tools/quake3/q3map2/facebsp.c

   1 /* -------------------------------------------------------------------------------
   2
   3    Copyright (C) 1999-2007 id Software, Inc. and contributors.
   4    For a list of contributors, see the accompanying CONTRIBUTORS file.
   5
   6    This file is part of GtkRadiant.
   7
   8    GtkRadiant is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    GtkRadiant is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GtkRadiant; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21
  22    ----------------------------------------------------------------------------------
  23
  24    This code has been altered significantly from its original form, to support
  25    several games based on the Quake III Arena engine, in the form of "Q3Map2."
  26
  27    ------------------------------------------------------------------------------- */
  28
  29
  30
  31 /* marker */
  32 #define FACEBSP_C
  33
  34
  35
  36 /* dependencies */
  37 #include "q3map2.h"
  38
  39
  40
  41 int c_faceLeafs;
  42
  43
  44 /*
  45    ================
  46    AllocBspFace
  47    ================
  48  */
  49 face_t  *AllocBspFace( void ) {
  50         face_t  *f;
  51
  52         f = safe_malloc( sizeof( *f ) );
  53         memset( f, 0, sizeof( *f ) );
  54
  55         return f;
  56 }
  57
  58
  59
  60 /*
  61    ================
  62    FreeBspFace
  63    ================
  64  */
  65 void    FreeBspFace( face_t *f ) {
  66         if ( f->w ) {
  67                 FreeWinding( f->w );
  68         }
  69         free( f );
  70 }
  71
  72
  73
  74 /*
  75    SelectSplitPlaneNum()
  76    finds the best split plane for this node
  77  */
  78
  79 static void SelectSplitPlaneNum( node_t *node, face_t *list, int *splitPlaneNum, int *compileFlags ){
  80         face_t *split;
  81         face_t *check;
  82         face_t *bestSplit;
  83         int splits, facing, front, back;
  84         int side;
  85         plane_t *plane;
  86         int value, bestValue;
  87         int i;
  88         vec3_t normal;
  89         float dist;
  90         int planenum;
  91         float sizeBias;
  92
  93         /* ydnar: set some defaults */
  94         *splitPlaneNum = -1; /* leaf */
  95         *compileFlags = 0;
  96
  97         /* ydnar 2002-06-24: changed this to split on z-axis as well */
  98         /* ydnar 2002-09-21: changed blocksize to be a vector, so mappers can specify a 3 element value */
  99
 100         /* if it is crossing a block boundary, force a split */
 101         for ( i = 0; i < 3; i++ )
 102         {
 103                 if ( blockSize[ i ] <= 0 ) {
 104                         continue;
 105                 }
 106                 dist = blockSize[ i ] * ( floor( node->mins[ i ] / blockSize[ i ] ) + 1 );
 107                 if ( node->maxs[ i ] > dist ) {
 108                         VectorClear( normal );
 109                         normal[ i ] = 1;
 110                         planenum = FindFloatPlane( normal, dist, 0, NULL );
 111                         *splitPlaneNum = planenum;
 112                         return;
 113                 }
 114         }
 115
 116         /* pick one of the face planes */
 117         bestValue = -99999;
 118         bestSplit = list;
 119
 120
 121         // div0: this check causes detail/structural mixes
 122         //for( split = list; split; split = split->next )
 123         //      split->checked = qfalse;
 124
 125         for ( split = list; split; split = split->next )
 126         {
 127                 //if ( split->checked )
 128                 //      continue;
 129
 130                 plane = &mapplanes[ split->planenum ];
 131                 splits = 0;
 132                 facing = 0;
 133                 front = 0;
 134                 back = 0;
 135                 for ( check = list ; check ; check = check->next ) {
 136                         if ( check->planenum == split->planenum ) {
 137                                 facing++;
 138                                 //check->checked = qtrue;       // won't need to test this plane again
 139                                 continue;
 140                         }
 141                         side = WindingOnPlaneSide( check->w, plane->normal, plane->dist );
 142                         if ( side == SIDE_CROSS ) {
 143                                 splits++;
 144                         }
 145                         else if ( side == SIDE_FRONT ) {
 146                                 front++;
 147                         }
 148                         else if ( side == SIDE_BACK ) {
 149                                 back++;
 150                         }
 151                 }
 152
 153                 if ( bspAlternateSplitWeights ) {
 154                         // from 27
 155
 156                         //Bigger is better
 157                         sizeBias = WindingArea( split->w );
 158
 159                         //Base score = 20000 perfectly balanced
 160                         value = 20000 - ( abs( front - back ) );
 161                         value -= plane->counter; // If we've already used this plane sometime in the past try not to use it again
 162                         value -= facing ;       // if we're going to have alot of other surfs use this plane, we want to get it in quickly.
 163                         value -= splits * 5;        //more splits = bad
 164                         value +=  sizeBias * 10; //We want a huge score bias based on plane size
 165                 }
 166                 else
 167                 {
 168                         value =  5 * facing - 5 * splits; // - abs(front-back);
 169                         if ( plane->type < 3 ) {
 170                                 value += 5;       // axial is better
 171                         }
 172                 }
 173
 174                 value += split->priority;       // prioritize hints higher
 175
 176                 if ( value > bestValue ) {
 177                         bestValue = value;
 178                         bestSplit = split;
 179                 }
 180         }
 181
 182         /* nothing, we have a leaf */
 183         if ( bestValue == -99999 ) {
 184                 return;
 185         }
 186
 187         /* set best split data */
 188         *splitPlaneNum = bestSplit->planenum;
 189         *compileFlags = bestSplit->compileFlags;
 190
 191         if ( *splitPlaneNum > -1 ) {
 192                 mapplanes[ *splitPlaneNum ].counter++;
 193         }
 194 }
 195
 196
 197
 198 /*
 199    CountFaceList()
 200    counts bsp faces in the linked list
 201  */
 202
 203 int CountFaceList( face_t *list ){
 204         int c;
 205
 206
 207         c = 0;
 208         for ( ; list != NULL; list = list->next )
 209                 c++;
 210         return c;
 211 }
 212
 213
 214
 215 /*
 216    BuildFaceTree_r()
 217    recursively builds the bsp, splitting on face planes
 218  */
 219
 220 void BuildFaceTree_r( node_t *node, face_t *list ){
 221         face_t      *split;
 222         face_t      *next;
 223         int side;
 224         plane_t     *plane;
 225         face_t      *newFace;
 226         face_t      *childLists[2];
 227         winding_t   *frontWinding, *backWinding;
 228         int i;
 229         int splitPlaneNum, compileFlags;
 230
 231
 232         /* count faces left */
 233         i = CountFaceList( list );
 234
 235         /* select the best split plane */
 236         SelectSplitPlaneNum( node, list, &splitPlaneNum, &compileFlags );
 237
 238         /* if we don't have any more faces, this is a node */
 239         if ( splitPlaneNum == -1 ) {
 240                 node->planenum = PLANENUM_LEAF;
 241                 node->has_structural_children = qfalse;
 242                 c_faceLeafs++;
 243                 return;
 244         }
 245
 246         /* partition the list */
 247         node->planenum = splitPlaneNum;
 248         node->compileFlags = compileFlags;
 249         node->has_structural_children = !( compileFlags & C_DETAIL ) && !node->opaque;
 250         plane = &mapplanes[ splitPlaneNum ];
 251         childLists[0] = NULL;
 252         childLists[1] = NULL;
 253
 254         for ( split = list; split; split = next )
 255         {
 256                 /* set next */
 257                 next = split->next;
 258
 259                 /* don't split by identical plane */
 260                 if ( split->planenum == node->planenum ) {
 261                         FreeBspFace( split );
 262                         continue;
 263                 }
 264
 265                 /* determine which side the face falls on */
 266                 side = WindingOnPlaneSide( split->w, plane->normal, plane->dist );
 267
 268                 /* switch on side */
 269                 if ( side == SIDE_CROSS ) {
 270                         /* strict; if no winding is left, we have a "virtually identical" plane and don't want to split by it */
 271                         ClipWindingEpsilonStrict( split->w, plane->normal, plane->dist, CLIP_EPSILON * 2,
 272                                                                 &frontWinding, &backWinding );
 273                         if ( frontWinding ) {
 274                                 newFace = AllocBspFace();
 275                                 newFace->w = frontWinding;
 276                                 newFace->next = childLists[0];
 277                                 newFace->planenum = split->planenum;
 278                                 newFace->priority = split->priority;
 279                                 newFace->compileFlags = split->compileFlags;
 280                                 childLists[0] = newFace;
 281                         }
 282                         if ( backWinding ) {
 283                                 newFace = AllocBspFace();
 284                                 newFace->w = backWinding;
 285                                 newFace->next = childLists[1];
 286                                 newFace->planenum = split->planenum;
 287                                 newFace->priority = split->priority;
 288                                 newFace->compileFlags = split->compileFlags;
 289                                 childLists[1] = newFace;
 290                         }
 291                         FreeBspFace( split );
 292                 }
 293                 else if ( side == SIDE_FRONT ) {
 294                         split->next = childLists[0];
 295                         childLists[0] = split;
 296                 }
 297                 else if ( side == SIDE_BACK ) {
 298                         split->next = childLists[1];
 299                         childLists[1] = split;
 300                 }
 301         }
 302
 303
 304         // recursively process children
 305         for ( i = 0 ; i < 2 ; i++ ) {
 306                 node->children[i] = AllocNode();
 307                 node->children[i]->parent = node;
 308                 VectorCopy( node->mins, node->children[i]->mins );
 309                 VectorCopy( node->maxs, node->children[i]->maxs );
 310         }
 311
 312         for ( i = 0 ; i < 3 ; i++ ) {
 313                 if ( plane->normal[i] == 1 ) {
 314                         node->children[0]->mins[i] = plane->dist;
 315                         node->children[1]->maxs[i] = plane->dist;
 316                         break;
 317                 }
 318                 if ( plane->normal[i] == -1 ) {
 319                         node->children[0]->maxs[i] = -plane->dist;
 320                         node->children[1]->mins[i] = -plane->dist;
 321                         break;
 322                 }
 323         }
 324
 325         for ( i = 0 ; i < 2 ; i++ ) {
 326                 BuildFaceTree_r( node->children[i], childLists[i] );
 327                 node->has_structural_children |= node->children[i]->has_structural_children;
 328         }
 329 }
 330
 331
 332 /*
 333    ================
 334    FaceBSP
 335
 336    List will be freed before returning
 337    ================
 338  */
 339 tree_t *FaceBSP( face_t *list ) {
 340         tree_t      *tree;
 341         face_t  *face;
 342         int i;
 343         int count;
 344
 345         Sys_FPrintf( SYS_VRB, "--- FaceBSP ---\n" );
 346
 347         tree = AllocTree();
 348
 349         count = 0;
 350         for ( face = list; face != NULL; face = face->next )
 351         {
 352                 count++;
 353                 for ( i = 0; i < face->w->numpoints; i++ )
 354                 {
 355                         AddPointToBounds( face->w->p[ i ], tree->mins, tree->maxs );
 356                 }
 357         }
 358         Sys_FPrintf( SYS_VRB, "%9d faces\n", count );
 359
 360         for ( i = 0; i < nummapplanes; i++ )
 361         {
 362                 mapplanes[ i ].counter = 0;
 363         }
 364
 365         tree->headnode = AllocNode();
 366         VectorCopy( tree->mins, tree->headnode->mins );
 367         VectorCopy( tree->maxs, tree->headnode->maxs );
 368         c_faceLeafs = 0;
 369
 370         BuildFaceTree_r( tree->headnode, list );
 371
 372         Sys_FPrintf( SYS_VRB, "%9d leafs\n", c_faceLeafs );
 373
 374         return tree;
 375 }
 376
 377
 378
 379 /*
 380    MakeStructuralBSPFaceList()
 381    get structural brush faces
 382  */
 383
 384 face_t *MakeStructuralBSPFaceList( brush_t *list ){
 385         brush_t     *b;
 386         int i;
 387         side_t      *s;
 388         winding_t   *w;
 389         face_t      *f, *flist;
 390
 391
 392         flist = NULL;
 393         for ( b = list; b != NULL; b = b->next )
 394         {
 395                 if ( !deepBSP && b->detail ) {
 396                         continue;
 397                 }
 398
 399                 for ( i = 0; i < b->numsides; i++ )
 400                 {
 401                         /* get side and winding */
 402                         s = &b->sides[ i ];
 403                         w = s->winding;
 404                         if ( w == NULL ) {
 405                                 continue;
 406                         }
 407
 408                         /* ydnar: skip certain faces */
 409                         if ( s->compileFlags & C_SKIP ) {
 410                                 continue;
 411                         }
 412
 413                         /* allocate a face */
 414                         f = AllocBspFace();
 415                         f->w = CopyWinding( w );
 416                         f->planenum = s->planenum & ~1;
 417                         f->compileFlags = s->compileFlags;  /* ydnar */
 418                         if ( b->detail ) {
 419                                 f->compileFlags |= C_DETAIL;
 420                         }
 421
 422                         /* ydnar: set priority */
 423                         f->priority = 0;
 424                         if ( f->compileFlags & C_HINT ) {
 425                                 f->priority += HINT_PRIORITY;
 426                         }
 427                         if ( f->compileFlags & C_ANTIPORTAL ) {
 428                                 f->priority += ANTIPORTAL_PRIORITY;
 429                         }
 430                         if ( f->compileFlags & C_AREAPORTAL ) {
 431                                 f->priority += AREAPORTAL_PRIORITY;
 432                         }
 433                         if ( f->compileFlags & C_DETAIL ) {
 434                                 f->priority += DETAIL_PRIORITY;
 435                         }
 436
 437                         /* get next face */
 438                         f->next = flist;
 439                         flist = f;
 440                 }
 441         }
 442
 443         return flist;
 444 }
 445
 446
 447
 448 /*
 449    MakeVisibleBSPFaceList()
 450    get visible brush faces
 451  */
 452
 453 face_t *MakeVisibleBSPFaceList( brush_t *list ){
 454         brush_t     *b;
 455         int i;
 456         side_t      *s;
 457         winding_t   *w;
 458         face_t      *f, *flist;
 459
 460
 461         flist = NULL;
 462         for ( b = list; b != NULL; b = b->next )
 463         {
 464                 if ( !deepBSP && b->detail ) {
 465                         continue;
 466                 }
 467
 468                 for ( i = 0; i < b->numsides; i++ )
 469                 {
 470                         /* get side and winding */
 471                         s = &b->sides[ i ];
 472                         w = s->visibleHull;
 473                         if ( w == NULL ) {
 474                                 continue;
 475                         }
 476
 477                         /* ydnar: skip certain faces */
 478                         if ( s->compileFlags & C_SKIP ) {
 479                                 continue;
 480                         }
 481
 482                         /* allocate a face */
 483                         f = AllocBspFace();
 484                         f->w = CopyWinding( w );
 485                         f->planenum = s->planenum & ~1;
 486                         f->compileFlags = s->compileFlags;  /* ydnar */
 487                         if ( b->detail ) {
 488                                 f->compileFlags |= C_DETAIL;
 489                         }
 490
 491                         /* ydnar: set priority */
 492                         f->priority = 0;
 493                         if ( f->compileFlags & C_HINT ) {
 494                                 f->priority += HINT_PRIORITY;
 495                         }
 496                         if ( f->compileFlags & C_ANTIPORTAL ) {
 497                                 f->priority += ANTIPORTAL_PRIORITY;
 498                         }
 499                         if ( f->compileFlags & C_AREAPORTAL ) {
 500                                 f->priority += AREAPORTAL_PRIORITY;
 501                         }
 502                         if ( f->compileFlags & C_DETAIL ) {
 503                                 f->priority += DETAIL_PRIORITY;
 504                         }
 505
 506                         /* get next face */
 507                         f->next = flist;
 508                         flist = f;
 509                 }
 510         }
 511
 512         return flist;
 513 }