portals.c

   1
   2 #include "quakedef.h"
   3
   4 #define MAXRECURSIVEPORTALPLANES 1024
   5 #define MAXRECURSIVEPORTALS 256
   6
   7 static tinyplane_t portalplanes[MAXRECURSIVEPORTALPLANES];
   8 static int ranoutofportalplanes;
   9 static int ranoutofportals;
  10 static float portaltemppoints[2][256][3];
  11 static float portaltemppoints2[256][3];
  12 static int portal_markid = 0;
  13 static float boxpoints[4*3];
  14
  15 int Portal_PortalThroughPortalPlanes(tinyplane_t *clipplanes, int clipnumplanes, float *targpoints, int targnumpoints, float *out, int maxpoints)
  16 {
  17         int numpoints, i;
  18         if (targnumpoints < 3)
  19                 return targnumpoints;
  20         if (maxpoints < 3)
  21                 return -1;
  22         numpoints = targnumpoints;
  23         memcpy(&portaltemppoints[0][0][0], targpoints, numpoints * 3 * sizeof(float));
  24         for (i = 0;i < clipnumplanes;i++)
  25         {
  26                 PolygonF_Divide(numpoints, &portaltemppoints[0][0][0], clipplanes[i].normal[0], clipplanes[i].normal[1], clipplanes[i].normal[2], clipplanes[i].dist, 1.0f/32.0f, 256, &portaltemppoints[1][0][0], &numpoints, 0, NULL, NULL);
  27                 if (numpoints < 3)
  28                         return numpoints;
  29                 memcpy(&portaltemppoints[0][0][0], &portaltemppoints[1][0][0], numpoints * 3 * sizeof(float));
  30         }
  31         if (numpoints > maxpoints)
  32                 return -1;
  33         memcpy(out, &portaltemppoints[0][0][0], numpoints * 3 * sizeof(float));
  34         return numpoints;
  35 }
  36
  37 int Portal_RecursiveFlowSearch (mleaf_t *leaf, vec3_t eye, int firstclipplane, int numclipplanes)
  38 {
  39         mportal_t *p;
  40         int newpoints, i, prev;
  41         vec3_t center, v1, v2;
  42         tinyplane_t *newplanes;
  43
  44         if (leaf->portalmarkid == portal_markid)
  45                 return true;
  46
  47         // follow portals into other leafs
  48         for (p = leaf->portals;p;p = p->next)
  49         {
  50                 // only flow through portals facing away from the viewer
  51                 if (PlaneDiff(eye, (&p->plane)) < 0)
  52                 {
  53                         newpoints = Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, (float *) p->points, p->numpoints, &portaltemppoints2[0][0], 256);
  54                         if (newpoints < 3)
  55                                 continue;
  56                         else if (firstclipplane + numclipplanes + newpoints > MAXRECURSIVEPORTALPLANES)
  57                                 ranoutofportalplanes = true;
  58                         else
  59                         {
  60                                 // find the center by averaging
  61                                 VectorClear(center);
  62                                 for (i = 0;i < newpoints;i++)
  63                                         VectorAdd(center, portaltemppoints2[i], center);
  64                                 // ixtable is a 1.0f / N table
  65                                 VectorScale(center, ixtable[newpoints], center);
  66                                 // calculate the planes, and make sure the polygon can see it's own center
  67                                 newplanes = &portalplanes[firstclipplane + numclipplanes];
  68                                 for (prev = newpoints - 1, i = 0;i < newpoints;prev = i, i++)
  69                                 {
  70                                         VectorSubtract(eye, portaltemppoints2[i], v1);
  71                                         VectorSubtract(portaltemppoints2[prev], portaltemppoints2[i], v2);
  72                                         CrossProduct(v1, v2, newplanes[i].normal);
  73                                         VectorNormalizeFast(newplanes[i].normal);
  74                                         newplanes[i].dist = DotProduct(eye, newplanes[i].normal);
  75                                         if (DotProduct(newplanes[i].normal, center) <= newplanes[i].dist)
  76                                         {
  77                                                 // polygon can't see it's own center, discard and use parent portal
  78                                                 break;
  79                                         }
  80                                 }
  81                                 if (i == newpoints)
  82                                 {
  83                                         if (Portal_RecursiveFlowSearch(p->past, eye, firstclipplane + numclipplanes, newpoints))
  84                                                 return true;
  85                                 }
  86                                 else
  87                                 {
  88                                         if (Portal_RecursiveFlowSearch(p->past, eye, firstclipplane, numclipplanes))
  89                                                 return true;
  90                                 }
  91                         }
  92                 }
  93         }
  94
  95         return false;
  96 }
  97
  98 void Portal_PolygonRecursiveMarkLeafs(mnode_t *node, float *polypoints, int numpoints)
  99 {
 100         int i, front;
 101         float *p;
 102
 103 loc0:
 104         if (!node->plane)
 105         {
 106                 ((mleaf_t *)node)->portalmarkid = portal_markid;
 107                 return;
 108         }
 109
 110         front = 0;
 111         for (i = 0, p = polypoints;i < numpoints;i++, p += 3)
 112         {
 113                 if (DotProduct(p, node->plane->normal) > node->plane->dist)
 114                         front++;
 115         }
 116         if (front > 0)
 117         {
 118                 if (front == numpoints)
 119                 {
 120                         node = node->children[0];
 121                         goto loc0;
 122                 }
 123                 else
 124                         Portal_PolygonRecursiveMarkLeafs(node->children[0], polypoints, numpoints);
 125         }
 126         node = node->children[1];
 127         goto loc0;
 128 }
 129
 130 int Portal_CheckPolygon(model_t *model, vec3_t eye, float *polypoints, int numpoints)
 131 {
 132         int i, prev, returnvalue;
 133         mleaf_t *eyeleaf;
 134         vec3_t center, v1, v2;
 135
 136         // if there is no model, it can not block visibility
 137         if (model == NULL || !model->brush.PointInLeaf)
 138                 return true;
 139
 140         portal_markid++;
 141
 142         Mod_CheckLoaded(model);
 143         Portal_PolygonRecursiveMarkLeafs(model->brush.data_nodes, polypoints, numpoints);
 144
 145         eyeleaf = model->brush.PointInLeaf(model, eye);
 146
 147         // find the center by averaging
 148         VectorClear(center);
 149         for (i = 0;i < numpoints;i++)
 150                 VectorAdd(center, (&polypoints[i * 3]), center);
 151         // ixtable is a 1.0f / N table
 152         VectorScale(center, ixtable[numpoints], center);
 153
 154         // calculate the planes, and make sure the polygon can see it's own center
 155         for (prev = numpoints - 1, i = 0;i < numpoints;prev = i, i++)
 156         {
 157                 VectorSubtract(eye, (&polypoints[i * 3]), v1);
 158                 VectorSubtract((&polypoints[prev * 3]), (&polypoints[i * 3]), v2);
 159                 CrossProduct(v1, v2, portalplanes[i].normal);
 160                 VectorNormalizeFast(portalplanes[i].normal);
 161                 portalplanes[i].dist = DotProduct(eye, portalplanes[i].normal);
 162                 if (DotProduct(portalplanes[i].normal, center) <= portalplanes[i].dist)
 163                 {
 164                         // polygon can't see it's own center, discard
 165                         return false;
 166                 }
 167         }
 168
 169         ranoutofportalplanes = false;
 170         ranoutofportals = false;
 171
 172         returnvalue = Portal_RecursiveFlowSearch(eyeleaf, eye, 0, numpoints);
 173
 174         if (ranoutofportalplanes)
 175                 Con_Printf("Portal_RecursiveFlowSearch: ran out of %d plane stack when recursing through portals\n", MAXRECURSIVEPORTALPLANES);
 176         if (ranoutofportals)
 177                 Con_Printf("Portal_RecursiveFlowSearch: ran out of %d portal stack when recursing through portals\n", MAXRECURSIVEPORTALS);
 178
 179         return returnvalue;
 180 }
 181
 182 #define Portal_MinsBoxPolygon(axis, axisvalue, x1, y1, z1, x2, y2, z2, x3, y3, z3, x4, y4, z4) \
 183 {\
 184         if (eye[(axis)] < ((axisvalue) - 0.5f))\
 185         {\
 186                 boxpoints[ 0] = x1;boxpoints[ 1] = y1;boxpoints[ 2] = z1;\
 187                 boxpoints[ 3] = x2;boxpoints[ 4] = y2;boxpoints[ 5] = z2;\
 188                 boxpoints[ 6] = x3;boxpoints[ 7] = y3;boxpoints[ 8] = z3;\
 189                 boxpoints[ 9] = x4;boxpoints[10] = y4;boxpoints[11] = z4;\
 190                 if (Portal_CheckPolygon(model, eye, boxpoints, 4))\
 191                         return true;\
 192         }\
 193 }
 194
 195 #define Portal_MaxsBoxPolygon(axis, axisvalue, x1, y1, z1, x2, y2, z2, x3, y3, z3, x4, y4, z4) \
 196 {\
 197         if (eye[(axis)] > ((axisvalue) + 0.5f))\
 198         {\
 199                 boxpoints[ 0] = x1;boxpoints[ 1] = y1;boxpoints[ 2] = z1;\
 200                 boxpoints[ 3] = x2;boxpoints[ 4] = y2;boxpoints[ 5] = z2;\
 201                 boxpoints[ 6] = x3;boxpoints[ 7] = y3;boxpoints[ 8] = z3;\
 202                 boxpoints[ 9] = x4;boxpoints[10] = y4;boxpoints[11] = z4;\
 203                 if (Portal_CheckPolygon(model, eye, boxpoints, 4))\
 204                         return true;\
 205         }\
 206 }
 207
 208 int Portal_CheckBox(model_t *model, vec3_t eye, vec3_t a, vec3_t b)
 209 {
 210         if (eye[0] >= (a[0] - 1.0f) && eye[0] < (b[0] + 1.0f)
 211          && eye[1] >= (a[1] - 1.0f) && eye[1] < (b[1] + 1.0f)
 212          && eye[2] >= (a[2] - 1.0f) && eye[2] < (b[2] + 1.0f))
 213                 return true;
 214
 215         Portal_MinsBoxPolygon
 216         (
 217                 0, a[0],
 218                 a[0], a[1], a[2],
 219                 a[0], b[1], a[2],
 220                 a[0], b[1], b[2],
 221                 a[0], a[1], b[2]
 222         );
 223         Portal_MaxsBoxPolygon
 224         (
 225                 0, b[0],
 226                 b[0], b[1], a[2],
 227                 b[0], a[1], a[2],
 228                 b[0], a[1], b[2],
 229                 b[0], b[1], b[2]
 230         );
 231         Portal_MinsBoxPolygon
 232         (
 233                 1, a[1],
 234                 b[0], a[1], a[2],
 235                 a[0], a[1], a[2],
 236                 a[0], a[1], b[2],
 237                 b[0], a[1], b[2]
 238         );
 239         Portal_MaxsBoxPolygon
 240         (
 241                 1, b[1],
 242                 a[0], b[1], a[2],
 243                 b[0], b[1], a[2],
 244                 b[0], b[1], b[2],
 245                 a[0], b[1], b[2]
 246         );
 247         Portal_MinsBoxPolygon
 248         (
 249                 2, a[2],
 250                 a[0], a[1], a[2],
 251                 b[0], a[1], a[2],
 252                 b[0], b[1], a[2],
 253                 a[0], b[1], a[2]
 254         );
 255         Portal_MaxsBoxPolygon
 256         (
 257                 2, b[2],
 258                 b[0], a[1], b[2],
 259                 a[0], a[1], b[2],
 260                 a[0], b[1], b[2],
 261                 b[0], b[1], b[2]
 262         );
 263
 264         return false;
 265 }
 266
 267 vec3_t trianglepoints[3];
 268
 269 typedef struct portalrecursioninfo_s
 270 {
 271         int exact;
 272         int numfrustumplanes;
 273         vec3_t boxmins;
 274         vec3_t boxmaxs;
 275         int numsurfaces;
 276         int *surfacelist;
 277         qbyte *surfacepvs;
 278         int numleafs;
 279         int *leaflist;
 280         qbyte *leafpvs;
 281         model_t *model;
 282         vec3_t eye;
 283         float *updateleafsmins;
 284         float *updateleafsmaxs;
 285 }
 286 portalrecursioninfo_t;
 287
 288 void Portal_RecursiveFlow (portalrecursioninfo_t *info, mleaf_t *leaf, int firstclipplane, int numclipplanes)
 289 {
 290         mportal_t *p;
 291         int newpoints, i, prev;
 292         float dist;
 293         vec3_t center, v1, v2;
 294         tinyplane_t *newplanes;
 295
 296         for (i = 0;i < 3;i++)
 297         {
 298                 if (info->updateleafsmins && info->updateleafsmins[i] > leaf->mins[i]) info->updateleafsmins[i] = leaf->mins[i];
 299                 if (info->updateleafsmaxs && info->updateleafsmaxs[i] < leaf->maxs[i]) info->updateleafsmaxs[i] = leaf->maxs[i];
 300         }
 301
 302
 303         if (info->leafpvs)
 304         {
 305                 int leafindex = leaf - info->model->brush.data_leafs;
 306                 if (!CHECKPVSBIT(info->leafpvs, leafindex))
 307                 {
 308                         SETPVSBIT(info->leafpvs, leafindex);
 309                         info->leaflist[info->numleafs++] = leafindex;
 310                 }
 311         }
 312
 313         // mark surfaces in leaf that can be seen through portal
 314         if (leaf->numleafsurfaces && info->surfacepvs)
 315         {
 316                 for (i = 0;i < leaf->numleafsurfaces;i++)
 317                 {
 318                         int surfaceindex = leaf->firstleafsurface[i];
 319                         if (!CHECKPVSBIT(info->surfacepvs, surfaceindex))
 320                         {
 321                                 msurface_t *surface = info->model->brush.data_surfaces + surfaceindex;
 322                                 if (BoxesOverlap(surface->mins, surface->maxs, info->boxmins, info->boxmaxs))
 323                                 {
 324                                         if (info->exact)
 325                                         {
 326                                                 int j;
 327                                                 const int *elements;
 328                                                 const float *vertex3f;
 329                                                 float v[9], trimins[3], trimaxs[3];
 330                                                 vertex3f = surface->groupmesh->data_vertex3f;
 331                                                 elements = (surface->groupmesh->data_element3i + 3 * surface->num_firsttriangle);
 332                                                 for (j = 0;j < surface->num_triangles;j++, elements += 3)
 333                                                 {
 334                                                         VectorCopy(vertex3f + elements[0] * 3, v + 0);
 335                                                         VectorCopy(vertex3f + elements[1] * 3, v + 3);
 336                                                         VectorCopy(vertex3f + elements[2] * 3, v + 6);
 337                                                         if (PointInfrontOfTriangle(info->eye, v + 0, v + 3, v + 6))
 338                                                         {
 339                                                                 trimins[0] = min(v[0], min(v[3], v[6]));
 340                                                                 trimaxs[0] = max(v[0], max(v[3], v[6]));
 341                                                                 trimins[1] = min(v[1], min(v[4], v[7]));
 342                                                                 trimaxs[1] = max(v[1], max(v[4], v[7]));
 343                                                                 trimins[2] = min(v[2], min(v[5], v[8]));
 344                                                                 trimaxs[2] = max(v[2], max(v[5], v[8]));
 345                                                                 if (BoxesOverlap(trimins, trimaxs, info->boxmins, info->boxmaxs) && Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, v, 3, &portaltemppoints2[0][0], 256) >= 3)
 346                                                                 {
 347                                                                         SETPVSBIT(info->surfacepvs, surfaceindex);
 348                                                                         info->surfacelist[info->numsurfaces++] = surfaceindex;
 349                                                                         break;
 350                                                                 }
 351                                                         }
 352                                                 }
 353                                         }
 354                                         else
 355                                         {
 356                                                 SETPVSBIT(info->surfacepvs, surfaceindex);
 357                                                 info->surfacelist[info->numsurfaces++] = surfaceindex;
 358                                         }
 359                                 }
 360                         }
 361                 }
 362         }
 363
 364         // follow portals into other leafs
 365         for (p = leaf->portals;p;p = p->next)
 366         {
 367                 // only flow through portals facing the viewer
 368                 dist = PlaneDiff(info->eye, (&p->plane));
 369                 if (dist < 0 && BoxesOverlap(p->past->mins, p->past->maxs, info->boxmins, info->boxmaxs))
 370                 {
 371                         newpoints = Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, (float *) p->points, p->numpoints, &portaltemppoints2[0][0], 256);
 372                         if (newpoints < 3)
 373                                 continue;
 374                         else if (firstclipplane + numclipplanes + newpoints > MAXRECURSIVEPORTALPLANES)
 375                                 ranoutofportalplanes = true;
 376                         else
 377                         {
 378                                 // find the center by averaging
 379                                 VectorClear(center);
 380                                 for (i = 0;i < newpoints;i++)
 381                                         VectorAdd(center, portaltemppoints2[i], center);
 382                                 // ixtable is a 1.0f / N table
 383                                 VectorScale(center, ixtable[newpoints], center);
 384                                 // calculate the planes, and make sure the polygon can see it's own center
 385                                 newplanes = &portalplanes[firstclipplane + numclipplanes];
 386                                 for (prev = newpoints - 1, i = 0;i < newpoints;prev = i, i++)
 387                                 {
 388                                         VectorSubtract(portaltemppoints2[prev], portaltemppoints2[i], v1);
 389                                         VectorSubtract(info->eye, portaltemppoints2[i], v2);
 390                                         CrossProduct(v1, v2, newplanes[i].normal);
 391                                         VectorNormalizeFast(newplanes[i].normal);
 392                                         newplanes[i].dist = DotProduct(info->eye, newplanes[i].normal);
 393                                         if (DotProduct(newplanes[i].normal, center) <= newplanes[i].dist)
 394                                         {
 395                                                 // polygon can't see it's own center, discard and use parent portal
 396                                                 break;
 397                                         }
 398                                 }
 399                                 if (i == newpoints)
 400                                         Portal_RecursiveFlow(info, p->past, firstclipplane + numclipplanes, newpoints);
 401                                 else
 402                                         Portal_RecursiveFlow(info, p->past, firstclipplane, numclipplanes);
 403                         }
 404                 }
 405         }
 406 }
 407
 408 void Portal_RecursiveFindLeafForFlow(portalrecursioninfo_t *info, mnode_t *node)
 409 {
 410         if (node->plane)
 411         {
 412                 float f = DotProduct(info->eye, node->plane->normal) - node->plane->dist;
 413                 if (f > -0.1)
 414                         Portal_RecursiveFindLeafForFlow(info, node->children[0]);
 415                 if (f < 0.1)
 416                         Portal_RecursiveFindLeafForFlow(info, node->children[1]);
 417         }
 418         else
 419         {
 420                 mleaf_t *leaf = (mleaf_t *)node;
 421                 if (leaf->portals)
 422                         Portal_RecursiveFlow(info, leaf, 0, info->numfrustumplanes);
 423         }
 424 }
 425
 426 void Portal_Visibility(model_t *model, const vec3_t eye, int *leaflist, qbyte *leafpvs, int *numleafspointer, int *surfacelist, qbyte *surfacepvs, int *numsurfacespointer, const mplane_t *frustumplanes, int numfrustumplanes, int exact, const float *boxmins, const float *boxmaxs, float *updateleafsmins, float *updateleafsmaxs)
 427 {
 428         int i;
 429         portalrecursioninfo_t info;
 430
 431         // if there is no model, it can not block visibility
 432         if (model == NULL)
 433         {
 434                 Con_Print("Portal_Visibility: NULL model\n");
 435                 return;
 436         }
 437
 438         Mod_CheckLoaded(model);
 439
 440         if (!model->brush.num_portals)
 441         {
 442                 Con_Print("Portal_Visibility: not a brush model\n");
 443                 return;
 444         }
 445
 446         // put frustum planes (if any) into tinyplane format at start of buffer
 447         for (i = 0;i < numfrustumplanes;i++)
 448         {
 449                 VectorCopy(frustumplanes[i].normal, portalplanes[i].normal);
 450                 portalplanes[i].dist = frustumplanes[i].dist;
 451         }
 452
 453         ranoutofportalplanes = false;
 454         ranoutofportals = false;
 455
 456         VectorCopy(boxmins, info.boxmins);
 457         VectorCopy(boxmaxs, info.boxmaxs);
 458         info.exact = exact;
 459         info.numsurfaces = 0;
 460         info.surfacelist = surfacelist;
 461         info.surfacepvs = surfacepvs;
 462         info.numleafs = 0;
 463         info.leaflist = leaflist;
 464         info.leafpvs = leafpvs;
 465         info.model = model;
 466         VectorCopy(eye, info.eye);
 467         info.numfrustumplanes = numfrustumplanes;
 468         info.updateleafsmins = updateleafsmins;
 469         info.updateleafsmaxs = updateleafsmaxs;
 470
 471         Portal_RecursiveFindLeafForFlow(&info, model->brush.data_nodes);
 472
 473         if (ranoutofportalplanes)
 474                 Con_Printf("Portal_RecursiveFlow: ran out of %d plane stack when recursing through portals\n", MAXRECURSIVEPORTALPLANES);
 475         if (ranoutofportals)
 476                 Con_Printf("Portal_RecursiveFlow: ran out of %d portal stack when recursing through portals\n", MAXRECURSIVEPORTALS);
 477         if (numsurfacespointer)
 478                 *numsurfacespointer = info.numsurfaces;
 479         if (numleafspointer)
 480                 *numleafspointer = info.numleafs;
 481 }
 482