedir(v1, dc1); |
| 277 |
– |
decodedir(v2, dc2); |
| 278 |
– |
|
| 279 |
– |
return(2. - 2.*DOT(v1,v2)); |
| 280 |
– |
} |
| 281 |
– |
|
| 282 |
– |
|
| 283 |
– |
static double |
| 284 |
– |
fdir2diff(dc1, v2) /* relative radians^2 between directions */ |
| 285 |
– |
int4 dc1; |
| 286 |
– |
register FVECT v2; |
| 287 |
– |
{ |
| 288 |
– |
FVECT v1; |
| 289 |
– |
|
| 290 |
– |
decodedir(v1, dc1); |
| 291 |
– |
|
| 292 |
– |
return(2. - 2.*DOT(v1,v2)); |
| 293 |
– |
} |
| 294 |
– |
|
| 295 |
– |
|
| 206 |
|
int |
| 207 |
|
qtFindLeaf(x, y) /* find closest leaf to (x,y) */ |
| 208 |
|
int x, y; |
