collision.c

   1
   2 #include "quakedef.h"
   3 #include "polygon.h"
   4
   5 #define COLLISION_EDGEDIR_DOT_EPSILON (0.999f)
   6 #define COLLISION_EDGECROSS_MINLENGTH2 (1.0f / 4194304.0f)
   7 #define COLLISION_SNAPSCALE (32.0f)
   8 #define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
   9 #define COLLISION_SNAP2 (2.0f / COLLISION_SNAPSCALE)
  10 #define COLLISION_PLANE_DIST_EPSILON (2.0f / COLLISION_SNAPSCALE)
  11
  12 cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125", "how much to back off from the impact"};
  13 cvar_t collision_extendmovelength = {0, "collision_extendmovelength", "16", "internal bias on trace length to ensure detection of collisions within the collision_impactnudge distance so that short moves do not degrade across frames (this does not alter the final trace length)"};
  14 cvar_t collision_extendtraceboxlength = {0, "collision_extendtraceboxlength", "1", "internal bias for tracebox() qc builtin to account for collision_impactnudge (this does not alter the final trace length)"};
  15 cvar_t collision_extendtracelinelength = {0, "collision_extendtracelinelength", "1", "internal bias for traceline() qc builtin to account for collision_impactnudge (this does not alter the final trace length)"};
  16 cvar_t collision_debug_tracelineasbox = {0, "collision_debug_tracelineasbox", "0", "workaround for any bugs in Collision_TraceLineBrushFloat by using Collision_TraceBrushBrushFloat"};
  17 cvar_t collision_cache = {0, "collision_cache", "1", "store results of collision traces for next frame to reuse if possible (optimization)"};
  18 //cvar_t collision_triangle_neighborsides = {0, "collision_triangle_neighborsides", "1", "override automatic side generation if triangle has neighbors with face planes that form a convex edge (perfect solution, but can not work for all edges)"};
  19 cvar_t collision_triangle_bevelsides = {0, "collision_triangle_bevelsides", "0", "generate sloped edge planes on triangles - if 0, see axialedgeplanes"};
  20 cvar_t collision_triangle_axialsides = {0, "collision_triangle_axialsides", "1", "generate axially-aligned edge planes on triangles - otherwise use perpendicular edge planes"};
  21
  22 mempool_t *collision_mempool;
  23
  24 void Collision_Init (void)
  25 {
  26         Cvar_RegisterVariable(&collision_impactnudge);
  27         Cvar_RegisterVariable(&collision_extendmovelength);
  28         Cvar_RegisterVariable(&collision_extendtracelinelength);
  29         Cvar_RegisterVariable(&collision_extendtraceboxlength);
  30         Cvar_RegisterVariable(&collision_debug_tracelineasbox);
  31         Cvar_RegisterVariable(&collision_cache);
  32 //      Cvar_RegisterVariable(&collision_triangle_neighborsides);
  33         Cvar_RegisterVariable(&collision_triangle_bevelsides);
  34         Cvar_RegisterVariable(&collision_triangle_axialsides);
  35         collision_mempool = Mem_AllocPool("collision cache", 0, NULL);
  36         Collision_Cache_Init(collision_mempool);
  37 }
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52 static void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
  53 {
  54         int i;
  55         Con_Printf("3 %s\n%i\n", name, brush->numpoints);
  56         for (i = 0;i < brush->numpoints;i++)
  57                 Con_Printf("%f %f %f\n", brush->points[i].v[0], brush->points[i].v[1], brush->points[i].v[2]);
  58         // FIXME: optimize!
  59         Con_Printf("4\n%i\n", brush->numplanes);
  60         for (i = 0;i < brush->numplanes;i++)
  61                 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);
  62 }
  63
  64 static void Collision_ValidateBrush(colbrushf_t *brush)
  65 {
  66         int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
  67         float d;
  68         printbrush = false;
  69         if (!brush->numpoints)
  70         {
  71                 Con_Print("Collision_ValidateBrush: brush with no points!\n");
  72                 printbrush = true;
  73         }
  74 #if 0
  75         // it's ok for a brush to have one point and no planes...
  76         if (brush->numplanes == 0 && brush->numpoints != 1)
  77         {
  78                 Con_Print("Collision_ValidateBrush: brush with no planes and more than one point!\n");
  79                 printbrush = true;
  80         }
  81 #endif
  82         if (brush->numplanes)
  83         {
  84                 pointsoffplanes = 0;
  85                 pointswithinsufficientplanes = 0;
  86                 for (k = 0;k < brush->numplanes;k++)
  87                         if (DotProduct(brush->planes[k].normal, brush->planes[k].normal) < 0.0001f)
  88                                 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);
  89                 for (j = 0;j < brush->numpoints;j++)
  90                 {
  91                         pointonplanes = 0;
  92                         for (k = 0;k < brush->numplanes;k++)
  93                         {
  94                                 d = DotProduct(brush->points[j].v, brush->planes[k].normal) - brush->planes[k].dist;
  95                                 if (d > COLLISION_PLANE_DIST_EPSILON)
  96                                 {
  97                                         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);
  98                                         printbrush = true;
  99                                 }
 100                                 if (fabs(d) > COLLISION_PLANE_DIST_EPSILON)
 101                                         pointsoffplanes++;
 102                                 else
 103                                         pointonplanes++;
 104                         }
 105                         if (pointonplanes < 3)
 106                                 pointswithinsufficientplanes++;
 107                 }
 108                 if (pointswithinsufficientplanes)
 109                 {
 110                         Con_Print("Collision_ValidateBrush: some points have insufficient planes, every point must be on at least 3 planes to form a corner.\n");
 111                         printbrush = true;
 112                 }
 113                 if (pointsoffplanes == 0) // all points are on all planes
 114                 {
 115                         Con_Print("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
 116                         printbrush = true;
 117                 }
 118         }
 119         if (printbrush)
 120                 Collision_PrintBrushAsQHull(brush, "unnamed");
 121 }
 122
 123 static float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 124 {
 125         float dist, bestdist;
 126         if (!numpoints)
 127                 return 0;
 128         bestdist = DotProduct(points->v, normal);
 129         points++;
 130         while(--numpoints)
 131         {
 132                 dist = DotProduct(points->v, normal);
 133                 bestdist = min(bestdist, dist);
 134                 points++;
 135         }
 136         return bestdist;
 137 }
 138
 139 static float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 140 {
 141         float dist, bestdist;
 142         if (!numpoints)
 143                 return 0;
 144         bestdist = DotProduct(points->v, normal);
 145         points++;
 146         while(--numpoints)
 147         {
 148                 dist = DotProduct(points->v, normal);
 149                 bestdist = max(bestdist, dist);
 150                 points++;
 151         }
 152         return bestdist;
 153 }
 154
 155 static void Collision_CalcEdgeDirsForPolygonBrushFloat(colbrushf_t *brush)
 156 {
 157         int i, j;
 158         for (i = 0, j = brush->numpoints - 1;i < brush->numpoints;j = i, i++)
 159                 VectorSubtract(brush->points[i].v, brush->points[j].v, brush->edgedirs[j].v);
 160 }
 161
 162 colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const colplanef_t *originalplanes, int supercontents, int q3surfaceflags, const texture_t *texture, int hasaabbplanes)
 163 {
 164         // TODO: planesbuf could be replaced by a remapping table
 165         int j, k, l, m, w, xyzflags;
 166         int numpointsbuf = 0, maxpointsbuf = 256, numedgedirsbuf = 0, maxedgedirsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
 167         int isaabb = true;
 168         double maxdist;
 169         colbrushf_t *brush;
 170         colpointf_t pointsbuf[256];
 171         colpointf_t edgedirsbuf[256];
 172         colplanef_t planesbuf[256];
 173         int elementsbuf[1024];
 174         int polypointbuf[256];
 175         int pmaxpoints = 64;
 176         int pnumpoints;
 177         double p[2][3*64];
 178 #if 0
 179         // enable these if debugging to avoid seeing garbage in unused data-
 180         memset(pointsbuf, 0, sizeof(pointsbuf));
 181         memset(edgedirsbuf, 0, sizeof(edgedirsbuf));
 182         memset(planesbuf, 0, sizeof(planesbuf));
 183         memset(elementsbuf, 0, sizeof(elementsbuf));
 184         memset(polypointbuf, 0, sizeof(polypointbuf));
 185         memset(p, 0, sizeof(p));
 186 #endif
 187
 188         // check if there are too many planes and skip the brush
 189         if (numoriginalplanes >= maxplanesbuf)
 190         {
 191                 Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
 192                 return NULL;
 193         }
 194
 195         // figure out how large a bounding box we need to properly compute this brush
 196         maxdist = 0;
 197         for (j = 0;j < numoriginalplanes;j++)
 198                 maxdist = max(maxdist, fabs(originalplanes[j].dist));
 199         // now make it large enough to enclose the entire brush, and round it off to a reasonable multiple of 1024
 200         maxdist = floor(maxdist * (4.0 / 1024.0) + 2) * 1024.0;
 201         // construct a collision brush (points, planes, and renderable mesh) from
 202         // a set of planes, this also optimizes out any unnecessary planes (ones
 203         // whose polygon is clipped away by the other planes)
 204         for (j = 0;j < numoriginalplanes;j++)
 205         {
 206                 // add the new plane
 207                 VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
 208                 planesbuf[numplanesbuf].dist = originalplanes[j].dist;
 209                 planesbuf[numplanesbuf].q3surfaceflags = originalplanes[j].q3surfaceflags;
 210                 planesbuf[numplanesbuf].texture = originalplanes[j].texture;
 211                 numplanesbuf++;
 212
 213                 // create a large polygon from the plane
 214                 w = 0;
 215                 PolygonD_QuadForPlane(p[w], originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist, maxdist);
 216                 pnumpoints = 4;
 217                 // clip it by all other planes
 218                 for (k = 0;k < numoriginalplanes && pnumpoints >= 3 && pnumpoints <= pmaxpoints;k++)
 219                 {
 220                         // skip the plane this polygon
 221                         // (nothing happens if it is processed, this is just an optimization)
 222                         if (k != j)
 223                         {
 224                                 // we want to keep the inside of the brush plane so we flip
 225                                 // the cutting plane
 226                                 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);
 227                                 w = !w;
 228                         }
 229                 }
 230
 231                 // if nothing is left, skip it
 232                 if (pnumpoints < 3)
 233                 {
 234                         //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);
 235                         continue;
 236                 }
 237
 238                 for (k = 0;k < pnumpoints;k++)
 239                 {
 240                         int l, m;
 241                         m = 0;
 242                         for (l = 0;l < numoriginalplanes;l++)
 243                                 if (fabs(DotProduct(&p[w][k*3], originalplanes[l].normal) - originalplanes[l].dist) < COLLISION_PLANE_DIST_EPSILON)
 244                                         m++;
 245                         if (m < 3)
 246                                 break;
 247                 }
 248                 if (k < pnumpoints)
 249                 {
 250                         Con_DPrintf("Collision_NewBrushFromPlanes: warning: polygon point does not lie on at least 3 planes\n");
 251                         //return NULL;
 252                 }
 253
 254                 // check if there are too many polygon vertices for buffer
 255                 if (pnumpoints > pmaxpoints)
 256                 {
 257                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 258                         return NULL;
 259                 }
 260
 261                 // check if there are too many triangle elements for buffer
 262                 if (numelementsbuf + (pnumpoints - 2) * 3 > maxelementsbuf)
 263                 {
 264                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
 265                         return NULL;
 266                 }
 267
 268                 // add the unique points for this polygon
 269                 for (k = 0;k < pnumpoints;k++)
 270                 {
 271                         float v[3];
 272                         // downgrade to float precision before comparing
 273                         VectorCopy(&p[w][k*3], v);
 274
 275                         // check if there is already a matching point (no duplicates)
 276                         for (m = 0;m < numpointsbuf;m++)
 277                                 if (VectorDistance2(v, pointsbuf[m].v) < COLLISION_SNAP2)
 278                                         break;
 279
 280                         // if there is no match, add a new one
 281                         if (m == numpointsbuf)
 282                         {
 283                                 // check if there are too many and skip the brush
 284                                 if (numpointsbuf >= maxpointsbuf)
 285                                 {
 286                                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 287                                         return NULL;
 288                                 }
 289                                 // add the new one
 290                                 VectorCopy(&p[w][k*3], pointsbuf[numpointsbuf].v);
 291                                 numpointsbuf++;
 292                         }
 293
 294                         // store the index into a buffer
 295                         polypointbuf[k] = m;
 296                 }
 297
 298                 // add the triangles for the polygon
 299                 // (this particular code makes a triangle fan)
 300                 for (k = 0;k < pnumpoints - 2;k++)
 301                 {
 302                         elementsbuf[numelementsbuf++] = polypointbuf[0];
 303                         elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
 304                         elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
 305                 }
 306
 307                 // add the unique edgedirs for this polygon
 308                 for (k = 0, l = pnumpoints-1;k < pnumpoints;l = k, k++)
 309                 {
 310                         float dir[3];
 311                         // downgrade to float precision before comparing
 312                         VectorSubtract(&p[w][k*3], &p[w][l*3], dir);
 313                         VectorNormalize(dir);
 314
 315                         // check if there is already a matching edgedir (no duplicates)
 316                         for (m = 0;m < numedgedirsbuf;m++)
 317                                 if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
 318                                         break;
 319                         // skip this if there is
 320                         if (m < numedgedirsbuf)
 321                                 continue;
 322
 323                         // try again with negated edgedir
 324                         VectorNegate(dir, dir);
 325                         // check if there is already a matching edgedir (no duplicates)
 326                         for (m = 0;m < numedgedirsbuf;m++)
 327                                 if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
 328                                         break;
 329                         // if there is no match, add a new one
 330                         if (m == numedgedirsbuf)
 331                         {
 332                                 // check if there are too many and skip the brush
 333                                 if (numedgedirsbuf >= maxedgedirsbuf)
 334                                 {
 335                                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many edgedirs for buffer\n");
 336                                         return NULL;
 337                                 }
 338                                 // add the new one
 339                                 VectorCopy(dir, edgedirsbuf[numedgedirsbuf].v);
 340                                 numedgedirsbuf++;
 341                         }
 342                 }
 343
 344                 // if any normal is not purely axial, it's not an axis-aligned box
 345                 if (isaabb && (originalplanes[j].normal[0] == 0) + (originalplanes[j].normal[1] == 0) + (originalplanes[j].normal[2] == 0) < 2)
 346                         isaabb = false;
 347         }
 348
 349         // if nothing is left, there's nothing to allocate
 350         if (numplanesbuf < 4)
 351         {
 352                 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);
 353                 return NULL;
 354         }
 355
 356         // if no triangles or points could be constructed, then this routine failed but the brush is not discarded
 357         if (numelementsbuf < 12 || numpointsbuf < 4)
 358                 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);
 359
 360         // validate plane distances
 361         for (j = 0;j < numplanesbuf;j++)
 362         {
 363                 float d = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpointsbuf);
 364                 if (fabs(planesbuf[j].dist - d) > COLLISION_PLANE_DIST_EPSILON)
 365                         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);
 366         }
 367
 368         // allocate the brush and copy to it
 369         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpointsbuf + sizeof(colpointf_t) * numedgedirsbuf + sizeof(colplanef_t) * numplanesbuf + sizeof(int) * numelementsbuf);
 370         brush->isaabb = isaabb;
 371         brush->hasaabbplanes = hasaabbplanes;
 372         brush->supercontents = supercontents;
 373         brush->numplanes = numplanesbuf;
 374         brush->numedgedirs = numedgedirsbuf;
 375         brush->numpoints = numpointsbuf;
 376         brush->numtriangles = numelementsbuf / 3;
 377         brush->planes = (colplanef_t *)(brush + 1);
 378         brush->points = (colpointf_t *)(brush->planes + brush->numplanes);
 379         brush->edgedirs = (colpointf_t *)(brush->points + brush->numpoints);
 380         brush->elements = (int *)(brush->points + brush->numpoints);
 381         brush->q3surfaceflags = q3surfaceflags;
 382         brush->texture = texture;
 383         for (j = 0;j < brush->numpoints;j++)
 384         {
 385                 brush->points[j].v[0] = pointsbuf[j].v[0];
 386                 brush->points[j].v[1] = pointsbuf[j].v[1];
 387                 brush->points[j].v[2] = pointsbuf[j].v[2];
 388         }
 389         for (j = 0;j < brush->numedgedirs;j++)
 390         {
 391                 brush->edgedirs[j].v[0] = edgedirsbuf[j].v[0];
 392                 brush->edgedirs[j].v[1] = edgedirsbuf[j].v[1];
 393                 brush->edgedirs[j].v[2] = edgedirsbuf[j].v[2];
 394         }
 395         for (j = 0;j < brush->numplanes;j++)
 396         {
 397                 brush->planes[j].normal[0] = planesbuf[j].normal[0];
 398                 brush->planes[j].normal[1] = planesbuf[j].normal[1];
 399                 brush->planes[j].normal[2] = planesbuf[j].normal[2];
 400                 brush->planes[j].dist = planesbuf[j].dist;
 401                 brush->planes[j].q3surfaceflags = planesbuf[j].q3surfaceflags;
 402                 brush->planes[j].texture = planesbuf[j].texture;
 403         }
 404         for (j = 0;j < brush->numtriangles * 3;j++)
 405                 brush->elements[j] = elementsbuf[j];
 406
 407         xyzflags = 0;
 408         VectorClear(brush->mins);
 409         VectorClear(brush->maxs);
 410         for (j = 0;j < min(6, numoriginalplanes);j++)
 411         {
 412                      if (originalplanes[j].normal[0] ==  1) {xyzflags |=  1;brush->maxs[0] =  originalplanes[j].dist;}
 413                 else if (originalplanes[j].normal[0] == -1) {xyzflags |=  2;brush->mins[0] = -originalplanes[j].dist;}
 414                 else if (originalplanes[j].normal[1] ==  1) {xyzflags |=  4;brush->maxs[1] =  originalplanes[j].dist;}
 415                 else if (originalplanes[j].normal[1] == -1) {xyzflags |=  8;brush->mins[1] = -originalplanes[j].dist;}
 416                 else if (originalplanes[j].normal[2] ==  1) {xyzflags |= 16;brush->maxs[2] =  originalplanes[j].dist;}
 417                 else if (originalplanes[j].normal[2] == -1) {xyzflags |= 32;brush->mins[2] = -originalplanes[j].dist;}
 418         }
 419         // if not all xyzflags were set, then this is not a brush from q3map/q3map2, and needs reconstruction of the bounding box
 420         // (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)
 421         if (xyzflags != 63)
 422         {
 423                 VectorCopy(brush->points[0].v, brush->mins);
 424                 VectorCopy(brush->points[0].v, brush->maxs);
 425                 for (j = 1;j < brush->numpoints;j++)
 426                 {
 427                         brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
 428                         brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
 429                         brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
 430                         brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
 431                         brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
 432                         brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
 433                 }
 434         }
 435         brush->mins[0] -= 1;
 436         brush->mins[1] -= 1;
 437         brush->mins[2] -= 1;
 438         brush->maxs[0] += 1;
 439         brush->maxs[1] += 1;
 440         brush->maxs[2] += 1;
 441         Collision_ValidateBrush(brush);
 442         return brush;
 443 }
 444
 445
 446
 447 void Collision_CalcPlanesForTriangleBrushFloat(colbrushf_t *brush)
 448 {
 449         int i;
 450         float edge0[3], edge1[3], edge2[3];
 451         colpointf_t *p;
 452
 453         TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
 454         if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
 455         {
 456                 // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 457                 // note that some of these exist in q3bsp bspline patches
 458                 brush->numplanes = 0;
 459                 return;
 460         }
 461
 462         // there are 5 planes (front, back, sides) and 3 edges
 463         brush->numplanes = 5;
 464         brush->numedgedirs = 3;
 465         VectorNormalize(brush->planes[0].normal);
 466         brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
 467         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 468         brush->planes[1].dist = -brush->planes[0].dist;
 469         // edge directions are easy to calculate
 470         VectorSubtract(brush->points[2].v, brush->points[0].v, edge0);
 471         VectorSubtract(brush->points[0].v, brush->points[1].v, edge1);
 472         VectorSubtract(brush->points[1].v, brush->points[2].v, edge2);
 473         VectorCopy(edge0, brush->edgedirs[0].v);
 474         VectorCopy(edge1, brush->edgedirs[1].v);
 475         VectorCopy(edge2, brush->edgedirs[2].v);
 476         // now select an algorithm to generate the side planes
 477         if (collision_triangle_bevelsides.integer)
 478         {
 479                 // use 45 degree slopes at the edges of the triangle to make a sinking trace error turn into "riding up" the slope rather than getting stuck
 480                 CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 481                 CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 482                 CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 483                 VectorNormalize(brush->planes[2].normal);
 484                 VectorNormalize(brush->planes[3].normal);
 485                 VectorNormalize(brush->planes[4].normal);
 486                 VectorAdd(brush->planes[2].normal, brush->planes[0].normal, brush->planes[2].normal);
 487                 VectorAdd(brush->planes[3].normal, brush->planes[0].normal, brush->planes[3].normal);
 488                 VectorAdd(brush->planes[4].normal, brush->planes[0].normal, brush->planes[4].normal);
 489                 VectorNormalize(brush->planes[2].normal);
 490                 VectorNormalize(brush->planes[3].normal);
 491                 VectorNormalize(brush->planes[4].normal);
 492         }
 493         else if (collision_triangle_axialsides.integer)
 494         {
 495                 float projectionnormal[3], projectionedge0[3], projectionedge1[3], projectionedge2[3];
 496                 int i, best;
 497                 float dist, bestdist;
 498                 bestdist = fabs(brush->planes[0].normal[0]);
 499                 best = 0;
 500                 for (i = 1;i < 3;i++)
 501                 {
 502                         dist = fabs(brush->planes[0].normal[i]);
 503                         if (bestdist < dist)
 504                         {
 505                                 bestdist = dist;
 506                                 best = i;
 507                         }
 508                 }
 509                 VectorClear(projectionnormal);
 510                 if (brush->planes[0].normal[best] < 0)
 511                         projectionnormal[best] = -1;
 512                 else
 513                         projectionnormal[best] = 1;
 514                 VectorCopy(edge0, projectionedge0);
 515                 VectorCopy(edge1, projectionedge1);
 516                 VectorCopy(edge2, projectionedge2);
 517                 projectionedge0[best] = 0;
 518                 projectionedge1[best] = 0;
 519                 projectionedge2[best] = 0;
 520                 CrossProduct(projectionedge0, projectionnormal, brush->planes[2].normal);
 521                 CrossProduct(projectionedge1, projectionnormal, brush->planes[3].normal);
 522                 CrossProduct(projectionedge2, projectionnormal, brush->planes[4].normal);
 523                 VectorNormalize(brush->planes[2].normal);
 524                 VectorNormalize(brush->planes[3].normal);
 525                 VectorNormalize(brush->planes[4].normal);
 526         }
 527         else
 528         {
 529                 CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 530                 CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 531                 CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 532                 VectorNormalize(brush->planes[2].normal);
 533                 VectorNormalize(brush->planes[3].normal);
 534                 VectorNormalize(brush->planes[4].normal);
 535         }
 536         brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
 537         brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
 538         brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
 539
 540         if (developer_extra.integer)
 541         {
 542                 // validity check - will be disabled later
 543                 Collision_ValidateBrush(brush);
 544                 for (i = 0;i < brush->numplanes;i++)
 545                 {
 546                         int j;
 547                         for (j = 0, p = brush->points;j < brush->numpoints;j++, p++)
 548                                 if (DotProduct(p->v, brush->planes[i].normal) > brush->planes[i].dist + COLLISION_PLANE_DIST_EPSILON)
 549                                         Con_DPrintf("Error in brush plane generation, plane %i\n", i);
 550                 }
 551         }
 552 }
 553
 554 colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents, int q3surfaceflags, const texture_t *texture)
 555 {
 556         colbrushf_t *brush;
 557         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2) + sizeof(colpointf_t) * numpoints);
 558         brush->isaabb = false;
 559         brush->hasaabbplanes = false;
 560         brush->supercontents = supercontents;
 561         brush->numpoints = numpoints;
 562         brush->numedgedirs = numpoints;
 563         brush->numplanes = numpoints + 2;
 564         brush->planes = (colplanef_t *)(brush + 1);
 565         brush->points = (colpointf_t *)points;
 566         brush->edgedirs = (colpointf_t *)(brush->planes + brush->numplanes);
 567         brush->q3surfaceflags = q3surfaceflags;
 568         brush->texture = texture;
 569         Sys_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...");
 570         return brush;
 571 }
 572
 573 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 574 void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *trace_start, const colbrushf_t *trace_end, const colbrushf_t *other_start, const colbrushf_t *other_end)
 575 {
 576         int nplane, nplane2, nedge1, nedge2, hitq3surfaceflags = 0;
 577         int tracenumedgedirs = trace_start->numedgedirs;
 578         //int othernumedgedirs = other_start->numedgedirs;
 579         int tracenumpoints = trace_start->numpoints;
 580         int othernumpoints = other_start->numpoints;
 581         int numplanes1 = other_start->numplanes;
 582         int numplanes2 = numplanes1 + trace_start->numplanes;
 583         int numplanes3 = numplanes2 + trace_start->numedgedirs * other_start->numedgedirs * 2;
 584         vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
 585         vec4_t startplane;
 586         vec4_t endplane;
 587         vec4_t newimpactplane;
 588         const texture_t *hittexture = NULL;
 589         vec_t startdepth = 1;
 590         vec3_t startdepthnormal;
 591
 592         VectorClear(startdepthnormal);
 593         Vector4Clear(newimpactplane);
 594
 595         // fast case for AABB vs compiled brushes (which begin with AABB planes and also have precomputed bevels for AABB collisions)
 596         if (trace_start->isaabb && other_start->hasaabbplanes)
 597                 numplanes3 = numplanes2 = numplanes1;
 598
 599         // Separating Axis Theorem:
 600         // if a supporting vector (plane normal) can be found that separates two
 601         // objects, they are not colliding.
 602         //
 603         // Minkowski Sum:
 604         // reduce the size of one object to a point while enlarging the other to
 605         // represent the space that point can not occupy.
 606         //
 607         // try every plane we can construct between the two brushes and measure
 608         // the distance between them.
 609         for (nplane = 0;nplane < numplanes3;nplane++)
 610         {
 611                 if (nplane < numplanes1)
 612                 {
 613                         nplane2 = nplane;
 614                         VectorCopy(other_start->planes[nplane2].normal, startplane);
 615                         VectorCopy(other_end->planes[nplane2].normal, endplane);
 616                 }
 617                 else if (nplane < numplanes2)
 618                 {
 619                         nplane2 = nplane - numplanes1;
 620                         VectorCopy(trace_start->planes[nplane2].normal, startplane);
 621                         VectorCopy(trace_end->planes[nplane2].normal, endplane);
 622                 }
 623                 else
 624                 {
 625                         // pick an edgedir from each brush and cross them
 626                         nplane2 = nplane - numplanes2;
 627                         nedge1 = nplane2 >> 1;
 628                         nedge2 = nedge1 / tracenumedgedirs;
 629                         nedge1 -= nedge2 * tracenumedgedirs;
 630                         if (nplane2 & 1)
 631                         {
 632                                 CrossProduct(trace_start->edgedirs[nedge1].v, other_start->edgedirs[nedge2].v, startplane);
 633                                 CrossProduct(trace_end->edgedirs[nedge1].v, other_end->edgedirs[nedge2].v, endplane);
 634                         }
 635                         else
 636                         {
 637                                 CrossProduct(other_start->edgedirs[nedge2].v, trace_start->edgedirs[nedge1].v, startplane);
 638                                 CrossProduct(other_end->edgedirs[nedge2].v, trace_end->edgedirs[nedge1].v, endplane);
 639                         }
 640                         if (VectorLength2(startplane) < COLLISION_EDGECROSS_MINLENGTH2 || VectorLength2(endplane) < COLLISION_EDGECROSS_MINLENGTH2)
 641                                 continue; // degenerate crossproducts
 642                         VectorNormalize(startplane);
 643                         VectorNormalize(endplane);
 644                 }
 645                 startplane[3] = furthestplanedist_float(startplane, other_start->points, othernumpoints);
 646                 endplane[3] = furthestplanedist_float(startplane, other_end->points, othernumpoints);
 647                 startdist = nearestplanedist_float(startplane, trace_start->points, tracenumpoints) - startplane[3];
 648                 enddist = nearestplanedist_float(endplane, trace_end->points, tracenumpoints) - endplane[3];
 649                 //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
 650
 651                 // aside from collisions, this is also used for error correction
 652                 if (startdist <= collision_impactnudge.value && nplane < numplanes1 && (startdepth < startdist || startdepth == 1))
 653                 {
 654                         startdepth = startdist;
 655                         VectorCopy(startplane, startdepthnormal);
 656                 }
 657
 658                 if (startdist > enddist)
 659                 {
 660                         // moving into brush
 661                         if (enddist > 0.0f)
 662                                 return;
 663                         if (startdist >= 0)
 664                         {
 665                                 // enter
 666                                 imove = 1 / (startdist - enddist);
 667                                 f = startdist * imove;
 668                                 // check if this will reduce the collision time range
 669                                 if (enterfrac < f)
 670                                 {
 671                                         // reduced collision time range
 672                                         enterfrac = f;
 673                                         // if the collision time range is now empty, no collision
 674                                         if (enterfrac > leavefrac)
 675                                                 return;
 676                                         // calculate the nudged fraction and impact normal we'll
 677                                         // need if we accept this collision later
 678                                         enterfrac2 = (startdist - collision_impactnudge.value) * imove;
 679                                         // if the collision would be further away than the trace's
 680                                         // existing collision data, we don't care about this
 681                                         // collision
 682                                         if (enterfrac2 >= trace->fraction)
 683                                                 return;
 684                                         ie = 1.0f - enterfrac;
 685                                         newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
 686                                         newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
 687                                         newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
 688                                         newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
 689                                         if (nplane < numplanes1)
 690                                         {
 691                                                 // use the plane from other
 692                                                 nplane2 = nplane;
 693                                                 hitq3surfaceflags = other_start->planes[nplane2].q3surfaceflags;
 694                                                 hittexture = other_start->planes[nplane2].texture;
 695                                         }
 696                                         else if (nplane < numplanes2)
 697                                         {
 698                                                 // use the plane from trace
 699                                                 nplane2 = nplane - numplanes1;
 700                                                 hitq3surfaceflags = trace_start->planes[nplane2].q3surfaceflags;
 701                                                 hittexture = trace_start->planes[nplane2].texture;
 702                                         }
 703                                         else
 704                                         {
 705                                                 hitq3surfaceflags = other_start->q3surfaceflags;
 706                                                 hittexture = other_start->texture;
 707                                         }
 708                                 }
 709                         }
 710                 }
 711                 else
 712                 {
 713                         // moving out of brush
 714                         if (startdist >= 0)
 715                                 return;
 716                         if (enddist > 0)
 717                         {
 718                                 // leave
 719                                 f = startdist / (startdist - enddist);
 720                                 // check if this will reduce the collision time range
 721                                 if (leavefrac > f)
 722                                 {
 723                                         // reduced collision time range
 724                                         leavefrac = f;
 725                                         // if the collision time range is now empty, no collision
 726                                         if (enterfrac > leavefrac)
 727                                                 return;
 728                                 }
 729                         }
 730                 }
 731         }
 732
 733         // at this point we know the trace overlaps the brush because it was not
 734         // rejected at any point in the loop above
 735
 736         // see if the trace started outside the brush or not
 737         if (enterfrac > -1)
 738         {
 739                 // started outside, and overlaps, therefore there is a collision here
 740                 // store out the impact information
 741                 if (trace->hitsupercontentsmask & other_start->supercontents)
 742                 {
 743                         trace->hitsupercontents = other_start->supercontents;
 744                         trace->hitq3surfaceflags = hitq3surfaceflags;
 745                         trace->hittexture = hittexture;
 746                         trace->fraction = bound(0, enterfrac2, 1);
 747                         VectorCopy(newimpactplane, trace->plane.normal);
 748                         trace->plane.dist = newimpactplane[3];
 749                 }
 750         }
 751         else
 752         {
 753                 // started inside, update startsolid and friends
 754                 trace->startsupercontents |= other_start->supercontents;
 755                 if (trace->hitsupercontentsmask & other_start->supercontents)
 756                 {
 757                         trace->startsolid = true;
 758                         if (leavefrac < 1)
 759                                 trace->allsolid = true;
 760                         VectorCopy(newimpactplane, trace->plane.normal);
 761                         trace->plane.dist = newimpactplane[3];
 762                         if (trace->startdepth > startdepth)
 763                         {
 764                                 trace->startdepth = startdepth;
 765                                 VectorCopy(startdepthnormal, trace->startdepthnormal);
 766                         }
 767                 }
 768         }
 769 }
 770
 771 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 772 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *other_start, const colbrushf_t *other_end)
 773 {
 774         int nplane, hitq3surfaceflags = 0;
 775         int numplanes = other_start->numplanes;
 776         vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
 777         vec4_t startplane;
 778         vec4_t endplane;
 779         vec4_t newimpactplane;
 780         const texture_t *hittexture = NULL;
 781         vec_t startdepth = 1;
 782         vec3_t startdepthnormal;
 783
 784         if (collision_debug_tracelineasbox.integer)
 785         {
 786                 colboxbrushf_t thisbrush_start, thisbrush_end;
 787                 Collision_BrushForBox(&thisbrush_start, linestart, linestart, 0, 0, NULL);
 788                 Collision_BrushForBox(&thisbrush_end, lineend, lineend, 0, 0, NULL);
 789                 Collision_TraceBrushBrushFloat(trace, &thisbrush_start.brush, &thisbrush_end.brush, other_start, other_end);
 790                 return;
 791         }
 792
 793         VectorClear(startdepthnormal);
 794         Vector4Clear(newimpactplane);
 795
 796         // Separating Axis Theorem:
 797         // if a supporting vector (plane normal) can be found that separates two
 798         // objects, they are not colliding.
 799         //
 800         // Minkowski Sum:
 801         // reduce the size of one object to a point while enlarging the other to
 802         // represent the space that point can not occupy.
 803         //
 804         // try every plane we can construct between the two brushes and measure
 805         // the distance between them.
 806         for (nplane = 0;nplane < numplanes;nplane++)
 807         {
 808                 VectorCopy(other_start->planes[nplane].normal, startplane);
 809                 startplane[3] = other_start->planes[nplane].dist;
 810                 VectorCopy(other_end->planes[nplane].normal, endplane);
 811                 endplane[3] = other_end->planes[nplane].dist;
 812                 startdist = DotProduct(linestart, startplane) - startplane[3];
 813                 enddist = DotProduct(lineend, endplane) - endplane[3];
 814                 //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
 815
 816                 // aside from collisions, this is also used for error correction
 817                 if (startdist < collision_impactnudge.value && (startdepth < startdist || startdepth == 1))
 818                 {
 819                         startdepth = startdist;
 820                         VectorCopy(startplane, startdepthnormal);
 821                 }
 822
 823                 if (startdist > enddist)
 824                 {
 825                         // moving into brush
 826                         if (enddist > 0.0f)
 827                                 return;
 828                         if (startdist > 0)
 829                         {
 830                                 // enter
 831                                 imove = 1 / (startdist - enddist);
 832                                 f = startdist * imove;
 833                                 // check if this will reduce the collision time range
 834                                 if (enterfrac < f)
 835                                 {
 836                                         // reduced collision time range
 837                                         enterfrac = f;
 838                                         // if the collision time range is now empty, no collision
 839                                         if (enterfrac > leavefrac)
 840                                                 return;
 841                                         // calculate the nudged fraction and impact normal we'll
 842                                         // need if we accept this collision later
 843                                         enterfrac2 = (startdist - collision_impactnudge.value) * imove;
 844                                         // if the collision would be further away than the trace's
 845                                         // existing collision data, we don't care about this
 846                                         // collision
 847                                         if (enterfrac2 >= trace->fraction)
 848                                                 return;
 849                                         ie = 1.0f - enterfrac;
 850                                         newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
 851                                         newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
 852                                         newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
 853                                         newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
 854                                         hitq3surfaceflags = other_start->planes[nplane].q3surfaceflags;
 855                                         hittexture = other_start->planes[nplane].texture;
 856                                 }
 857                         }
 858                 }
 859                 else
 860                 {
 861                         // moving out of brush
 862                         if (startdist > 0)
 863                                 return;
 864                         if (enddist > 0)
 865                         {
 866                                 // leave
 867                                 f = startdist / (startdist - enddist);
 868                                 // check if this will reduce the collision time range
 869                                 if (leavefrac > f)
 870                                 {
 871                                         // reduced collision time range
 872                                         leavefrac = f;
 873                                         // if the collision time range is now empty, no collision
 874                                         if (enterfrac > leavefrac)
 875                                                 return;
 876                                 }
 877                         }
 878                 }
 879         }
 880
 881         // at this point we know the trace overlaps the brush because it was not
 882         // rejected at any point in the loop above
 883
 884         // see if the trace started outside the brush or not
 885         if (enterfrac > -1)
 886         {
 887                 // started outside, and overlaps, therefore there is a collision here
 888                 // store out the impact information
 889                 if (trace->hitsupercontentsmask & other_start->supercontents)
 890                 {
 891                         trace->hitsupercontents = other_start->supercontents;
 892                         trace->hitq3surfaceflags = hitq3surfaceflags;
 893                         trace->hittexture = hittexture;
 894                         trace->fraction = bound(0, enterfrac2, 1);
 895                         VectorCopy(newimpactplane, trace->plane.normal);
 896                         trace->plane.dist = newimpactplane[3];
 897                 }
 898         }
 899         else
 900         {
 901                 // started inside, update startsolid and friends
 902                 trace->startsupercontents |= other_start->supercontents;
 903                 if (trace->hitsupercontentsmask & other_start->supercontents)
 904                 {
 905                         trace->startsolid = true;
 906                         if (leavefrac < 1)
 907                                 trace->allsolid = true;
 908                         VectorCopy(newimpactplane, trace->plane.normal);
 909                         trace->plane.dist = newimpactplane[3];
 910                         if (trace->startdepth > startdepth)
 911                         {
 912                                 trace->startdepth = startdepth;
 913                                 VectorCopy(startdepthnormal, trace->startdepthnormal);
 914                         }
 915                 }
 916         }
 917 }
 918
 919 qboolean Collision_PointInsideBrushFloat(const vec3_t point, const colbrushf_t *brush)
 920 {
 921         int nplane;
 922         const colplanef_t *plane;
 923
 924         if (!BoxesOverlap(point, point, brush->mins, brush->maxs))
 925                 return false;
 926         for (nplane = 0, plane = brush->planes;nplane < brush->numplanes;nplane++, plane++)
 927                 if (DotProduct(plane->normal, point) > plane->dist)
 928                         return false;
 929         return true;
 930 }
 931
 932 void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
 933 {
 934         if (!Collision_PointInsideBrushFloat(point, thatbrush))
 935                 return;
 936
 937         trace->startsupercontents |= thatbrush->supercontents;
 938         if (trace->hitsupercontentsmask & thatbrush->supercontents)
 939         {
 940                 trace->startsolid = true;
 941                 trace->allsolid = true;
 942         }
 943 }
 944
 945 static void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
 946 {
 947         int i;
 948         for (i = 0;i < numpoints;i++)
 949         {
 950                 out[i].v[0] = floor(in[i].v[0] * fractionprecision + 0.5f) * invfractionprecision;
 951                 out[i].v[1] = floor(in[i].v[1] * fractionprecision + 0.5f) * invfractionprecision;
 952                 out[i].v[2] = floor(in[i].v[2] * fractionprecision + 0.5f) * invfractionprecision;
 953         }
 954 }
 955
 956 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 stride, float *bbox6f, int supercontents, int q3surfaceflags, const texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 957 {
 958         int i;
 959         colpointf_t points[3];
 960         colpointf_t edgedirs[3];
 961         colplanef_t planes[5];
 962         colbrushf_t brush;
 963         memset(&brush, 0, sizeof(brush));
 964         brush.isaabb = false;
 965         brush.hasaabbplanes = false;
 966         brush.numpoints = 3;
 967         brush.numedgedirs = 3;
 968         brush.numplanes = 5;
 969         brush.points = points;
 970         brush.edgedirs = edgedirs;
 971         brush.planes = planes;
 972         brush.supercontents = supercontents;
 973         brush.q3surfaceflags = q3surfaceflags;
 974         brush.texture = texture;
 975         for (i = 0;i < brush.numplanes;i++)
 976         {
 977                 brush.planes[i].q3surfaceflags = q3surfaceflags;
 978                 brush.planes[i].texture = texture;
 979         }
 980         if(stride > 0)
 981         {
 982                 int k, cnt, tri;
 983                 cnt = (numtriangles + stride - 1) / stride;
 984                 for(i = 0; i < cnt; ++i)
 985                 {
 986                         if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
 987                         {
 988                                 for(k = 0; k < stride; ++k)
 989                                 {
 990                                         tri = i * stride + k;
 991                                         if(tri >= numtriangles)
 992                                                 break;
 993                                         VectorCopy(vertex3f + element3i[tri * 3 + 0] * 3, points[0].v);
 994                                         VectorCopy(vertex3f + element3i[tri * 3 + 1] * 3, points[1].v);
 995                                         VectorCopy(vertex3f + element3i[tri * 3 + 2] * 3, points[2].v);
 996                                         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
 997                                         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
 998                                         Collision_CalcPlanesForTriangleBrushFloat(&brush);
 999                                         //Collision_PrintBrushAsQHull(&brush, "brush");
1000                                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1001                                 }
1002                         }
1003                 }
1004         }
1005         else if(stride == 0)
1006         {
1007                 for (i = 0;i < numtriangles;i++, element3i += 3)
1008                 {
1009                         if (TriangleBBoxOverlapsBox(vertex3f + element3i[0]*3, vertex3f + element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
1010                         {
1011                                 VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
1012                                 VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
1013                                 VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
1014                                 Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1015                                 Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1016                                 Collision_CalcPlanesForTriangleBrushFloat(&brush);
1017                                 //Collision_PrintBrushAsQHull(&brush, "brush");
1018                                 Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1019                         }
1020                 }
1021         }
1022         else
1023         {
1024                 for (i = 0;i < numtriangles;i++, element3i += 3)
1025                 {
1026                         VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
1027                         VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
1028                         VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
1029                         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1030                         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1031                         Collision_CalcPlanesForTriangleBrushFloat(&brush);
1032                         //Collision_PrintBrushAsQHull(&brush, "brush");
1033                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1034                 }
1035         }
1036 }
1037
1038 void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numtriangles, const int *element3i, const float *vertex3f, int stride, float *bbox6f, int supercontents, int q3surfaceflags, const texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
1039 {
1040         int i;
1041         // FIXME: snap vertices?
1042         if(stride > 0)
1043         {
1044                 int k, cnt, tri;
1045                 cnt = (numtriangles + stride - 1) / stride;
1046                 for(i = 0; i < cnt; ++i)
1047                 {
1048                         if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
1049                         {
1050                                 for(k = 0; k < stride; ++k)
1051                                 {
1052                                         tri = i * stride + k;
1053                                         if(tri >= numtriangles)
1054                                                 break;
1055                                         Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[tri * 3 + 0] * 3, vertex3f + element3i[tri * 3 + 1] * 3, vertex3f + element3i[tri * 3 + 2] * 3, supercontents, q3surfaceflags, texture);
1056                                 }
1057                         }
1058                 }
1059         }
1060         else
1061         {
1062                 for (i = 0;i < numtriangles;i++, element3i += 3)
1063                         Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3, supercontents, q3surfaceflags, texture);
1064         }
1065 }
1066
1067 void Collision_TraceBrushTriangleFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, const float *v0, const float *v1, const float *v2, int supercontents, int q3surfaceflags, const texture_t *texture)
1068 {
1069         int i;
1070         colpointf_t points[3];
1071         colpointf_t edgedirs[3];
1072         colplanef_t planes[5];
1073         colbrushf_t brush;
1074         memset(&brush, 0, sizeof(brush));
1075         brush.isaabb = false;
1076         brush.hasaabbplanes = false;
1077         brush.numpoints = 3;
1078         brush.numedgedirs = 3;
1079         brush.numplanes = 5;
1080         brush.points = points;
1081         brush.edgedirs = edgedirs;
1082         brush.planes = planes;
1083         brush.supercontents = supercontents;
1084         brush.q3surfaceflags = q3surfaceflags;
1085         brush.texture = texture;
1086         for (i = 0;i < brush.numplanes;i++)
1087         {
1088                 brush.planes[i].q3surfaceflags = q3surfaceflags;
1089                 brush.planes[i].texture = texture;
1090         }
1091         VectorCopy(v0, points[0].v);
1092         VectorCopy(v1, points[1].v);
1093         VectorCopy(v2, points[2].v);
1094         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1095         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1096         Collision_CalcPlanesForTriangleBrushFloat(&brush);
1097         //Collision_PrintBrushAsQHull(&brush, "brush");
1098         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1099 }
1100
1101 void Collision_BrushForBox(colboxbrushf_t *boxbrush, const vec3_t mins, const vec3_t maxs, int supercontents, int q3surfaceflags, const texture_t *texture)
1102 {
1103         int i;
1104         memset(boxbrush, 0, sizeof(*boxbrush));
1105         boxbrush->brush.isaabb = true;
1106         boxbrush->brush.hasaabbplanes = true;
1107         boxbrush->brush.points = boxbrush->points;
1108         boxbrush->brush.edgedirs = boxbrush->edgedirs;
1109         boxbrush->brush.planes = boxbrush->planes;
1110         boxbrush->brush.supercontents = supercontents;
1111         boxbrush->brush.q3surfaceflags = q3surfaceflags;
1112         boxbrush->brush.texture = texture;
1113         if (VectorCompare(mins, maxs))
1114         {
1115                 // point brush
1116                 boxbrush->brush.numpoints = 1;
1117                 boxbrush->brush.numedgedirs = 0;
1118                 boxbrush->brush.numplanes = 0;
1119                 VectorCopy(mins, boxbrush->brush.points[0].v);
1120         }
1121         else
1122         {
1123                 boxbrush->brush.numpoints = 8;
1124                 boxbrush->brush.numedgedirs = 3;
1125                 boxbrush->brush.numplanes = 6;
1126                 // there are 8 points on a box
1127                 // there are 3 edgedirs on a box (both signs are tested in collision)
1128                 // there are 6 planes on a box
1129                 VectorSet(boxbrush->brush.points[0].v, mins[0], mins[1], mins[2]);
1130                 VectorSet(boxbrush->brush.points[1].v, maxs[0], mins[1], mins[2]);
1131                 VectorSet(boxbrush->brush.points[2].v, mins[0], maxs[1], mins[2]);
1132                 VectorSet(boxbrush->brush.points[3].v, maxs[0], maxs[1], mins[2]);
1133                 VectorSet(boxbrush->brush.points[4].v, mins[0], mins[1], maxs[2]);
1134                 VectorSet(boxbrush->brush.points[5].v, maxs[0], mins[1], maxs[2]);
1135                 VectorSet(boxbrush->brush.points[6].v, mins[0], maxs[1], maxs[2]);
1136                 VectorSet(boxbrush->brush.points[7].v, maxs[0], maxs[1], maxs[2]);
1137                 VectorSet(boxbrush->brush.edgedirs[0].v, 1, 0, 0);
1138                 VectorSet(boxbrush->brush.edgedirs[1].v, 0, 1, 0);
1139                 VectorSet(boxbrush->brush.edgedirs[2].v, 0, 0, 1);
1140                 VectorSet(boxbrush->brush.planes[0].normal, -1,  0,  0);boxbrush->brush.planes[0].dist = -mins[0];
1141                 VectorSet(boxbrush->brush.planes[1].normal,  1,  0,  0);boxbrush->brush.planes[1].dist =  maxs[0];
1142                 VectorSet(boxbrush->brush.planes[2].normal,  0, -1,  0);boxbrush->brush.planes[2].dist = -mins[1];
1143                 VectorSet(boxbrush->brush.planes[3].normal,  0,  1,  0);boxbrush->brush.planes[3].dist =  maxs[1];
1144                 VectorSet(boxbrush->brush.planes[4].normal,  0,  0, -1);boxbrush->brush.planes[4].dist = -mins[2];
1145                 VectorSet(boxbrush->brush.planes[5].normal,  0,  0,  1);boxbrush->brush.planes[5].dist =  maxs[2];
1146                 for (i = 0;i < 6;i++)
1147                 {
1148                         boxbrush->brush.planes[i].q3surfaceflags = q3surfaceflags;
1149                         boxbrush->brush.planes[i].texture = texture;
1150                 }
1151         }
1152         boxbrush->brush.supercontents = supercontents;
1153         boxbrush->brush.q3surfaceflags = q3surfaceflags;
1154         boxbrush->brush.texture = texture;
1155         VectorSet(boxbrush->brush.mins, mins[0] - 1, mins[1] - 1, mins[2] - 1);
1156         VectorSet(boxbrush->brush.maxs, maxs[0] + 1, maxs[1] + 1, maxs[2] + 1);
1157         //Collision_ValidateBrush(&boxbrush->brush);
1158 }
1159
1160 //pseudocode for detecting line/sphere overlap without calculating an impact point
1161 //linesphereorigin = sphereorigin - linestart;linediff = lineend - linestart;linespherefrac = DotProduct(linesphereorigin, linediff) / DotProduct(linediff, linediff);return VectorLength2(linesphereorigin - bound(0, linespherefrac, 1) * linediff) >= sphereradius*sphereradius;
1162
1163 // LordHavoc: currently unused, but tested
1164 // note: this can be used for tracing a moving sphere vs a stationary sphere,
1165 // by simply adding the moving sphere's radius to the sphereradius parameter,
1166 // all the results are correct (impactpoint, impactnormal, and fraction)
1167 float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double *sphereorigin, double sphereradius, double *impactpoint, double *impactnormal)
1168 {
1169         double dir[3], scale, v[3], deviationdist2, impactdist, linelength;
1170         // make sure the impactpoint and impactnormal are valid even if there is
1171         // no collision
1172         VectorCopy(lineend, impactpoint);
1173         VectorClear(impactnormal);
1174         // calculate line direction
1175         VectorSubtract(lineend, linestart, dir);
1176         // normalize direction
1177         linelength = VectorLength(dir);
1178         if (linelength)
1179         {
1180                 scale = 1.0 / linelength;
1181                 VectorScale(dir, scale, dir);
1182         }
1183         // this dotproduct calculates the distance along the line at which the
1184         // sphere origin is (nearest point to the sphere origin on the line)
1185         impactdist = DotProduct(sphereorigin, dir) - DotProduct(linestart, dir);
1186         // calculate point on line at that distance, and subtract the
1187         // sphereorigin from it, so we have a vector to measure for the distance
1188         // of the line from the sphereorigin (deviation, how off-center it is)
1189         VectorMA(linestart, impactdist, dir, v);
1190         VectorSubtract(v, sphereorigin, v);
1191         deviationdist2 = sphereradius * sphereradius - VectorLength2(v);
1192         // if squared offset length is outside the squared sphere radius, miss
1193         if (deviationdist2 < 0)
1194                 return 1; // miss (off to the side)
1195         // nudge back to find the correct impact distance
1196         impactdist -= sqrt(deviationdist2);
1197         if (impactdist >= linelength)
1198                 return 1; // miss (not close enough)
1199         if (impactdist < 0)
1200                 return 1; // miss (linestart is past or inside sphere)
1201         // calculate new impactpoint
1202         VectorMA(linestart, impactdist, dir, impactpoint);
1203         // calculate impactnormal (surface normal at point of impact)
1204         VectorSubtract(impactpoint, sphereorigin, impactnormal);
1205         // normalize impactnormal
1206         VectorNormalize(impactnormal);
1207         // return fraction of movement distance
1208         return impactdist / linelength;
1209 }
1210
1211 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, const texture_t *texture)
1212 {
1213         float d1, d2, d, f, f2, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
1214
1215         // this function executes:
1216         // 32 ops when line starts behind triangle
1217         // 38 ops when line ends infront of triangle
1218         // 43 ops when line fraction is already closer than this triangle
1219         // 72 ops when line is outside edge 01
1220         // 92 ops when line is outside edge 21
1221         // 115 ops when line is outside edge 02
1222         // 123 ops when line impacts triangle and updates trace results
1223
1224         // this code is designed for clockwise triangles, conversion to
1225         // counterclockwise would require swapping some things around...
1226         // it is easier to simply swap the point0 and point2 parameters to this
1227         // function when calling it than it is to rewire the internals.
1228
1229         // calculate the faceplanenormal of the triangle, this represents the front side
1230         // 15 ops
1231         VectorSubtract(point0, point1, edge01);
1232         VectorSubtract(point2, point1, edge21);
1233         CrossProduct(edge01, edge21, faceplanenormal);
1234         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
1235         // 6 ops
1236         faceplanenormallength2 = DotProduct(faceplanenormal, faceplanenormal);
1237         if (faceplanenormallength2 < 0.0001f)
1238                 return;
1239         // calculate the distance
1240         // 5 ops
1241         faceplanedist = DotProduct(point0, faceplanenormal);
1242
1243         // if start point is on the back side there is no collision
1244         // (we don't care about traces going through the triangle the wrong way)
1245
1246         // calculate the start distance
1247         // 6 ops
1248         d1 = DotProduct(faceplanenormal, linestart);
1249         if (d1 <= faceplanedist)
1250                 return;
1251
1252         // calculate the end distance
1253         // 6 ops
1254         d2 = DotProduct(faceplanenormal, lineend);
1255         // if both are in front, there is no collision
1256         if (d2 >= faceplanedist)
1257                 return;
1258
1259         // from here on we know d1 is >= 0 and d2 is < 0
1260         // this means the line starts infront and ends behind, passing through it
1261
1262         // calculate the recipricol of the distance delta,
1263         // so we can use it multiple times cheaply (instead of division)
1264         // 2 ops
1265         d = 1.0f / (d1 - d2);
1266         // calculate the impact fraction by taking the start distance (> 0)
1267         // and subtracting the face plane distance (this is the distance of the
1268         // triangle along that same normal)
1269         // then multiply by the recipricol distance delta
1270         // 4 ops
1271         f = (d1 - faceplanedist) * d;
1272         f2  = f - collision_impactnudge.value * d;
1273         // skip out if this impact is further away than previous ones
1274         // 1 ops
1275         if (f2 >= trace->fraction)
1276                 return;
1277         // calculate the perfect impact point for classification of insidedness
1278         // 9 ops
1279         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1280         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1281         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1282
1283         // calculate the edge normal and reject if impact is outside triangle
1284         // (an edge normal faces away from the triangle, to get the desired normal
1285         //  a crossproduct with the faceplanenormal is used, and because of the way
1286         // the insidedness comparison is written it does not need to be normalized)
1287
1288         // first use the two edges from the triangle plane math
1289         // the other edge only gets calculated if the point survives that long
1290
1291         // 20 ops
1292         CrossProduct(edge01, faceplanenormal, edgenormal);
1293         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1294                 return;
1295
1296         // 20 ops
1297         CrossProduct(faceplanenormal, edge21, edgenormal);
1298         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1299                 return;
1300
1301         // 23 ops
1302         VectorSubtract(point0, point2, edge02);
1303         CrossProduct(faceplanenormal, edge02, edgenormal);
1304         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1305                 return;
1306
1307         // 8 ops (rare)
1308
1309         // store the new trace fraction
1310         trace->fraction = f2;
1311
1312         // store the new trace plane (because collisions only happen from
1313         // the front this is always simply the triangle normal, never flipped)
1314         d = 1.0 / sqrt(faceplanenormallength2);
1315         VectorScale(faceplanenormal, d, trace->plane.normal);
1316         trace->plane.dist = faceplanedist * d;
1317
1318         trace->hitsupercontents = supercontents;
1319         trace->hitq3surfaceflags = q3surfaceflags;
1320         trace->hittexture = texture;
1321 }
1322
1323 void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const colbrushf_t *end, vec3_t mins, vec3_t maxs, float startfrac, float endfrac)
1324 {
1325         int i;
1326         colpointf_t *ps, *pe;
1327         float tempstart[3], tempend[3];
1328         VectorLerp(start->points[0].v, startfrac, end->points[0].v, mins);
1329         VectorCopy(mins, maxs);
1330         for (i = 0, ps = start->points, pe = end->points;i < start->numpoints;i++, ps++, pe++)
1331         {
1332                 VectorLerp(ps->v, startfrac, pe->v, tempstart);
1333                 VectorLerp(ps->v, endfrac, pe->v, tempend);
1334                 mins[0] = min(mins[0], min(tempstart[0], tempend[0]));
1335                 mins[1] = min(mins[1], min(tempstart[1], tempend[1]));
1336                 mins[2] = min(mins[2], min(tempstart[2], tempend[2]));
1337                 maxs[0] = min(maxs[0], min(tempstart[0], tempend[0]));
1338                 maxs[1] = min(maxs[1], min(tempstart[1], tempend[1]));
1339                 maxs[2] = min(maxs[2], min(tempstart[2], tempend[2]));
1340         }
1341         mins[0] -= 1;
1342         mins[1] -= 1;
1343         mins[2] -= 1;
1344         maxs[0] += 1;
1345         maxs[1] += 1;
1346         maxs[2] += 1;
1347 }
1348
1349 //===========================================
1350
1351 static void Collision_TranslateBrush(const vec3_t shift, colbrushf_t *brush)
1352 {
1353         int i;
1354         // now we can transform the data
1355         for(i = 0; i < brush->numplanes; ++i)
1356         {
1357                 brush->planes[i].dist += DotProduct(shift, brush->planes[i].normal);
1358         }
1359         for(i = 0; i < brush->numpoints; ++i)
1360         {
1361                 VectorAdd(brush->points[i].v, shift, brush->points[i].v);
1362         }
1363         VectorAdd(brush->mins, shift, brush->mins);
1364         VectorAdd(brush->maxs, shift, brush->maxs);
1365 }
1366
1367 static void Collision_TransformBrush(const matrix4x4_t *matrix, colbrushf_t *brush)
1368 {
1369         int i;
1370         vec3_t v;
1371         // we're breaking any AABB properties here...
1372         brush->isaabb = false;
1373         brush->hasaabbplanes = false;
1374         // now we can transform the data
1375         for(i = 0; i < brush->numplanes; ++i)
1376         {
1377                 Matrix4x4_TransformPositivePlane(matrix, brush->planes[i].normal[0], brush->planes[i].normal[1], brush->planes[i].normal[2], brush->planes[i].dist, brush->planes[i].normal);
1378         }
1379         for(i = 0; i < brush->numedgedirs; ++i)
1380         {
1381                 Matrix4x4_Transform(matrix, brush->edgedirs[i].v, v);
1382                 VectorCopy(v, brush->edgedirs[i].v);
1383         }
1384         for(i = 0; i < brush->numpoints; ++i)
1385         {
1386                 Matrix4x4_Transform(matrix, brush->points[i].v, v);
1387                 VectorCopy(v, brush->points[i].v);
1388         }
1389         VectorCopy(brush->points[0].v, brush->mins);
1390         VectorCopy(brush->points[0].v, brush->maxs);
1391         for(i = 1; i < brush->numpoints; ++i)
1392         {
1393                 if(brush->points[i].v[0] < brush->mins[0]) brush->mins[0] = brush->points[i].v[0];
1394                 if(brush->points[i].v[1] < brush->mins[1]) brush->mins[1] = brush->points[i].v[1];
1395                 if(brush->points[i].v[2] < brush->mins[2]) brush->mins[2] = brush->points[i].v[2];
1396                 if(brush->points[i].v[0] > brush->maxs[0]) brush->maxs[0] = brush->points[i].v[0];
1397                 if(brush->points[i].v[1] > brush->maxs[1]) brush->maxs[1] = brush->points[i].v[1];
1398                 if(brush->points[i].v[2] > brush->maxs[2]) brush->maxs[2] = brush->points[i].v[2];
1399         }
1400 }
1401
1402 typedef struct collision_cachedtrace_parameters_s
1403 {
1404         dp_model_t *model;
1405         vec3_t end;
1406         vec3_t start;
1407         int hitsupercontentsmask;
1408         matrix4x4_t matrix;
1409 }
1410 collision_cachedtrace_parameters_t;
1411
1412 typedef struct collision_cachedtrace_s
1413 {
1414         qboolean valid;
1415         collision_cachedtrace_parameters_t p;
1416         trace_t result;
1417 }
1418 collision_cachedtrace_t;
1419
1420 static mempool_t *collision_cachedtrace_mempool;
1421 static collision_cachedtrace_t *collision_cachedtrace_array;
1422 static int collision_cachedtrace_firstfree;
1423 static int collision_cachedtrace_lastused;
1424 static int collision_cachedtrace_max;
1425 static int collision_cachedtrace_sequence;
1426 static int collision_cachedtrace_hashsize;
1427 static int *collision_cachedtrace_hash;
1428 static unsigned int *collision_cachedtrace_arrayfullhashindex;
1429 static unsigned int *collision_cachedtrace_arrayhashindex;
1430 static unsigned int *collision_cachedtrace_arraynext;
1431 static unsigned char *collision_cachedtrace_arrayused;
1432 static qboolean collision_cachedtrace_rebuildhash;
1433
1434 void Collision_Cache_Reset(qboolean resetlimits)
1435 {
1436         if (collision_cachedtrace_hash)
1437                 Mem_Free(collision_cachedtrace_hash);
1438         if (collision_cachedtrace_array)
1439                 Mem_Free(collision_cachedtrace_array);
1440         if (collision_cachedtrace_arrayfullhashindex)
1441                 Mem_Free(collision_cachedtrace_arrayfullhashindex);
1442         if (collision_cachedtrace_arrayhashindex)
1443                 Mem_Free(collision_cachedtrace_arrayhashindex);
1444         if (collision_cachedtrace_arraynext)
1445                 Mem_Free(collision_cachedtrace_arraynext);
1446         if (collision_cachedtrace_arrayused)
1447                 Mem_Free(collision_cachedtrace_arrayused);
1448         if (resetlimits || !collision_cachedtrace_max)
1449                 collision_cachedtrace_max = collision_cache.integer ? 128 : 1;
1450         collision_cachedtrace_firstfree = 1;
1451         collision_cachedtrace_lastused = 0;
1452         collision_cachedtrace_hashsize = collision_cachedtrace_max;
1453         collision_cachedtrace_array = (collision_cachedtrace_t *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(collision_cachedtrace_t));
1454         collision_cachedtrace_hash = (int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_hashsize * sizeof(int));
1455         collision_cachedtrace_arrayfullhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1456         collision_cachedtrace_arrayhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1457         collision_cachedtrace_arraynext = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1458         collision_cachedtrace_arrayused = (unsigned char *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned char));
1459         collision_cachedtrace_sequence = 1;
1460         collision_cachedtrace_rebuildhash = false;
1461 }
1462
1463 void Collision_Cache_Init(mempool_t *mempool)
1464 {
1465         collision_cachedtrace_mempool = mempool;
1466         Collision_Cache_Reset(true);
1467 }
1468
1469 static void Collision_Cache_RebuildHash(void)
1470 {
1471         int index;
1472         int range = collision_cachedtrace_lastused + 1;
1473         int sequence = collision_cachedtrace_sequence;
1474         int firstfree = collision_cachedtrace_max;
1475         int lastused = 0;
1476         int *hash = collision_cachedtrace_hash;
1477         unsigned int hashindex;
1478         unsigned int *arrayhashindex = collision_cachedtrace_arrayhashindex;
1479         unsigned int *arraynext = collision_cachedtrace_arraynext;
1480         collision_cachedtrace_rebuildhash = false;
1481         memset(collision_cachedtrace_hash, 0, collision_cachedtrace_hashsize * sizeof(int));
1482         for (index = 1;index < range;index++)
1483         {
1484                 if (collision_cachedtrace_arrayused[index] == sequence)
1485                 {
1486                         hashindex = arrayhashindex[index];
1487                         arraynext[index] = hash[hashindex];
1488                         hash[hashindex] = index;
1489                         lastused = index;
1490                 }
1491                 else
1492                 {
1493                         if (firstfree > index)
1494                                 firstfree = index;
1495                         collision_cachedtrace_arrayused[index] = 0;
1496                 }
1497         }
1498         collision_cachedtrace_firstfree = firstfree;
1499         collision_cachedtrace_lastused = lastused;
1500 }
1501
1502 void Collision_Cache_NewFrame(void)
1503 {
1504         if (collision_cache.integer)
1505         {
1506                 if (collision_cachedtrace_max < 128)
1507                         Collision_Cache_Reset(true);
1508         }
1509         else
1510         {
1511                 if (collision_cachedtrace_max > 1)
1512                         Collision_Cache_Reset(true);
1513         }
1514         // rebuild hash if sequence would overflow byte, otherwise increment
1515         if (collision_cachedtrace_sequence == 255)
1516         {
1517                 Collision_Cache_RebuildHash();
1518                 collision_cachedtrace_sequence = 1;
1519         }
1520         else
1521         {
1522                 collision_cachedtrace_rebuildhash = true;
1523                 collision_cachedtrace_sequence++;
1524         }
1525 }
1526
1527 static unsigned int Collision_Cache_HashIndexForArray(unsigned int *array, unsigned int size)
1528 {
1529         unsigned int i;
1530         unsigned int hashindex = 0;
1531         // this is a super-cheesy checksum, designed only for speed
1532         for (i = 0;i < size;i++)
1533                 hashindex += array[i] * (1 + i);
1534         return hashindex;
1535 }
1536
1537 static collision_cachedtrace_t *Collision_Cache_Lookup(dp_model_t *model, const matrix4x4_t *matrix, const matrix4x4_t *inversematrix, const vec3_t start, const vec3_t end, int hitsupercontentsmask)
1538 {
1539         int hashindex = 0;
1540         unsigned int fullhashindex;
1541         int index = 0;
1542         int range;
1543         int sequence = collision_cachedtrace_sequence;
1544         int *hash = collision_cachedtrace_hash;
1545         unsigned int *arrayfullhashindex = collision_cachedtrace_arrayfullhashindex;
1546         unsigned int *arraynext = collision_cachedtrace_arraynext;
1547         collision_cachedtrace_t *cached = collision_cachedtrace_array + index;
1548         collision_cachedtrace_parameters_t params;
1549         // all non-cached traces use the same index
1550         if (!collision_cache.integer)
1551                 r_refdef.stats[r_stat_photoncache_traced]++;
1552         else
1553         {
1554                 // cached trace lookup
1555                 memset(&params, 0, sizeof(params));
1556                 params.model = model;
1557                 VectorCopy(start, params.start);
1558                 VectorCopy(end,   params.end);
1559                 params.hitsupercontentsmask = hitsupercontentsmask;
1560                 params.matrix = *matrix;
1561                 fullhashindex = Collision_Cache_HashIndexForArray((unsigned int *)&params, sizeof(params) / sizeof(unsigned int));
1562                 hashindex = (int)(fullhashindex % (unsigned int)collision_cachedtrace_hashsize);
1563                 for (index = hash[hashindex];index;index = arraynext[index])
1564                 {
1565                         if (arrayfullhashindex[index] != fullhashindex)
1566                                 continue;
1567                         cached = collision_cachedtrace_array + index;
1568                         //if (memcmp(&cached->p, &params, sizeof(params)))
1569                         if (cached->p.model != params.model
1570                          || cached->p.end[0] != params.end[0]
1571                          || cached->p.end[1] != params.end[1]
1572                          || cached->p.end[2] != params.end[2]
1573                          || cached->p.start[0] != params.start[0]
1574                          || cached->p.start[1] != params.start[1]
1575                          || cached->p.start[2] != params.start[2]
1576                          || cached->p.hitsupercontentsmask != params.hitsupercontentsmask
1577                          || cached->p.matrix.m[0][0] != params.matrix.m[0][0]
1578                          || cached->p.matrix.m[0][1] != params.matrix.m[0][1]
1579                          || cached->p.matrix.m[0][2] != params.matrix.m[0][2]
1580                          || cached->p.matrix.m[0][3] != params.matrix.m[0][3]
1581                          || cached->p.matrix.m[1][0] != params.matrix.m[1][0]
1582                          || cached->p.matrix.m[1][1] != params.matrix.m[1][1]
1583                          || cached->p.matrix.m[1][2] != params.matrix.m[1][2]
1584                          || cached->p.matrix.m[1][3] != params.matrix.m[1][3]
1585                          || cached->p.matrix.m[2][0] != params.matrix.m[2][0]
1586                          || cached->p.matrix.m[2][1] != params.matrix.m[2][1]
1587                          || cached->p.matrix.m[2][2] != params.matrix.m[2][2]
1588                          || cached->p.matrix.m[2][3] != params.matrix.m[2][3]
1589                          || cached->p.matrix.m[3][0] != params.matrix.m[3][0]
1590                          || cached->p.matrix.m[3][1] != params.matrix.m[3][1]
1591                          || cached->p.matrix.m[3][2] != params.matrix.m[3][2]
1592                          || cached->p.matrix.m[3][3] != params.matrix.m[3][3]
1593                         )
1594                                 continue;
1595                         // found a matching trace in the cache
1596                         r_refdef.stats[r_stat_photoncache_cached]++;
1597                         cached->valid = true;
1598                         collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
1599                         return cached;
1600                 }
1601                 r_refdef.stats[r_stat_photoncache_traced]++;
1602                 // find an unused cache entry
1603                 for (index = collision_cachedtrace_firstfree, range = collision_cachedtrace_max;index < range;index++)
1604                         if (collision_cachedtrace_arrayused[index] == 0)
1605                                 break;
1606                 if (index == range)
1607                 {
1608                         // all claimed, but probably some are stale...
1609                         for (index = 1, range = collision_cachedtrace_max;index < range;index++)
1610                                 if (collision_cachedtrace_arrayused[index] != sequence)
1611                                         break;
1612                         if (index < range)
1613                         {
1614                                 // found a stale one, rebuild the hash
1615                                 Collision_Cache_RebuildHash();
1616                         }
1617                         else
1618                         {
1619                                 // we need to grow the cache
1620                                 collision_cachedtrace_max *= 2;
1621                                 Collision_Cache_Reset(false);
1622                                 index = 1;
1623                         }
1624                 }
1625                 // link the new cache entry into the hash bucket
1626                 collision_cachedtrace_firstfree = index + 1;
1627                 if (collision_cachedtrace_lastused < index)
1628                         collision_cachedtrace_lastused = index;
1629                 cached = collision_cachedtrace_array + index;
1630                 collision_cachedtrace_arraynext[index] = collision_cachedtrace_hash[hashindex];
1631                 collision_cachedtrace_hash[hashindex] = index;
1632                 collision_cachedtrace_arrayhashindex[index] = hashindex;
1633                 cached->valid = false;
1634                 cached->p = params;
1635                 collision_cachedtrace_arrayfullhashindex[index] = fullhashindex;
1636                 collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
1637         }
1638         return cached;
1639 }
1640
1641 void Collision_Cache_ClipLineToGenericEntitySurfaces(trace_t *trace, dp_model_t *model, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, const vec3_t end, int hitsupercontentsmask)
1642 {
1643         collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, matrix, inversematrix, start, end, hitsupercontentsmask);
1644         if (cached->valid)
1645         {
1646                 *trace = cached->result;
1647                 return;
1648         }
1649
1650         Collision_ClipLineToGenericEntity(trace, model, NULL, NULL, vec3_origin, vec3_origin, 0, matrix, inversematrix, start, end, hitsupercontentsmask, collision_extendmovelength.value, true);
1651
1652         cached->result = *trace;
1653 }
1654
1655 void Collision_Cache_ClipLineToWorldSurfaces(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t end, int hitsupercontents)
1656 {
1657         collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, &identitymatrix, &identitymatrix, start, end, hitsupercontents);
1658         if (cached->valid)
1659         {
1660                 *trace = cached->result;
1661                 return;
1662         }
1663
1664         Collision_ClipLineToWorld(trace, model, start, end, hitsupercontents, collision_extendmovelength.value, true);
1665
1666         cached->result = *trace;
1667 }
1668
1669 typedef struct extendtraceinfo_s
1670 {
1671         trace_t *trace;
1672         float realstart[3];
1673         float realend[3];
1674         float realdelta[3];
1675         float extendstart[3];
1676         float extendend[3];
1677         float extenddelta[3];
1678         float reallength;
1679         float extendlength;
1680         float scaletoextend;
1681         float extend;
1682 }
1683 extendtraceinfo_t;
1684
1685 static void Collision_ClipExtendPrepare(extendtraceinfo_t *extendtraceinfo, trace_t *trace, const vec3_t tstart, const vec3_t tend, float textend)
1686 {
1687         memset(trace, 0, sizeof(*trace));
1688         trace->fraction = 1;
1689
1690         extendtraceinfo->trace = trace;
1691         VectorCopy(tstart, extendtraceinfo->realstart);
1692         VectorCopy(tend, extendtraceinfo->realend);
1693         VectorSubtract(extendtraceinfo->realend, extendtraceinfo->realstart, extendtraceinfo->realdelta);
1694         VectorCopy(extendtraceinfo->realstart, extendtraceinfo->extendstart);
1695         VectorCopy(extendtraceinfo->realend, extendtraceinfo->extendend);
1696         VectorCopy(extendtraceinfo->realdelta, extendtraceinfo->extenddelta);
1697         extendtraceinfo->reallength = VectorLength(extendtraceinfo->realdelta);
1698         extendtraceinfo->extendlength = extendtraceinfo->reallength;
1699         extendtraceinfo->scaletoextend = 1.0f;
1700         extendtraceinfo->extend = textend;
1701
1702         // make the trace longer according to the extend parameter
1703         if (extendtraceinfo->reallength && extendtraceinfo->extend)
1704         {
1705                 extendtraceinfo->extendlength = extendtraceinfo->reallength + extendtraceinfo->extend;
1706                 extendtraceinfo->scaletoextend = extendtraceinfo->extendlength / extendtraceinfo->reallength;
1707                 VectorMA(extendtraceinfo->realstart, extendtraceinfo->scaletoextend, extendtraceinfo->realdelta, extendtraceinfo->extendend);
1708                 VectorSubtract(extendtraceinfo->extendend, extendtraceinfo->extendstart, extendtraceinfo->extenddelta);
1709         }
1710 }
1711
1712 static void Collision_ClipExtendFinish(extendtraceinfo_t *extendtraceinfo)
1713 {
1714         trace_t *trace = extendtraceinfo->trace;
1715
1716         if (trace->fraction != 1.0f)
1717         {
1718                 // undo the extended trace length
1719                 trace->fraction *= extendtraceinfo->scaletoextend;
1720
1721                 // if the extended trace hit something that the unextended trace did not hit (even considering the collision_impactnudge), then we have to clear the hit information
1722                 if (trace->fraction > 1.0f)
1723                 {
1724                         // note that ent may refer to either startsolid or fraction<1, we can't restore the startsolid ent unfortunately
1725                         trace->ent = NULL;
1726                         trace->hitq3surfaceflags = 0;
1727                         trace->hitsupercontents = 0;
1728                         trace->hittexture = NULL;
1729                         VectorClear(trace->plane.normal);
1730                         trace->plane.dist = 0.0f;
1731                 }
1732         }
1733
1734         // clamp things
1735         trace->fraction = bound(0, trace->fraction, 1);
1736
1737         // calculate the end position
1738         VectorMA(extendtraceinfo->realstart, trace->fraction, extendtraceinfo->realdelta, trace->endpos);
1739 }
1740
1741 void Collision_ClipToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t tstart, const vec3_t mins, const vec3_t maxs, const vec3_t tend, int hitsupercontentsmask, float extend)
1742 {
1743         vec3_t starttransformed, endtransformed;
1744         extendtraceinfo_t extendtraceinfo;
1745         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1746
1747         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
1748         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
1749 #if COLLISIONPARANOID >= 3
1750         Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", extendtraceinfo.extendstart[0], extendtraceinfo.extendstart[1], extendtraceinfo.extendstart[2], starttransformed[0], starttransformed[1], starttransformed[2], extendtraceinfo.extendend[0], extendtraceinfo.extendend[1], extendtraceinfo.extendend[2], endtransformed[0], endtransformed[1], endtransformed[2]);
1751 #endif
1752
1753         if (model && model->TraceBox)
1754         {
1755                 if(model->TraceBrush && (inversematrix->m[0][1] || inversematrix->m[0][2] || inversematrix->m[1][0] || inversematrix->m[1][2] || inversematrix->m[2][0] || inversematrix->m[2][1]))
1756                 {
1757                         // we get here if TraceBrush exists, AND we have a rotation component (SOLID_BSP case)
1758                         // using starttransformed, endtransformed is WRONG in this case!
1759                         // should rather build a brush and trace using it
1760                         colboxbrushf_t thisbrush_start, thisbrush_end;
1761                         Collision_BrushForBox(&thisbrush_start, mins, maxs, 0, 0, NULL);
1762                         Collision_BrushForBox(&thisbrush_end, mins, maxs, 0, 0, NULL);
1763                         Collision_TranslateBrush(extendtraceinfo.extendstart, &thisbrush_start.brush);
1764                         Collision_TranslateBrush(extendtraceinfo.extendend, &thisbrush_end.brush);
1765                         Collision_TransformBrush(inversematrix, &thisbrush_start.brush);
1766                         Collision_TransformBrush(inversematrix, &thisbrush_end.brush);
1767                         //Collision_TranslateBrush(starttransformed, &thisbrush_start.brush);
1768                         //Collision_TranslateBrush(endtransformed, &thisbrush_end.brush);
1769                         model->TraceBrush(model, frameblend, skeleton, trace, &thisbrush_start.brush, &thisbrush_end.brush, hitsupercontentsmask);
1770                 }
1771                 else // this is only approximate if rotated, quite useless
1772                         model->TraceBox(model, frameblend, skeleton, trace, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask);
1773         }
1774         else // and this requires that the transformation matrix doesn't have angles components, like SV_TraceBox ensures; FIXME may get called if a model is SOLID_BSP but has no TraceBox function
1775                 Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1776
1777         Collision_ClipExtendFinish(&extendtraceinfo);
1778
1779         // transform plane
1780         // NOTE: this relies on plane.dist being directly after plane.normal
1781         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1782 }
1783
1784 void Collision_ClipToWorld(trace_t *trace, dp_model_t *model, const vec3_t tstart, const vec3_t mins, const vec3_t maxs, const vec3_t tend, int hitsupercontents, float extend)
1785 {
1786         extendtraceinfo_t extendtraceinfo;
1787         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1788         // ->TraceBox: TraceBrush not needed here, as worldmodel is never rotated
1789         if (model && model->TraceBox)
1790                 model->TraceBox(model, NULL, NULL, trace, extendtraceinfo.extendstart, mins, maxs, extendtraceinfo.extendend, hitsupercontents);
1791         Collision_ClipExtendFinish(&extendtraceinfo);
1792 }
1793
1794 void Collision_ClipLineToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t tstart, const vec3_t tend, int hitsupercontentsmask, float extend, qboolean hitsurfaces)
1795 {
1796         vec3_t starttransformed, endtransformed;
1797         extendtraceinfo_t extendtraceinfo;
1798         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1799
1800         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
1801         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
1802 #if COLLISIONPARANOID >= 3
1803         Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", extendtraceinfo.extendstart[0], extendtraceinfo.extendstart[1], extendtraceinfo.extendstart[2], starttransformed[0], starttransformed[1], starttransformed[2], extendtraceinfo.extendend[0], extendtraceinfo.extendend[1], extendtraceinfo.extendend[2], endtransformed[0], endtransformed[1], endtransformed[2]);
1804 #endif
1805
1806         if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
1807                 model->TraceLineAgainstSurfaces(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask);
1808         else if (model && model->TraceLine)
1809                 model->TraceLine(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask);
1810         else
1811                 Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, vec3_origin, vec3_origin, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1812
1813         Collision_ClipExtendFinish(&extendtraceinfo);
1814
1815         // transform plane
1816         // NOTE: this relies on plane.dist being directly after plane.normal
1817         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1818 }
1819
1820 void Collision_ClipLineToWorld(trace_t *trace, dp_model_t *model, const vec3_t tstart, const vec3_t tend, int hitsupercontents, float extend, qboolean hitsurfaces)
1821 {
1822         extendtraceinfo_t extendtraceinfo;
1823         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1824
1825         if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
1826                 model->TraceLineAgainstSurfaces(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontents);
1827         else if (model && model->TraceLine)
1828                 model->TraceLine(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontents);
1829
1830         Collision_ClipExtendFinish(&extendtraceinfo);
1831 }
1832
1833 void Collision_ClipPointToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, int hitsupercontentsmask)
1834 {
1835         float starttransformed[3];
1836         memset(trace, 0, sizeof(*trace));
1837         trace->fraction = 1;
1838
1839         Matrix4x4_Transform(inversematrix, start, starttransformed);
1840 #if COLLISIONPARANOID >= 3
1841         Con_Printf("trans(%f %f %f -> %f %f %f)", start[0], start[1], start[2], starttransformed[0], starttransformed[1], starttransformed[2]);
1842 #endif
1843
1844         if (model && model->TracePoint)
1845                 model->TracePoint(model, NULL, NULL, trace, starttransformed, hitsupercontentsmask);
1846         else
1847                 Collision_ClipTrace_Point(trace, bodymins, bodymaxs, starttransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1848
1849         VectorCopy(start, trace->endpos);
1850         // transform plane
1851         // NOTE: this relies on plane.dist being directly after plane.normal
1852         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1853 }
1854
1855 void Collision_ClipPointToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, int hitsupercontents)
1856 {
1857         memset(trace, 0, sizeof(*trace));
1858         trace->fraction = 1;
1859         if (model && model->TracePoint)
1860                 model->TracePoint(model, NULL, NULL, trace, start, hitsupercontents);
1861         VectorCopy(start, trace->endpos);
1862 }
1863
1864 void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *touch, qboolean isbmodel)
1865 {
1866         // take the 'best' answers from the new trace and combine with existing data
1867         if (trace->allsolid)
1868                 cliptrace->allsolid = true;
1869         if (trace->startsolid)
1870         {
1871                 if (isbmodel)
1872                         cliptrace->bmodelstartsolid = true;
1873                 cliptrace->startsolid = true;
1874                 if (cliptrace->fraction == 1)
1875                         cliptrace->ent = touch;
1876                 if (cliptrace->startdepth > trace->startdepth)
1877                 {
1878                         cliptrace->startdepth = trace->startdepth;
1879                         VectorCopy(trace->startdepthnormal, cliptrace->startdepthnormal);
1880                 }
1881         }
1882         // don't set this except on the world, because it can easily confuse
1883         // monsters underwater if there's a bmodel involved in the trace
1884         // (inopen && inwater is how they check water visibility)
1885         //if (trace->inopen)
1886         //      cliptrace->inopen = true;
1887         if (trace->inwater)
1888                 cliptrace->inwater = true;
1889         if ((trace->fraction < cliptrace->fraction) && (VectorLength2(trace->plane.normal) > 0))
1890         {
1891                 cliptrace->fraction = trace->fraction;
1892                 VectorCopy(trace->endpos, cliptrace->endpos);
1893                 cliptrace->plane = trace->plane;
1894                 cliptrace->ent = touch;
1895                 cliptrace->hitsupercontents = trace->hitsupercontents;
1896                 cliptrace->hitq3surfaceflags = trace->hitq3surfaceflags;
1897                 cliptrace->hittexture = trace->hittexture;
1898         }
1899         cliptrace->startsupercontents |= trace->startsupercontents;
1900 }