| 1 |
/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
| 2 |
|
| 3 |
#ifndef lint |
| 4 |
static char SCCSid[] = "$SunId$ SGI"; |
| 5 |
#endif |
| 6 |
|
| 7 |
/* |
| 8 |
* Routines for drawing samples using depth buffer checks. |
| 9 |
*/ |
| 10 |
|
| 11 |
#include "standard.h" |
| 12 |
|
| 13 |
#include <sys/types.h> |
| 14 |
#include <GL/glx.h> |
| 15 |
#include <GL/glu.h> |
| 16 |
|
| 17 |
#include "random.h" |
| 18 |
#include "rhd_odraw.h" |
| 19 |
|
| 20 |
#ifndef DEPTHEPS |
| 21 |
#define DEPTHEPS 0.02 /* depth epsilon */ |
| 22 |
#endif |
| 23 |
#ifndef SAMPSPERBLOCK |
| 24 |
#define SAMPSPERBLOCK 1024 /* target samples per image block */ |
| 25 |
#endif |
| 26 |
#ifndef SFREEFRAC |
| 27 |
#define SFREEFRAC 0.2 /* fraction to free at a time */ |
| 28 |
#endif |
| 29 |
#ifndef MAXFAN |
| 30 |
#define MAXFAN 32 /* maximum arms in a triangle fan */ |
| 31 |
#endif |
| 32 |
#ifndef MINFAN |
| 33 |
#define MINFAN 4 /* minimum arms in a triangle fan */ |
| 34 |
#endif |
| 35 |
#ifndef FANSIZE |
| 36 |
#define FANSIZE 3.5 /* fan sizing factor */ |
| 37 |
#endif |
| 38 |
|
| 39 |
#define NEWMAP 01 /* need to recompute mapping */ |
| 40 |
#define NEWRGB 02 /* need to remap RGB values */ |
| 41 |
#define NEWHIST 04 /* clear histogram as well */ |
| 42 |
|
| 43 |
struct ODview *odView; /* our view list */ |
| 44 |
int odNViews; /* number of views in our list */ |
| 45 |
|
| 46 |
struct ODsamp odS; /* sample values */ |
| 47 |
|
| 48 |
static int needmapping; /* what needs doing with tone map */ |
| 49 |
|
| 50 |
|
| 51 |
#define SAMP32 (32*(2*sizeof(short)+sizeof(union ODfunion)+sizeof(TMbright)+\ |
| 52 |
6*sizeof(BYTE))+sizeof(int4)) |
| 53 |
|
| 54 |
int |
| 55 |
odInit(n) /* initialize drawing routines */ |
| 56 |
int n; |
| 57 |
{ |
| 58 |
int nbytes, i, j, k, nextsamp, count, blockdiv; |
| 59 |
int res[2]; |
| 60 |
|
| 61 |
if (odNViews > 0) { /* deallocate view structures */ |
| 62 |
for (i = odNViews; i--; ) { |
| 63 |
free((char *)odView[i].bmap); |
| 64 |
free((char *)odView[i].pmap); |
| 65 |
if (odView[i].emap != NULL) |
| 66 |
free((char *)odView[i].emap); |
| 67 |
} |
| 68 |
free((char *)odView); |
| 69 |
odView = NULL; |
| 70 |
odNViews = 0; |
| 71 |
} |
| 72 |
if (n && n != odS.nsamp) { |
| 73 |
/* round space up to nearest power of 2 */ |
| 74 |
nbytes = (n+31)/32 * SAMP32; |
| 75 |
for (i = 1024; nbytes > i-8; i <<= 1) |
| 76 |
; |
| 77 |
n = (i-8)/SAMP32 * 32; |
| 78 |
needmapping = NEWHIST; |
| 79 |
} |
| 80 |
if (n != odS.nsamp) { /* (re)allocate sample array */ |
| 81 |
if (odS.nsamp) |
| 82 |
free(odS.base); |
| 83 |
odS.nsamp = 0; |
| 84 |
if (!n) |
| 85 |
return(0); |
| 86 |
nbytes = (n+31)/32 * SAMP32; |
| 87 |
odS.base = (char *)malloc(nbytes); |
| 88 |
if (odS.base == NULL) |
| 89 |
return(0); |
| 90 |
/* assign larger alignment types earlier */ |
| 91 |
odS.f = (union ODfunion *)odS.base; |
| 92 |
odS.redraw = (int4 *)(odS.f + n); |
| 93 |
odS.ip = (short (*)[2])(odS.redraw + n/32); |
| 94 |
odS.brt = (TMbright *)(odS.ip + n); |
| 95 |
odS.chr = (BYTE (*)[3])(odS.brt + n); |
| 96 |
odS.rgb = (BYTE (*)[3])(odS.chr + n); |
| 97 |
odS.nsamp = n; |
| 98 |
} |
| 99 |
if (!n) |
| 100 |
return(0); |
| 101 |
/* allocate view information */ |
| 102 |
count = 0; /* count pixels */ |
| 103 |
for (i = 0; dev_auxview(i, res) != NULL; i++) |
| 104 |
count += res[0]*res[1]; |
| 105 |
odView = (struct ODview *)malloc(i*sizeof(struct ODview)); |
| 106 |
if (odView == NULL) |
| 107 |
return(0); |
| 108 |
odNViews = i; |
| 109 |
blockdiv = sqrt(count/(n/SAMPSPERBLOCK)) + 0.5; |
| 110 |
if (blockdiv < 8) blockdiv = 8; |
| 111 |
nextsamp = 0; count /= blockdiv*blockdiv; /* # blocks */ |
| 112 |
while (i--) { /* initialize each view */ |
| 113 |
dev_auxview(i, res); |
| 114 |
odView[i].hhi = res[0]; |
| 115 |
odView[i].hlow = (res[0] + blockdiv/2) / blockdiv; |
| 116 |
if (odView[i].hlow < 1) odView[i].hlow = 1; |
| 117 |
odView[i].vhi = res[1]; |
| 118 |
odView[i].vlow = (res[1] + blockdiv/2) / blockdiv; |
| 119 |
if (odView[i].vlow < 1) odView[i].vlow = 1; |
| 120 |
odView[i].emap = NULL; |
| 121 |
odView[i].dmap = NULL; |
| 122 |
odView[i].pmap = (int4 *)calloc(FL4NELS(res[0]*res[1]), |
| 123 |
sizeof(int4)); |
| 124 |
if (odView[i].pmap == NULL) |
| 125 |
return(0); |
| 126 |
j = odView[i].hlow*odView[i].vlow; |
| 127 |
odView[i].bmap = (struct ODblock *)malloc( |
| 128 |
j * sizeof(struct ODblock)); |
| 129 |
if (odView[i].bmap == NULL) |
| 130 |
return(0); |
| 131 |
DCHECK(count<=0 | nextsamp>=n, |
| 132 |
CONSISTENCY, "counter botch in odInit"); |
| 133 |
if (!i) count = j; |
| 134 |
while (j--) { /* initialize blocks & free lists */ |
| 135 |
odView[i].bmap[j].pthresh = FHUGE; |
| 136 |
odView[i].bmap[j].first = k = nextsamp; |
| 137 |
nextsamp += odView[i].bmap[j].nsamp = |
| 138 |
(n - nextsamp)/count--; |
| 139 |
odView[i].bmap[j].free = k; |
| 140 |
while (++k < nextsamp) |
| 141 |
odS.nextfree(k-1) = k; |
| 142 |
odS.nextfree(k-1) = ENDFREE; |
| 143 |
odView[i].bmap[j].nused = 0; |
| 144 |
} |
| 145 |
} |
| 146 |
CLR4ALL(odS.redraw, odS.nsamp); /* clear redraw flags */ |
| 147 |
for (i = odS.nsamp; i--; ) { /* clear values */ |
| 148 |
odS.ip[i][0] = odS.ip[i][1] = -1; |
| 149 |
odS.brt[i] = TM_NOBRT; |
| 150 |
} |
| 151 |
needmapping |= NEWMAP; /* compute new map on update */ |
| 152 |
return(odS.nsamp); /* return number of samples */ |
| 153 |
} |
| 154 |
|
| 155 |
#undef SAMP32 |
| 156 |
|
| 157 |
|
| 158 |
int |
| 159 |
sampcmp(s0, s1) /* sample order, descending proximity */ |
| 160 |
int *s0, *s1; |
| 161 |
{ |
| 162 |
register double diff = odS.closeness(*s1) - odS.closeness(*s0); |
| 163 |
|
| 164 |
return (diff > FTINY ? 1 : diff < -FTINY ? -1 : 0); |
| 165 |
} |
| 166 |
|
| 167 |
|
| 168 |
int |
| 169 |
odAllocBlockSamp(vn, hh, vh, prox) /* allocate sample from block */ |
| 170 |
int vn, hh, vh; |
| 171 |
double prox; |
| 172 |
{ |
| 173 |
int si[SAMPSPERBLOCK+SAMPSPERBLOCK/4]; |
| 174 |
int hl, vl; |
| 175 |
VIEW *vw; |
| 176 |
FVECT ro, rd; |
| 177 |
int res[2]; |
| 178 |
register struct ODblock *bp; |
| 179 |
register int i, j; |
| 180 |
/* get block */ |
| 181 |
hl = hh*odView[vn].hlow/odView[vn].hhi; |
| 182 |
vl = vh*odView[vn].vlow/odView[vn].vhi; |
| 183 |
bp = odView[vn].bmap + vl*odView[vn].hlow + hl; |
| 184 |
if (prox > bp->pthresh) |
| 185 |
return(-1); /* worse than free list occupants */ |
| 186 |
/* check for duplicate pixel */ |
| 187 |
if (CHK4(odView[vn].pmap, vh*odView[vn].hhi + hh)) |
| 188 |
i = bp->first + bp->nsamp; |
| 189 |
else |
| 190 |
i = -1; |
| 191 |
while (i-- > bp->first) |
| 192 |
if (hh == odS.ip[i][0] && vh == odS.ip[i][1]) { /* found it! */ |
| 193 |
/* search free list for it */ |
| 194 |
if (i == bp->free) |
| 195 |
break; /* special case */ |
| 196 |
if (bp->free != ENDFREE) |
| 197 |
for (j = bp->free; odS.nextfree(j) != ENDFREE; |
| 198 |
j = odS.nextfree(j)) |
| 199 |
if (odS.nextfree(j) == i) { |
| 200 |
odS.nextfree(j) = |
| 201 |
odS.nextfree(i); |
| 202 |
bp->nused++; |
| 203 |
goto gotit; |
| 204 |
} |
| 205 |
if (prox >= 0.999*odS.closeness(i)) |
| 206 |
return(-1); /* previous sample is fine */ |
| 207 |
goto gotit; |
| 208 |
} |
| 209 |
DCHECK(i>=-1, WARNING, "pixel in presence map not found in block"); |
| 210 |
if (bp->free != ENDFREE) { /* allocate from free list */ |
| 211 |
i = bp->free; |
| 212 |
if (odS.ip[i][0] >= 0 & odS.ip[i][1] >= 0) |
| 213 |
CLR4(odView[vn].pmap, odS.ip[i][1]*odView[vn].hhi + |
| 214 |
odS.ip[i][0]); |
| 215 |
bp->free = odS.nextfree(i); |
| 216 |
bp->nused++; |
| 217 |
goto gotit; |
| 218 |
} |
| 219 |
DCHECK(bp->nsamp<=0, CONSISTENCY, |
| 220 |
"no available samples in odAllocBlockSamp"); |
| 221 |
DCHECK(bp->nsamp > sizeof(si)/sizeof(si[0]), CONSISTENCY, |
| 222 |
"too many samples in odAllocBlockSamp"); |
| 223 |
/* free some samples */ |
| 224 |
if ((vw = dev_auxview(vn, res)) == NULL) |
| 225 |
error(CONSISTENCY, "bad view number in odAllocBlockSamp"); |
| 226 |
for (i = bp->nsamp; i--; ) /* figure out which are worse */ |
| 227 |
si[i] = bp->first + i; |
| 228 |
qsort((char *)si, bp->nsamp, sizeof(int), sampcmp); |
| 229 |
i = bp->nsamp*SFREEFRAC + .5; /* put them into free list */ |
| 230 |
if (i >= bp->nsamp) i = bp->nsamp-1; /* paranoia */ |
| 231 |
bp->pthresh = odS.closeness(si[i]); /* new proximity threshold */ |
| 232 |
while (--i > 0) { |
| 233 |
odS.nextfree(si[i]) = bp->free; |
| 234 |
bp->free = si[i]; |
| 235 |
bp->nused--; |
| 236 |
} |
| 237 |
i = si[0]; /* use worst sample */ |
| 238 |
CLR4(odView[vn].pmap, odS.ip[i][1]*odView[vn].hhi + odS.ip[i][0]); |
| 239 |
gotit: |
| 240 |
odS.ip[i][0] = hh; |
| 241 |
odS.ip[i][1] = vh; |
| 242 |
odS.closeness(i) = prox; |
| 243 |
SET4(odView[vn].pmap, vh*odView[vn].hhi + hh); |
| 244 |
return(i); |
| 245 |
} |
| 246 |
|
| 247 |
|
| 248 |
odSample(c, d, p) /* add a sample value */ |
| 249 |
COLR c; |
| 250 |
FVECT d, p; |
| 251 |
{ |
| 252 |
FVECT disp; |
| 253 |
double d0, d1, h, v, prox; |
| 254 |
register VIEW *vw; |
| 255 |
int hh, vh; |
| 256 |
int res[2]; |
| 257 |
register int i, id; |
| 258 |
|
| 259 |
DCHECK(odS.nsamp<=0, CONSISTENCY, "no samples allocated in odSample"); |
| 260 |
/* add value to each view */ |
| 261 |
for (i = 0; (vw = dev_auxview(i, res)) != NULL; i++) { |
| 262 |
DCHECK(i>=odNViews, CONSISTENCY, "too many views in odSample"); |
| 263 |
CHECK(vw->type!=VT_PER, INTERNAL, |
| 264 |
"cannot handle non-perspective views"); |
| 265 |
if (p != NULL) { /* compute view position */ |
| 266 |
VSUB(disp, p, vw->vp); |
| 267 |
d0 = DOT(disp, vw->vdir); |
| 268 |
if (d0 <= vw->vfore+FTINY) |
| 269 |
continue; /* too close */ |
| 270 |
} else { |
| 271 |
VCOPY(disp, d); |
| 272 |
d0 = DOT(disp, vw->vdir); |
| 273 |
if (d0 <= FTINY) /* behind view */ |
| 274 |
continue; |
| 275 |
} |
| 276 |
h = DOT(disp,vw->hvec)/(d0*vw->hn2) + 0.5 - vw->hoff; |
| 277 |
if (h < 0. || h >= 1.) |
| 278 |
continue; /* left or right */ |
| 279 |
v = DOT(disp,vw->vvec)/(d0*vw->vn2) + 0.5 - vw->voff; |
| 280 |
if (v < 0. || v >= 1.) |
| 281 |
continue; /* above or below */ |
| 282 |
hh = h * res[0]; |
| 283 |
vh = v * res[1]; |
| 284 |
if (odView[i].dmap != NULL) { /* check depth */ |
| 285 |
d1 = odView[i].dmap[vh*res[0] + hh]; |
| 286 |
if (d1 < 0.99*FHUGE && (d0 > (1.+DEPTHEPS)*d1 || |
| 287 |
(1.+DEPTHEPS)*d0 < d1)) |
| 288 |
continue; /* occlusion error */ |
| 289 |
} |
| 290 |
if (p != NULL) { /* compute closeness (sin^2) */ |
| 291 |
d1 = DOT(disp, d); |
| 292 |
prox = 1. - d1*d1/DOT(disp,disp); |
| 293 |
} else |
| 294 |
prox = 0.; |
| 295 |
/* allocate sample */ |
| 296 |
id = odAllocBlockSamp(i, hh, vh, prox); |
| 297 |
if (id < 0) |
| 298 |
continue; /* not good enough */ |
| 299 |
/* convert color */ |
| 300 |
tmCvColrs(&odS.brt[id], odS.chr[id], c, 1); |
| 301 |
if (imm_mode | needmapping) /* if immediate mode */ |
| 302 |
needmapping |= NEWRGB; /* map it later */ |
| 303 |
else /* else map it now */ |
| 304 |
tmMapPixels(odS.rgb[id], &odS.brt[id], odS.chr[id], 1); |
| 305 |
SET4(odS.redraw, id); /* mark for redraw */ |
| 306 |
} |
| 307 |
} |
| 308 |
|
| 309 |
|
| 310 |
odRemap(newhist) /* recompute tone mapping */ |
| 311 |
int newhist; |
| 312 |
{ |
| 313 |
needmapping |= NEWMAP|NEWRGB; |
| 314 |
if (newhist) |
| 315 |
needmapping |= NEWHIST; |
| 316 |
} |
| 317 |
|
| 318 |
|
| 319 |
odRedraw(vn, hmin, vmin, hmax, vmax) /* redraw view region */ |
| 320 |
int vn, hmin, vmin, hmax, vmax; |
| 321 |
{ |
| 322 |
int i, j; |
| 323 |
register struct ODblock *bp; |
| 324 |
register int k; |
| 325 |
|
| 326 |
if (vn<0 | vn>=odNViews) |
| 327 |
return; |
| 328 |
/* check view limits */ |
| 329 |
if (hmin < 0) hmin = 0; |
| 330 |
if (hmax >= odView[vn].hhi) hmax = odView[vn].hhi-1; |
| 331 |
if (vmin < 0) vmin = 0; |
| 332 |
if (vmax >= odView[vn].vhi) vmax = odView[vn].vhi-1; |
| 333 |
if (hmax <= hmin | vmax <= vmin) |
| 334 |
return; |
| 335 |
/* convert to low resolution */ |
| 336 |
hmin = hmin * odView[vn].hlow / odView[vn].hhi; |
| 337 |
hmax = hmax * odView[vn].hlow / odView[vn].hhi; |
| 338 |
vmin = vmin * odView[vn].vlow / odView[vn].vhi; |
| 339 |
vmax = vmax * odView[vn].vlow / odView[vn].vhi; |
| 340 |
/* mark block samples for redraw, inclusive */ |
| 341 |
for (i = hmin; i <= hmax; i++) |
| 342 |
for (j = vmin; j <= vmax; j++) { |
| 343 |
bp = odView[vn].bmap + j*odView[vn].hlow + i; |
| 344 |
for (k = bp->nsamp; k--; ) |
| 345 |
if (odS.ip[bp->first+k][0] >= 0) |
| 346 |
SET4(odS.redraw, bp->first+k); |
| 347 |
} |
| 348 |
} |
| 349 |
|
| 350 |
|
| 351 |
odDepthMap(vn, dm) /* assign depth map for view */ |
| 352 |
int vn; |
| 353 |
GLfloat *dm; |
| 354 |
{ |
| 355 |
double d0, d1; |
| 356 |
int i, j, hmin, hmax, vmin, vmax; |
| 357 |
register int k, l; |
| 358 |
|
| 359 |
if (dm == NULL) { /* free edge map */ |
| 360 |
if (vn<0 | vn>=odNViews) |
| 361 |
return; /* too late -- they're gone! */ |
| 362 |
if (odView[vn].emap != NULL) |
| 363 |
free((char *)odView[vn].emap); |
| 364 |
odView[vn].emap = NULL; |
| 365 |
odView[vn].dmap = NULL; |
| 366 |
return; |
| 367 |
} |
| 368 |
DCHECK(vn<0 | vn>=odNViews, CONSISTENCY, |
| 369 |
"bad view number in odDepthMap"); |
| 370 |
odView[vn].dmap = dm; /* initialize edge map */ |
| 371 |
if (odView[vn].emap == NULL) { |
| 372 |
odView[vn].emap = (int4 *)malloc( |
| 373 |
FL4NELS(odView[vn].hlow*odView[vn].vlow)*sizeof(int4)); |
| 374 |
if (odView[vn].emap == NULL) |
| 375 |
error(SYSTEM, "out of memory in odDepthMap"); |
| 376 |
} |
| 377 |
CLR4ALL(odView[vn].emap, odView[vn].hlow*odView[vn].vlow); |
| 378 |
/* compute edge map */ |
| 379 |
vmin = odView[vn].vhi; /* enter loopsville */ |
| 380 |
for (j = odView[vn].vlow; j--; ) { |
| 381 |
vmax = vmin; |
| 382 |
vmin = j*odView[vn].vhi/odView[vn].vlow; |
| 383 |
hmin = odView[vn].hhi; |
| 384 |
for (i = odView[vn].hlow; i--; ) { |
| 385 |
hmax = hmin; |
| 386 |
hmin = i*odView[vn].hhi/odView[vn].hlow; |
| 387 |
for (l = vmin; l < vmax; l++) { /* vertical edges */ |
| 388 |
d1 = dm[l*odView[vn].hhi+hmin]; |
| 389 |
for (k = hmin+1; k < hmax; k++) { |
| 390 |
d0 = d1; |
| 391 |
d1 = dm[l*odView[vn].hhi+k]; |
| 392 |
if (d0 > (1.+DEPTHEPS)*d1 || |
| 393 |
(1.+DEPTHEPS)*d0 < d1) { |
| 394 |
SET4(odView[vn].emap, |
| 395 |
j*odView[vn].hlow + i); |
| 396 |
break; |
| 397 |
} |
| 398 |
} |
| 399 |
if (k < hmax) |
| 400 |
break; |
| 401 |
} |
| 402 |
if (l < vmax) |
| 403 |
continue; |
| 404 |
for (k = hmin; k < hmax; k++) { /* horizontal edges */ |
| 405 |
d1 = dm[vmin*odView[vn].hhi+k]; |
| 406 |
for (l = vmin+1; l < vmax; l++) { |
| 407 |
d0 = d1; |
| 408 |
d1 = dm[l*odView[vn].hhi+k]; |
| 409 |
if (d0 > (1.+DEPTHEPS)*d1 || |
| 410 |
(1.+DEPTHEPS)*d0 < d1) { |
| 411 |
SET4(odView[vn].emap, |
| 412 |
j*odView[vn].hlow + i); |
| 413 |
break; |
| 414 |
} |
| 415 |
} |
| 416 |
if (l < vmax) |
| 417 |
break; |
| 418 |
} |
| 419 |
} |
| 420 |
} |
| 421 |
} |
| 422 |
|
| 423 |
|
| 424 |
odUpdate(vn) /* update this view */ |
| 425 |
int vn; |
| 426 |
{ |
| 427 |
register int i, j; |
| 428 |
|
| 429 |
DCHECK(vn<0 | vn>=odNViews, CONSISTENCY, |
| 430 |
"bad view number in odUpdate"); |
| 431 |
/* need to do some tone mapping? */ |
| 432 |
if (needmapping & NEWRGB) { |
| 433 |
if (needmapping & NEWMAP) { |
| 434 |
if (needmapping & NEWHIST) |
| 435 |
tmClearHisto(); |
| 436 |
if (tmAddHisto(odS.brt,odS.nsamp,1) != TM_E_OK) |
| 437 |
return; |
| 438 |
if (tmComputeMapping(0.,0.,0.) != TM_E_OK) |
| 439 |
return; |
| 440 |
for (i = odS.nsamp; i--; ) /* redraw all */ |
| 441 |
if (odS.ip[i][0] >= 0) |
| 442 |
SET4(odS.redraw, i); |
| 443 |
} |
| 444 |
if (tmMapPixels(odS.rgb,odS.brt,odS.chr,odS.nsamp) != TM_E_OK) |
| 445 |
return; |
| 446 |
needmapping = 0; /* reset flag */ |
| 447 |
} |
| 448 |
/* draw samples flagged for redraw */ |
| 449 |
for (j = FL4NELS(odS.nsamp); j--; ) |
| 450 |
for (i = 0; odS.redraw[j]; i++) /* skips faster */ |
| 451 |
if (odS.redraw[j] & 1L<<i) { |
| 452 |
odDrawSamp(vn, (j<<5)+i); |
| 453 |
odS.redraw[j] &= ~(1L<<i); |
| 454 |
} |
| 455 |
} |
| 456 |
|
| 457 |
|
| 458 |
#if 0 |
| 459 |
static |
| 460 |
clip_end(p, o, vp) /* clip line segment to view */ |
| 461 |
GLshort p[3]; |
| 462 |
short o[2]; |
| 463 |
register struct ODview *vp; |
| 464 |
{ |
| 465 |
if (p[0] < 0) { |
| 466 |
p[1] = -o[0]*(p[1]-o[1])/(p[0]-o[0]) + o[1]; |
| 467 |
p[2] = -o[0]*p[2]/(p[0]-o[0]); |
| 468 |
p[0] = 0; |
| 469 |
} else if (p[0] >= vp->hhi) { |
| 470 |
p[1] = (vp->hhi-1-o[0])*(p[1]-o[1])/(p[0]-o[0]) + o[1]; |
| 471 |
p[2] = (vp->hhi-1-o[0])*p[2]/(p[0]-o[0]); |
| 472 |
p[0] = vp->hhi-1; |
| 473 |
} |
| 474 |
if (p[1] < 0) { |
| 475 |
p[0] = -o[1]*(p[0]-o[0])/(p[1]-o[1]) + o[0]; |
| 476 |
p[2] = -o[1]*p[2]/(p[1]-o[1]); |
| 477 |
p[1] = 0; |
| 478 |
} else if (p[1] >= vp->vhi) { |
| 479 |
p[0] = (vp->vhi-1-o[1])*(p[0]-o[0])/(p[1]-o[1]) + o[0]; |
| 480 |
p[2] = (vp->vhi-1-o[1])*p[2]/(p[1]-o[1]); |
| 481 |
p[1] = vp->vhi-1; |
| 482 |
} |
| 483 |
} |
| 484 |
#endif |
| 485 |
|
| 486 |
|
| 487 |
static int |
| 488 |
make_arms(ar, cp, vp, sz) /* make arms for triangle fan */ |
| 489 |
GLshort ar[MAXFAN][3]; |
| 490 |
short cp[2]; |
| 491 |
register struct ODview *vp; |
| 492 |
double sz; |
| 493 |
{ |
| 494 |
int na, dv; |
| 495 |
double hrad, vrad, phi0, phi; |
| 496 |
register int i; |
| 497 |
|
| 498 |
DCHECK(sz > 1, CONSISTENCY, "super-unary size in make_arms"); |
| 499 |
na = MAXFAN*sz*sz + 0.5; /* keep area constant */ |
| 500 |
if (na < MINFAN) na = MINFAN; |
| 501 |
hrad = FANSIZE*sz*vp->hhi/vp->hlow; |
| 502 |
vrad = FANSIZE*sz*vp->vhi/vp->vlow; |
| 503 |
if (hrad*vrad < 2.25) |
| 504 |
hrad = vrad = 1.5; |
| 505 |
phi0 = (2.*PI) * frandom(); |
| 506 |
dv = OMAXDEPTH*sz + 0.5; |
| 507 |
for (i = 0; i < na; i++) { |
| 508 |
phi = phi0 + (2.*PI)*i/na; |
| 509 |
ar[i][0] = cp[0] + tcos(phi)*hrad + 0.5; |
| 510 |
ar[i][1] = cp[1] + tsin(phi)*vrad + 0.5; |
| 511 |
ar[i][2] = dv; |
| 512 |
/* clip_end(ar[i], cp, vp); */ |
| 513 |
} |
| 514 |
return(na); |
| 515 |
} |
| 516 |
|
| 517 |
|
| 518 |
static int |
| 519 |
depthchange(vp, x0, y0, x1, y1) /* check depth discontinuity */ |
| 520 |
register struct ODview *vp; |
| 521 |
int x0, y0, x1, y1; |
| 522 |
{ |
| 523 |
register double d0, d1; |
| 524 |
|
| 525 |
DCHECK(x0<0 | x0>=vp->hhi | y0<0 | y0>=vp->vhi, |
| 526 |
CONSISTENCY, "coordinates off view in depthchange"); |
| 527 |
|
| 528 |
if (x1<0 | x1>=vp->hhi | y1<0 | y1>=vp->vhi) |
| 529 |
return(1); |
| 530 |
|
| 531 |
d0 = vp->dmap[y0*vp->hhi + x0]; |
| 532 |
d1 = vp->dmap[y1*vp->hhi + x1]; |
| 533 |
|
| 534 |
return((1.+DEPTHEPS)*d0 < d1 || d0 > (1.+DEPTHEPS)*d1); |
| 535 |
} |
| 536 |
|
| 537 |
|
| 538 |
static |
| 539 |
clip_edge(p, o, vp) /* clip line segment to depth edge */ |
| 540 |
GLshort p[3]; |
| 541 |
short o[2]; |
| 542 |
register struct ODview *vp; |
| 543 |
{ |
| 544 |
int x, y, xstep, ystep, rise, rise2, run, run2, n; |
| 545 |
|
| 546 |
DCHECK(vp->dmap==NULL, CONSISTENCY, |
| 547 |
"clip_edge called with no depth map"); |
| 548 |
x = o[0]; y = o[1]; |
| 549 |
run = p[0] - x; |
| 550 |
xstep = run > 0 ? 1 : -1; |
| 551 |
run *= xstep; |
| 552 |
rise = p[1] - y; |
| 553 |
ystep = rise > 0 ? 1 : -1; |
| 554 |
rise *= ystep; |
| 555 |
rise2 = run2 = 0; |
| 556 |
if (rise > run) rise2 = 1; |
| 557 |
else run2 = 1; |
| 558 |
n = rise + run; |
| 559 |
while (n--) /* run out arm, checking depth */ |
| 560 |
if (run2 > rise2) { |
| 561 |
if (depthchange(vp, x, y, x+xstep, y)) |
| 562 |
break; |
| 563 |
x += xstep; |
| 564 |
rise2 += rise; |
| 565 |
} else { |
| 566 |
if (depthchange(vp, x, y, x, y+ystep)) |
| 567 |
break; |
| 568 |
y += ystep; |
| 569 |
run2 += run; |
| 570 |
} |
| 571 |
if (n < 0) /* found something? */ |
| 572 |
return; |
| 573 |
if (run > rise) |
| 574 |
p[2] = (x - o[0])*p[2]/(p[0] - o[0]); |
| 575 |
else |
| 576 |
p[2] = (y - o[1])*p[2]/(p[1] - o[1]); |
| 577 |
p[0] = x; |
| 578 |
p[1] = y; |
| 579 |
} |
| 580 |
|
| 581 |
|
| 582 |
static int |
| 583 |
getblock(vp, h, v) /* get block index */ |
| 584 |
register struct ODview *vp; |
| 585 |
register int h, v; |
| 586 |
{ |
| 587 |
if (h<0 | h>=vp->hhi | v<0 | v>=vp->vhi) |
| 588 |
return(-1); |
| 589 |
return(h*vp->hlow/vp->hhi + v*vp->vlow/vp->vhi*vp->hlow); |
| 590 |
} |
| 591 |
|
| 592 |
|
| 593 |
odDrawSamp(vn, id) /* draw view sample */ |
| 594 |
int vn; |
| 595 |
register int id; |
| 596 |
{ |
| 597 |
GLshort arm[MAXFAN][3]; |
| 598 |
int narms, blockindex, bi1; |
| 599 |
register struct ODview *vp; |
| 600 |
double size; |
| 601 |
int home_edges; |
| 602 |
register int i; |
| 603 |
|
| 604 |
vp = odView + vn; |
| 605 |
blockindex = getblock(vp, odS.ip[id][0], odS.ip[id][1]); |
| 606 |
DCHECK(blockindex<0, CONSISTENCY, "bad sample handed to odDrawSamp"); |
| 607 |
DCHECK(vp->bmap[blockindex].nused <= 0, |
| 608 |
CONSISTENCY, "bad in-use count in odDrawSamp"); |
| 609 |
/* create triangle fan */ |
| 610 |
size = 1./sqrt((double)vp->bmap[blockindex].nused); |
| 611 |
narms = make_arms(arm, odS.ip[id], vp, size); |
| 612 |
if (vp->emap != NULL) { /* check for edge collisions */ |
| 613 |
home_edges = CHK4(vp->emap, blockindex); |
| 614 |
for (i = 0; i < narms; i++) |
| 615 |
/* the following test is flawed, because we could |
| 616 |
* be passing through a block on a diagonal run */ |
| 617 |
if (home_edges || |
| 618 |
( (bi1 = getblock(vp, arm[i][0], arm[i][1])) |
| 619 |
!= blockindex && |
| 620 |
(bi1 < 0 || CHK4(vp->emap, bi1)) )) |
| 621 |
clip_edge(arm[i], odS.ip[id], vp); |
| 622 |
} |
| 623 |
/* draw triangle fan */ |
| 624 |
glColor3ub(odS.rgb[id][0], odS.rgb[id][1], odS.rgb[id][2]); |
| 625 |
glBegin(GL_TRIANGLE_FAN); |
| 626 |
glVertex3s((GLshort)odS.ip[id][0], (GLshort)odS.ip[id][1], (GLshort)0); |
| 627 |
for (i = 0; i < narms; i++) |
| 628 |
glVertex3sv(arm[i]); |
| 629 |
glVertex3sv(arm[0]); /* connect last to first */ |
| 630 |
glEnd(); |
| 631 |
} |
