collision.c

   1
   2 #include "quakedef.h"
   3 #include "polygon.h"
   4
   5 #define COLLISION_SNAPSCALE (8.0f)
   6 #define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
   7
   8 cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125"};
   9 cvar_t collision_startnudge = {0, "collision_startnudge", "0"};
  10 cvar_t collision_endnudge = {0, "collision_endnudge", "0"};
  11 cvar_t collision_enternudge = {0, "collision_enternudge", "0"};
  12 cvar_t collision_leavenudge = {0, "collision_leavenudge", "0"};
  13
  14 #if 0
  15 typedef struct
  16 {
  17         // the hull we're tracing through
  18         const hull_t *hull;
  19
  20         // the trace structure to fill in
  21         trace_t *trace;
  22
  23         // start and end of the trace (in model space)
  24         double start[3];
  25         double end[3];
  26
  27         // end - start
  28         double dist[3];
  29
  30         // overrides the CONTENTS_SOLID in the box bsp tree
  31         int boxsupercontents;
  32 }
  33 RecursiveHullCheckTraceInfo_t;
  34
  35 #define HULLCHECKSTATE_EMPTY 0
  36 #define HULLCHECKSTATE_SOLID 1
  37 #define HULLCHECKSTATE_DONE 2
  38
  39 static int RecursiveHullCheck(RecursiveHullCheckTraceInfo_t *t, int num, double p1f, double p2f, double p1[3], double p2[3])
  40 {
  41         // status variables, these don't need to be saved on the stack when
  42         // recursing...  but are because this should be thread-safe
  43         // (note: tracing against a bbox is not thread-safe, yet)
  44         int ret;
  45         mplane_t *plane;
  46         double t1, t2;
  47
  48         // variables that need to be stored on the stack when recursing
  49         dclipnode_t *node;
  50         int side;
  51         double midf, mid[3];
  52
  53         // LordHavoc: a goto!  everyone flee in terror... :)
  54 loc0:
  55         // check for empty
  56         if (num < 0)
  57         {
  58                 num = Mod_Q1BSP_SuperContentsFromNativeContents(NULL, num);
  59                 if (!t->trace->startfound)
  60                 {
  61                         t->trace->startfound = true;
  62                         t->trace->startsupercontents |= num;
  63                 }
  64                 if (num & SUPERCONTENTS_LIQUIDSMASK)
  65                         t->trace->inwater = true;
  66                 if (num == 0)
  67                         t->trace->inopen = true;
  68                 if (num & t->trace->hitsupercontentsmask)
  69                 {
  70                         // if the first leaf is solid, set startsolid
  71                         if (t->trace->allsolid)
  72                                 t->trace->startsolid = true;
  73 #if COLLISIONPARANOID >= 3
  74                         Con_Print("S");
  75 #endif
  76                         return HULLCHECKSTATE_SOLID;
  77                 }
  78                 else
  79                 {
  80                         t->trace->allsolid = false;
  81 #if COLLISIONPARANOID >= 3
  82                         Con_Print("E");
  83 #endif
  84                         return HULLCHECKSTATE_EMPTY;
  85                 }
  86         }
  87
  88         // find the point distances
  89         node = t->hull->clipnodes + num;
  90
  91         plane = t->hull->planes + node->planenum;
  92         if (plane->type < 3)
  93         {
  94                 t1 = p1[plane->type] - plane->dist;
  95                 t2 = p2[plane->type] - plane->dist;
  96         }
  97         else
  98         {
  99                 t1 = DotProduct (plane->normal, p1) - plane->dist;
 100                 t2 = DotProduct (plane->normal, p2) - plane->dist;
 101         }
 102
 103         if (t1 < 0)
 104         {
 105                 if (t2 < 0)
 106                 {
 107 #if COLLISIONPARANOID >= 3
 108                         Con_Print("<");
 109 #endif
 110                         num = node->children[1];
 111                         goto loc0;
 112                 }
 113                 side = 1;
 114         }
 115         else
 116         {
 117                 if (t2 >= 0)
 118                 {
 119 #if COLLISIONPARANOID >= 3
 120                         Con_Print(">");
 121 #endif
 122                         num = node->children[0];
 123                         goto loc0;
 124                 }
 125                 side = 0;
 126         }
 127
 128         // the line intersects, find intersection point
 129         // LordHavoc: this uses the original trace for maximum accuracy
 130 #if COLLISIONPARANOID >= 3
 131         Con_Print("M");
 132 #endif
 133         if (plane->type < 3)
 134         {
 135                 t1 = t->start[plane->type] - plane->dist;
 136                 t2 = t->end[plane->type] - plane->dist;
 137         }
 138         else
 139         {
 140                 t1 = DotProduct (plane->normal, t->start) - plane->dist;
 141                 t2 = DotProduct (plane->normal, t->end) - plane->dist;
 142         }
 143
 144         midf = t1 / (t1 - t2);
 145         midf = bound(p1f, midf, p2f);
 146         VectorMA(t->start, midf, t->dist, mid);
 147
 148         // recurse both sides, front side first
 149         ret = RecursiveHullCheck (t, node->children[side], p1f, midf, p1, mid);
 150         // if this side is not empty, return what it is (solid or done)
 151         if (ret != HULLCHECKSTATE_EMPTY)
 152                 return ret;
 153
 154         ret = RecursiveHullCheck (t, node->children[side ^ 1], midf, p2f, mid, p2);
 155         // if other side is not solid, return what it is (empty or done)
 156         if (ret != HULLCHECKSTATE_SOLID)
 157                 return ret;
 158
 159         // front is air and back is solid, this is the impact point...
 160         if (side)
 161         {
 162                 t->trace->plane.dist = -plane->dist;
 163                 VectorNegate (plane->normal, t->trace->plane.normal);
 164         }
 165         else
 166         {
 167                 t->trace->plane.dist = plane->dist;
 168                 VectorCopy (plane->normal, t->trace->plane.normal);
 169         }
 170
 171         // calculate the true fraction
 172         t1 = DotProduct(t->trace->plane.normal, t->start) - t->trace->plane.dist - collision_startnudge.value;
 173         t2 = DotProduct(t->trace->plane.normal, t->end) - t->trace->plane.dist - collision_endnudge.value;
 174         midf = t1 / (t1 - t2);
 175         t->trace->realfraction = bound(0, midf, 1);
 176
 177         // calculate the return fraction which is nudged off the surface a bit
 178         midf = (t1 - collision_impactnudge.value) / (t1 - t2);
 179         t->trace->fraction = bound(0, midf, 1);
 180
 181 #if COLLISIONPARANOID >= 3
 182         Con_Print("D");
 183 #endif
 184         return HULLCHECKSTATE_DONE;
 185 }
 186
 187 static hull_t box_hull;
 188 static dclipnode_t box_clipnodes[6];
 189 static mplane_t box_planes[6];
 190
 191 void Mod_Q1BSP_Collision_Init (void)
 192 {
 193         int             i;
 194         int             side;
 195
 196         //Set up the planes and clipnodes so that the six floats of a bounding box
 197         //can just be stored out and get a proper hull_t structure.
 198
 199         box_hull.clipnodes = box_clipnodes;
 200         box_hull.planes = box_planes;
 201         box_hull.firstclipnode = 0;
 202         box_hull.lastclipnode = 5;
 203
 204         for (i = 0;i < 6;i++)
 205         {
 206                 box_clipnodes[i].planenum = i;
 207
 208                 side = i&1;
 209
 210                 box_clipnodes[i].children[side] = CONTENTS_EMPTY;
 211                 if (i != 5)
 212                         box_clipnodes[i].children[side^1] = i + 1;
 213                 else
 214                         box_clipnodes[i].children[side^1] = CONTENTS_SOLID;
 215
 216                 box_planes[i].type = i>>1;
 217                 box_planes[i].normal[i>>1] = 1;
 218         }
 219 }
 220
 221 void Collision_ClipTrace_Box(trace_t *trace, const vec3_t cmins, const vec3_t cmaxs, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask, int boxsupercontents)
 222 {
 223         RecursiveHullCheckTraceInfo_t rhc;
 224         // fill in a default trace
 225         memset(&rhc, 0, sizeof(rhc));
 226         memset(trace, 0, sizeof(trace_t));
 227         //To keep everything totally uniform, bounding boxes are turned into small
 228         //BSP trees instead of being compared directly.
 229         // create a temp hull from bounding box sizes
 230         box_planes[0].dist = cmaxs[0] - mins[0];
 231         box_planes[1].dist = cmins[0] - maxs[0];
 232         box_planes[2].dist = cmaxs[1] - mins[1];
 233         box_planes[3].dist = cmins[1] - maxs[1];
 234         box_planes[4].dist = cmaxs[2] - mins[2];
 235         box_planes[5].dist = cmins[2] - maxs[2];
 236         // trace a line through the generated clipping hull
 237         rhc.boxsupercontents = boxsupercontents;
 238         rhc.hull = &box_hull;
 239         rhc.trace = trace;
 240         rhc.trace->hitsupercontentsmask = hitsupercontentsmask;
 241         rhc.trace->fraction = 1;
 242         rhc.trace->realfraction = 1;
 243         rhc.trace->allsolid = true;
 244         VectorCopy(start, rhc.start);
 245         VectorCopy(end, rhc.end);
 246         VectorSubtract(rhc.end, rhc.start, rhc.dist);
 247         Mod_Q1BSP_RecursiveHullCheck(&rhc, rhc.hull->firstclipnode, 0, 1, rhc.start, rhc.end);
 248         VectorMA(rhc.start, rhc.trace->fraction, rhc.dist, rhc.trace->endpos);
 249         if (rhc.trace->startsupercontents)
 250                 rhc.trace->startsupercontents = boxsupercontents;
 251 }
 252 #endif
 253
 254 void Collision_Init (void)
 255 {
 256         Cvar_RegisterVariable(&collision_impactnudge);
 257         Cvar_RegisterVariable(&collision_startnudge);
 258         Cvar_RegisterVariable(&collision_endnudge);
 259         Cvar_RegisterVariable(&collision_enternudge);
 260         Cvar_RegisterVariable(&collision_leavenudge);
 261 }
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276 void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
 277 {
 278         int i;
 279         Con_Printf("3 %s\n%i\n", name, brush->numpoints);
 280         for (i = 0;i < brush->numpoints;i++)
 281                 Con_Printf("%f %f %f\n", brush->points[i].v[0], brush->points[i].v[1], brush->points[i].v[2]);
 282         // FIXME: optimize!
 283         Con_Printf("4\n%i\n", brush->numplanes);
 284         for (i = 0;i < brush->numplanes;i++)
 285                 Con_Printf("%f %f %f %f\n", brush->planes[i].normal[0], brush->planes[i].normal[1], brush->planes[i].normal[2], brush->planes[i].dist);
 286 }
 287
 288 void Collision_ValidateBrush(colbrushf_t *brush)
 289 {
 290         int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
 291         float d;
 292         printbrush = false;
 293         if (!brush->numpoints)
 294         {
 295                 Con_Print("Collision_ValidateBrush: brush with no points!\n");
 296                 printbrush = true;
 297         }
 298 #if 0
 299         // it's ok for a brush to have one point and no planes...
 300         if (brush->numplanes == 0 && brush->numpoints != 1)
 301         {
 302                 Con_Print("Collision_ValidateBrush: brush with no planes and more than one point!\n");
 303                 printbrush = true;
 304         }
 305 #endif
 306         if (brush->numplanes)
 307         {
 308                 pointsoffplanes = 0;
 309                 pointswithinsufficientplanes = 0;
 310                 for (k = 0;k < brush->numplanes;k++)
 311                         if (DotProduct(brush->planes[k].normal, brush->planes[k].normal) < 0.0001f)
 312                                 Con_Printf("Collision_ValidateBrush: plane #%i (%f %f %f %f) is degenerate\n", k, brush->planes[k].normal[0], brush->planes[k].normal[1], brush->planes[k].normal[2], brush->planes[k].dist);
 313                 for (j = 0;j < brush->numpoints;j++)
 314                 {
 315                         pointonplanes = 0;
 316                         for (k = 0;k < brush->numplanes;k++)
 317                         {
 318                                 d = DotProduct(brush->points[j].v, brush->planes[k].normal) - brush->planes[k].dist;
 319                                 if (d > (1.0f / 8.0f))
 320                                 {
 321                                         Con_Printf("Collision_ValidateBrush: point #%i (%f %f %f) infront of plane #%i (%f %f %f %f)\n", j, brush->points[j].v[0], brush->points[j].v[1], brush->points[j].v[2], k, brush->planes[k].normal[0], brush->planes[k].normal[1], brush->planes[k].normal[2], brush->planes[k].dist);
 322                                         printbrush = true;
 323                                 }
 324                                 if (fabs(d) > 0.125f)
 325                                         pointsoffplanes++;
 326                                 else
 327                                         pointonplanes++;
 328                         }
 329                         if (pointonplanes < 3)
 330                                 pointswithinsufficientplanes++;
 331                 }
 332                 if (pointswithinsufficientplanes)
 333                 {
 334                         Con_Print("Collision_ValidateBrush: some points have insufficient planes, every point must be on at least 3 planes to form a corner.\n");
 335                         printbrush = true;
 336                 }
 337                 if (pointsoffplanes == 0) // all points are on all planes
 338                 {
 339                         Con_Print("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
 340                         printbrush = true;
 341                 }
 342         }
 343         if (printbrush)
 344                 Collision_PrintBrushAsQHull(brush, "unnamed");
 345 }
 346
 347 float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 348 {
 349         float dist, bestdist;
 350         bestdist = DotProduct(points->v, normal);
 351         points++;
 352         while(--numpoints)
 353         {
 354                 dist = DotProduct(points->v, normal);
 355                 bestdist = min(bestdist, dist);
 356                 points++;
 357         }
 358         return bestdist;
 359 }
 360
 361 float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 362 {
 363         float dist, bestdist;
 364         bestdist = DotProduct(points->v, normal);
 365         points++;
 366         while(--numpoints)
 367         {
 368                 dist = DotProduct(points->v, normal);
 369                 bestdist = max(bestdist, dist);
 370                 points++;
 371         }
 372         return bestdist;
 373 }
 374
 375
 376 colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const mplane_t *originalplanes, int supercontents)
 377 {
 378         int j, k, m, w;
 379         int numpointsbuf = 0, maxpointsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
 380         colbrushf_t *brush;
 381         colpointf_t pointsbuf[256];
 382         colplanef_t planesbuf[256];
 383         int elementsbuf[1024];
 384         int polypointbuf[256];
 385         int pmaxpoints = 64;
 386         int pnumpoints;
 387         double p[2][3*64];
 388 #if 0
 389         // enable these if debugging to avoid seeing garbage in unused data
 390         memset(pointsbuf, 0, sizeof(pointsbuf));
 391         memset(planesbuf, 0, sizeof(planesbuf));
 392         memset(elementsbuf, 0, sizeof(elementsbuf));
 393         memset(polypointbuf, 0, sizeof(polypointbuf));
 394         memset(p, 0, sizeof(p));
 395 #endif
 396         // construct a collision brush (points, planes, and renderable mesh) from
 397         // a set of planes, this also optimizes out any unnecessary planes (ones
 398         // whose polygon is clipped away by the other planes)
 399         for (j = 0;j < numoriginalplanes;j++)
 400         {
 401                 // add the plane uniquely (no duplicates)
 402                 for (k = 0;k < numplanesbuf;k++)
 403                         if (VectorCompare(planesbuf[k].normal, originalplanes[j].normal) && planesbuf[k].dist == originalplanes[j].dist)
 404                                 break;
 405                 // if the plane is a duplicate, skip it
 406                 if (k < numplanesbuf)
 407                         continue;
 408                 // check if there are too many and skip the brush
 409                 if (numplanesbuf >= maxplanesbuf)
 410                 {
 411                         Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
 412                         return NULL;
 413                 }
 414
 415                 // create a large polygon from the plane
 416                 w = 0;
 417                 PolygonD_QuadForPlane(p[w], originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist, 1024.0*1024.0*1024.0);
 418                 pnumpoints = 4;
 419                 // clip it by all other planes
 420                 for (k = 0;k < numoriginalplanes && pnumpoints && pnumpoints <= pmaxpoints;k++)
 421                 {
 422                         if (k != j)
 423                         {
 424                                 // we want to keep the inside of the brush plane so we flip
 425                                 // the cutting plane
 426                                 PolygonD_Divide(pnumpoints, p[w], -originalplanes[k].normal[0], -originalplanes[k].normal[1], -originalplanes[k].normal[2], -originalplanes[k].dist, 1.0/32.0, pmaxpoints, p[!w], &pnumpoints, 0, NULL, NULL);
 427                                 w = !w;
 428                         }
 429                 }
 430                 // if nothing is left, skip it
 431                 if (pnumpoints < 3)
 432                 {
 433                         //Con_Printf("Collision_NewBrushFromPlanes: warning: polygon for plane %f %f %f %f clipped away\n", originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist);
 434                         continue;
 435                 }
 436
 437                 for (k = 0;k < pnumpoints;k++)
 438                 {
 439                         int l, m;
 440                         m = 0;
 441                         for (l = 0;l < numoriginalplanes;l++)
 442                                 if (fabs(DotProduct(&p[w][k*3], originalplanes[l].normal) - originalplanes[l].dist) < 1.0/8.0)
 443                                         m++;
 444                         if (m < 3)
 445                                 break;
 446                 }
 447                 if (k < pnumpoints)
 448                 {
 449                         Con_Printf("Collision_NewBrushFromPlanes: warning: polygon point does not lie on at least 3 planes\n");
 450                         //return NULL;
 451                 }
 452
 453                 // check if there are too many polygon vertices for buffer
 454                 if (pnumpoints > pmaxpoints)
 455                 {
 456                         Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 457                         return NULL;
 458                 }
 459
 460                 // check if there are too many triangle elements for buffer
 461                 if (numelementsbuf + (pnumpoints - 2) * 3 > maxelementsbuf)
 462                 {
 463                         Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
 464                         return NULL;
 465                 }
 466
 467                 for (k = 0;k < pnumpoints;k++)
 468                 {
 469                         // check if there is already a matching point (no duplicates)
 470                         for (m = 0;m < numpointsbuf;m++)
 471                                 if (VectorDistance2(&p[w][k*3], pointsbuf[m].v) < COLLISION_SNAP)
 472                                         break;
 473
 474                         // if there is no match, add a new one
 475                         if (m == numpointsbuf)
 476                         {
 477                                 // check if there are too many and skip the brush
 478                                 if (numpointsbuf >= maxpointsbuf)
 479                                 {
 480                                         Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 481                                         return NULL;
 482                                 }
 483                                 // add the new one
 484                                 VectorCopy(&p[w][k*3], pointsbuf[numpointsbuf].v);
 485                                 numpointsbuf++;
 486                         }
 487
 488                         // store the index into a buffer
 489                         polypointbuf[k] = m;
 490                 }
 491
 492                 // add the triangles for the polygon
 493                 // (this particular code makes a triangle fan)
 494                 for (k = 0;k < pnumpoints - 2;k++)
 495                 {
 496                         elementsbuf[numelementsbuf++] = polypointbuf[0];
 497                         elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
 498                         elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
 499                 }
 500
 501                 // add the new plane
 502                 VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
 503                 planesbuf[numplanesbuf].dist = originalplanes[j].dist;
 504                 numplanesbuf++;
 505         }
 506
 507         // validate plane distances
 508         for (j = 0;j < numplanesbuf;j++)
 509         {
 510                 float d = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpointsbuf);
 511                 if (fabs(planesbuf[j].dist - d) > (1.0f/32.0f))
 512                         Con_Printf("plane %f %f %f %f mismatches dist %f\n", planesbuf[j].normal[0], planesbuf[j].normal[1], planesbuf[j].normal[2], planesbuf[j].dist, d);
 513         }
 514
 515         // if nothing is left, there's nothing to allocate
 516         if (numelementsbuf < 12 || numplanesbuf < 4 || numpointsbuf < 4)
 517         {
 518                 Con_Printf("Collision_NewBrushFromPlanes: failed to build collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
 519                 return NULL;
 520         }
 521
 522         // allocate the brush and copy to it
 523         brush = Collision_AllocBrushFloat(mempool, numpointsbuf, numplanesbuf, numelementsbuf / 3, supercontents);
 524         for (j = 0;j < brush->numpoints;j++)
 525         {
 526                 brush->points[j].v[0] = pointsbuf[j].v[0];
 527                 brush->points[j].v[1] = pointsbuf[j].v[1];
 528                 brush->points[j].v[2] = pointsbuf[j].v[2];
 529         }
 530         for (j = 0;j < brush->numplanes;j++)
 531         {
 532                 brush->planes[j].normal[0] = planesbuf[j].normal[0];
 533                 brush->planes[j].normal[1] = planesbuf[j].normal[1];
 534                 brush->planes[j].normal[2] = planesbuf[j].normal[2];
 535                 brush->planes[j].dist = planesbuf[j].dist;
 536         }
 537         for (j = 0;j < brush->numtriangles * 3;j++)
 538                 brush->elements[j] = elementsbuf[j];
 539         VectorCopy(brush->points[0].v, brush->mins);
 540         VectorCopy(brush->points[0].v, brush->maxs);
 541         for (j = 1;j < brush->numpoints;j++)
 542         {
 543                 brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
 544                 brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
 545                 brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
 546                 brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
 547                 brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
 548                 brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
 549         }
 550         brush->mins[0] -= 1;
 551         brush->mins[1] -= 1;
 552         brush->mins[2] -= 1;
 553         brush->maxs[0] += 1;
 554         brush->maxs[1] += 1;
 555         brush->maxs[2] += 1;
 556         Collision_ValidateBrush(brush);
 557         return brush;
 558 }
 559
 560
 561
 562 colbrushf_t *Collision_AllocBrushFloat(mempool_t *mempool, int numpoints, int numplanes, int numtriangles, int supercontents)
 563 {
 564         colbrushf_t *brush;
 565         brush = Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpoints + sizeof(colplanef_t) * numplanes + sizeof(int[3]) * numtriangles);
 566         brush->supercontents = supercontents;
 567         brush->numplanes = numplanes;
 568         brush->numpoints = numpoints;
 569         brush->numtriangles = numtriangles;
 570         brush->planes = (void *)(brush + 1);
 571         brush->points = (void *)(brush->planes + brush->numplanes);
 572         brush->elements = (void *)(brush->points + brush->numpoints);
 573         return brush;
 574 }
 575
 576 void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
 577 {
 578         int i;
 579         float edge0[3], edge1[3], edge2[3], normal[3], dist, bestdist;
 580         colpointf_t *p, *p2;
 581
 582         // FIXME: these probably don't actually need to be normalized if the collision code does not care
 583         if (brush->numpoints == 3)
 584         {
 585                 // optimized triangle case
 586                 TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
 587                 if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
 588                 {
 589                         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 590                         brush->numplanes = 0;
 591                         return;
 592                 }
 593                 else
 594                 {
 595                         brush->numplanes = 5;
 596                         VectorNormalize(brush->planes[0].normal);
 597                         brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
 598                         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 599                         brush->planes[1].dist = -brush->planes[0].dist;
 600                         VectorSubtract(brush->points[2].v, brush->points[0].v, edge0);
 601                         VectorSubtract(brush->points[0].v, brush->points[1].v, edge1);
 602                         VectorSubtract(brush->points[1].v, brush->points[2].v, edge2);
 603 #if 1
 604                         {
 605                                 float projectionnormal[3], projectionedge0[3], projectionedge1[3], projectionedge2[3];
 606                                 int i, best;
 607                                 float dist, bestdist;
 608                                 bestdist = fabs(brush->planes[0].normal[0]);
 609                                 best = 0;
 610                                 for (i = 1;i < 3;i++)
 611                                 {
 612                                         dist = fabs(brush->planes[0].normal[i]);
 613                                         if (bestdist < dist)
 614                                         {
 615                                                 bestdist = dist;
 616                                                 best = i;
 617                                         }
 618                                 }
 619                                 VectorClear(projectionnormal);
 620                                 if (brush->planes[0].normal[best] < 0)
 621                                         projectionnormal[best] = -1;
 622                                 else
 623                                         projectionnormal[best] = 1;
 624                                 VectorCopy(edge0, projectionedge0);
 625                                 VectorCopy(edge1, projectionedge1);
 626                                 VectorCopy(edge2, projectionedge2);
 627                                 projectionedge0[best] = 0;
 628                                 projectionedge1[best] = 0;
 629                                 projectionedge2[best] = 0;
 630                                 CrossProduct(projectionedge0, projectionnormal, brush->planes[2].normal);
 631                                 CrossProduct(projectionedge1, projectionnormal, brush->planes[3].normal);
 632                                 CrossProduct(projectionedge2, projectionnormal, brush->planes[4].normal);
 633                         }
 634 #else
 635                         CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 636                         CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 637                         CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 638 #endif
 639                         VectorNormalize(brush->planes[2].normal);
 640                         VectorNormalize(brush->planes[3].normal);
 641                         VectorNormalize(brush->planes[4].normal);
 642                         brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
 643                         brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
 644                         brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
 645
 646                         if (developer.integer)
 647                         {
 648                                 // validation code
 649 #if 0
 650                                 float temp[3];
 651
 652                                 VectorSubtract(brush->points[0].v, brush->points[1].v, edge0);
 653                                 VectorSubtract(brush->points[2].v, brush->points[1].v, edge1);
 654                                 CrossProduct(edge0, edge1, normal);
 655                                 VectorNormalize(normal);
 656                                 VectorSubtract(normal, brush->planes[0].normal, temp);
 657                                 if (VectorLength(temp) > 0.01f)
 658                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: TriangleNormal gave wrong answer (%f %f %f != correct answer %f %f %f)\n", brush->planes->normal[0], brush->planes->normal[1], brush->planes->normal[2], normal[0], normal[1], normal[2]);
 659                                 if (fabs(DotProduct(brush->planes[1].normal, brush->planes[0].normal) - -1.0f) > 0.01f || fabs(brush->planes[1].dist - -brush->planes[0].dist) > 0.01f)
 660                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 1 (%f %f %f %f) is not opposite plane 0 (%f %f %f %f)\n", brush->planes[1].normal[0], brush->planes[1].normal[1], brush->planes[1].normal[2], brush->planes[1].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[0].dist);
 661 #if 0
 662                                 if (fabs(DotProduct(brush->planes[2].normal, brush->planes[0].normal)) > 0.01f)
 663                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 2 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[2].dist);
 664                                 if (fabs(DotProduct(brush->planes[3].normal, brush->planes[0].normal)) > 0.01f)
 665                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 3 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[3].dist);
 666                                 if (fabs(DotProduct(brush->planes[4].normal, brush->planes[0].normal)) > 0.01f)
 667                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 4 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[4].dist);
 668                                 if (fabs(DotProduct(brush->planes[2].normal, edge0)) > 0.01f)
 669                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 2 (%f %f %f %f) is not perpendicular to edge 0 (%f %f %f to %f %f %f)\n", brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist, brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2]);
 670                                 if (fabs(DotProduct(brush->planes[3].normal, edge1)) > 0.01f)
 671                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 3 (%f %f %f %f) is not perpendicular to edge 1 (%f %f %f to %f %f %f)\n", brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist, brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2]);
 672                                 if (fabs(DotProduct(brush->planes[4].normal, edge2)) > 0.01f)
 673                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 4 (%f %f %f %f) is not perpendicular to edge 2 (%f %f %f to %f %f %f)\n", brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist, brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2]);
 674 #endif
 675 #endif
 676                                 if (fabs(DotProduct(brush->points[0].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f)
 677                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edges (%f %f %f to %f %f %f to %f %f %f) off front plane 0 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[0].dist);
 678                                 if (fabs(DotProduct(brush->points[0].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f)
 679                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edges (%f %f %f to %f %f %f to %f %f %f) off back plane 1 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[1].normal[0], brush->planes[1].normal[1], brush->planes[1].normal[2], brush->planes[1].dist);
 680                                 if (fabs(DotProduct(brush->points[2].v, brush->planes[2].normal) - brush->planes[2].dist) > 0.01f || fabs(DotProduct(brush->points[0].v, brush->planes[2].normal) - brush->planes[2].dist) > 0.01f)
 681                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist);
 682                                 if (fabs(DotProduct(brush->points[0].v, brush->planes[3].normal) - brush->planes[3].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[3].normal) - brush->planes[3].dist) > 0.01f)
 683                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist);
 684                                 if (fabs(DotProduct(brush->points[1].v, brush->planes[4].normal) - brush->planes[4].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[4].normal) - brush->planes[4].dist) > 0.01f)
 685                                         Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist);
 686                         }
 687                 }
 688         }
 689         else
 690         {
 691                 // choose best surface normal for polygon's plane
 692                 bestdist = 0;
 693                 for (i = 0, p = brush->points + 1;i < brush->numpoints - 2;i++, p++)
 694                 {
 695                         VectorSubtract(p[-1].v, p[0].v, edge0);
 696                         VectorSubtract(p[1].v, p[0].v, edge1);
 697                         CrossProduct(edge0, edge1, normal);
 698                         //TriangleNormal(p[-1].v, p[0].v, p[1].v, normal);
 699                         dist = DotProduct(normal, normal);
 700                         if (i == 0 || bestdist < dist)
 701                         {
 702                                 bestdist = dist;
 703                                 VectorCopy(normal, brush->planes->normal);
 704                         }
 705                 }
 706                 if (bestdist < 0.0001f)
 707                 {
 708                         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 709                         brush->numplanes = 0;
 710                         return;
 711                 }
 712                 else
 713                 {
 714                         brush->numplanes = brush->numpoints + 2;
 715                         VectorNormalize(brush->planes->normal);
 716                         brush->planes->dist = DotProduct(brush->points->v, brush->planes->normal);
 717
 718                         // negate plane to create other side
 719                         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 720                         brush->planes[1].dist = -brush->planes[0].dist;
 721                         for (i = 0, p = brush->points + (brush->numpoints - 1), p2 = brush->points;i < brush->numpoints;i++, p = p2, p2++)
 722                         {
 723                                 VectorSubtract(p->v, p2->v, edge0);
 724                                 CrossProduct(edge0, brush->planes->normal, brush->planes[i + 2].normal);
 725                                 VectorNormalize(brush->planes[i + 2].normal);
 726                                 brush->planes[i + 2].dist = DotProduct(p->v, brush->planes[i + 2].normal);
 727                         }
 728                 }
 729         }
 730
 731         if (developer.integer)
 732         {
 733                 // validity check - will be disabled later
 734                 Collision_ValidateBrush(brush);
 735                 for (i = 0;i < brush->numplanes;i++)
 736                 {
 737                         int j;
 738                         for (j = 0, p = brush->points;j < brush->numpoints;j++, p++)
 739                                 if (DotProduct(p->v, brush->planes[i].normal) > brush->planes[i].dist + (1.0 / 32.0))
 740                                         Con_Printf("Error in brush plane generation, plane %i\n", i);
 741                 }
 742         }
 743 }
 744
 745 colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents)
 746 {
 747         colbrushf_t *brush;
 748         brush = Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2));
 749         brush->supercontents = supercontents;
 750         brush->numpoints = numpoints;
 751         brush->numplanes = numpoints + 2;
 752         brush->planes = (void *)(brush + 1);
 753         brush->points = (colpointf_t *)points;
 754         Host_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...\n");
 755         return brush;
 756 }
 757
 758 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 759 void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 760 {
 761         int nplane, nplane2, fstartsolid, fendsolid, brushsolid;
 762         float enterfrac, leavefrac, d1, d2, f, imove, newimpactnormal[3], enterfrac2;
 763         const colplanef_t *startplane, *endplane;
 764
 765         enterfrac = -1;
 766         enterfrac2 = -1;
 767         leavefrac = 1;
 768         fstartsolid = true;
 769         fendsolid = true;
 770
 771         for (nplane = 0;nplane < thatbrush_start->numplanes + thisbrush_start->numplanes;nplane++)
 772         {
 773                 nplane2 = nplane;
 774                 if (nplane2 >= thatbrush_start->numplanes)
 775                 {
 776                         nplane2 -= thatbrush_start->numplanes;
 777                         startplane = thisbrush_start->planes + nplane2;
 778                         endplane = thisbrush_end->planes + nplane2;
 779                         if (developer.integer)
 780                         {
 781                                 // any brush with degenerate planes is not worth handling
 782                                 if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 783                                 {
 784                                         Con_Print("Collision_TraceBrushBrushFloat: degenerate thisbrush plane!\n");
 785                                         return;
 786                                 }
 787                                 f = furthestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints);
 788                                 if (fabs(f - startplane->dist) > 0.125f)
 789                                         Con_Printf("startplane->dist %f != calculated %f (thisbrush_start)\n", startplane->dist, f);
 790                         }
 791                         d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints) - collision_startnudge.value;
 792                         d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints) - collision_endnudge.value;
 793                 }
 794                 else
 795                 {
 796                         startplane = thatbrush_start->planes + nplane2;
 797                         endplane = thatbrush_end->planes + nplane2;
 798                         if (developer.integer)
 799                         {
 800                                 // any brush with degenerate planes is not worth handling
 801                                 if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 802                                 {
 803                                         Con_Print("Collision_TraceBrushBrushFloat: degenerate thatbrush plane!\n");
 804                                         return;
 805                                 }
 806                                 f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
 807                                 if (fabs(f - startplane->dist) > 0.125f)
 808                                         Con_Printf("startplane->dist %f != calculated %f (thatbrush_start)\n", startplane->dist, f);
 809                         }
 810                         d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - startplane->dist - collision_startnudge.value;
 811                         d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - endplane->dist - collision_endnudge.value;
 812                 }
 813                 //Con_Printf("%c%i: d1 = %f, d2 = %f, d1 / (d1 - d2) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, d1, d2, d1 / (d1 - d2));
 814
 815                 if(d1 > d2)
 816                 {
 817                         // moving into brush
 818                         if(d2 > 0)
 819                                 return;
 820                         if(d1 > 0)
 821                         {
 822                                 // enter
 823                                 fstartsolid = false;
 824                                 imove = 1 / (d1 - d2);
 825                                 f = (d1 - collision_enternudge.value) * imove;
 826                                 if (enterfrac < f)
 827                                 {
 828                                         enterfrac = f;
 829                                         enterfrac2 = f - collision_impactnudge.value * imove;
 830                                         VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
 831                                 }
 832                         }
 833                 }
 834                 else
 835                 {
 836                         // moving out of brush
 837                         if(d1 > 0)
 838                                 return;
 839                         if(d2 > 0)
 840                         {
 841                                 // leave
 842                                 fendsolid = false;
 843                                 f = (d1 + collision_leavenudge.value) / (d1 - d2);
 844                                 if (leavefrac > f)
 845                                         leavefrac = f;
 846                         }
 847                 }
 848         }
 849
 850         brushsolid = trace->hitsupercontentsmask & thatbrush_start->supercontents;
 851         if (fstartsolid)
 852         {
 853                 trace->startsupercontents |= thatbrush_start->supercontents;
 854                 if (brushsolid)
 855                 {
 856                         trace->startsolid = true;
 857                         if (fendsolid)
 858                                 trace->allsolid = true;
 859                 }
 860         }
 861
 862         // LordHavoc: we need an epsilon nudge here because for a point trace the
 863         // penetrating line segment is normally zero length if this brush was
 864         // generated from a polygon (infinitely thin), and could even be slightly
 865         // positive or negative due to rounding errors in that case.
 866         if (brushsolid && enterfrac > -1 && enterfrac < trace->realfraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
 867         {
 868 #if 0
 869                 // broken
 870                 if (thatbrush_start->ispolygon)
 871                 {
 872                         d1 = nearestplanedist_float(thatbrush_start->planes[0].normal, thisbrush_start->points, thisbrush_start->numpoints) - thatbrush_start->planes[0].dist - collision_startnudge.value;
 873                         d2 = nearestplanedist_float(thatbrush_end->planes[0].normal, thisbrush_end->points, thisbrush_end->numpoints) - thatbrush_end->planes[0].dist - collision_endnudge.value;
 874                         move = d1 - d2;
 875                         if (move <= 0 || d2 > collision_enternudge.value || d1 < 0)
 876                                 return;
 877                         // enter
 878                         imove = 1 / move;
 879                         enterfrac = (d1 - collision_enternudge.value) * imove;
 880                         if (enterfrac < trace->realfraction)
 881                         {
 882                                 enterfrac2 = enterfrac - collision_impactnudge.value * imove;
 883                                 trace->realfraction = bound(0, enterfrac, 1);
 884                                 trace->fraction = bound(0, enterfrac2, 1);
 885                                 VectorLerp(thatbrush_start->planes[0].normal, enterfrac, thatbrush_end->planes[0].normal, trace->plane.normal);
 886                         }
 887                 }
 888                 else
 889 #endif
 890                 {
 891                         trace->realfraction = bound(0, enterfrac, 1);
 892                         trace->fraction = bound(0, enterfrac2, 1);
 893                         VectorCopy(newimpactnormal, trace->plane.normal);
 894                 }
 895         }
 896 }
 897
 898 // NOTE: start and end brush pair must have same numplanes/numpoints
 899 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 900 {
 901         int nplane, fstartsolid, fendsolid, brushsolid;
 902         float enterfrac, leavefrac, d1, d2, f, imove, newimpactnormal[3], enterfrac2;
 903         const colplanef_t *startplane, *endplane;
 904
 905         enterfrac = -1;
 906         enterfrac2 = -1;
 907         leavefrac = 1;
 908         fstartsolid = true;
 909         fendsolid = true;
 910
 911         for (nplane = 0;nplane < thatbrush_start->numplanes;nplane++)
 912         {
 913                 startplane = thatbrush_start->planes + nplane;
 914                 endplane = thatbrush_end->planes + nplane;
 915                 d1 = DotProduct(startplane->normal, linestart) - startplane->dist - collision_startnudge.value;
 916                 d2 = DotProduct(endplane->normal, lineend) - endplane->dist - collision_endnudge.value;
 917                 if (developer.integer)
 918                 {
 919                         // any brush with degenerate planes is not worth handling
 920                         if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 921                         {
 922                                 Con_Print("Collision_TraceLineBrushFloat: degenerate plane!\n");
 923                                 return;
 924                         }
 925                         if (thatbrush_start->numpoints)
 926                         {
 927                                 f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
 928                                 if (fabs(f - startplane->dist) > 0.125f)
 929                                         Con_Printf("startplane->dist %f != calculated %f\n", startplane->dist, f);
 930                         }
 931                 }
 932
 933                 if (d1 > d2)
 934                 {
 935                         // moving into brush
 936                         if (d2 > 0)
 937                                 return;
 938                         if (d1 > 0)
 939                         {
 940                                 // enter
 941                                 fstartsolid = false;
 942                                 imove = 1 / (d1 - d2);
 943                                 f = (d1 - collision_enternudge.value) * imove;
 944                                 if (enterfrac < f)
 945                                 {
 946                                         enterfrac = f;
 947                                         enterfrac2 = f - collision_impactnudge.value * imove;
 948                                         VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
 949                                 }
 950                         }
 951                 }
 952                 else
 953                 {
 954                         // moving out of brush
 955                         if (d1 > 0)
 956                                 return;
 957                         if (d2 > 0)
 958                         {
 959                                 // leave
 960                                 fendsolid = false;
 961                                 f = (d1 + collision_leavenudge.value) / (d1 - d2);
 962                                 if (leavefrac > f)
 963                                         leavefrac = f;
 964                         }
 965                 }
 966         }
 967
 968         brushsolid = trace->hitsupercontentsmask & thatbrush_start->supercontents;
 969         if (fstartsolid)
 970         {
 971                 trace->startsupercontents |= thatbrush_start->supercontents;
 972                 if (brushsolid)
 973                 {
 974                         trace->startsolid = true;
 975                         if (fendsolid)
 976                                 trace->allsolid = true;
 977                 }
 978         }
 979
 980         // LordHavoc: we need an epsilon nudge here because for a point trace the
 981         // penetrating line segment is normally zero length if this brush was
 982         // generated from a polygon (infinitely thin), and could even be slightly
 983         // positive or negative due to rounding errors in that case.
 984         if (brushsolid && enterfrac > -1 && enterfrac < trace->realfraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
 985         {
 986 #if 0
 987                 // broken
 988                 if (thatbrush_start->ispolygon)
 989                 {
 990                         d1 = DotProduct(thatbrush_start->planes[0].normal, linestart) - thatbrush_start->planes[0].dist - collision_startnudge.value;
 991                         d2 = DotProduct(thatbrush_end->planes[0].normal, lineend) - thatbrush_end->planes[0].dist - collision_endnudge.value;
 992                         move = d1 - d2;
 993                         if (move <= 0 || d2 > collision_enternudge.value || d1 < 0)
 994                                 return;
 995                         // enter
 996                         imove = 1 / move;
 997                         enterfrac = (d1 - collision_enternudge.value) * imove;
 998                         if (enterfrac < trace->realfraction)
 999                         {
1000                                 enterfrac2 = enterfrac - collision_impactnudge.value * imove;
1001                                 trace->realfraction = bound(0, enterfrac, 1);
1002                                 trace->fraction = bound(0, enterfrac2, 1);
1003                                 VectorLerp(thatbrush_start->planes[0].normal, enterfrac, thatbrush_end->planes[0].normal, trace->plane.normal);
1004                         }
1005                 }
1006                 else
1007 #endif
1008                 {
1009                         trace->realfraction = bound(0, enterfrac, 1);
1010                         trace->fraction = bound(0, enterfrac2, 1);
1011                         VectorCopy(newimpactnormal, trace->plane.normal);
1012                 }
1013         }
1014 }
1015
1016 void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
1017 {
1018         int nplane;
1019         const colplanef_t *plane;
1020
1021         for (nplane = 0, plane = thatbrush->planes;nplane < thatbrush->numplanes;nplane++, plane++)
1022                 if (DotProduct(plane->normal, point) > plane->dist)
1023                         return;
1024
1025         trace->startsupercontents |= thatbrush->supercontents;
1026         if (trace->hitsupercontentsmask & thatbrush->supercontents)
1027         {
1028                 trace->startsolid = true;
1029                 trace->allsolid = true;
1030         }
1031 }
1032
1033 static colpointf_t polyf_points[256];
1034 static colplanef_t polyf_planes[256 + 2];
1035 static colbrushf_t polyf_brush;
1036
1037 void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
1038 {
1039         while (numpoints--)
1040         {
1041                 out->v[0] = floor(in->v[0] * fractionprecision + 0.5f) * invfractionprecision;
1042                 out->v[1] = floor(in->v[1] * fractionprecision + 0.5f) * invfractionprecision;
1043                 out->v[2] = floor(in->v[2] * fractionprecision + 0.5f) * invfractionprecision;
1044         }
1045 }
1046
1047 void Collision_TraceBrushPolygonFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numpoints, const float *points, int supercontents)
1048 {
1049         if (numpoints > 256)
1050         {
1051                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
1052                 return;
1053         }
1054         polyf_brush.numpoints = numpoints;
1055         polyf_brush.numplanes = numpoints + 2;
1056         //polyf_brush.points = (colpointf_t *)points;
1057         polyf_brush.planes = polyf_planes;
1058         polyf_brush.supercontents = supercontents;
1059         polyf_brush.points = polyf_points;
1060         Collision_SnapCopyPoints(numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1061         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
1062         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
1063         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brush, &polyf_brush);
1064 }
1065
1066 void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numtriangles, const int *element3i, const float *vertex3f, int supercontents, const vec3_t segmentmins, const vec3_t segmentmaxs)
1067 {
1068         int i;
1069         float facemins[3], facemaxs[3];
1070         polyf_brush.numpoints = 3;
1071         polyf_brush.numplanes = 5;
1072         polyf_brush.points = polyf_points;
1073         polyf_brush.planes = polyf_planes;
1074         polyf_brush.supercontents = supercontents;
1075         for (i = 0;i < numtriangles;i++, element3i += 3)
1076         {
1077                 VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
1078                 VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
1079                 VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
1080                 Collision_SnapCopyPoints(3, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1081                 facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0])) - 1;
1082                 facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1])) - 1;
1083                 facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2])) - 1;
1084                 facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0])) + 1;
1085                 facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1])) + 1;
1086                 facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2])) + 1;
1087                 if (BoxesOverlap(segmentmins, segmentmaxs, facemins, facemaxs))
1088                 {
1089                         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
1090                         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
1091                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brush, &polyf_brush);
1092                 }
1093         }
1094 }
1095
1096 void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numpoints, const float *points, int supercontents)
1097 {
1098         if (numpoints > 256)
1099         {
1100                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
1101                 return;
1102         }
1103         polyf_brush.numpoints = numpoints;
1104         polyf_brush.numplanes = numpoints + 2;
1105         //polyf_brush.points = (colpointf_t *)points;
1106         polyf_brush.points = polyf_points;
1107         Collision_SnapCopyPoints(numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1108         polyf_brush.planes = polyf_planes;
1109         polyf_brush.supercontents = supercontents;
1110         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
1111         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
1112         Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
1113 }
1114
1115 void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numtriangles, const int *element3i, const float *vertex3f, int supercontents, const vec3_t segmentmins, const vec3_t segmentmaxs)
1116 {
1117         int i;
1118 #if 1
1119         // FIXME: snap vertices?
1120         for (i = 0;i < numtriangles;i++, element3i += 3)
1121                 Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3);
1122 #else
1123         polyf_brush.numpoints = 3;
1124         polyf_brush.numplanes = 5;
1125         polyf_brush.points = polyf_points;
1126         polyf_brush.planes = polyf_planes;
1127         polyf_brush.supercontents = supercontents;
1128         for (i = 0;i < numtriangles;i++, element3i += 3)
1129         {
1130                 float facemins[3], facemaxs[3];
1131                 VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
1132                 VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
1133                 VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
1134                 Collision_SnapCopyPoints(numpoints, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1135                 facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0])) - 1;
1136                 facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1])) - 1;
1137                 facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2])) - 1;
1138                 facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0])) + 1;
1139                 facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1])) + 1;
1140                 facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2])) + 1;
1141                 if (BoxesOverlap(segmentmins, segmentmaxs, facemins, facemaxs))
1142                 {
1143                         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
1144                         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
1145                         Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
1146                 }
1147         }
1148 #endif
1149 }
1150
1151
1152 static colpointf_t polyf_pointsstart[256], polyf_pointsend[256];
1153 static colplanef_t polyf_planesstart[256 + 2], polyf_planesend[256 + 2];
1154 static colbrushf_t polyf_brushstart, polyf_brushend;
1155
1156 void Collision_TraceBrushPolygonTransformFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numpoints, const float *points, const matrix4x4_t *polygonmatrixstart, const matrix4x4_t *polygonmatrixend, int supercontents)
1157 {
1158         int i;
1159         if (numpoints > 256)
1160         {
1161                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
1162                 return;
1163         }
1164         polyf_brushstart.numpoints = numpoints;
1165         polyf_brushstart.numplanes = numpoints + 2;
1166         polyf_brushstart.points = polyf_pointsstart;//(colpointf_t *)points;
1167         polyf_brushstart.planes = polyf_planesstart;
1168         polyf_brushstart.supercontents = supercontents;
1169         for (i = 0;i < numpoints;i++)
1170                 Matrix4x4_Transform(polygonmatrixstart, points + i * 3, polyf_brushstart.points[i].v);
1171         polyf_brushend.numpoints = numpoints;
1172         polyf_brushend.numplanes = numpoints + 2;
1173         polyf_brushend.points = polyf_pointsend;//(colpointf_t *)points;
1174         polyf_brushend.planes = polyf_planesend;
1175         polyf_brushend.supercontents = supercontents;
1176         for (i = 0;i < numpoints;i++)
1177                 Matrix4x4_Transform(polygonmatrixend, points + i * 3, polyf_brushend.points[i].v);
1178         Collision_SnapCopyPoints(numpoints, polyf_pointsstart, polyf_pointsstart, COLLISION_SNAPSCALE, COLLISION_SNAP);
1179         Collision_SnapCopyPoints(numpoints, polyf_pointsend, polyf_pointsend, COLLISION_SNAPSCALE, COLLISION_SNAP);
1180         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushstart);
1181         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushend);
1182
1183         //Collision_PrintBrushAsQHull(&polyf_brushstart, "polyf_brushstart");
1184         //Collision_PrintBrushAsQHull(&polyf_brushend, "polyf_brushend");
1185
1186         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brushstart, &polyf_brushend);
1187 }
1188
1189
1190
1191 #define MAX_BRUSHFORBOX 16
1192 static int brushforbox_index = 0;
1193 static colpointf_t brushforbox_point[MAX_BRUSHFORBOX*8];
1194 static colplanef_t brushforbox_plane[MAX_BRUSHFORBOX*6];
1195 static colbrushf_t brushforbox_brush[MAX_BRUSHFORBOX];
1196 static colbrushf_t brushforpoint_brush[MAX_BRUSHFORBOX];
1197
1198 void Collision_InitBrushForBox(void)
1199 {
1200         int i;
1201         for (i = 0;i < MAX_BRUSHFORBOX;i++)
1202         {
1203                 brushforbox_brush[i].supercontents = SUPERCONTENTS_SOLID;
1204                 brushforbox_brush[i].numpoints = 8;
1205                 brushforbox_brush[i].numplanes = 6;
1206                 brushforbox_brush[i].points = brushforbox_point + i * 8;
1207                 brushforbox_brush[i].planes = brushforbox_plane + i * 6;
1208                 brushforpoint_brush[i].supercontents = SUPERCONTENTS_SOLID;
1209                 brushforpoint_brush[i].numpoints = 1;
1210                 brushforpoint_brush[i].numplanes = 0;
1211                 brushforpoint_brush[i].points = brushforbox_point + i * 8;
1212                 brushforpoint_brush[i].planes = brushforbox_plane + i * 6;
1213         }
1214 }
1215
1216 colbrushf_t *Collision_BrushForBox(const matrix4x4_t *matrix, const vec3_t mins, const vec3_t maxs)
1217 {
1218         int i, j;
1219         vec3_t v;
1220         colbrushf_t *brush;
1221         if (brushforbox_brush[0].numpoints == 0)
1222                 Collision_InitBrushForBox();
1223         // FIXME: these probably don't actually need to be normalized if the collision code does not care
1224         if (VectorCompare(mins, maxs))
1225         {
1226                 // point brush
1227                 brush = brushforpoint_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
1228                 VectorCopy(mins, brush->points->v);
1229         }
1230         else
1231         {
1232                 brush = brushforbox_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
1233                 // FIXME: optimize
1234                 for (i = 0;i < 8;i++)
1235                 {
1236                         v[0] = i & 1 ? maxs[0] : mins[0];
1237                         v[1] = i & 2 ? maxs[1] : mins[1];
1238                         v[2] = i & 4 ? maxs[2] : mins[2];
1239                         Matrix4x4_Transform(matrix, v, brush->points[i].v);
1240                 }
1241                 // FIXME: optimize!
1242                 for (i = 0;i < 6;i++)
1243                 {
1244                         VectorClear(v);
1245                         v[i >> 1] = i & 1 ? 1 : -1;
1246                         Matrix4x4_Transform3x3(matrix, v, brush->planes[i].normal);
1247                         VectorNormalize(brush->planes[i].normal);
1248                 }
1249         }
1250         for (j = 0;j < brush->numplanes;j++)
1251                 brush->planes[j].dist = furthestplanedist_float(brush->planes[j].normal, brush->points, brush->numpoints);
1252         VectorCopy(brush->points[0].v, brush->mins);
1253         VectorCopy(brush->points[0].v, brush->maxs);
1254         for (j = 1;j < brush->numpoints;j++)
1255         {
1256                 brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
1257                 brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
1258                 brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
1259                 brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
1260                 brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
1261                 brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
1262         }
1263         brush->mins[0] -= 1;
1264         brush->mins[1] -= 1;
1265         brush->mins[2] -= 1;
1266         brush->maxs[0] += 1;
1267         brush->maxs[1] += 1;
1268         brush->maxs[2] += 1;
1269         Collision_ValidateBrush(brush);
1270         return brush;
1271 }
1272
1273 void Collision_ClipTrace_BrushBox(trace_t *trace, const vec3_t cmins, const vec3_t cmaxs, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask)
1274 {
1275         colbrushf_t *boxbrush, *thisbrush_start, *thisbrush_end;
1276         matrix4x4_t identitymatrix;
1277         vec3_t startmins, startmaxs, endmins, endmaxs;
1278
1279         // create brushes for the collision
1280         VectorAdd(start, mins, startmins);
1281         VectorAdd(start, maxs, startmaxs);
1282         VectorAdd(end, mins, endmins);
1283         VectorAdd(end, maxs, endmaxs);
1284         Matrix4x4_CreateIdentity(&identitymatrix);
1285         boxbrush = Collision_BrushForBox(&identitymatrix, cmins, cmaxs);
1286         thisbrush_start = Collision_BrushForBox(&identitymatrix, startmins, startmaxs);
1287         thisbrush_end = Collision_BrushForBox(&identitymatrix, endmins, endmaxs);
1288
1289         memset(trace, 0, sizeof(trace_t));
1290         trace->hitsupercontentsmask = hitsupercontentsmask;
1291         trace->fraction = 1;
1292         trace->realfraction = 1;
1293         trace->allsolid = true;
1294         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, boxbrush, boxbrush);
1295 }
1296
1297 // LordHavoc: currently unused and not yet tested
1298 // note: this can be used for tracing a moving sphere vs a stationary sphere,
1299 // by simply adding the moving sphere's radius to the sphereradius parameter,
1300 // all the results are correct (impactpoint, impactnormal, and fraction)
1301 float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double *sphereorigin, double sphereradius, double *impactpoint, double *impactnormal)
1302 {
1303         double dir[3], scale, v[3], deviationdist, impactdist, linelength;
1304         // make sure the impactpoint and impactnormal are valid even if there is
1305         // no collision
1306         impactpoint[0] = lineend[0];
1307         impactpoint[1] = lineend[1];
1308         impactpoint[2] = lineend[2];
1309         impactnormal[0] = 0;
1310         impactnormal[1] = 0;
1311         impactnormal[2] = 0;
1312         // calculate line direction
1313         dir[0] = lineend[0] - linestart[0];
1314         dir[1] = lineend[1] - linestart[1];
1315         dir[2] = lineend[2] - linestart[2];
1316         // normalize direction
1317         linelength = sqrt(dir[0] * dir[0] + dir[1] * dir[1] + dir[2] * dir[2]);
1318         if (linelength)
1319         {
1320                 scale = 1.0 / linelength;
1321                 dir[0] *= scale;
1322                 dir[1] *= scale;
1323                 dir[2] *= scale;
1324         }
1325         // this dotproduct calculates the distance along the line at which the
1326         // sphere origin is (nearest point to the sphere origin on the line)
1327         impactdist = dir[0] * (sphereorigin[0] - linestart[0]) + dir[1] * (sphereorigin[1] - linestart[1]) + dir[2] * (sphereorigin[2] - linestart[2]);
1328         // calculate point on line at that distance, and subtract the
1329         // sphereorigin from it, so we have a vector to measure for the distance
1330         // of the line from the sphereorigin (deviation, how off-center it is)
1331         v[0] = linestart[0] + impactdist * dir[0] - sphereorigin[0];
1332         v[1] = linestart[1] + impactdist * dir[1] - sphereorigin[1];
1333         v[2] = linestart[2] + impactdist * dir[2] - sphereorigin[2];
1334         deviationdist = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
1335         // if outside the radius, it's a miss for sure
1336         // (we do this comparison using squared radius to avoid a sqrt)
1337         if (deviationdist > sphereradius*sphereradius)
1338                 return 1; // miss (off to the side)
1339         // nudge back to find the correct impact distance
1340         impactdist += (sqrt(deviationdist) - sphereradius);
1341         if (impactdist >= linelength)
1342                 return 1; // miss (not close enough)
1343         if (impactdist < 0)
1344                 return 1; // miss (linestart is past or inside sphere)
1345         // calculate new impactpoint
1346         impactpoint[0] = linestart[0] + impactdist * dir[0];
1347         impactpoint[1] = linestart[1] + impactdist * dir[1];
1348         impactpoint[2] = linestart[2] + impactdist * dir[2];
1349         // calculate impactnormal (surface normal at point of impact)
1350         impactnormal[0] = impactpoint[0] - sphereorigin[0];
1351         impactnormal[1] = impactpoint[1] - sphereorigin[1];
1352         impactnormal[2] = impactpoint[2] - sphereorigin[2];
1353         // normalize impactnormal
1354         scale = impactnormal[0] * impactnormal[0] + impactnormal[1] * impactnormal[1] + impactnormal[2] * impactnormal[2];
1355         if (scale)
1356         {
1357                 scale = 1.0 / sqrt(scale);
1358                 impactnormal[0] *= scale;
1359                 impactnormal[1] *= scale;
1360                 impactnormal[2] *= scale;
1361         }
1362         // return fraction of movement distance
1363         return impactdist / linelength;
1364 }
1365
1366 void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const float *point0, const float *point1, const float *point2)
1367 {
1368 #if 1
1369         // more optimized
1370         float d1, d2, d, f, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
1371
1372         // this function executes:
1373         // 32 ops when line starts behind triangle
1374         // 38 ops when line ends infront of triangle
1375         // 43 ops when line fraction is already closer than this triangle
1376         // 72 ops when line is outside edge 01
1377         // 92 ops when line is outside edge 21
1378         // 115 ops when line is outside edge 02
1379         // 123 ops when line impacts triangle and updates trace results
1380
1381         // this code is designed for clockwise triangles, conversion to
1382         // counterclockwise would require swapping some things around...
1383         // it is easier to simply swap the point0 and point2 parameters to this
1384         // function when calling it than it is to rewire the internals.
1385
1386         // calculate the faceplanenormal of the triangle, this represents the front side
1387         // 15 ops
1388         VectorSubtract(point0, point1, edge01);
1389         VectorSubtract(point2, point1, edge21);
1390         CrossProduct(edge01, edge21, faceplanenormal);
1391         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
1392         // 6 ops
1393         faceplanenormallength2 = DotProduct(faceplanenormal, faceplanenormal);
1394         if (faceplanenormallength2 < 0.0001f)
1395                 return;
1396         // calculate the distance
1397         // 5 ops
1398         faceplanedist = DotProduct(point0, faceplanenormal);
1399
1400         // if start point is on the back side there is no collision
1401         // (we don't care about traces going through the triangle the wrong way)
1402
1403         // calculate the start distance
1404         // 6 ops
1405         d1 = DotProduct(faceplanenormal, linestart);
1406         if (d1 <= faceplanedist)
1407                 return;
1408
1409         // calculate the end distance
1410         // 6 ops
1411         d2 = DotProduct(faceplanenormal, lineend);
1412         // if both are in front, there is no collision
1413         if (d2 >= faceplanedist)
1414                 return;
1415
1416         // from here on we know d1 is >= 0 and d2 is < 0
1417         // this means the line starts infront and ends behind, passing through it
1418
1419         // calculate the recipricol of the distance delta,
1420         // so we can use it multiple times cheaply (instead of division)
1421         // 2 ops
1422         d = 1.0f / (d1 - d2);
1423         // calculate the impact fraction by taking the start distance (> 0)
1424         // and subtracting the face plane distance (this is the distance of the
1425         // triangle along that same normal)
1426         // then multiply by the recipricol distance delta
1427         // 2 ops
1428         f = (d1 - faceplanedist) * d;
1429         // skip out if this impact is further away than previous ones
1430         // 1 ops
1431         if (f > trace->realfraction)
1432                 return;
1433         // calculate the perfect impact point for classification of insidedness
1434         // 9 ops
1435         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1436         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1437         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1438
1439         // calculate the edge normal and reject if impact is outside triangle
1440         // (an edge normal faces away from the triangle, to get the desired normal
1441         //  a crossproduct with the faceplanenormal is used, and because of the way
1442         // the insidedness comparison is written it does not need to be normalized)
1443
1444         // first use the two edges from the triangle plane math
1445         // the other edge only gets calculated if the point survives that long
1446
1447         // 20 ops
1448         CrossProduct(edge01, faceplanenormal, edgenormal);
1449         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1450                 return;
1451
1452         // 20 ops
1453         CrossProduct(faceplanenormal, edge21, edgenormal);
1454         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1455                 return;
1456
1457         // 23 ops
1458         VectorSubtract(point0, point2, edge02);
1459         CrossProduct(faceplanenormal, edge02, edgenormal);
1460         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1461                 return;
1462
1463         // 8 ops (rare)
1464
1465         // store the new trace fraction
1466         trace->realfraction = f;
1467
1468         // calculate a nudged fraction to keep it out of the surface
1469         // (the main fraction remains perfect)
1470         trace->fraction = f - collision_impactnudge.value * d;
1471
1472         // store the new trace plane (because collisions only happen from
1473         // the front this is always simply the triangle normal, never flipped)
1474         d = 1.0 / sqrt(faceplanenormallength2);
1475         VectorScale(faceplanenormal, d, trace->plane.normal);
1476         trace->plane.dist = faceplanedist * d;
1477 #else
1478         float d1, d2, d, f, fnudged, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, edge[3];
1479
1480         // this code is designed for clockwise triangles, conversion to
1481         // counterclockwise would require swapping some things around...
1482         // it is easier to simply swap the point0 and point2 parameters to this
1483         // function when calling it than it is to rewire the internals.
1484
1485         // calculate the unnormalized faceplanenormal of the triangle,
1486         // this represents the front side
1487         TriangleNormal(point0, point1, point2, faceplanenormal);
1488         // there's no point in processing a degenerate triangle
1489         // (GIGO - Garbage In, Garbage Out)
1490         if (DotProduct(faceplanenormal, faceplanenormal) < 0.0001f)
1491                 return;
1492         // calculate the unnormalized distance
1493         faceplanedist = DotProduct(point0, faceplanenormal);
1494
1495         // calculate the unnormalized start distance
1496         d1 = DotProduct(faceplanenormal, linestart) - faceplanedist;
1497         // if start point is on the back side there is no collision
1498         // (we don't care about traces going through the triangle the wrong way)
1499         if (d1 <= 0)
1500                 return;
1501
1502         // calculate the unnormalized end distance
1503         d2 = DotProduct(faceplanenormal, lineend) - faceplanedist;
1504         // if both are in front, there is no collision
1505         if (d2 >= 0)
1506                 return;
1507
1508         // from here on we know d1 is >= 0 and d2 is < 0
1509         // this means the line starts infront and ends behind, passing through it
1510
1511         // calculate the recipricol of the distance delta,
1512         // so we can use it multiple times cheaply (instead of division)
1513         d = 1.0f / (d1 - d2);
1514         // calculate the impact fraction by taking the start distance (> 0)
1515         // and subtracting the face plane distance (this is the distance of the
1516         // triangle along that same normal)
1517         // then multiply by the recipricol distance delta
1518         f = d1 * d;
1519         // skip out if this impact is further away than previous ones
1520         if (f > trace->realfraction)
1521                 return;
1522         // calculate the perfect impact point for classification of insidedness
1523         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1524         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1525         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1526
1527         // calculate the edge normal and reject if impact is outside triangle
1528         // (an edge normal faces away from the triangle, to get the desired normal
1529         //  a crossproduct with the faceplanenormal is used, and because of the way
1530         // the insidedness comparison is written it does not need to be normalized)
1531
1532         VectorSubtract(point2, point0, edge);
1533         CrossProduct(edge, faceplanenormal, edgenormal);
1534         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1535                 return;
1536
1537         VectorSubtract(point0, point1, edge);
1538         CrossProduct(edge, faceplanenormal, edgenormal);
1539         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1540                 return;
1541
1542         VectorSubtract(point1, point2, edge);
1543         CrossProduct(edge, faceplanenormal, edgenormal);
1544         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1545                 return;
1546
1547         // store the new trace fraction
1548         trace->realfraction = bound(0, f, 1);
1549
1550         // store the new trace plane (because collisions only happen from
1551         // the front this is always simply the triangle normal, never flipped)
1552         VectorNormalize(faceplanenormal);
1553         VectorCopy(faceplanenormal, trace->plane.normal);
1554         trace->plane.dist = DotProduct(point0, faceplanenormal);
1555
1556         // calculate the normalized start and end distances
1557         d1 = DotProduct(trace->plane.normal, linestart) - trace->plane.dist;
1558         d2 = DotProduct(trace->plane.normal, lineend) - trace->plane.dist;
1559
1560         // calculate a nudged fraction to keep it out of the surface
1561         // (the main fraction remains perfect)
1562         fnudged = (d1 - collision_impactnudge.value) / (d1 - d2);
1563         trace->fraction = bound(0, fnudged, 1);
1564
1565         // store the new trace endpos
1566         // not needed, it's calculated later when the trace is finished
1567         //trace->endpos[0] = linestart[0] + fnudged * (lineend[0] - linestart[0]);
1568         //trace->endpos[1] = linestart[1] + fnudged * (lineend[1] - linestart[1]);
1569         //trace->endpos[2] = linestart[2] + fnudged * (lineend[2] - linestart[2]);
1570 #endif
1571 }
1572
1573 typedef struct colbspnode_s
1574 {
1575         mplane_t plane;
1576         struct colbspnode_s *children[2];
1577         // the node is reallocated or split if max is reached
1578         int numcolbrushf;
1579         int maxcolbrushf;
1580         colbrushf_t **colbrushflist;
1581         //int numcolbrushd;
1582         //int maxcolbrushd;
1583         //colbrushd_t **colbrushdlist;
1584 }
1585 colbspnode_t;
1586
1587 typedef struct colbsp_s
1588 {
1589         mempool_t *mempool;
1590         colbspnode_t *nodes;
1591 }
1592 colbsp_t;
1593
1594 colbsp_t *Collision_CreateCollisionBSP(mempool_t *mempool)
1595 {
1596         colbsp_t *bsp;
1597         bsp = Mem_Alloc(mempool, sizeof(colbsp_t));
1598         bsp->mempool = mempool;
1599         bsp->nodes = Mem_Alloc(bsp->mempool, sizeof(colbspnode_t));
1600         return bsp;
1601 }
1602
1603 void Collision_FreeCollisionBSPNode(colbspnode_t *node)
1604 {
1605         if (node->children[0])
1606                 Collision_FreeCollisionBSPNode(node->children[0]);
1607         if (node->children[1])
1608                 Collision_FreeCollisionBSPNode(node->children[1]);
1609         while (--node->numcolbrushf)
1610                 Mem_Free(node->colbrushflist[node->numcolbrushf]);
1611         //while (--node->numcolbrushd)
1612         //      Mem_Free(node->colbrushdlist[node->numcolbrushd]);
1613         Mem_Free(node);
1614 }
1615
1616 void Collision_FreeCollisionBSP(colbsp_t *bsp)
1617 {
1618         Collision_FreeCollisionBSPNode(bsp->nodes);
1619         Mem_Free(bsp);
1620 }
1621
1622 void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const colbrushf_t *end, vec3_t mins, vec3_t maxs, float startfrac, float endfrac)
1623 {
1624         int i;
1625         colpointf_t *ps, *pe;
1626         float tempstart[3], tempend[3];
1627         VectorLerp(start->points[0].v, startfrac, end->points[0].v, mins);
1628         VectorCopy(mins, maxs);
1629         for (i = 0, ps = start->points, pe = end->points;i < start->numpoints;i++, ps++, pe++)
1630         {
1631                 VectorLerp(ps->v, startfrac, pe->v, tempstart);
1632                 VectorLerp(ps->v, endfrac, pe->v, tempend);
1633                 mins[0] = min(mins[0], min(tempstart[0], tempend[0]));
1634                 mins[1] = min(mins[1], min(tempstart[1], tempend[1]));
1635                 mins[2] = min(mins[2], min(tempstart[2], tempend[2]));
1636                 maxs[0] = min(maxs[0], min(tempstart[0], tempend[0]));
1637                 maxs[1] = min(maxs[1], min(tempstart[1], tempend[1]));
1638                 maxs[2] = min(maxs[2], min(tempstart[2], tempend[2]));
1639         }
1640         mins[0] -= 1;
1641         mins[1] -= 1;
1642         mins[2] -= 1;
1643         maxs[0] += 1;
1644         maxs[1] += 1;
1645         maxs[2] += 1;
1646 }
1647