portals.c

   1
   2 #include "quakedef.h"
   3 #include "polygon.h"
   4 #include "portals.h"
   5
   6 #define MAXRECURSIVEPORTALPLANES 1024
   7 #define MAXRECURSIVEPORTALS 256
   8
   9 static tinyplane_t portalplanes[MAXRECURSIVEPORTALPLANES];
  10 static int ranoutofportalplanes;
  11 static int ranoutofportals;
  12 static float portaltemppoints[2][256][3];
  13 static float portaltemppoints2[256][3];
  14 static int portal_markid = 0;
  15 static float boxpoints[4*3];
  16
  17 static int Portal_PortalThroughPortalPlanes(tinyplane_t *clipplanes, int clipnumplanes, float *targpoints, int targnumpoints, float *out, int maxpoints)
  18 {
  19         int numpoints = targnumpoints, i, w;
  20         if (numpoints < 1)
  21                 return numpoints;
  22         if (maxpoints > 256)
  23                 maxpoints = 256;
  24         w = 0;
  25         memcpy(&portaltemppoints[w][0][0], targpoints, numpoints * 3 * sizeof(float));
  26         for (i = 0;i < clipnumplanes && numpoints > 0;i++)
  27         {
  28                 PolygonF_Divide(numpoints, &portaltemppoints[w][0][0], clipplanes[i].normal[0], clipplanes[i].normal[1], clipplanes[i].normal[2], clipplanes[i].dist, 1.0f/32.0f, 256, &portaltemppoints[1-w][0][0], &numpoints, 0, NULL, NULL, NULL);
  29                 w = 1-w;
  30                 numpoints = min(numpoints, 256);
  31         }
  32         numpoints = min(numpoints, maxpoints);
  33         if (numpoints > 0)
  34                 memcpy(out, &portaltemppoints[w][0][0], numpoints * 3 * sizeof(float));
  35         return numpoints;
  36 }
  37
  38 static int Portal_RecursiveFlowSearch (mleaf_t *leaf, vec3_t eye, int firstclipplane, int numclipplanes)
  39 {
  40         mportal_t *p;
  41         int newpoints, i, prev;
  42         vec3_t center, v1, v2;
  43         tinyplane_t *newplanes;
  44
  45         if (leaf->portalmarkid == portal_markid)
  46                 return true;
  47
  48         // follow portals into other leafs
  49         for (p = leaf->portals;p;p = p->next)
  50         {
  51                 // only flow through portals facing away from the viewer
  52                 if (PlaneDiff(eye, (&p->plane)) < 0)
  53                 {
  54                         newpoints = Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, (float *) p->points, p->numpoints, &portaltemppoints2[0][0], 256);
  55                         if (newpoints < 3)
  56                                 continue;
  57                         else if (firstclipplane + numclipplanes + newpoints > MAXRECURSIVEPORTALPLANES)
  58                                 ranoutofportalplanes = true;
  59                         else
  60                         {
  61                                 // find the center by averaging
  62                                 VectorClear(center);
  63                                 for (i = 0;i < newpoints;i++)
  64                                         VectorAdd(center, portaltemppoints2[i], center);
  65                                 // ixtable is a 1.0f / N table
  66                                 VectorScale(center, ixtable[newpoints], center);
  67                                 // calculate the planes, and make sure the polygon can see it's own center
  68                                 newplanes = &portalplanes[firstclipplane + numclipplanes];
  69                                 for (prev = newpoints - 1, i = 0;i < newpoints;prev = i, i++)
  70                                 {
  71                                         VectorSubtract(eye, portaltemppoints2[i], v1);
  72                                         VectorSubtract(portaltemppoints2[prev], portaltemppoints2[i], v2);
  73                                         CrossProduct(v1, v2, newplanes[i].normal);
  74                                         VectorNormalize(newplanes[i].normal);
  75                                         newplanes[i].dist = DotProduct(eye, newplanes[i].normal);
  76                                         if (DotProduct(newplanes[i].normal, center) <= newplanes[i].dist)
  77                                         {
  78                                                 // polygon can't see it's own center, discard and use parent portal
  79                                                 break;
  80                                         }
  81                                 }
  82                                 if (i == newpoints)
  83                                 {
  84                                         if (Portal_RecursiveFlowSearch(p->past, eye, firstclipplane + numclipplanes, newpoints))
  85                                                 return true;
  86                                 }
  87                                 else
  88                                 {
  89                                         if (Portal_RecursiveFlowSearch(p->past, eye, firstclipplane, numclipplanes))
  90                                                 return true;
  91                                 }
  92                         }
  93                 }
  94         }
  95
  96         return false;
  97 }
  98
  99 static void Portal_PolygonRecursiveMarkLeafs(mnode_t *node, float *polypoints, int numpoints)
 100 {
 101         int i, front;
 102         float *p;
 103
 104 loc0:
 105         if (!node->plane)
 106         {
 107                 ((mleaf_t *)node)->portalmarkid = portal_markid;
 108                 return;
 109         }
 110
 111         front = 0;
 112         for (i = 0, p = polypoints;i < numpoints;i++, p += 3)
 113         {
 114                 if (DotProduct(p, node->plane->normal) > node->plane->dist)
 115                         front++;
 116         }
 117         if (front > 0)
 118         {
 119                 if (front == numpoints)
 120                 {
 121                         node = node->children[0];
 122                         goto loc0;
 123                 }
 124                 else
 125                         Portal_PolygonRecursiveMarkLeafs(node->children[0], polypoints, numpoints);
 126         }
 127         node = node->children[1];
 128         goto loc0;
 129 }
 130
 131 int Portal_CheckPolygon(model_t *model, vec3_t eye, float *polypoints, int numpoints)
 132 {
 133         int i, prev, returnvalue;
 134         mleaf_t *eyeleaf;
 135         vec3_t center, v1, v2;
 136
 137         // if there is no model, it can not block visibility
 138         if (model == NULL || !model->brush.PointInLeaf)
 139                 return true;
 140
 141         portal_markid++;
 142
 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                 VectorNormalize(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 typedef struct portalrecursioninfo_s
 268 {
 269         int exact;
 270         int numfrustumplanes;
 271         vec3_t boxmins;
 272         vec3_t boxmaxs;
 273         int numsurfaces;
 274         int *surfacelist;
 275         unsigned char *surfacepvs;
 276         int numleafs;
 277         unsigned char *visitingleafpvs; // used to prevent infinite loops
 278         int *leaflist;
 279         unsigned char *leafpvs;
 280         unsigned char *shadowtrispvs;
 281         unsigned char *lighttrispvs;
 282         model_t *model;
 283         vec3_t eye;
 284         float *updateleafsmins;
 285         float *updateleafsmaxs;
 286 }
 287 portalrecursioninfo_t;
 288
 289 static void Portal_RecursiveFlow (portalrecursioninfo_t *info, mleaf_t *leaf, int firstclipplane, int numclipplanes)
 290 {
 291         mportal_t *p;
 292         int newpoints, i, prev;
 293         float dist;
 294         vec3_t center;
 295         tinyplane_t *newplanes;
 296         int leafindex = leaf - info->model->brush.data_leafs;
 297
 298         if (CHECKPVSBIT(info->visitingleafpvs, leafindex))
 299                 return; // recursive loop of leafs (cmc.bsp for megatf coop)
 300
 301         SETPVSBIT(info->visitingleafpvs, leafindex);
 302
 303         for (i = 0;i < 3;i++)
 304         {
 305                 if (info->updateleafsmins && info->updateleafsmins[i] > leaf->mins[i]) info->updateleafsmins[i] = leaf->mins[i];
 306                 if (info->updateleafsmaxs && info->updateleafsmaxs[i] < leaf->maxs[i]) info->updateleafsmaxs[i] = leaf->maxs[i];
 307         }
 308
 309
 310         if (info->leafpvs)
 311         {
 312                 if (!CHECKPVSBIT(info->leafpvs, leafindex))
 313                 {
 314                         SETPVSBIT(info->leafpvs, leafindex);
 315                         info->leaflist[info->numleafs++] = leafindex;
 316                 }
 317         }
 318
 319         // mark surfaces in leaf that can be seen through portal
 320         if (leaf->numleafsurfaces && info->surfacepvs)
 321         {
 322                 for (i = 0;i < leaf->numleafsurfaces;i++)
 323                 {
 324                         int surfaceindex = leaf->firstleafsurface[i];
 325                         msurface_t *surface = info->model->data_surfaces + surfaceindex;
 326                         if (BoxesOverlap(surface->mins, surface->maxs, info->boxmins, info->boxmaxs))
 327                         {
 328                                 qbool insidebox = BoxInsideBox(surface->mins, surface->maxs, info->boxmins, info->boxmaxs);
 329                                 qbool addedtris = false;
 330                                 int t, tend;
 331                                 const int *elements;
 332                                 const float *vertex3f;
 333                                 float v[9];
 334                                 vertex3f = info->model->surfmesh.data_vertex3f;
 335                                 elements = (info->model->surfmesh.data_element3i + 3 * surface->num_firsttriangle);
 336                                 for (t = surface->num_firsttriangle, tend = t + surface->num_triangles;t < tend;t++, elements += 3)
 337                                 {
 338                                         VectorCopy(vertex3f + elements[0] * 3, v + 0);
 339                                         VectorCopy(vertex3f + elements[1] * 3, v + 3);
 340                                         VectorCopy(vertex3f + elements[2] * 3, v + 6);
 341                                         if (PointInfrontOfTriangle(info->eye, v + 0, v + 3, v + 6)
 342                                          && (insidebox || TriangleBBoxOverlapsBox(v, v + 3, v + 6, info->boxmins, info->boxmaxs))
 343                                          && (!info->exact || Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, v, 3, &portaltemppoints2[0][0], 256) > 0))
 344                                         {
 345                                                 addedtris = true;
 346                                                 if (info->shadowtrispvs)
 347                                                         SETPVSBIT(info->shadowtrispvs, t);
 348                                                 if (info->lighttrispvs)
 349                                                         SETPVSBIT(info->lighttrispvs, t);
 350                                         }
 351                                 }
 352                                 if (addedtris && !CHECKPVSBIT(info->surfacepvs, surfaceindex))
 353                                 {
 354                                         SETPVSBIT(info->surfacepvs, surfaceindex);
 355                                         info->surfacelist[info->numsurfaces++] = surfaceindex;
 356                                 }
 357                         }
 358                 }
 359         }
 360
 361         // follow portals into other leafs
 362         for (p = leaf->portals;p;p = p->next)
 363         {
 364                 // only flow through portals facing the viewer
 365                 dist = PlaneDiff(info->eye, (&p->plane));
 366                 if (dist < 0 && BoxesOverlap(p->past->mins, p->past->maxs, info->boxmins, info->boxmaxs))
 367                 {
 368                         newpoints = Portal_PortalThroughPortalPlanes(&portalplanes[firstclipplane], numclipplanes, (float *) p->points, p->numpoints, &portaltemppoints2[0][0], 256);
 369                         if (newpoints < 3)
 370                                 continue;
 371                         else if (firstclipplane + numclipplanes + newpoints > MAXRECURSIVEPORTALPLANES)
 372                                 ranoutofportalplanes = true;
 373                         else
 374                         {
 375                                 // find the center by averaging
 376                                 VectorClear(center);
 377                                 for (i = 0;i < newpoints;i++)
 378                                         VectorAdd(center, portaltemppoints2[i], center);
 379                                 // ixtable is a 1.0f / N table
 380                                 VectorScale(center, ixtable[newpoints], center);
 381                                 // calculate the planes, and make sure the polygon can see its own center
 382                                 newplanes = &portalplanes[firstclipplane + numclipplanes];
 383                                 for (prev = newpoints - 1, i = 0;i < newpoints;prev = i, i++)
 384                                 {
 385                                         TriangleNormal(portaltemppoints2[prev], portaltemppoints2[i], info->eye, newplanes[i].normal);
 386                                         VectorNormalize(newplanes[i].normal);
 387                                         newplanes[i].dist = DotProduct(info->eye, newplanes[i].normal);
 388                                         if (DotProduct(newplanes[i].normal, center) <= newplanes[i].dist)
 389                                         {
 390                                                 // polygon can't see its own center, discard and use parent portal
 391                                                 break;
 392                                         }
 393                                 }
 394                                 if (i == newpoints)
 395                                         Portal_RecursiveFlow(info, p->past, firstclipplane + numclipplanes, newpoints);
 396                                 else
 397                                         Portal_RecursiveFlow(info, p->past, firstclipplane, numclipplanes);
 398                         }
 399                 }
 400         }
 401
 402         CLEARPVSBIT(info->visitingleafpvs, leafindex);
 403 }
 404
 405 static void Portal_RecursiveFindLeafForFlow(portalrecursioninfo_t *info, mnode_t *node)
 406 {
 407         if (node->plane)
 408         {
 409                 float f = DotProduct(info->eye, node->plane->normal) - node->plane->dist;
 410                 if (f > -0.1)
 411                         Portal_RecursiveFindLeafForFlow(info, node->children[0]);
 412                 if (f < 0.1)
 413                         Portal_RecursiveFindLeafForFlow(info, node->children[1]);
 414         }
 415         else
 416         {
 417                 mleaf_t *leaf = (mleaf_t *)node;
 418                 if (leaf->clusterindex >= 0)
 419                         Portal_RecursiveFlow(info, leaf, 0, info->numfrustumplanes);
 420         }
 421 }
 422
 423 void Portal_Visibility(model_t *model, const vec3_t eye, int *leaflist, unsigned char *leafpvs, int *numleafspointer, int *surfacelist, unsigned char *surfacepvs, int *numsurfacespointer, const mplane_t *frustumplanes, int numfrustumplanes, int exact, const float *boxmins, const float *boxmaxs, float *updateleafsmins, float *updateleafsmaxs, unsigned char *shadowtrispvs, unsigned char *lighttrispvs, unsigned char *visitingleafpvs)
 424 {
 425         int i;
 426         portalrecursioninfo_t info;
 427
 428         // if there is no model, it can not block visibility
 429         if (model == NULL)
 430         {
 431                 Con_Print("Portal_Visibility: NULL model\n");
 432                 return;
 433         }
 434
 435         if (!model->brush.data_nodes)
 436         {
 437                 Con_Print("Portal_Visibility: not a brush model\n");
 438                 return;
 439         }
 440
 441         // put frustum planes (if any) into tinyplane format at start of buffer
 442         for (i = 0;i < numfrustumplanes;i++)
 443         {
 444                 VectorCopy(frustumplanes[i].normal, portalplanes[i].normal);
 445                 portalplanes[i].dist = frustumplanes[i].dist;
 446         }
 447
 448         ranoutofportalplanes = false;
 449         ranoutofportals = false;
 450
 451         VectorCopy(boxmins, info.boxmins);
 452         VectorCopy(boxmaxs, info.boxmaxs);
 453         info.exact = exact;
 454         info.numsurfaces = 0;
 455         info.surfacelist = surfacelist;
 456         info.surfacepvs = surfacepvs;
 457         info.numleafs = 0;
 458         info.visitingleafpvs = visitingleafpvs;
 459         info.leaflist = leaflist;
 460         info.leafpvs = leafpvs;
 461         info.model = model;
 462         VectorCopy(eye, info.eye);
 463         info.numfrustumplanes = numfrustumplanes;
 464         info.updateleafsmins = updateleafsmins;
 465         info.updateleafsmaxs = updateleafsmaxs;
 466         info.shadowtrispvs = shadowtrispvs;
 467         info.lighttrispvs = lighttrispvs;
 468
 469         Portal_RecursiveFindLeafForFlow(&info, model->brush.data_nodes);
 470
 471         if (ranoutofportalplanes)
 472                 Con_Printf("Portal_RecursiveFlow: ran out of %d plane stack when recursing through portals\n", MAXRECURSIVEPORTALPLANES);
 473         if (ranoutofportals)
 474                 Con_Printf("Portal_RecursiveFlow: ran out of %d portal stack when recursing through portals\n", MAXRECURSIVEPORTALS);
 475         if (numsurfacespointer)
 476                 *numsurfacespointer = info.numsurfaces;
 477         if (numleafspointer)
 478                 *numleafspointer = info.numleafs;
 479 }
 480