collision.c

   1
   2 #include "quakedef.h"
   3 #include "polygon.h"
   4
   5 #define COLLISION_SNAPSCALE (32.0f)
   6 #define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
   7 #define COLLISION_SNAP2 (2.0f / COLLISION_SNAPSCALE)
   8 #define COLLISION_PLANE_DIST_EPSILON (2.0f / COLLISION_SNAPSCALE)
   9
  10 cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125", "how much to back off from the impact"};
  11 cvar_t collision_startnudge = {0, "collision_startnudge", "0", "how much to bias collision trace start"};
  12 cvar_t collision_endnudge = {0, "collision_endnudge", "0", "how much to bias collision trace end"};
  13 cvar_t collision_enternudge = {0, "collision_enternudge", "0", "how much to bias collision entry fraction"};
  14 cvar_t collision_leavenudge = {0, "collision_leavenudge", "0", "how much to bias collision exit fraction"};
  15 cvar_t collision_prefernudgedfraction = {0, "collision_prefernudgedfraction", "1", "whether to sort collision events by nudged fraction (1) or real fraction (0)"};
  16
  17 void Collision_Init (void)
  18 {
  19         Cvar_RegisterVariable(&collision_impactnudge);
  20         Cvar_RegisterVariable(&collision_startnudge);
  21         Cvar_RegisterVariable(&collision_endnudge);
  22         Cvar_RegisterVariable(&collision_enternudge);
  23         Cvar_RegisterVariable(&collision_leavenudge);
  24         Cvar_RegisterVariable(&collision_prefernudgedfraction);
  25 }
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40 void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
  41 {
  42         int i;
  43         Con_Printf("3 %s\n%i\n", name, brush->numpoints);
  44         for (i = 0;i < brush->numpoints;i++)
  45                 Con_Printf("%f %f %f\n", brush->points[i].v[0], brush->points[i].v[1], brush->points[i].v[2]);
  46         // FIXME: optimize!
  47         Con_Printf("4\n%i\n", brush->numplanes);
  48         for (i = 0;i < brush->numplanes;i++)
  49                 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);
  50 }
  51
  52 void Collision_ValidateBrush(colbrushf_t *brush)
  53 {
  54         int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
  55         float d;
  56         printbrush = false;
  57         if (!brush->numpoints)
  58         {
  59                 Con_Print("Collision_ValidateBrush: brush with no points!\n");
  60                 printbrush = true;
  61         }
  62 #if 0
  63         // it's ok for a brush to have one point and no planes...
  64         if (brush->numplanes == 0 && brush->numpoints != 1)
  65         {
  66                 Con_Print("Collision_ValidateBrush: brush with no planes and more than one point!\n");
  67                 printbrush = true;
  68         }
  69 #endif
  70         if (brush->numplanes)
  71         {
  72                 pointsoffplanes = 0;
  73                 pointswithinsufficientplanes = 0;
  74                 for (k = 0;k < brush->numplanes;k++)
  75                         if (DotProduct(brush->planes[k].normal, brush->planes[k].normal) < 0.0001f)
  76                                 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);
  77                 for (j = 0;j < brush->numpoints;j++)
  78                 {
  79                         pointonplanes = 0;
  80                         for (k = 0;k < brush->numplanes;k++)
  81                         {
  82                                 d = DotProduct(brush->points[j].v, brush->planes[k].normal) - brush->planes[k].dist;
  83                                 if (d > COLLISION_PLANE_DIST_EPSILON)
  84                                 {
  85                                         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);
  86                                         printbrush = true;
  87                                 }
  88                                 if (fabs(d) > COLLISION_PLANE_DIST_EPSILON)
  89                                         pointsoffplanes++;
  90                                 else
  91                                         pointonplanes++;
  92                         }
  93                         if (pointonplanes < 3)
  94                                 pointswithinsufficientplanes++;
  95                 }
  96                 if (pointswithinsufficientplanes)
  97                 {
  98                         Con_Print("Collision_ValidateBrush: some points have insufficient planes, every point must be on at least 3 planes to form a corner.\n");
  99                         printbrush = true;
 100                 }
 101                 if (pointsoffplanes == 0) // all points are on all planes
 102                 {
 103                         Con_Print("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
 104                         printbrush = true;
 105                 }
 106         }
 107         if (printbrush)
 108                 Collision_PrintBrushAsQHull(brush, "unnamed");
 109 }
 110
 111 float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 112 {
 113         float dist, bestdist;
 114         if (!numpoints)
 115                 return 0;
 116         bestdist = DotProduct(points->v, normal);
 117         points++;
 118         while(--numpoints)
 119         {
 120                 dist = DotProduct(points->v, normal);
 121                 bestdist = min(bestdist, dist);
 122                 points++;
 123         }
 124         return bestdist;
 125 }
 126
 127 float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 128 {
 129         float dist, bestdist;
 130         if (!numpoints)
 131                 return 0;
 132         bestdist = DotProduct(points->v, normal);
 133         points++;
 134         while(--numpoints)
 135         {
 136                 dist = DotProduct(points->v, normal);
 137                 bestdist = max(bestdist, dist);
 138                 points++;
 139         }
 140         return bestdist;
 141 }
 142
 143
 144 colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const colplanef_t *originalplanes, int supercontents)
 145 {
 146         // TODO: planesbuf could be replaced by a remapping table
 147         int j, k, m, w, xyzflags;
 148         int numpointsbuf = 0, maxpointsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
 149         double maxdist;
 150         colbrushf_t *brush;
 151         colpointf_t pointsbuf[256];
 152         colplanef_t planesbuf[256];
 153         int elementsbuf[1024];
 154         int polypointbuf[256];
 155         int pmaxpoints = 64;
 156         int pnumpoints;
 157         double p[2][3*64];
 158 #if 0
 159         // enable these if debugging to avoid seeing garbage in unused data
 160         memset(pointsbuf, 0, sizeof(pointsbuf));
 161         memset(planesbuf, 0, sizeof(planesbuf));
 162         memset(elementsbuf, 0, sizeof(elementsbuf));
 163         memset(polypointbuf, 0, sizeof(polypointbuf));
 164         memset(p, 0, sizeof(p));
 165 #endif
 166         // figure out how large a bounding box we need to properly compute this brush
 167         maxdist = 0;
 168         for (j = 0;j < numoriginalplanes;j++)
 169                 maxdist = max(maxdist, fabs(originalplanes[j].dist));
 170         // now make it large enough to enclose the entire brush, and round it off to a reasonable multiple of 1024
 171         maxdist = floor(maxdist * (4.0 / 1024.0) + 2) * 1024.0;
 172         // construct a collision brush (points, planes, and renderable mesh) from
 173         // a set of planes, this also optimizes out any unnecessary planes (ones
 174         // whose polygon is clipped away by the other planes)
 175         for (j = 0;j < numoriginalplanes;j++)
 176         {
 177                 // add the plane uniquely (no duplicates)
 178                 for (k = 0;k < numplanesbuf;k++)
 179                         if (VectorCompare(planesbuf[k].normal, originalplanes[j].normal) && planesbuf[k].dist == originalplanes[j].dist)
 180                                 break;
 181                 // if the plane is a duplicate, skip it
 182                 if (k < numplanesbuf)
 183                         continue;
 184                 // check if there are too many and skip the brush
 185                 if (numplanesbuf >= maxplanesbuf)
 186                 {
 187                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
 188                         return NULL;
 189                 }
 190
 191                 // add the new plane
 192                 VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
 193                 planesbuf[numplanesbuf].dist = originalplanes[j].dist;
 194                 planesbuf[numplanesbuf].q3surfaceflags = originalplanes[j].q3surfaceflags;
 195                 planesbuf[numplanesbuf].texture = originalplanes[j].texture;
 196                 numplanesbuf++;
 197
 198                 // create a large polygon from the plane
 199                 w = 0;
 200                 PolygonD_QuadForPlane(p[w], originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist, maxdist);
 201                 pnumpoints = 4;
 202                 // clip it by all other planes
 203                 for (k = 0;k < numoriginalplanes && pnumpoints >= 3 && pnumpoints <= pmaxpoints;k++)
 204                 {
 205                         // skip the plane this polygon
 206                         // (nothing happens if it is processed, this is just an optimization)
 207                         if (k != j)
 208                         {
 209                                 // we want to keep the inside of the brush plane so we flip
 210                                 // the cutting plane
 211                                 PolygonD_Divide(pnumpoints, p[w], -originalplanes[k].normal[0], -originalplanes[k].normal[1], -originalplanes[k].normal[2], -originalplanes[k].dist, COLLISION_PLANE_DIST_EPSILON, pmaxpoints, p[!w], &pnumpoints, 0, NULL, NULL, NULL);
 212                                 w = !w;
 213                         }
 214                 }
 215
 216                 // if nothing is left, skip it
 217                 if (pnumpoints < 3)
 218                 {
 219                         //Con_DPrintf("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);
 220                         continue;
 221                 }
 222
 223                 for (k = 0;k < pnumpoints;k++)
 224                 {
 225                         int l, m;
 226                         m = 0;
 227                         for (l = 0;l < numoriginalplanes;l++)
 228                                 if (fabs(DotProduct(&p[w][k*3], originalplanes[l].normal) - originalplanes[l].dist) < COLLISION_PLANE_DIST_EPSILON)
 229                                         m++;
 230                         if (m < 3)
 231                                 break;
 232                 }
 233                 if (k < pnumpoints)
 234                 {
 235                         Con_DPrintf("Collision_NewBrushFromPlanes: warning: polygon point does not lie on at least 3 planes\n");
 236                         //return NULL;
 237                 }
 238
 239                 // check if there are too many polygon vertices for buffer
 240                 if (pnumpoints > pmaxpoints)
 241                 {
 242                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 243                         return NULL;
 244                 }
 245
 246                 // check if there are too many triangle elements for buffer
 247                 if (numelementsbuf + (pnumpoints - 2) * 3 > maxelementsbuf)
 248                 {
 249                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
 250                         return NULL;
 251                 }
 252
 253                 for (k = 0;k < pnumpoints;k++)
 254                 {
 255                         float v[3];
 256                         // downgrade to float precision before comparing
 257                         VectorCopy(&p[w][k*3], v);
 258
 259                         // check if there is already a matching point (no duplicates)
 260                         for (m = 0;m < numpointsbuf;m++)
 261                                 if (VectorDistance2(v, pointsbuf[m].v) < COLLISION_SNAP2)
 262                                         break;
 263
 264                         // if there is no match, add a new one
 265                         if (m == numpointsbuf)
 266                         {
 267                                 // check if there are too many and skip the brush
 268                                 if (numpointsbuf >= maxpointsbuf)
 269                                 {
 270                                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 271                                         return NULL;
 272                                 }
 273                                 // add the new one
 274                                 VectorCopy(&p[w][k*3], pointsbuf[numpointsbuf].v);
 275                                 numpointsbuf++;
 276                         }
 277
 278                         // store the index into a buffer
 279                         polypointbuf[k] = m;
 280                 }
 281
 282                 // add the triangles for the polygon
 283                 // (this particular code makes a triangle fan)
 284                 for (k = 0;k < pnumpoints - 2;k++)
 285                 {
 286                         elementsbuf[numelementsbuf++] = polypointbuf[0];
 287                         elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
 288                         elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
 289                 }
 290         }
 291
 292         // if nothing is left, there's nothing to allocate
 293         if (numplanesbuf < 4)
 294         {
 295                 Con_DPrintf("Collision_NewBrushFromPlanes: failed to build collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
 296                 return NULL;
 297         }
 298
 299         // if no triangles or points could be constructed, then this routine failed but the brush is not discarded
 300         if (numelementsbuf < 12 || numpointsbuf < 4)
 301                 Con_DPrintf("Collision_NewBrushFromPlanes: unable to rebuild triangles/points for collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
 302
 303         // validate plane distances
 304         for (j = 0;j < numplanesbuf;j++)
 305         {
 306                 float d = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpointsbuf);
 307                 if (fabs(planesbuf[j].dist - d) > COLLISION_PLANE_DIST_EPSILON)
 308                         Con_DPrintf("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);
 309         }
 310
 311         // allocate the brush and copy to it
 312         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpointsbuf + sizeof(colplanef_t) * numplanesbuf + sizeof(int) * numelementsbuf);
 313         brush->supercontents = supercontents;
 314         brush->numplanes = numplanesbuf;
 315         brush->numpoints = numpointsbuf;
 316         brush->numtriangles = numelementsbuf / 3;
 317         brush->planes = (colplanef_t *)(brush + 1);
 318         brush->points = (colpointf_t *)(brush->planes + brush->numplanes);
 319         brush->elements = (int *)(brush->points + brush->numpoints);
 320         for (j = 0;j < brush->numpoints;j++)
 321         {
 322                 brush->points[j].v[0] = pointsbuf[j].v[0];
 323                 brush->points[j].v[1] = pointsbuf[j].v[1];
 324                 brush->points[j].v[2] = pointsbuf[j].v[2];
 325         }
 326         for (j = 0;j < brush->numplanes;j++)
 327         {
 328                 brush->planes[j].normal[0] = planesbuf[j].normal[0];
 329                 brush->planes[j].normal[1] = planesbuf[j].normal[1];
 330                 brush->planes[j].normal[2] = planesbuf[j].normal[2];
 331                 brush->planes[j].dist = planesbuf[j].dist;
 332                 brush->planes[j].q3surfaceflags = planesbuf[j].q3surfaceflags;
 333                 brush->planes[j].texture = planesbuf[j].texture;
 334         }
 335         for (j = 0;j < brush->numtriangles * 3;j++)
 336                 brush->elements[j] = elementsbuf[j];
 337
 338         xyzflags = 0;
 339         VectorClear(brush->mins);
 340         VectorClear(brush->maxs);
 341         for (j = 0;j < min(6, numoriginalplanes);j++)
 342         {
 343                      if (originalplanes[j].normal[0] ==  1) {xyzflags |=  1;brush->maxs[0] =  originalplanes[j].dist;}
 344                 else if (originalplanes[j].normal[0] == -1) {xyzflags |=  2;brush->mins[0] = -originalplanes[j].dist;}
 345                 else if (originalplanes[j].normal[1] ==  1) {xyzflags |=  4;brush->maxs[1] =  originalplanes[j].dist;}
 346                 else if (originalplanes[j].normal[1] == -1) {xyzflags |=  8;brush->mins[1] = -originalplanes[j].dist;}
 347                 else if (originalplanes[j].normal[2] ==  1) {xyzflags |= 16;brush->maxs[2] =  originalplanes[j].dist;}
 348                 else if (originalplanes[j].normal[2] == -1) {xyzflags |= 32;brush->mins[2] = -originalplanes[j].dist;}
 349         }
 350         // if not all xyzflags were set, then this is not a brush from q3map/q3map2, and needs reconstruction of the bounding box
 351         // (this case works for any brush with valid points, but sometimes brushes are not reconstructed properly and hence the points are not valid, so this is reserved as a fallback case)
 352         if (xyzflags != 63)
 353         {
 354                 VectorCopy(brush->points[0].v, brush->mins);
 355                 VectorCopy(brush->points[0].v, brush->maxs);
 356                 for (j = 1;j < brush->numpoints;j++)
 357                 {
 358                         brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
 359                         brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
 360                         brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
 361                         brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
 362                         brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
 363                         brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
 364                 }
 365         }
 366         brush->mins[0] -= 1;
 367         brush->mins[1] -= 1;
 368         brush->mins[2] -= 1;
 369         brush->maxs[0] += 1;
 370         brush->maxs[1] += 1;
 371         brush->maxs[2] += 1;
 372         Collision_ValidateBrush(brush);
 373         return brush;
 374 }
 375
 376
 377
 378 void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
 379 {
 380         int i;
 381         float edge0[3], edge1[3], edge2[3], normal[3], dist, bestdist;
 382         colpointf_t *p, *p2;
 383
 384         // FIXME: these probably don't actually need to be normalized if the collision code does not care
 385         if (brush->numpoints == 3)
 386         {
 387                 // optimized triangle case
 388                 TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
 389                 if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
 390                 {
 391                         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 392                         brush->numplanes = 0;
 393                         return;
 394                 }
 395                 else
 396                 {
 397                         brush->numplanes = 5;
 398                         VectorNormalize(brush->planes[0].normal);
 399                         brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
 400                         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 401                         brush->planes[1].dist = -brush->planes[0].dist;
 402                         VectorSubtract(brush->points[2].v, brush->points[0].v, edge0);
 403                         VectorSubtract(brush->points[0].v, brush->points[1].v, edge1);
 404                         VectorSubtract(brush->points[1].v, brush->points[2].v, edge2);
 405 #if 1
 406                         {
 407                                 float projectionnormal[3], projectionedge0[3], projectionedge1[3], projectionedge2[3];
 408                                 int i, best;
 409                                 float dist, bestdist;
 410                                 bestdist = fabs(brush->planes[0].normal[0]);
 411                                 best = 0;
 412                                 for (i = 1;i < 3;i++)
 413                                 {
 414                                         dist = fabs(brush->planes[0].normal[i]);
 415                                         if (bestdist < dist)
 416                                         {
 417                                                 bestdist = dist;
 418                                                 best = i;
 419                                         }
 420                                 }
 421                                 VectorClear(projectionnormal);
 422                                 if (brush->planes[0].normal[best] < 0)
 423                                         projectionnormal[best] = -1;
 424                                 else
 425                                         projectionnormal[best] = 1;
 426                                 VectorCopy(edge0, projectionedge0);
 427                                 VectorCopy(edge1, projectionedge1);
 428                                 VectorCopy(edge2, projectionedge2);
 429                                 projectionedge0[best] = 0;
 430                                 projectionedge1[best] = 0;
 431                                 projectionedge2[best] = 0;
 432                                 CrossProduct(projectionedge0, projectionnormal, brush->planes[2].normal);
 433                                 CrossProduct(projectionedge1, projectionnormal, brush->planes[3].normal);
 434                                 CrossProduct(projectionedge2, projectionnormal, brush->planes[4].normal);
 435                         }
 436 #else
 437                         CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 438                         CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 439                         CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 440 #endif
 441                         VectorNormalize(brush->planes[2].normal);
 442                         VectorNormalize(brush->planes[3].normal);
 443                         VectorNormalize(brush->planes[4].normal);
 444                         brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
 445                         brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
 446                         brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
 447
 448                         if (developer.integer >= 100)
 449                         {
 450                                 // validation code
 451 #if 0
 452                                 float temp[3];
 453
 454                                 VectorSubtract(brush->points[0].v, brush->points[1].v, edge0);
 455                                 VectorSubtract(brush->points[2].v, brush->points[1].v, edge1);
 456                                 CrossProduct(edge0, edge1, normal);
 457                                 VectorNormalize(normal);
 458                                 VectorSubtract(normal, brush->planes[0].normal, temp);
 459                                 if (VectorLength(temp) > 0.01f)
 460                                         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]);
 461                                 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)
 462                                         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);
 463 #if 0
 464                                 if (fabs(DotProduct(brush->planes[2].normal, brush->planes[0].normal)) > 0.01f)
 465                                         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);
 466                                 if (fabs(DotProduct(brush->planes[3].normal, brush->planes[0].normal)) > 0.01f)
 467                                         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);
 468                                 if (fabs(DotProduct(brush->planes[4].normal, brush->planes[0].normal)) > 0.01f)
 469                                         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);
 470                                 if (fabs(DotProduct(brush->planes[2].normal, edge0)) > 0.01f)
 471                                         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]);
 472                                 if (fabs(DotProduct(brush->planes[3].normal, edge1)) > 0.01f)
 473                                         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]);
 474                                 if (fabs(DotProduct(brush->planes[4].normal, edge2)) > 0.01f)
 475                                         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]);
 476 #endif
 477 #endif
 478                                 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)
 479                                         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);
 480                                 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)
 481                                         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);
 482                                 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)
 483                                         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);
 484                                 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)
 485                                         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);
 486                                 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)
 487                                         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);
 488                         }
 489                 }
 490         }
 491         else
 492         {
 493                 // choose best surface normal for polygon's plane
 494                 bestdist = 0;
 495                 for (i = 0, p = brush->points + 1;i < brush->numpoints - 2;i++, p++)
 496                 {
 497                         VectorSubtract(p[-1].v, p[0].v, edge0);
 498                         VectorSubtract(p[1].v, p[0].v, edge1);
 499                         CrossProduct(edge0, edge1, normal);
 500                         //TriangleNormal(p[-1].v, p[0].v, p[1].v, normal);
 501                         dist = DotProduct(normal, normal);
 502                         if (i == 0 || bestdist < dist)
 503                         {
 504                                 bestdist = dist;
 505                                 VectorCopy(normal, brush->planes->normal);
 506                         }
 507                 }
 508                 if (bestdist < 0.0001f)
 509                 {
 510                         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 511                         brush->numplanes = 0;
 512                         return;
 513                 }
 514                 else
 515                 {
 516                         brush->numplanes = brush->numpoints + 2;
 517                         VectorNormalize(brush->planes->normal);
 518                         brush->planes->dist = DotProduct(brush->points->v, brush->planes->normal);
 519
 520                         // negate plane to create other side
 521                         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 522                         brush->planes[1].dist = -brush->planes[0].dist;
 523                         for (i = 0, p = brush->points + (brush->numpoints - 1), p2 = brush->points;i < brush->numpoints;i++, p = p2, p2++)
 524                         {
 525                                 VectorSubtract(p->v, p2->v, edge0);
 526                                 CrossProduct(edge0, brush->planes->normal, brush->planes[i + 2].normal);
 527                                 VectorNormalize(brush->planes[i + 2].normal);
 528                                 brush->planes[i + 2].dist = DotProduct(p->v, brush->planes[i + 2].normal);
 529                         }
 530                 }
 531         }
 532
 533         if (developer.integer >= 100)
 534         {
 535                 // validity check - will be disabled later
 536                 Collision_ValidateBrush(brush);
 537                 for (i = 0;i < brush->numplanes;i++)
 538                 {
 539                         int j;
 540                         for (j = 0, p = brush->points;j < brush->numpoints;j++, p++)
 541                                 if (DotProduct(p->v, brush->planes[i].normal) > brush->planes[i].dist + COLLISION_PLANE_DIST_EPSILON)
 542                                         Con_Printf("Error in brush plane generation, plane %i\n", i);
 543                 }
 544         }
 545 }
 546
 547 colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents)
 548 {
 549         colbrushf_t *brush;
 550         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2));
 551         brush->supercontents = supercontents;
 552         brush->numpoints = numpoints;
 553         brush->numplanes = numpoints + 2;
 554         brush->planes = (colplanef_t *)(brush + 1);
 555         brush->points = (colpointf_t *)points;
 556         Sys_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...");
 557         return brush;
 558 }
 559
 560 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 561 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)
 562 {
 563         int nplane, nplane2, hitq3surfaceflags = 0;
 564         float enterfrac = -1, leavefrac = 1, d1, d2, f, imove, newimpactnormal[3], enterfrac2 = -1;
 565         const colplanef_t *startplane, *endplane;
 566         texture_t *hittexture = NULL;
 567
 568         VectorClear(newimpactnormal);
 569
 570         for (nplane = 0;nplane < thatbrush_start->numplanes + thisbrush_start->numplanes;nplane++)
 571         {
 572                 nplane2 = nplane;
 573                 if (nplane2 >= thatbrush_start->numplanes)
 574                 {
 575                         nplane2 -= thatbrush_start->numplanes;
 576                         startplane = thisbrush_start->planes + nplane2;
 577                         endplane = thisbrush_end->planes + nplane2;
 578                         if (developer.integer >= 100)
 579                         {
 580                                 // any brush with degenerate planes is not worth handling
 581                                 if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 582                                 {
 583                                         Con_Print("Collision_TraceBrushBrushFloat: degenerate thisbrush plane!\n");
 584                                         return;
 585                                 }
 586                                 f = furthestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints);
 587                                 if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
 588                                         Con_Printf("startplane->dist %f != calculated %f (thisbrush_start)\n", startplane->dist, f);
 589                         }
 590                         d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints) - collision_startnudge.value;
 591                         d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints) - collision_endnudge.value;
 592                 }
 593                 else
 594                 {
 595                         startplane = thatbrush_start->planes + nplane2;
 596                         endplane = thatbrush_end->planes + nplane2;
 597                         if (developer.integer >= 100)
 598                         {
 599                                 // any brush with degenerate planes is not worth handling
 600                                 if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 601                                 {
 602                                         Con_Print("Collision_TraceBrushBrushFloat: degenerate thatbrush plane!\n");
 603                                         return;
 604                                 }
 605                                 f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
 606                                 if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
 607                                         Con_Printf("startplane->dist %f != calculated %f (thatbrush_start)\n", startplane->dist, f);
 608                         }
 609                         d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - startplane->dist - collision_startnudge.value;
 610                         d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - endplane->dist - collision_endnudge.value;
 611                 }
 612                 //Con_Printf("%c%i: d1 = %f, d2 = %f, d1 / (d1 - d2) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, d1, d2, d1 / (d1 - d2));
 613
 614                 if (d1 > d2)
 615                 {
 616                         // moving into brush
 617                         if (d2 >= collision_enternudge.value)
 618                                 return;
 619                         if (d1 > 0)
 620                         {
 621                                 // enter
 622                                 imove = 1 / (d1 - d2);
 623                                 f = (d1 - collision_enternudge.value) * imove;
 624                                 if (f < 0)
 625                                         f = 0;
 626                                 // check if this will reduce the collision time range
 627                                 if (enterfrac < f)
 628                                 {
 629                                         // reduced collision time range
 630                                         enterfrac = f;
 631                                         // if the collision time range is now empty, no collision
 632                                         if (enterfrac > leavefrac)
 633                                                 return;
 634                                         // if the collision would be further away than the trace's
 635                                         // existing collision data, we don't care about this
 636                                         // collision
 637                                         if (enterfrac > trace->realfraction)
 638                                                 return;
 639                                         // calculate the nudged fraction and impact normal we'll
 640                                         // need if we accept this collision later
 641                                         enterfrac2 = (d1 - collision_impactnudge.value) * imove;
 642                                         VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
 643                                         hitq3surfaceflags = startplane->q3surfaceflags;
 644                                         hittexture = startplane->texture;
 645                                 }
 646                         }
 647                 }
 648                 else
 649                 {
 650                         // moving out of brush
 651                         if (d1 > 0)
 652                                 return;
 653                         if (d2 > 0)
 654                         {
 655                                 // leave
 656                                 f = (d1 + collision_leavenudge.value) / (d1 - d2);
 657                                 if (f > 1)
 658                                         f = 1;
 659                                 // check if this will reduce the collision time range
 660                                 if (leavefrac > f)
 661                                 {
 662                                         // reduced collision time range
 663                                         leavefrac = f;
 664                                         // if the collision time range is now empty, no collision
 665                                         if (enterfrac > leavefrac)
 666                                                 return;
 667                                 }
 668                         }
 669                 }
 670         }
 671
 672         // at this point we know the trace overlaps the brush because it was not
 673         // rejected at any point in the loop above
 674
 675         // see if the trace started outside the brush or not
 676         if (enterfrac > -1)
 677         {
 678                 // started outside, and overlaps, therefore there is a collision here
 679                 // store out the impact information
 680                 if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
 681                 {
 682                         trace->hitsupercontents = thatbrush_start->supercontents;
 683                         trace->hitq3surfaceflags = hitq3surfaceflags;
 684                         trace->hittexture = hittexture;
 685                         trace->realfraction = bound(0, enterfrac, 1);
 686                         trace->fraction = bound(0, enterfrac2, 1);
 687                         if (collision_prefernudgedfraction.integer)
 688                                 trace->realfraction = trace->fraction;
 689                         VectorCopy(newimpactnormal, trace->plane.normal);
 690                 }
 691         }
 692         else
 693         {
 694                 // started inside, update startsolid and friends
 695                 trace->startsupercontents |= thatbrush_start->supercontents;
 696                 if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
 697                 {
 698                         trace->startsolid = true;
 699                         if (leavefrac < 1)
 700                                 trace->allsolid = true;
 701                         VectorCopy(newimpactnormal, trace->plane.normal);
 702                 }
 703         }
 704 }
 705
 706 // NOTE: start and end brush pair must have same numplanes/numpoints
 707 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 708 {
 709         int nplane, hitq3surfaceflags = 0;
 710         float enterfrac = -1, leavefrac = 1, d1, d2, f, imove, newimpactnormal[3], enterfrac2 = -1;
 711         const colplanef_t *startplane, *endplane;
 712         texture_t *hittexture = NULL;
 713
 714         VectorClear(newimpactnormal);
 715
 716         for (nplane = 0;nplane < thatbrush_start->numplanes;nplane++)
 717         {
 718                 startplane = thatbrush_start->planes + nplane;
 719                 endplane = thatbrush_end->planes + nplane;
 720                 d1 = DotProduct(startplane->normal, linestart) - startplane->dist - collision_startnudge.value;
 721                 d2 = DotProduct(endplane->normal, lineend) - endplane->dist - collision_endnudge.value;
 722                 if (developer.integer >= 100)
 723                 {
 724                         // any brush with degenerate planes is not worth handling
 725                         if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
 726                         {
 727                                 Con_Print("Collision_TraceLineBrushFloat: degenerate plane!\n");
 728                                 return;
 729                         }
 730                         if (thatbrush_start->numpoints)
 731                         {
 732                                 f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
 733                                 if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
 734                                         Con_Printf("startplane->dist %f != calculated %f\n", startplane->dist, f);
 735                         }
 736                 }
 737
 738                 if (d1 > d2)
 739                 {
 740                         // moving into brush
 741                         if (d2 >= collision_enternudge.value)
 742                                 return;
 743                         if (d1 > 0)
 744                         {
 745                                 // enter
 746                                 imove = 1 / (d1 - d2);
 747                                 f = (d1 - collision_enternudge.value) * imove;
 748                                 if (f < 0)
 749                                         f = 0;
 750                                 // check if this will reduce the collision time range
 751                                 if (enterfrac < f)
 752                                 {
 753                                         // reduced collision time range
 754                                         enterfrac = f;
 755                                         // if the collision time range is now empty, no collision
 756                                         if (enterfrac > leavefrac)
 757                                                 return;
 758                                         // if the collision would be further away than the trace's
 759                                         // existing collision data, we don't care about this
 760                                         // collision
 761                                         if (enterfrac > trace->realfraction)
 762                                                 return;
 763                                         // calculate the nudged fraction and impact normal we'll
 764                                         // need if we accept this collision later
 765                                         enterfrac2 = (d1 - collision_impactnudge.value) * imove;
 766                                         VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
 767                                         hitq3surfaceflags = startplane->q3surfaceflags;
 768                                         hittexture = startplane->texture;
 769                                 }
 770                         }
 771                 }
 772                 else
 773                 {
 774                         // moving out of brush
 775                         if (d1 > 0)
 776                                 return;
 777                         if (d2 > 0)
 778                         {
 779                                 // leave
 780                                 f = (d1 + collision_leavenudge.value) / (d1 - d2);
 781                                 // check if this will reduce the collision time range
 782                                 if (leavefrac > f)
 783                                 {
 784                                         // reduced collision time range
 785                                         leavefrac = f;
 786                                         // if the collision time range is now empty, no collision
 787                                         if (enterfrac > leavefrac)
 788                                                 return;
 789                                 }
 790                         }
 791                 }
 792         }
 793
 794         // at this point we know the trace overlaps the brush because it was not
 795         // rejected at any point in the loop above
 796
 797         // see if the trace started outside the brush or not
 798         if (enterfrac > -1)
 799         {
 800                 // started outside, and overlaps, therefore there is a collision here
 801                 // store out the impact information
 802                 if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
 803                 {
 804                         trace->hitsupercontents = thatbrush_start->supercontents;
 805                         trace->hitq3surfaceflags = hitq3surfaceflags;
 806                         trace->hittexture = hittexture;
 807                         trace->realfraction = bound(0, enterfrac, 1);
 808                         trace->fraction = bound(0, enterfrac2, 1);
 809                         if (collision_prefernudgedfraction.integer)
 810                                 trace->realfraction = trace->fraction;
 811                         VectorCopy(newimpactnormal, trace->plane.normal);
 812                 }
 813         }
 814         else
 815         {
 816                 // started inside, update startsolid and friends
 817                 trace->startsupercontents |= thatbrush_start->supercontents;
 818                 if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
 819                 {
 820                         trace->startsolid = true;
 821                         if (leavefrac < 1)
 822                                 trace->allsolid = true;
 823                         VectorCopy(newimpactnormal, trace->plane.normal);
 824                 }
 825         }
 826 }
 827
 828 qboolean Collision_PointInsideBrushFloat(const vec3_t point, const colbrushf_t *brush)
 829 {
 830         int nplane;
 831         const colplanef_t *plane;
 832
 833         if (!BoxesOverlap(point, point, brush->mins, brush->maxs))
 834                 return false;
 835         for (nplane = 0, plane = brush->planes;nplane < brush->numplanes;nplane++, plane++)
 836                 if (DotProduct(plane->normal, point) > plane->dist)
 837                         return false;
 838         return true;
 839 }
 840
 841 void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
 842 {
 843         if (!Collision_PointInsideBrushFloat(point, thatbrush))
 844                 return;
 845
 846         trace->startsupercontents |= thatbrush->supercontents;
 847         if (trace->hitsupercontentsmask & thatbrush->supercontents)
 848         {
 849                 trace->startsolid = true;
 850                 trace->allsolid = true;
 851         }
 852 }
 853
 854 static colpointf_t polyf_points[256];
 855 static colplanef_t polyf_planes[256 + 2];
 856 static colbrushf_t polyf_brush;
 857
 858 void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
 859 {
 860         int i;
 861         for (i = 0;i < numpoints;i++)
 862         {
 863                 out[i].v[0] = floor(in[i].v[0] * fractionprecision + 0.5f) * invfractionprecision;
 864                 out[i].v[1] = floor(in[i].v[1] * fractionprecision + 0.5f) * invfractionprecision;
 865                 out[i].v[2] = floor(in[i].v[2] * fractionprecision + 0.5f) * invfractionprecision;
 866         }
 867 }
 868
 869 void Collision_TraceBrushPolygonFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numpoints, const float *points, int supercontents)
 870 {
 871         if (numpoints > 256)
 872         {
 873                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
 874                 return;
 875         }
 876         polyf_brush.numpoints = numpoints;
 877         polyf_brush.numplanes = numpoints + 2;
 878         //polyf_brush.points = (colpointf_t *)points;
 879         polyf_brush.planes = polyf_planes;
 880         polyf_brush.supercontents = supercontents;
 881         polyf_brush.points = polyf_points;
 882         Collision_SnapCopyPoints(polyf_brush.numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
 883         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
 884         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
 885         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brush, &polyf_brush);
 886 }
 887
 888 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, int q3surfaceflags, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 889 {
 890         int i;
 891         polyf_brush.numpoints = 3;
 892         polyf_brush.numplanes = 5;
 893         polyf_brush.points = polyf_points;
 894         polyf_brush.planes = polyf_planes;
 895         polyf_brush.supercontents = supercontents;
 896         for (i = 0;i < polyf_brush.numplanes;i++)
 897         {
 898                 polyf_brush.planes[i].q3surfaceflags = q3surfaceflags;
 899                 polyf_brush.planes[i].texture = texture;
 900         }
 901         for (i = 0;i < numtriangles;i++, element3i += 3)
 902         {
 903                 if (TriangleOverlapsBox(vertex3f + element3i[0]*3, vertex3f + element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
 904                 {
 905                         VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
 906                         VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
 907                         VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
 908                         Collision_SnapCopyPoints(polyf_brush.numpoints, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
 909                         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
 910                         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
 911                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brush, &polyf_brush);
 912                 }
 913         }
 914 }
 915
 916 void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numpoints, const float *points, int supercontents)
 917 {
 918         if (numpoints > 256)
 919         {
 920                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
 921                 return;
 922         }
 923         polyf_brush.numpoints = numpoints;
 924         polyf_brush.numplanes = numpoints + 2;
 925         //polyf_brush.points = (colpointf_t *)points;
 926         polyf_brush.points = polyf_points;
 927         Collision_SnapCopyPoints(polyf_brush.numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
 928         polyf_brush.planes = polyf_planes;
 929         polyf_brush.supercontents = supercontents;
 930         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
 931         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
 932         Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
 933 }
 934
 935 void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numtriangles, const int *element3i, const float *vertex3f, int supercontents, int q3surfaceflags, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 936 {
 937         int i;
 938 #if 1
 939         // FIXME: snap vertices?
 940         for (i = 0;i < numtriangles;i++, element3i += 3)
 941                 Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3, supercontents, q3surfaceflags, texture);
 942 #else
 943         polyf_brush.numpoints = 3;
 944         polyf_brush.numplanes = 5;
 945         polyf_brush.points = polyf_points;
 946         polyf_brush.planes = polyf_planes;
 947         polyf_brush.supercontents = supercontents;
 948         for (i = 0;i < polyf_brush.numplanes;i++)
 949         {
 950                 polyf_brush.planes[i].supercontents = supercontents;
 951                 polyf_brush.planes[i].q3surfaceflags = q3surfaceflags;
 952                 polyf_brush.planes[i].texture = texture;
 953         }
 954         for (i = 0;i < numtriangles;i++, element3i += 3)
 955         {
 956                 if (TriangleOverlapsBox(vertex3f + element3i[0]*3, vertex3 + [element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
 957                 {
 958                         VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
 959                         VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
 960                         VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
 961                         Collision_SnapCopyPoints(polyf_brush.numpoints, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
 962                         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
 963                         //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
 964                         Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
 965                 }
 966         }
 967 #endif
 968 }
 969
 970
 971 static colpointf_t polyf_pointsstart[256], polyf_pointsend[256];
 972 static colplanef_t polyf_planesstart[256 + 2], polyf_planesend[256 + 2];
 973 static colbrushf_t polyf_brushstart, polyf_brushend;
 974
 975 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, int q3surfaceflags, texture_t *texture)
 976 {
 977         int i;
 978         if (numpoints > 256)
 979         {
 980                 Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
 981                 return;
 982         }
 983         polyf_brushstart.numpoints = numpoints;
 984         polyf_brushstart.numplanes = numpoints + 2;
 985         polyf_brushstart.points = polyf_pointsstart;//(colpointf_t *)points;
 986         polyf_brushstart.planes = polyf_planesstart;
 987         polyf_brushstart.supercontents = supercontents;
 988         for (i = 0;i < numpoints;i++)
 989                 Matrix4x4_Transform(polygonmatrixstart, points + i * 3, polyf_brushstart.points[i].v);
 990         polyf_brushend.numpoints = numpoints;
 991         polyf_brushend.numplanes = numpoints + 2;
 992         polyf_brushend.points = polyf_pointsend;//(colpointf_t *)points;
 993         polyf_brushend.planes = polyf_planesend;
 994         polyf_brushend.supercontents = supercontents;
 995         for (i = 0;i < numpoints;i++)
 996                 Matrix4x4_Transform(polygonmatrixend, points + i * 3, polyf_brushend.points[i].v);
 997         for (i = 0;i < polyf_brushstart.numplanes;i++)
 998         {
 999                 polyf_brushstart.planes[i].q3surfaceflags = q3surfaceflags;
1000                 polyf_brushstart.planes[i].texture = texture;
1001         }
1002         Collision_SnapCopyPoints(polyf_brushstart.numpoints, polyf_pointsstart, polyf_pointsstart, COLLISION_SNAPSCALE, COLLISION_SNAP);
1003         Collision_SnapCopyPoints(polyf_brushend.numpoints, polyf_pointsend, polyf_pointsend, COLLISION_SNAPSCALE, COLLISION_SNAP);
1004         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushstart);
1005         Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushend);
1006
1007         //Collision_PrintBrushAsQHull(&polyf_brushstart, "polyf_brushstart");
1008         //Collision_PrintBrushAsQHull(&polyf_brushend, "polyf_brushend");
1009
1010         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brushstart, &polyf_brushend);
1011 }
1012
1013
1014
1015 #define MAX_BRUSHFORBOX 16
1016 static unsigned int brushforbox_index = 0;
1017 // note: this relies on integer overflow to be consistent with modulo
1018 // MAX_BRUSHFORBOX, or in other words, MAX_BRUSHFORBOX must be a power of two!
1019 static colpointf_t brushforbox_point[MAX_BRUSHFORBOX*8];
1020 static colplanef_t brushforbox_plane[MAX_BRUSHFORBOX*6];
1021 static colbrushf_t brushforbox_brush[MAX_BRUSHFORBOX];
1022 static colbrushf_t brushforpoint_brush[MAX_BRUSHFORBOX];
1023
1024 void Collision_InitBrushForBox(void)
1025 {
1026         int i;
1027         for (i = 0;i < MAX_BRUSHFORBOX;i++)
1028         {
1029                 brushforbox_brush[i].numpoints = 8;
1030                 brushforbox_brush[i].numplanes = 6;
1031                 brushforbox_brush[i].points = brushforbox_point + i * 8;
1032                 brushforbox_brush[i].planes = brushforbox_plane + i * 6;
1033                 brushforpoint_brush[i].numpoints = 1;
1034                 brushforpoint_brush[i].numplanes = 0;
1035                 brushforpoint_brush[i].points = brushforbox_point + i * 8;
1036                 brushforpoint_brush[i].planes = brushforbox_plane + i * 6;
1037         }
1038 }
1039
1040 colbrushf_t *Collision_BrushForBox(const matrix4x4_t *matrix, const vec3_t mins, const vec3_t maxs, int supercontents, int q3surfaceflags, texture_t *texture)
1041 {
1042         int i, j;
1043         vec3_t v;
1044         colbrushf_t *brush;
1045         if (brushforbox_brush[0].numpoints == 0)
1046                 Collision_InitBrushForBox();
1047         // FIXME: these probably don't actually need to be normalized if the collision code does not care
1048         if (VectorCompare(mins, maxs))
1049         {
1050                 // point brush
1051                 brush = brushforpoint_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
1052                 VectorCopy(mins, brush->points->v);
1053         }
1054         else
1055         {
1056                 brush = brushforbox_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
1057                 // FIXME: optimize
1058                 for (i = 0;i < 8;i++)
1059                 {
1060                         v[0] = i & 1 ? maxs[0] : mins[0];
1061                         v[1] = i & 2 ? maxs[1] : mins[1];
1062                         v[2] = i & 4 ? maxs[2] : mins[2];
1063                         Matrix4x4_Transform(matrix, v, brush->points[i].v);
1064                 }
1065                 // FIXME: optimize!
1066                 for (i = 0;i < 6;i++)
1067                 {
1068                         VectorClear(v);
1069                         v[i >> 1] = i & 1 ? 1 : -1;
1070                         Matrix4x4_Transform3x3(matrix, v, brush->planes[i].normal);
1071                         VectorNormalize(brush->planes[i].normal);
1072                 }
1073         }
1074         brush->supercontents = supercontents;
1075         for (j = 0;j < brush->numplanes;j++)
1076         {
1077                 brush->planes[j].q3surfaceflags = q3surfaceflags;
1078                 brush->planes[j].texture = texture;
1079                 brush->planes[j].dist = furthestplanedist_float(brush->planes[j].normal, brush->points, brush->numpoints);
1080         }
1081         VectorCopy(brush->points[0].v, brush->mins);
1082         VectorCopy(brush->points[0].v, brush->maxs);
1083         for (j = 1;j < brush->numpoints;j++)
1084         {
1085                 brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
1086                 brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
1087                 brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
1088                 brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
1089                 brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
1090                 brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
1091         }
1092         brush->mins[0] -= 1;
1093         brush->mins[1] -= 1;
1094         brush->mins[2] -= 1;
1095         brush->maxs[0] += 1;
1096         brush->maxs[1] += 1;
1097         brush->maxs[2] += 1;
1098         Collision_ValidateBrush(brush);
1099         return brush;
1100 }
1101
1102 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, int supercontents, int q3surfaceflags, texture_t *texture)
1103 {
1104         colbrushf_t *boxbrush, *thisbrush_start, *thisbrush_end;
1105         vec3_t startmins, startmaxs, endmins, endmaxs;
1106
1107         // create brushes for the collision
1108         VectorAdd(start, mins, startmins);
1109         VectorAdd(start, maxs, startmaxs);
1110         VectorAdd(end, mins, endmins);
1111         VectorAdd(end, maxs, endmaxs);
1112         boxbrush = Collision_BrushForBox(&identitymatrix, cmins, cmaxs, supercontents, q3surfaceflags, texture);
1113         thisbrush_start = Collision_BrushForBox(&identitymatrix, startmins, startmaxs, 0, 0, NULL);
1114         thisbrush_end = Collision_BrushForBox(&identitymatrix, endmins, endmaxs, 0, 0, NULL);
1115
1116         memset(trace, 0, sizeof(trace_t));
1117         trace->hitsupercontentsmask = hitsupercontentsmask;
1118         trace->fraction = 1;
1119         trace->realfraction = 1;
1120         trace->allsolid = true;
1121         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, boxbrush, boxbrush);
1122 }
1123
1124 //pseudocode for detecting line/sphere overlap without calculating an impact point
1125 //linesphereorigin = sphereorigin - linestart;linediff = lineend - linestart;linespherefrac = DotProduct(linesphereorigin, linediff) / DotProduct(linediff, linediff);return VectorLength2(linesphereorigin - bound(0, linespherefrac, 1) * linediff) >= sphereradius*sphereradius;
1126
1127 // LordHavoc: currently unused, but tested
1128 // note: this can be used for tracing a moving sphere vs a stationary sphere,
1129 // by simply adding the moving sphere's radius to the sphereradius parameter,
1130 // all the results are correct (impactpoint, impactnormal, and fraction)
1131 float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double *sphereorigin, double sphereradius, double *impactpoint, double *impactnormal)
1132 {
1133         double dir[3], scale, v[3], deviationdist, impactdist, linelength;
1134         // make sure the impactpoint and impactnormal are valid even if there is
1135         // no collision
1136         VectorCopy(lineend, impactpoint);
1137         VectorClear(impactnormal);
1138         // calculate line direction
1139         VectorSubtract(lineend, linestart, dir);
1140         // normalize direction
1141         linelength = VectorLength(dir);
1142         if (linelength)
1143         {
1144                 scale = 1.0 / linelength;
1145                 VectorScale(dir, scale, dir);
1146         }
1147         // this dotproduct calculates the distance along the line at which the
1148         // sphere origin is (nearest point to the sphere origin on the line)
1149         impactdist = DotProduct(sphereorigin, dir) - DotProduct(linestart, dir);
1150         // calculate point on line at that distance, and subtract the
1151         // sphereorigin from it, so we have a vector to measure for the distance
1152         // of the line from the sphereorigin (deviation, how off-center it is)
1153         VectorMA(linestart, impactdist, dir, v);
1154         VectorSubtract(v, sphereorigin, v);
1155         deviationdist = VectorLength2(v);
1156         // if outside the radius, it's a miss for sure
1157         // (we do this comparison using squared radius to avoid a sqrt)
1158         if (deviationdist > sphereradius*sphereradius)
1159                 return 1; // miss (off to the side)
1160         // nudge back to find the correct impact distance
1161         impactdist -= sphereradius - deviationdist/sphereradius;
1162         if (impactdist >= linelength)
1163                 return 1; // miss (not close enough)
1164         if (impactdist < 0)
1165                 return 1; // miss (linestart is past or inside sphere)
1166         // calculate new impactpoint
1167         VectorMA(linestart, impactdist, dir, impactpoint);
1168         // calculate impactnormal (surface normal at point of impact)
1169         VectorSubtract(impactpoint, sphereorigin, impactnormal);
1170         // normalize impactnormal
1171         VectorNormalize(impactnormal);
1172         // return fraction of movement distance
1173         return impactdist / linelength;
1174 }
1175
1176 void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const float *point0, const float *point1, const float *point2, int supercontents, int q3surfaceflags, texture_t *texture)
1177 {
1178 #if 1
1179         // more optimized
1180         float d1, d2, d, f, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
1181
1182         // this function executes:
1183         // 32 ops when line starts behind triangle
1184         // 38 ops when line ends infront of triangle
1185         // 43 ops when line fraction is already closer than this triangle
1186         // 72 ops when line is outside edge 01
1187         // 92 ops when line is outside edge 21
1188         // 115 ops when line is outside edge 02
1189         // 123 ops when line impacts triangle and updates trace results
1190
1191         // this code is designed for clockwise triangles, conversion to
1192         // counterclockwise would require swapping some things around...
1193         // it is easier to simply swap the point0 and point2 parameters to this
1194         // function when calling it than it is to rewire the internals.
1195
1196         // calculate the faceplanenormal of the triangle, this represents the front side
1197         // 15 ops
1198         VectorSubtract(point0, point1, edge01);
1199         VectorSubtract(point2, point1, edge21);
1200         CrossProduct(edge01, edge21, faceplanenormal);
1201         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
1202         // 6 ops
1203         faceplanenormallength2 = DotProduct(faceplanenormal, faceplanenormal);
1204         if (faceplanenormallength2 < 0.0001f)
1205                 return;
1206         // calculate the distance
1207         // 5 ops
1208         faceplanedist = DotProduct(point0, faceplanenormal);
1209
1210         // if start point is on the back side there is no collision
1211         // (we don't care about traces going through the triangle the wrong way)
1212
1213         // calculate the start distance
1214         // 6 ops
1215         d1 = DotProduct(faceplanenormal, linestart);
1216         if (d1 <= faceplanedist)
1217                 return;
1218
1219         // calculate the end distance
1220         // 6 ops
1221         d2 = DotProduct(faceplanenormal, lineend);
1222         // if both are in front, there is no collision
1223         if (d2 >= faceplanedist)
1224                 return;
1225
1226         // from here on we know d1 is >= 0 and d2 is < 0
1227         // this means the line starts infront and ends behind, passing through it
1228
1229         // calculate the recipricol of the distance delta,
1230         // so we can use it multiple times cheaply (instead of division)
1231         // 2 ops
1232         d = 1.0f / (d1 - d2);
1233         // calculate the impact fraction by taking the start distance (> 0)
1234         // and subtracting the face plane distance (this is the distance of the
1235         // triangle along that same normal)
1236         // then multiply by the recipricol distance delta
1237         // 2 ops
1238         f = (d1 - faceplanedist) * d;
1239         // skip out if this impact is further away than previous ones
1240         // 1 ops
1241         if (f > trace->realfraction)
1242                 return;
1243         // calculate the perfect impact point for classification of insidedness
1244         // 9 ops
1245         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1246         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1247         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1248
1249         // calculate the edge normal and reject if impact is outside triangle
1250         // (an edge normal faces away from the triangle, to get the desired normal
1251         //  a crossproduct with the faceplanenormal is used, and because of the way
1252         // the insidedness comparison is written it does not need to be normalized)
1253
1254         // first use the two edges from the triangle plane math
1255         // the other edge only gets calculated if the point survives that long
1256
1257         // 20 ops
1258         CrossProduct(edge01, faceplanenormal, edgenormal);
1259         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1260                 return;
1261
1262         // 20 ops
1263         CrossProduct(faceplanenormal, edge21, edgenormal);
1264         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1265                 return;
1266
1267         // 23 ops
1268         VectorSubtract(point0, point2, edge02);
1269         CrossProduct(faceplanenormal, edge02, edgenormal);
1270         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1271                 return;
1272
1273         // 8 ops (rare)
1274
1275         // store the new trace fraction
1276         trace->realfraction = f;
1277
1278         // calculate a nudged fraction to keep it out of the surface
1279         // (the main fraction remains perfect)
1280         trace->fraction = f - collision_impactnudge.value * d;
1281
1282         if (collision_prefernudgedfraction.integer)
1283                 trace->realfraction = trace->fraction;
1284
1285         // store the new trace plane (because collisions only happen from
1286         // the front this is always simply the triangle normal, never flipped)
1287         d = 1.0 / sqrt(faceplanenormallength2);
1288         VectorScale(faceplanenormal, d, trace->plane.normal);
1289         trace->plane.dist = faceplanedist * d;
1290
1291         trace->hitsupercontents = supercontents;
1292         trace->hitq3surfaceflags = q3surfaceflags;
1293         trace->hittexture = texture;
1294 #else
1295         float d1, d2, d, f, fnudged, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, edge[3];
1296
1297         // this code is designed for clockwise triangles, conversion to
1298         // counterclockwise would require swapping some things around...
1299         // it is easier to simply swap the point0 and point2 parameters to this
1300         // function when calling it than it is to rewire the internals.
1301
1302         // calculate the unnormalized faceplanenormal of the triangle,
1303         // this represents the front side
1304         TriangleNormal(point0, point1, point2, faceplanenormal);
1305         // there's no point in processing a degenerate triangle
1306         // (GIGO - Garbage In, Garbage Out)
1307         if (DotProduct(faceplanenormal, faceplanenormal) < 0.0001f)
1308                 return;
1309         // calculate the unnormalized distance
1310         faceplanedist = DotProduct(point0, faceplanenormal);
1311
1312         // calculate the unnormalized start distance
1313         d1 = DotProduct(faceplanenormal, linestart) - faceplanedist;
1314         // if start point is on the back side there is no collision
1315         // (we don't care about traces going through the triangle the wrong way)
1316         if (d1 <= 0)
1317                 return;
1318
1319         // calculate the unnormalized end distance
1320         d2 = DotProduct(faceplanenormal, lineend) - faceplanedist;
1321         // if both are in front, there is no collision
1322         if (d2 >= 0)
1323                 return;
1324
1325         // from here on we know d1 is >= 0 and d2 is < 0
1326         // this means the line starts infront and ends behind, passing through it
1327
1328         // calculate the recipricol of the distance delta,
1329         // so we can use it multiple times cheaply (instead of division)
1330         d = 1.0f / (d1 - d2);
1331         // calculate the impact fraction by taking the start distance (> 0)
1332         // and subtracting the face plane distance (this is the distance of the
1333         // triangle along that same normal)
1334         // then multiply by the recipricol distance delta
1335         f = d1 * d;
1336         // skip out if this impact is further away than previous ones
1337         if (f > trace->realfraction)
1338                 return;
1339         // calculate the perfect impact point for classification of insidedness
1340         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1341         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1342         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1343
1344         // calculate the edge normal and reject if impact is outside triangle
1345         // (an edge normal faces away from the triangle, to get the desired normal
1346         //  a crossproduct with the faceplanenormal is used, and because of the way
1347         // the insidedness comparison is written it does not need to be normalized)
1348
1349         VectorSubtract(point2, point0, edge);
1350         CrossProduct(edge, faceplanenormal, edgenormal);
1351         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1352                 return;
1353
1354         VectorSubtract(point0, point1, edge);
1355         CrossProduct(edge, faceplanenormal, edgenormal);
1356         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1357                 return;
1358
1359         VectorSubtract(point1, point2, edge);
1360         CrossProduct(edge, faceplanenormal, edgenormal);
1361         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1362                 return;
1363
1364         // store the new trace fraction
1365         trace->realfraction = bound(0, f, 1);
1366
1367         // store the new trace plane (because collisions only happen from
1368         // the front this is always simply the triangle normal, never flipped)
1369         VectorNormalize(faceplanenormal);
1370         VectorCopy(faceplanenormal, trace->plane.normal);
1371         trace->plane.dist = DotProduct(point0, faceplanenormal);
1372
1373         // calculate the normalized start and end distances
1374         d1 = DotProduct(trace->plane.normal, linestart) - trace->plane.dist;
1375         d2 = DotProduct(trace->plane.normal, lineend) - trace->plane.dist;
1376
1377         // calculate a nudged fraction to keep it out of the surface
1378         // (the main fraction remains perfect)
1379         fnudged = (d1 - collision_impactnudge.value) / (d1 - d2);
1380         trace->fraction = bound(0, fnudged, 1);
1381
1382         // store the new trace endpos
1383         // not needed, it's calculated later when the trace is finished
1384         //trace->endpos[0] = linestart[0] + fnudged * (lineend[0] - linestart[0]);
1385         //trace->endpos[1] = linestart[1] + fnudged * (lineend[1] - linestart[1]);
1386         //trace->endpos[2] = linestart[2] + fnudged * (lineend[2] - linestart[2]);
1387         trace->hitsupercontents = supercontents;
1388         trace->hitq3surfaceflags = q3surfaceflags;
1389         trace->hittexture = texture;
1390 #endif
1391 }
1392
1393 typedef struct colbspnode_s
1394 {
1395         mplane_t plane;
1396         struct colbspnode_s *children[2];
1397         // the node is reallocated or split if max is reached
1398         int numcolbrushf;
1399         int maxcolbrushf;
1400         colbrushf_t **colbrushflist;
1401         //int numcolbrushd;
1402         //int maxcolbrushd;
1403         //colbrushd_t **colbrushdlist;
1404 }
1405 colbspnode_t;
1406
1407 typedef struct colbsp_s
1408 {
1409         mempool_t *mempool;
1410         colbspnode_t *nodes;
1411 }
1412 colbsp_t;
1413
1414 colbsp_t *Collision_CreateCollisionBSP(mempool_t *mempool)
1415 {
1416         colbsp_t *bsp;
1417         bsp = (colbsp_t *)Mem_Alloc(mempool, sizeof(colbsp_t));
1418         bsp->mempool = mempool;
1419         bsp->nodes = (colbspnode_t *)Mem_Alloc(bsp->mempool, sizeof(colbspnode_t));
1420         return bsp;
1421 }
1422
1423 void Collision_FreeCollisionBSPNode(colbspnode_t *node)
1424 {
1425         if (node->children[0])
1426                 Collision_FreeCollisionBSPNode(node->children[0]);
1427         if (node->children[1])
1428                 Collision_FreeCollisionBSPNode(node->children[1]);
1429         while (--node->numcolbrushf)
1430                 Mem_Free(node->colbrushflist[node->numcolbrushf]);
1431         //while (--node->numcolbrushd)
1432         //      Mem_Free(node->colbrushdlist[node->numcolbrushd]);
1433         Mem_Free(node);
1434 }
1435
1436 void Collision_FreeCollisionBSP(colbsp_t *bsp)
1437 {
1438         Collision_FreeCollisionBSPNode(bsp->nodes);
1439         Mem_Free(bsp);
1440 }
1441
1442 void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const colbrushf_t *end, vec3_t mins, vec3_t maxs, float startfrac, float endfrac)
1443 {
1444         int i;
1445         colpointf_t *ps, *pe;
1446         float tempstart[3], tempend[3];
1447         VectorLerp(start->points[0].v, startfrac, end->points[0].v, mins);
1448         VectorCopy(mins, maxs);
1449         for (i = 0, ps = start->points, pe = end->points;i < start->numpoints;i++, ps++, pe++)
1450         {
1451                 VectorLerp(ps->v, startfrac, pe->v, tempstart);
1452                 VectorLerp(ps->v, endfrac, pe->v, tempend);
1453                 mins[0] = min(mins[0], min(tempstart[0], tempend[0]));
1454                 mins[1] = min(mins[1], min(tempstart[1], tempend[1]));
1455                 mins[2] = min(mins[2], min(tempstart[2], tempend[2]));
1456                 maxs[0] = min(maxs[0], min(tempstart[0], tempend[0]));
1457                 maxs[1] = min(maxs[1], min(tempstart[1], tempend[1]));
1458                 maxs[2] = min(maxs[2], min(tempstart[2], tempend[2]));
1459         }
1460         mins[0] -= 1;
1461         mins[1] -= 1;
1462         mins[2] -= 1;
1463         maxs[0] += 1;
1464         maxs[1] += 1;
1465         maxs[2] += 1;
1466 }
1467
1468 //===========================================
1469
1470 void Collision_ClipToGenericEntity(trace_t *trace, dp_model_t *model, int frame, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask)
1471 {
1472         float starttransformed[3], endtransformed[3];
1473
1474         memset(trace, 0, sizeof(*trace));
1475         trace->fraction = trace->realfraction = 1;
1476         VectorCopy(end, trace->endpos);
1477
1478         Matrix4x4_Transform(inversematrix, start, starttransformed);
1479         Matrix4x4_Transform(inversematrix, end, endtransformed);
1480 #if COLLISIONPARANOID >= 3
1481         Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", start[0], start[1], start[2], starttransformed[0], starttransformed[1], starttransformed[2], end[0], end[1], end[2], endtransformed[0], endtransformed[1], endtransformed[2]);
1482 #endif
1483
1484         if (model && model->TraceBox)
1485                 model->TraceBox(model, bound(0, frame, (model->numframes - 1)), trace, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask);
1486         else
1487                 Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1488         trace->fraction = bound(0, trace->fraction, 1);
1489         trace->realfraction = bound(0, trace->realfraction, 1);
1490
1491         VectorLerp(start, trace->fraction, end, trace->endpos);
1492         // transform plane
1493         // NOTE: this relies on plane.dist being directly after plane.normal
1494         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1495 }
1496
1497 void Collision_ClipToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontents)
1498 {
1499         memset(trace, 0, sizeof(*trace));
1500         trace->fraction = trace->realfraction = 1;
1501         if (model && model->TraceBox)
1502                 model->TraceBox(model, 0, trace, start, mins, maxs, end, hitsupercontents);
1503         trace->fraction = bound(0, trace->fraction, 1);
1504         trace->realfraction = bound(0, trace->realfraction, 1);
1505         VectorLerp(start, trace->fraction, end, trace->endpos);
1506 }
1507
1508 void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *touch, qboolean isbmodel)
1509 {
1510         // take the 'best' answers from the new trace and combine with existing data
1511         if (trace->allsolid)
1512                 cliptrace->allsolid = true;
1513         if (trace->startsolid)
1514         {
1515                 if (isbmodel)
1516                         cliptrace->bmodelstartsolid = true;
1517                 cliptrace->startsolid = true;
1518                 if (cliptrace->realfraction == 1)
1519                         cliptrace->ent = touch;
1520         }
1521         // don't set this except on the world, because it can easily confuse
1522         // monsters underwater if there's a bmodel involved in the trace
1523         // (inopen && inwater is how they check water visibility)
1524         //if (trace->inopen)
1525         //      cliptrace->inopen = true;
1526         if (trace->inwater)
1527                 cliptrace->inwater = true;
1528         if (trace->realfraction <= cliptrace->realfraction)
1529         {
1530                 cliptrace->fraction = trace->fraction;
1531                 cliptrace->realfraction = trace->realfraction;
1532                 VectorCopy(trace->endpos, cliptrace->endpos);
1533                 cliptrace->plane = trace->plane;
1534                 cliptrace->ent = touch;
1535                 cliptrace->hitsupercontents = trace->hitsupercontents;
1536                 cliptrace->hitq3surfaceflags = trace->hitq3surfaceflags;
1537                 cliptrace->hittexture = trace->hittexture;
1538         }
1539         cliptrace->startsupercontents |= trace->startsupercontents;
1540 }