]> de.git.xonotic.org Git - xonotic/darkplaces.git/blobdiff - collision.c
made darkplaces compile successfully with g++ to test for errors C doesn't care about...
[xonotic/darkplaces.git] / collision.c
index b95ab4087a7d46b712a8924db35c69b62f84af03..be5fd1ba01339775dd3a27b5dadc0c3fcc7e43df 100644 (file)
 
 #include "quakedef.h"
-#include "winding.h"
+#include "polygon.h"
 
-typedef struct
-{
-       // the hull we're tracing through
-       const hull_t *hull;
-
-       // the trace structure to fill in
-       trace_t *trace;
-
-       // start and end of the trace (in model space)
-       double start[3];
-       double end[3];
-
-       // end - start
-       double dist[3];
-
-       // overrides the CONTENTS_SOLID in the box bsp tree
-       int boxsupercontents;
-}
-RecursiveHullCheckTraceInfo_t;
-
-// 1/32 epsilon to keep floating point happy
-#define DIST_EPSILON (0.03125)
-
-#define HULLCHECKSTATE_EMPTY 0
-#define HULLCHECKSTATE_SOLID 1
-#define HULLCHECKSTATE_DONE 2
-
-static int RecursiveHullCheck(RecursiveHullCheckTraceInfo_t *t, int num, double p1f, double p2f, double p1[3], double p2[3])
-{
-       // status variables, these don't need to be saved on the stack when
-       // recursing...  but are because this should be thread-safe
-       // (note: tracing against a bbox is not thread-safe, yet)
-       int ret;
-       mplane_t *plane;
-       double t1, t2;
-
-       // variables that need to be stored on the stack when recursing
-       dclipnode_t *node;
-       int side;
-       double midf, mid[3];
-
-       // LordHavoc: a goto!  everyone flee in terror... :)
-loc0:
-       // check for empty
-       if (num < 0)
-       {
-               // translate the fake CONTENTS values in the box bsp tree
-               if (num == CONTENTS_SOLID)
-                       num = t->boxsupercontents;
-               else
-                       num = 0;
-               if (!t->trace->startfound)
-               {
-                       t->trace->startfound = true;
-                       t->trace->startsupercontents |= num;
-               }
-               if (num & t->trace->hitsupercontentsmask)
-               {
-                       // if the first leaf is solid, set startsolid
-                       if (t->trace->allsolid)
-                               t->trace->startsolid = true;
-                       return HULLCHECKSTATE_SOLID;
-               }
-               else
-               {
-                       t->trace->allsolid = false;
-                       return HULLCHECKSTATE_EMPTY;
-               }
-       }
-
-       // find the point distances
-       node = t->hull->clipnodes + num;
+#define COLLISION_SNAPSCALE (8.0f)
+#define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
 
-       plane = t->hull->planes + node->planenum;
-       if (plane->type < 3)
-       {
-               t1 = p1[plane->type] - plane->dist;
-               t2 = p2[plane->type] - plane->dist;
-       }
-       else
-       {
-               t1 = DotProduct (plane->normal, p1) - plane->dist;
-               t2 = DotProduct (plane->normal, p2) - plane->dist;
-       }
-
-       if (t1 < 0)
-       {
-               if (t2 < 0)
-               {
-                       num = node->children[1];
-                       goto loc0;
-               }
-               side = 1;
-       }
-       else
-       {
-               if (t2 >= 0)
-               {
-                       num = node->children[0];
-                       goto loc0;
-               }
-               side = 0;
-       }
-
-       // the line intersects, find intersection point
-       // LordHavoc: this uses the original trace for maximum accuracy
-       if (plane->type < 3)
-       {
-               t1 = t->start[plane->type] - plane->dist;
-               t2 = t->end[plane->type] - plane->dist;
-       }
-       else
-       {
-               t1 = DotProduct (plane->normal, t->start) - plane->dist;
-               t2 = DotProduct (plane->normal, t->end) - plane->dist;
-       }
-
-       midf = t1 / (t1 - t2);
-       midf = bound(p1f, midf, p2f);
-       VectorMA(t->start, midf, t->dist, mid);
-
-       // recurse both sides, front side first
-       ret = RecursiveHullCheck (t, node->children[side], p1f, midf, p1, mid);
-       // if this side is not empty, return what it is (solid or done)
-       if (ret != HULLCHECKSTATE_EMPTY)
-               return ret;
-
-       ret = RecursiveHullCheck (t, node->children[side ^ 1], midf, p2f, mid, p2);
-       // if other side is not solid, return what it is (empty or done)
-       if (ret != HULLCHECKSTATE_SOLID)
-               return ret;
-
-       // front is air and back is solid, this is the impact point...
-       if (side)
-       {
-               t->trace->plane.dist = -plane->dist;
-               VectorNegate (plane->normal, t->trace->plane.normal);
-       }
-       else
-       {
-               t->trace->plane.dist = plane->dist;
-               VectorCopy (plane->normal, t->trace->plane.normal);
-       }
-
-       // bias away from surface a bit
-       t1 = DotProduct(t->trace->plane.normal, t->start) - (t->trace->plane.dist + DIST_EPSILON);
-       t2 = DotProduct(t->trace->plane.normal, t->end) - (t->trace->plane.dist + DIST_EPSILON);
-
-       midf = t1 / (t1 - t2);
-       t->trace->fraction = bound(0.0f, midf, 1.0);
-
-       return HULLCHECKSTATE_DONE;
-}
-
-#if 0
-// used if start and end are the same
-static void RecursiveHullCheckPoint (RecursiveHullCheckTraceInfo_t *t, int num)
-{
-       // If you can read this, you understand BSP trees
-       while (num >= 0)
-               num = t->hull->clipnodes[num].children[((t->hull->planes[t->hull->clipnodes[num].planenum].type < 3) ? (t->start[t->hull->planes[t->hull->clipnodes[num].planenum].type]) : (DotProduct(t->hull->planes[t->hull->clipnodes[num].planenum].normal, t->start))) < t->hull->planes[t->hull->clipnodes[num].planenum].dist];
-
-       // check for empty
-       t->trace->endcontents = num;
-       if (t->trace->thiscontents)
-       {
-               if (num == t->trace->thiscontents)
-                       t->trace->allsolid = false;
-               else
-               {
-                       // if the first leaf is solid, set startsolid
-                       if (t->trace->allsolid)
-                               t->trace->startsolid = true;
-               }
-       }
-       else
-       {
-               if (num != CONTENTS_SOLID)
-               {
-                       t->trace->allsolid = false;
-                       if (num == CONTENTS_EMPTY)
-                               t->trace->inopen = true;
-                       else
-                               t->trace->inwater = true;
-               }
-               else
-               {
-                       // if the first leaf is solid, set startsolid
-                       if (t->trace->allsolid)
-                               t->trace->startsolid = true;
-               }
-       }
-}
-#endif
-
-static hull_t box_hull;
-static dclipnode_t box_clipnodes[6];
-static mplane_t box_planes[6];
+cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125"};
+cvar_t collision_startnudge = {0, "collision_startnudge", "0"};
+cvar_t collision_endnudge = {0, "collision_endnudge", "0"};
+cvar_t collision_enternudge = {0, "collision_enternudge", "0"};
+cvar_t collision_leavenudge = {0, "collision_leavenudge", "0"};
 
 void Collision_Init (void)
 {
-       int             i;
-       int             side;
-
-       //Set up the planes and clipnodes so that the six floats of a bounding box
-       //can just be stored out and get a proper hull_t structure.
-
-       box_hull.clipnodes = box_clipnodes;
-       box_hull.planes = box_planes;
-       box_hull.firstclipnode = 0;
-       box_hull.lastclipnode = 5;
-
-       for (i = 0;i < 6;i++)
-       {
-               box_clipnodes[i].planenum = i;
-
-               side = i&1;
-
-               box_clipnodes[i].children[side] = CONTENTS_EMPTY;
-               if (i != 5)
-                       box_clipnodes[i].children[side^1] = i + 1;
-               else
-                       box_clipnodes[i].children[side^1] = CONTENTS_SOLID;
-
-               box_planes[i].type = i>>1;
-               box_planes[i].normal[i>>1] = 1;
-       }
-}
-
-void Collision_ClipTrace_Box(trace_t *trace, const vec3_t cmins, const vec3_t cmaxs, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask, int boxsupercontents)
-{
-       RecursiveHullCheckTraceInfo_t rhc;
-       // fill in a default trace
-       memset(&rhc, 0, sizeof(rhc));
-       memset(trace, 0, sizeof(trace_t));
-       //To keep everything totally uniform, bounding boxes are turned into small
-       //BSP trees instead of being compared directly.
-       // create a temp hull from bounding box sizes
-       box_planes[0].dist = cmaxs[0] - mins[0];
-       box_planes[1].dist = cmins[0] - maxs[0];
-       box_planes[2].dist = cmaxs[1] - mins[1];
-       box_planes[3].dist = cmins[1] - maxs[1];
-       box_planes[4].dist = cmaxs[2] - mins[2];
-       box_planes[5].dist = cmins[2] - maxs[2];
-       // trace a line through the generated clipping hull
-       rhc.boxsupercontents = boxsupercontents;
-       rhc.hull = &box_hull;
-       rhc.trace = trace;
-       rhc.trace->hitsupercontentsmask = hitsupercontentsmask;
-       rhc.trace->fraction = 1;
-       rhc.trace->allsolid = true;
-       VectorCopy(start, rhc.start);
-       VectorCopy(end, rhc.end);
-       VectorSubtract(rhc.end, rhc.start, rhc.dist);
-       RecursiveHullCheck(&rhc, rhc.hull->firstclipnode, 0, 1, rhc.start, rhc.end);
-       VectorMA(rhc.start, rhc.trace->fraction, rhc.dist, rhc.trace->endpos);
+       Cvar_RegisterVariable(&collision_impactnudge);
+       Cvar_RegisterVariable(&collision_startnudge);
+       Cvar_RegisterVariable(&collision_endnudge);
+       Cvar_RegisterVariable(&collision_enternudge);
+       Cvar_RegisterVariable(&collision_leavenudge);
 }
 
 
@@ -273,7 +33,6 @@ void Collision_ClipTrace_Box(trace_t *trace, const vec3_t cmins, const vec3_t cm
 
 
 
-
 void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
 {
        int i;
@@ -288,30 +47,33 @@ void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
 
 void Collision_ValidateBrush(colbrushf_t *brush)
 {
-       int j, k, pointsoffplanes, printbrush;
+       int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
        float d;
        printbrush = false;
        if (!brush->numpoints)
        {
-               Con_Printf("Collision_ValidateBrush: brush with no points!\n");
+               Con_Print("Collision_ValidateBrush: brush with no points!\n");
                printbrush = true;
        }
 #if 0
        // it's ok for a brush to have one point and no planes...
        if (brush->numplanes == 0 && brush->numpoints != 1)
        {
-               Con_Printf("Collision_ValidateBrush: brush with no planes and more than one point!\n");
+               Con_Print("Collision_ValidateBrush: brush with no planes and more than one point!\n");
                printbrush = true;
        }
 #endif
        if (brush->numplanes)
        {
                pointsoffplanes = 0;
+               pointswithinsufficientplanes = 0;
                for (k = 0;k < brush->numplanes;k++)
-               {
                        if (DotProduct(brush->planes[k].normal, brush->planes[k].normal) < 0.0001f)
                                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);
-                       for (j = 0;j < brush->numpoints;j++)
+               for (j = 0;j < brush->numpoints;j++)
+               {
+                       pointonplanes = 0;
+                       for (k = 0;k < brush->numplanes;k++)
                        {
                                d = DotProduct(brush->points[j].v, brush->planes[k].normal) - brush->planes[k].dist;
                                if (d > (1.0f / 8.0f))
@@ -319,13 +81,22 @@ void Collision_ValidateBrush(colbrushf_t *brush)
                                        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);
                                        printbrush = true;
                                }
-                               if (fabs(d) > 0.01f)
+                               if (fabs(d) > 0.125f)
                                        pointsoffplanes++;
+                               else
+                                       pointonplanes++;
                        }
+                       if (pointonplanes < 3)
+                               pointswithinsufficientplanes++;
+               }
+               if (pointswithinsufficientplanes)
+               {
+                       Con_Print("Collision_ValidateBrush: some points have insufficient planes, every point must be on at least 3 planes to form a corner.\n");
+                       printbrush = true;
                }
                if (pointsoffplanes == 0) // all points are on all planes
                {
-                       Con_Printf("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
+                       Con_Print("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
                        printbrush = true;
                }
        }
@@ -362,154 +133,186 @@ float furthestplanedist_float(const float *normal, const colpointf_t *points, in
 }
 
 
-colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const mplane_t *originalplanes, int supercontents, winding_t *temp1, winding_t *temp2)
+colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const mplane_t *originalplanes, int supercontents)
 {
-       int j, k, m;
-       int numpoints, maxpoints, numplanes, maxplanes, numelements, maxelements, numtriangles, numpolypoints, maxpolypoints;
-       winding_t *w, *temp, *othertemp;
+       int j, k, m, w;
+       int numpointsbuf = 0, maxpointsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
        colbrushf_t *brush;
        colpointf_t pointsbuf[256];
        colplanef_t planesbuf[256];
        int elementsbuf[1024];
        int polypointbuf[256];
-       float mins[3], maxs[3];
+       int pmaxpoints = 64;
+       int pnumpoints;
+       double p[2][3*64];
+#if 0
+       // enable these if debugging to avoid seeing garbage in unused data
+       memset(pointsbuf, 0, sizeof(pointsbuf));
+       memset(planesbuf, 0, sizeof(planesbuf));
+       memset(elementsbuf, 0, sizeof(elementsbuf));
+       memset(polypointbuf, 0, sizeof(polypointbuf));
+       memset(p, 0, sizeof(p));
+#endif
        // construct a collision brush (points, planes, and renderable mesh) from
        // a set of planes, this also optimizes out any unnecessary planes (ones
        // whose polygon is clipped away by the other planes)
-       numpoints = 0;maxpoints = 256;
-       numplanes = 0;maxplanes = 256;
-       numelements = 0;maxelements = 1024;
-       numtriangles = 0;
-       maxpolypoints = 256;
        for (j = 0;j < numoriginalplanes;j++)
        {
                // add the plane uniquely (no duplicates)
-               for (k = 0;k < numplanes;k++)
+               for (k = 0;k < numplanesbuf;k++)
                        if (VectorCompare(planesbuf[k].normal, originalplanes[j].normal) && planesbuf[k].dist == originalplanes[j].dist)
                                break;
                // if the plane is a duplicate, skip it
-               if (k < numplanes)
+               if (k < numplanesbuf)
                        continue;
                // check if there are too many and skip the brush
-               if (numplanes >= 256)
+               if (numplanesbuf >= maxplanesbuf)
                {
-                       Con_Printf("Mod_Q3BSP_LoadBrushes: failed to build collision brush: too many planes for buffer\n");
+                       Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
                        return NULL;
                }
 
                // create a large polygon from the plane
-               w = temp1;
-               othertemp = temp2;
-               BufWinding_NewFromPlane(w, originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist);
+               w = 0;
+               PolygonD_QuadForPlane(p[w], originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist, 1024.0*1024.0*1024.0);
+               pnumpoints = 4;
                // clip it by all other planes
-               for (k = 0;k < numoriginalplanes && w->numpoints;k++)
+               for (k = 0;k < numoriginalplanes && pnumpoints && pnumpoints <= pmaxpoints;k++)
                {
                        if (k != j)
                        {
                                // we want to keep the inside of the brush plane so we flip
                                // the cutting plane
-                               BufWinding_Divide(w, -originalplanes[k].normal[0], -originalplanes[k].normal[1], -originalplanes[k].normal[2], -originalplanes[k].dist, othertemp, NULL, NULL, NULL);
-                               temp = w;
-                               w = othertemp;
-                               othertemp = temp;
+                               PolygonD_Divide(pnumpoints, p[w], -originalplanes[k].normal[0], -originalplanes[k].normal[1], -originalplanes[k].normal[2], -originalplanes[k].dist, 1.0/32.0, pmaxpoints, p[!w], &pnumpoints, 0, NULL, NULL);
+                               w = !w;
                        }
                }
                // if nothing is left, skip it
-               if (!w->numpoints)
+               if (pnumpoints < 3)
+               {
+                       //Con_Printf("Collision_NewBrushFromPlanes: warning: polygon for plane %f %f %f %f clipped away\n", originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist);
                        continue;
+               }
 
-               // copy off the number of points for later when the winding is freed
-               numpolypoints = w->numpoints;
+               for (k = 0;k < pnumpoints;k++)
+               {
+                       int l, m;
+                       m = 0;
+                       for (l = 0;l < numoriginalplanes;l++)
+                               if (fabs(DotProduct(&p[w][k*3], originalplanes[l].normal) - originalplanes[l].dist) < 1.0/8.0)
+                                       m++;
+                       if (m < 3)
+                               break;
+               }
+               if (k < pnumpoints)
+               {
+                       Con_Printf("Collision_NewBrushFromPlanes: warning: polygon point does not lie on at least 3 planes\n");
+                       //return NULL;
+               }
 
                // check if there are too many polygon vertices for buffer
-               if (numpolypoints > maxpolypoints)
+               if (pnumpoints > pmaxpoints)
                {
-                       Con_Printf("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
+                       Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
                        return NULL;
                }
 
                // check if there are too many triangle elements for buffer
-               if (numelements + (w->numpoints - 2) * 3 > maxelements)
+               if (numelementsbuf + (pnumpoints - 2) * 3 > maxelementsbuf)
                {
-                       Con_Printf("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
+                       Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
                        return NULL;
                }
 
-               for (k = 0;k < w->numpoints;k++)
+               for (k = 0;k < pnumpoints;k++)
                {
                        // check if there is already a matching point (no duplicates)
-                       for (m = 0;m < numpoints;m++)
-                               if (VectorDistance2(w->points[k], pointsbuf[m].v) < DIST_EPSILON)
+                       for (m = 0;m < numpointsbuf;m++)
+                               if (VectorDistance2(&p[w][k*3], pointsbuf[m].v) < COLLISION_SNAP)
                                        break;
 
                        // if there is no match, add a new one
-                       if (m == numpoints)
+                       if (m == numpointsbuf)
                        {
                                // check if there are too many and skip the brush
-                               if (numpoints >= 256)
+                               if (numpointsbuf >= maxpointsbuf)
                                {
-                                       Con_Printf("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
-                                       Winding_Free(w);
+                                       Con_Print("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
                                        return NULL;
                                }
                                // add the new one
-                               VectorCopy(w->points[k], pointsbuf[numpoints].v);
-                               numpoints++;
+                               VectorCopy(&p[w][k*3], pointsbuf[numpointsbuf].v);
+                               numpointsbuf++;
                        }
 
                        // store the index into a buffer
                        polypointbuf[k] = m;
                }
-               w = NULL;
-               othertemp = NULL;
-               temp = NULL;
 
                // add the triangles for the polygon
                // (this particular code makes a triangle fan)
-               for (k = 0;k < numpolypoints - 2;k++)
+               for (k = 0;k < pnumpoints - 2;k++)
                {
-                       numtriangles++;
-                       elementsbuf[numelements++] = polypointbuf[0];
-                       elementsbuf[numelements++] = polypointbuf[k + 1];
-                       elementsbuf[numelements++] = polypointbuf[k + 2];
+                       elementsbuf[numelementsbuf++] = polypointbuf[0];
+                       elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
+                       elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
                }
 
                // add the new plane
-               VectorCopy(originalplanes[j].normal, planesbuf[numplanes].normal);
-               planesbuf[numplanes].dist = originalplanes[j].dist;
-               numplanes++;
+               VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
+               planesbuf[numplanesbuf].dist = originalplanes[j].dist;
+               numplanesbuf++;
        }
 
-       // recalc distances
-       for (j = 0;j < numplanes;j++)
-               planesbuf[j].dist = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpoints);
-
-       if (numpoints)
+       // validate plane distances
+       for (j = 0;j < numplanesbuf;j++)
        {
-               VectorCopy(pointsbuf[0].v, mins);
-               VectorCopy(pointsbuf[0].v, maxs);
-               for (j = 1;j < numpoints;j++)
-               {
-                       mins[0] = min(mins[0], pointsbuf[j].v[0]);
-                       mins[1] = min(mins[1], pointsbuf[j].v[1]);
-                       mins[2] = min(mins[2], pointsbuf[j].v[2]);
-                       maxs[0] = max(maxs[0], pointsbuf[j].v[0]);
-                       maxs[1] = max(maxs[1], pointsbuf[j].v[1]);
-                       maxs[2] = max(maxs[2], pointsbuf[j].v[2]);
-               }
+               float d = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpointsbuf);
+               if (fabs(planesbuf[j].dist - d) > (1.0f/32.0f))
+                       Con_Printf("plane %f %f %f %f mismatches dist %f\n", planesbuf[j].normal[0], planesbuf[j].normal[1], planesbuf[j].normal[2], planesbuf[j].dist, d);
        }
 
        // if nothing is left, there's nothing to allocate
-       if (numtriangles < 4 || numplanes < 4 || numpoints < 4)
+       if (numelementsbuf < 12 || numplanesbuf < 4 || numpointsbuf < 4)
+       {
+               Con_Printf("Collision_NewBrushFromPlanes: failed to build collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
                return NULL;
+       }
 
        // allocate the brush and copy to it
-       brush = Collision_AllocBrushFloat(mempool, numpoints, numplanes, numtriangles, supercontents);
-       memcpy(brush->points, pointsbuf, numpoints * sizeof(colpointf_t));
-       memcpy(brush->planes, planesbuf, numplanes * sizeof(colplanef_t));
-       memcpy(brush->elements, elementsbuf, numtriangles * sizeof(int[3]));
-       VectorCopy(mins, brush->mins);
-       VectorCopy(maxs, brush->maxs);
+       brush = Collision_AllocBrushFloat(mempool, numpointsbuf, numplanesbuf, numelementsbuf / 3, supercontents);
+       for (j = 0;j < brush->numpoints;j++)
+       {
+               brush->points[j].v[0] = pointsbuf[j].v[0];
+               brush->points[j].v[1] = pointsbuf[j].v[1];
+               brush->points[j].v[2] = pointsbuf[j].v[2];
+       }
+       for (j = 0;j < brush->numplanes;j++)
+       {
+               brush->planes[j].normal[0] = planesbuf[j].normal[0];
+               brush->planes[j].normal[1] = planesbuf[j].normal[1];
+               brush->planes[j].normal[2] = planesbuf[j].normal[2];
+               brush->planes[j].dist = planesbuf[j].dist;
+       }
+       for (j = 0;j < brush->numtriangles * 3;j++)
+               brush->elements[j] = elementsbuf[j];
+       VectorCopy(brush->points[0].v, brush->mins);
+       VectorCopy(brush->points[0].v, brush->maxs);
+       for (j = 1;j < brush->numpoints;j++)
+       {
+               brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
+               brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
+               brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
+               brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
+               brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
+               brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
+       }
+       brush->mins[0] -= 1;
+       brush->mins[1] -= 1;
+       brush->mins[2] -= 1;
+       brush->maxs[0] += 1;
+       brush->maxs[1] += 1;
+       brush->maxs[2] += 1;
        Collision_ValidateBrush(brush);
        return brush;
 }
@@ -519,23 +322,24 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
 colbrushf_t *Collision_AllocBrushFloat(mempool_t *mempool, int numpoints, int numplanes, int numtriangles, int supercontents)
 {
        colbrushf_t *brush;
-       brush = Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpoints + sizeof(colplanef_t) * numplanes + sizeof(int[3]) * numtriangles);
+       brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpoints + sizeof(colplanef_t) * numplanes + sizeof(int[3]) * numtriangles);
        brush->supercontents = supercontents;
        brush->numplanes = numplanes;
        brush->numpoints = numpoints;
        brush->numtriangles = numtriangles;
-       brush->planes = (void *)(brush + 1);
-       brush->points = (void *)(brush->planes + brush->numplanes);
-       brush->elements = (void *)(brush->points + brush->numpoints);
+       brush->planes = (colplanef_t *)(brush + 1);
+       brush->points = (colpointf_t *)(brush->planes + brush->numplanes);
+       brush->elements = (int *)(brush->points + brush->numpoints);
        return brush;
 }
 
 void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
 {
        int i;
-       float edge0[3], edge1[3], edge2[3], normal[3], dist, bestdist, temp[3];
+       float edge0[3], edge1[3], edge2[3], normal[3], dist, bestdist;
        colpointf_t *p, *p2;
 
+       // FIXME: these probably don't actually need to be normalized if the collision code does not care
        if (brush->numpoints == 3)
        {
                // optimized triangle case
@@ -556,9 +360,42 @@ void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
                        VectorSubtract(brush->points[2].v, brush->points[0].v, edge0);
                        VectorSubtract(brush->points[0].v, brush->points[1].v, edge1);
                        VectorSubtract(brush->points[1].v, brush->points[2].v, edge2);
+#if 1
+                       {
+                               float projectionnormal[3], projectionedge0[3], projectionedge1[3], projectionedge2[3];
+                               int i, best;
+                               float dist, bestdist;
+                               bestdist = fabs(brush->planes[0].normal[0]);
+                               best = 0;
+                               for (i = 1;i < 3;i++)
+                               {
+                                       dist = fabs(brush->planes[0].normal[i]);
+                                       if (bestdist < dist)
+                                       {
+                                               bestdist = dist;
+                                               best = i;
+                                       }
+                               }
+                               VectorClear(projectionnormal);
+                               if (brush->planes[0].normal[best] < 0)
+                                       projectionnormal[best] = -1;
+                               else
+                                       projectionnormal[best] = 1;
+                               VectorCopy(edge0, projectionedge0);
+                               VectorCopy(edge1, projectionedge1);
+                               VectorCopy(edge2, projectionedge2);
+                               projectionedge0[best] = 0;
+                               projectionedge1[best] = 0;
+                               projectionedge2[best] = 0;
+                               CrossProduct(projectionedge0, projectionnormal, brush->planes[2].normal);
+                               CrossProduct(projectionedge1, projectionnormal, brush->planes[3].normal);
+                               CrossProduct(projectionedge2, projectionnormal, brush->planes[4].normal);
+                       }
+#else
                        CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
                        CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
                        CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
+#endif
                        VectorNormalize(brush->planes[2].normal);
                        VectorNormalize(brush->planes[3].normal);
                        VectorNormalize(brush->planes[4].normal);
@@ -569,15 +406,19 @@ void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
                        if (developer.integer)
                        {
                                // validation code
-                               //VectorSubtract(brush->points[0].v, brush->points[1].v, edge0);
-                               //VectorSubtract(brush->points[2].v, brush->points[1].v, edge1);
-                               CrossProduct(edge1, edge0, normal);
+#if 0
+                               float temp[3];
+
+                               VectorSubtract(brush->points[0].v, brush->points[1].v, edge0);
+                               VectorSubtract(brush->points[2].v, brush->points[1].v, edge1);
+                               CrossProduct(edge0, edge1, normal);
                                VectorNormalize(normal);
                                VectorSubtract(normal, brush->planes[0].normal, temp);
                                if (VectorLength(temp) > 0.01f)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: TriangleNormal gave wrong answer (%f %f %f != correct answer %f %f %f)\n", brush->planes->normal[0], brush->planes->normal[1], brush->planes->normal[2], normal[0], normal[1], normal[2]);
                                if (fabs(DotProduct(brush->planes[1].normal, brush->planes[0].normal) - -1.0f) > 0.01f || fabs(brush->planes[1].dist - -brush->planes[0].dist) > 0.01f)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 1 (%f %f %f %f) is not opposite plane 0 (%f %f %f %f)\n", brush->planes[1].normal[0], brush->planes[1].normal[1], brush->planes[1].normal[2], brush->planes[1].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[0].dist);
+#if 0
                                if (fabs(DotProduct(brush->planes[2].normal, brush->planes[0].normal)) > 0.01f)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 2 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[2].dist);
                                if (fabs(DotProduct(brush->planes[3].normal, brush->planes[0].normal)) > 0.01f)
@@ -590,6 +431,8 @@ void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 3 (%f %f %f %f) is not perpendicular to edge 1 (%f %f %f to %f %f %f)\n", brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist, brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2]);
                                if (fabs(DotProduct(brush->planes[4].normal, edge2)) > 0.01f)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 4 (%f %f %f %f) is not perpendicular to edge 2 (%f %f %f to %f %f %f)\n", brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist, brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2]);
+#endif
+#endif
                                if (fabs(DotProduct(brush->points[0].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[0].normal) - brush->planes[0].dist) > 0.01f)
                                        Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edges (%f %f %f to %f %f %f to %f %f %f) off front plane 0 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[0].dist);
                                if (fabs(DotProduct(brush->points[0].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[1].normal) - brush->planes[1].dist) > 0.01f)
@@ -662,27 +505,26 @@ void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
 colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents)
 {
        colbrushf_t *brush;
-       brush = Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2));
+       brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2));
        brush->supercontents = supercontents;
        brush->numpoints = numpoints;
        brush->numplanes = numpoints + 2;
-       brush->planes = (void *)(brush + 1);
+       brush->planes = (colplanef_t *)(brush + 1);
        brush->points = (colpointf_t *)points;
-       Host_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...\n");
+       Sys_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...\n");
        return brush;
 }
 
-#define COLLISIONEPSILON (1.0f / 32.0f)
-#define COLLISIONEPSILON2 0//(1.0f / 32.0f)
-
 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 {
        int nplane, nplane2, fstartsolid, fendsolid, brushsolid;
-       float enterfrac, leavefrac, d1, d2, f, newimpactnormal[3];
+       float enterfrac, leavefrac, d1, d2, f, imove, newimpactnormal[3], enterfrac2;
        const colplanef_t *startplane, *endplane;
 
+       VectorClear(newimpactnormal);
        enterfrac = -1;
+       enterfrac2 = -1;
        leavefrac = 1;
        fstartsolid = true;
        fendsolid = true;
@@ -700,15 +542,15 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                // any brush with degenerate planes is not worth handling
                                if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
                                {
-                                       Con_Printf("Collision_TraceBrushBrushFloat: degenerate thisbrush plane!\n");
+                                       Con_Print("Collision_TraceBrushBrushFloat: degenerate thisbrush plane!\n");
                                        return;
                                }
                                f = furthestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints);
-                               if (fabs(f - startplane->dist) > 0.01f)
+                               if (fabs(f - startplane->dist) > 0.125f)
                                        Con_Printf("startplane->dist %f != calculated %f (thisbrush_start)\n", startplane->dist, f);
                        }
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints) - COLLISIONEPSILON2;
+                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints) - collision_startnudge.value;
+                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints) - collision_endnudge.value;
                }
                else
                {
@@ -719,49 +561,50 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                // any brush with degenerate planes is not worth handling
                                if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
                                {
-                                       Con_Printf("Collision_TraceBrushBrushFloat: degenerate thatbrush plane!\n");
+                                       Con_Print("Collision_TraceBrushBrushFloat: degenerate thatbrush plane!\n");
                                        return;
                                }
                                f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                               if (fabs(f - startplane->dist) > 0.01f)
+                               if (fabs(f - startplane->dist) > 0.125f)
                                        Con_Printf("startplane->dist %f != calculated %f (thatbrush_start)\n", startplane->dist, f);
                        }
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - startplane->dist;
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - startplane->dist - COLLISIONEPSILON2;
+                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - startplane->dist - collision_startnudge.value;
+                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - endplane->dist - collision_endnudge.value;
                }
                //Con_Printf("%c%i: d1 = %f, d2 = %f, d1 / (d1 - d2) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, d1, d2, d1 / (d1 - d2));
 
-               f = d1 - d2;
-               if (f >= 0)
+               if(d1 > d2)
                {
                        // moving into brush
-                       if (d2 > 0)
+                       if(d2 > 0)
                                return;
-                       if (d1 < 0)
-                               continue;
-                       // enter
-                       fstartsolid = false;
-                       f = (d1 - COLLISIONEPSILON) / f;
-                       f = bound(0, f, 1);
-                       if (enterfrac < f)
+                       if(d1 > 0)
                        {
-                               enterfrac = f;
-                               VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                               // enter
+                               fstartsolid = false;
+                               imove = 1 / (d1 - d2);
+                               f = (d1 - collision_enternudge.value) * imove;
+                               if (enterfrac < f)
+                               {
+                                       enterfrac = f;
+                                       enterfrac2 = f - collision_impactnudge.value * imove;
+                                       VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                               }
                        }
                }
                else
                {
                        // moving out of brush
-                       if (d1 > 0)
+                       if(d1 > 0)
                                return;
-                       if (d2 < 0)
-                               continue;
-                       // leave
-                       fendsolid = false;
-                       f = (d1 + COLLISIONEPSILON) / f;
-                       f = bound(0, f, 1);
-                       if (leavefrac > f)
-                               leavefrac = f;
+                       if(d2 > 0)
+                       {
+                               // leave
+                               fendsolid = false;
+                               f = (d1 + collision_leavenudge.value) / (d1 - d2);
+                               if (leavefrac > f)
+                                       leavefrac = f;
+                       }
                }
        }
 
@@ -781,10 +624,35 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
        // penetrating line segment is normally zero length if this brush was
        // generated from a polygon (infinitely thin), and could even be slightly
        // positive or negative due to rounding errors in that case.
-       if (brushsolid && enterfrac > -1 && enterfrac < trace->fraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
+       if (brushsolid && enterfrac > -1 && enterfrac < trace->realfraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
        {
-               trace->fraction = bound(0, enterfrac, 1);
-               VectorCopy(newimpactnormal, trace->plane.normal);
+#if 0
+               // broken
+               if (thatbrush_start->ispolygon)
+               {
+                       d1 = nearestplanedist_float(thatbrush_start->planes[0].normal, thisbrush_start->points, thisbrush_start->numpoints) - thatbrush_start->planes[0].dist - collision_startnudge.value;
+                       d2 = nearestplanedist_float(thatbrush_end->planes[0].normal, thisbrush_end->points, thisbrush_end->numpoints) - thatbrush_end->planes[0].dist - collision_endnudge.value;
+                       move = d1 - d2;
+                       if (move <= 0 || d2 > collision_enternudge.value || d1 < 0)
+                               return;
+                       // enter
+                       imove = 1 / move;
+                       enterfrac = (d1 - collision_enternudge.value) * imove;
+                       if (enterfrac < trace->realfraction)
+                       {
+                               enterfrac2 = enterfrac - collision_impactnudge.value * imove;
+                               trace->realfraction = bound(0, enterfrac, 1);
+                               trace->fraction = bound(0, enterfrac2, 1);
+                               VectorLerp(thatbrush_start->planes[0].normal, enterfrac, thatbrush_end->planes[0].normal, trace->plane.normal);
+                       }
+               }
+               else
+#endif
+               {
+                       trace->realfraction = bound(0, enterfrac, 1);
+                       trace->fraction = bound(0, enterfrac2, 1);
+                       VectorCopy(newimpactnormal, trace->plane.normal);
+               }
        }
 }
 
@@ -792,10 +660,12 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 {
        int nplane, fstartsolid, fendsolid, brushsolid;
-       float enterfrac, leavefrac, d1, d2, f, newimpactnormal[3];
+       float enterfrac, leavefrac, d1, d2, f, imove, newimpactnormal[3], enterfrac2;
        const colplanef_t *startplane, *endplane;
 
+       VectorClear(newimpactnormal);
        enterfrac = -1;
+       enterfrac2 = -1;
        leavefrac = 1;
        fstartsolid = true;
        fendsolid = true;
@@ -804,37 +674,41 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
        {
                startplane = thatbrush_start->planes + nplane;
                endplane = thatbrush_end->planes + nplane;
-               d1 = DotProduct(startplane->normal, linestart) - startplane->dist;
-               d2 = DotProduct(endplane->normal, lineend) - endplane->dist - COLLISIONEPSILON2;
+               d1 = DotProduct(startplane->normal, linestart) - startplane->dist - collision_startnudge.value;
+               d2 = DotProduct(endplane->normal, lineend) - endplane->dist - collision_endnudge.value;
                if (developer.integer)
                {
                        // any brush with degenerate planes is not worth handling
                        if (DotProduct(startplane->normal, startplane->normal) < 0.9f || DotProduct(endplane->normal, endplane->normal) < 0.9f)
                        {
-                               Con_Printf("Collision_TraceLineBrushFloat: degenerate plane!\n");
+                               Con_Print("Collision_TraceLineBrushFloat: degenerate plane!\n");
                                return;
                        }
-                       f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                       if (fabs(f - startplane->dist) > 0.01f)
-                               Con_Printf("startplane->dist %f != calculated %f\n", startplane->dist, f);
+                       if (thatbrush_start->numpoints)
+                       {
+                               f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
+                               if (fabs(f - startplane->dist) > 0.125f)
+                                       Con_Printf("startplane->dist %f != calculated %f\n", startplane->dist, f);
+                       }
                }
 
-               f = d1 - d2;
-               if (f >= 0)
+               if (d1 > d2)
                {
                        // moving into brush
                        if (d2 > 0)
                                return;
-                       if (d1 < 0)
-                               continue;
-                       // enter
-                       fstartsolid = false;
-                       f = (d1 - COLLISIONEPSILON) / f;
-                       f = bound(0, f, 1);
-                       if (enterfrac < f)
+                       if (d1 > 0)
                        {
-                               enterfrac = f;
-                               VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                               // enter
+                               fstartsolid = false;
+                               imove = 1 / (d1 - d2);
+                               f = (d1 - collision_enternudge.value) * imove;
+                               if (enterfrac < f)
+                               {
+                                       enterfrac = f;
+                                       enterfrac2 = f - collision_impactnudge.value * imove;
+                                       VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                               }
                        }
                }
                else
@@ -842,14 +716,14 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
                        // moving out of brush
                        if (d1 > 0)
                                return;
-                       if (d2 < 0)
-                               continue;
-                       // leave
-                       fendsolid = false;
-                       f = (d1 + COLLISIONEPSILON) / f;
-                       f = bound(0, f, 1);
-                       if (leavefrac > f)
-                               leavefrac = f;
+                       if (d2 > 0)
+                       {
+                               // leave
+                               fendsolid = false;
+                               f = (d1 + collision_leavenudge.value) / (d1 - d2);
+                               if (leavefrac > f)
+                                       leavefrac = f;
+                       }
                }
        }
 
@@ -869,10 +743,52 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
        // penetrating line segment is normally zero length if this brush was
        // generated from a polygon (infinitely thin), and could even be slightly
        // positive or negative due to rounding errors in that case.
-       if (brushsolid && enterfrac > -1 && enterfrac < trace->fraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
+       if (brushsolid && enterfrac > -1 && enterfrac < trace->realfraction && enterfrac - (1.0f / 1024.0f) <= leavefrac)
        {
-               trace->fraction = bound(0, enterfrac, 1);
-               VectorCopy(newimpactnormal, trace->plane.normal);
+#if 0
+               // broken
+               if (thatbrush_start->ispolygon)
+               {
+                       d1 = DotProduct(thatbrush_start->planes[0].normal, linestart) - thatbrush_start->planes[0].dist - collision_startnudge.value;
+                       d2 = DotProduct(thatbrush_end->planes[0].normal, lineend) - thatbrush_end->planes[0].dist - collision_endnudge.value;
+                       move = d1 - d2;
+                       if (move <= 0 || d2 > collision_enternudge.value || d1 < 0)
+                               return;
+                       // enter
+                       imove = 1 / move;
+                       enterfrac = (d1 - collision_enternudge.value) * imove;
+                       if (enterfrac < trace->realfraction)
+                       {
+                               enterfrac2 = enterfrac - collision_impactnudge.value * imove;
+                               trace->realfraction = bound(0, enterfrac, 1);
+                               trace->fraction = bound(0, enterfrac2, 1);
+                               VectorLerp(thatbrush_start->planes[0].normal, enterfrac, thatbrush_end->planes[0].normal, trace->plane.normal);
+                       }
+               }
+               else
+#endif
+               {
+                       trace->realfraction = bound(0, enterfrac, 1);
+                       trace->fraction = bound(0, enterfrac2, 1);
+                       VectorCopy(newimpactnormal, trace->plane.normal);
+               }
+       }
+}
+
+void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
+{
+       int nplane;
+       const colplanef_t *plane;
+
+       for (nplane = 0, plane = thatbrush->planes;nplane < thatbrush->numplanes;nplane++, plane++)
+               if (DotProduct(plane->normal, point) > plane->dist)
+                       return;
+
+       trace->startsupercontents |= thatbrush->supercontents;
+       if (trace->hitsupercontentsmask & thatbrush->supercontents)
+       {
+               trace->startsolid = true;
+               trace->allsolid = true;
        }
 }
 
@@ -880,18 +796,30 @@ static colpointf_t polyf_points[256];
 static colplanef_t polyf_planes[256 + 2];
 static colbrushf_t polyf_brush;
 
+void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
+{
+       while (numpoints--)
+       {
+               out->v[0] = floor(in->v[0] * fractionprecision + 0.5f) * invfractionprecision;
+               out->v[1] = floor(in->v[1] * fractionprecision + 0.5f) * invfractionprecision;
+               out->v[2] = floor(in->v[2] * fractionprecision + 0.5f) * invfractionprecision;
+       }
+}
+
 void Collision_TraceBrushPolygonFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numpoints, const float *points, int supercontents)
 {
        if (numpoints > 256)
        {
-               Con_Printf("Polygon with more than 256 points not supported yet (fixme!)\n");
+               Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
                return;
        }
        polyf_brush.numpoints = numpoints;
        polyf_brush.numplanes = numpoints + 2;
-       polyf_brush.points = (colpointf_t *)points;
+       //polyf_brush.points = (colpointf_t *)points;
        polyf_brush.planes = polyf_planes;
        polyf_brush.supercontents = supercontents;
+       polyf_brush.points = polyf_points;
+       Collision_SnapCopyPoints(numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
        //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
        Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brush, &polyf_brush);
@@ -911,12 +839,13 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
                VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
                VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
                VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
-               facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0]));
-               facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1]));
-               facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2]));
-               facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0]));
-               facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1]));
-               facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2]));
+               Collision_SnapCopyPoints(3, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+               facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0])) - 1;
+               facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1])) - 1;
+               facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2])) - 1;
+               facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0])) + 1;
+               facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1])) + 1;
+               facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2])) + 1;
                if (BoxesOverlap(segmentmins, segmentmaxs, facemins, facemaxs))
                {
                        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
@@ -930,12 +859,14 @@ void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, con
 {
        if (numpoints > 256)
        {
-               Con_Printf("Polygon with more than 256 points not supported yet (fixme!)\n");
+               Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
                return;
        }
        polyf_brush.numpoints = numpoints;
        polyf_brush.numplanes = numpoints + 2;
-       polyf_brush.points = (colpointf_t *)points;
+       //polyf_brush.points = (colpointf_t *)points;
+       polyf_brush.points = polyf_points;
+       Collision_SnapCopyPoints(numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
        polyf_brush.planes = polyf_planes;
        polyf_brush.supercontents = supercontents;
        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
@@ -946,7 +877,11 @@ void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, con
 void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numtriangles, const int *element3i, const float *vertex3f, int supercontents, const vec3_t segmentmins, const vec3_t segmentmaxs)
 {
        int i;
-       float facemins[3], facemaxs[3];
+#if 1
+       // FIXME: snap vertices?
+       for (i = 0;i < numtriangles;i++, element3i += 3)
+               Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3);
+#else
        polyf_brush.numpoints = 3;
        polyf_brush.numplanes = 5;
        polyf_brush.points = polyf_points;
@@ -954,15 +889,17 @@ void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart
        polyf_brush.supercontents = supercontents;
        for (i = 0;i < numtriangles;i++, element3i += 3)
        {
+               float facemins[3], facemaxs[3];
                VectorCopy(vertex3f + element3i[0] * 3, polyf_points[0].v);
                VectorCopy(vertex3f + element3i[1] * 3, polyf_points[1].v);
                VectorCopy(vertex3f + element3i[2] * 3, polyf_points[2].v);
-               facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0]));
-               facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1]));
-               facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2]));
-               facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0]));
-               facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1]));
-               facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2]));
+               Collision_SnapCopyPoints(numpoints, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+               facemins[0] = min(polyf_points[0].v[0], min(polyf_points[1].v[0], polyf_points[2].v[0])) - 1;
+               facemins[1] = min(polyf_points[0].v[1], min(polyf_points[1].v[1], polyf_points[2].v[1])) - 1;
+               facemins[2] = min(polyf_points[0].v[2], min(polyf_points[1].v[2], polyf_points[2].v[2])) - 1;
+               facemaxs[0] = max(polyf_points[0].v[0], max(polyf_points[1].v[0], polyf_points[2].v[0])) + 1;
+               facemaxs[1] = max(polyf_points[0].v[1], max(polyf_points[1].v[1], polyf_points[2].v[1])) + 1;
+               facemaxs[2] = max(polyf_points[0].v[2], max(polyf_points[1].v[2], polyf_points[2].v[2])) + 1;
                if (BoxesOverlap(segmentmins, segmentmaxs, facemins, facemaxs))
                {
                        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
@@ -970,6 +907,7 @@ void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart
                        Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
                }
        }
+#endif
 }
 
 
@@ -982,7 +920,7 @@ void Collision_TraceBrushPolygonTransformFloat(trace_t *trace, const colbrushf_t
        int i;
        if (numpoints > 256)
        {
-               Con_Printf("Polygon with more than 256 points not supported yet (fixme!)\n");
+               Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
                return;
        }
        polyf_brushstart.numpoints = numpoints;
@@ -999,6 +937,8 @@ void Collision_TraceBrushPolygonTransformFloat(trace_t *trace, const colbrushf_t
        polyf_brushend.supercontents = supercontents;
        for (i = 0;i < numpoints;i++)
                Matrix4x4_Transform(polygonmatrixend, points + i * 3, polyf_brushend.points[i].v);
+       Collision_SnapCopyPoints(numpoints, polyf_pointsstart, polyf_pointsstart, COLLISION_SNAPSCALE, COLLISION_SNAP);
+       Collision_SnapCopyPoints(numpoints, polyf_pointsend, polyf_pointsend, COLLISION_SNAPSCALE, COLLISION_SNAP);
        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushstart);
        Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushend);
 
@@ -1037,11 +977,12 @@ void Collision_InitBrushForBox(void)
 
 colbrushf_t *Collision_BrushForBox(const matrix4x4_t *matrix, const vec3_t mins, const vec3_t maxs)
 {
-       int i;
+       int i, j;
        vec3_t v;
        colbrushf_t *brush;
        if (brushforbox_brush[0].numpoints == 0)
                Collision_InitBrushForBox();
+       // FIXME: these probably don't actually need to be normalized if the collision code does not care
        if (VectorCompare(mins, maxs))
        {
                // point brush
@@ -1066,9 +1007,27 @@ colbrushf_t *Collision_BrushForBox(const matrix4x4_t *matrix, const vec3_t mins,
                        v[i >> 1] = i & 1 ? 1 : -1;
                        Matrix4x4_Transform3x3(matrix, v, brush->planes[i].normal);
                        VectorNormalize(brush->planes[i].normal);
-                       brush->planes[i].dist = furthestplanedist_float(brush->planes[i].normal, brush->points, brush->numpoints);
                }
        }
+       for (j = 0;j < brush->numplanes;j++)
+               brush->planes[j].dist = furthestplanedist_float(brush->planes[j].normal, brush->points, brush->numpoints);
+       VectorCopy(brush->points[0].v, brush->mins);
+       VectorCopy(brush->points[0].v, brush->maxs);
+       for (j = 1;j < brush->numpoints;j++)
+       {
+               brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
+               brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
+               brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
+               brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
+               brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
+               brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
+       }
+       brush->mins[0] -= 1;
+       brush->mins[1] -= 1;
+       brush->mins[2] -= 1;
+       brush->maxs[0] += 1;
+       brush->maxs[1] += 1;
+       brush->maxs[2] += 1;
        Collision_ValidateBrush(brush);
        return brush;
 }
@@ -1092,11 +1051,15 @@ void Collision_ClipTrace_BrushBox(trace_t *trace, const vec3_t cmins, const vec3
        memset(trace, 0, sizeof(trace_t));
        trace->hitsupercontentsmask = hitsupercontentsmask;
        trace->fraction = 1;
+       trace->realfraction = 1;
        trace->allsolid = true;
        Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, boxbrush, boxbrush);
 }
 
-// LordHavoc: currently unused and not yet tested
+//pseudocode for detecting line/sphere overlap without calculating an impact point
+//linesphereorigin = sphereorigin - linestart;linediff = lineend - linestart;linespherefrac = DotProduct(linesphereorigin, linediff) / DotProduct(linediff, linediff);return VectorLength2(linesphereorigin - bound(0, linespherefrac, 1) * linediff) >= sphereradius*sphereradius;
+
+// LordHavoc: currently unused, but tested
 // note: this can be used for tracing a moving sphere vs a stationary sphere,
 // by simply adding the moving sphere's radius to the sphereradius parameter,
 // all the results are correct (impactpoint, impactnormal, and fraction)
@@ -1105,66 +1068,253 @@ float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double
        double dir[3], scale, v[3], deviationdist, impactdist, linelength;
        // make sure the impactpoint and impactnormal are valid even if there is
        // no collision
-       impactpoint[0] = lineend[0];
-       impactpoint[1] = lineend[1];
-       impactpoint[2] = lineend[2];
-       impactnormal[0] = 0;
-       impactnormal[1] = 0;
-       impactnormal[2] = 0;
+       VectorCopy(lineend, impactpoint);
+       VectorClear(impactnormal);
        // calculate line direction
-       dir[0] = lineend[0] - linestart[0];
-       dir[1] = lineend[1] - linestart[1];
-       dir[2] = lineend[2] - linestart[2];
+       VectorSubtract(lineend, linestart, dir);
        // normalize direction
-       linelength = sqrt(dir[0] * dir[0] + dir[1] * dir[1] + dir[2] * dir[2]);
+       linelength = VectorLength(dir);
        if (linelength)
        {
                scale = 1.0 / linelength;
-               dir[0] *= scale;
-               dir[1] *= scale;
-               dir[2] *= scale;
+               VectorScale(dir, scale, dir);
        }
        // this dotproduct calculates the distance along the line at which the
        // sphere origin is (nearest point to the sphere origin on the line)
-       impactdist = dir[0] * (sphereorigin[0] - linestart[0]) + dir[1] * (sphereorigin[1] - linestart[1]) + dir[2] * (sphereorigin[2] - linestart[2]);
+       impactdist = DotProduct(sphereorigin, dir) - DotProduct(linestart, dir);
        // calculate point on line at that distance, and subtract the
        // sphereorigin from it, so we have a vector to measure for the distance
        // of the line from the sphereorigin (deviation, how off-center it is)
-       v[0] = linestart[0] + impactdist * dir[0] - sphereorigin[0];
-       v[1] = linestart[1] + impactdist * dir[1] - sphereorigin[1];
-       v[2] = linestart[2] + impactdist * dir[2] - sphereorigin[2];
-       deviationdist = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
+       VectorMA(linestart, impactdist, dir, v);
+       VectorSubtract(v, sphereorigin, v);
+       deviationdist = VectorLength2(v);
        // if outside the radius, it's a miss for sure
        // (we do this comparison using squared radius to avoid a sqrt)
        if (deviationdist > sphereradius*sphereradius)
                return 1; // miss (off to the side)
        // nudge back to find the correct impact distance
-       impactdist += (sqrt(deviationdist) - sphereradius);
+       impactdist += deviationdist - sphereradius;
        if (impactdist >= linelength)
                return 1; // miss (not close enough)
        if (impactdist < 0)
                return 1; // miss (linestart is past or inside sphere)
        // calculate new impactpoint
-       impactpoint[0] = linestart[0] + impactdist * dir[0];
-       impactpoint[1] = linestart[1] + impactdist * dir[1];
-       impactpoint[2] = linestart[2] + impactdist * dir[2];
+       VectorMA(linestart, impactdist, dir, impactpoint);
        // calculate impactnormal (surface normal at point of impact)
-       impactnormal[0] = impactpoint[0] - sphereorigin[0];
-       impactnormal[1] = impactpoint[1] - sphereorigin[1];
-       impactnormal[2] = impactpoint[2] - sphereorigin[2];
+       VectorSubtract(impactpoint, sphereorigin, impactnormal);
        // normalize impactnormal
-       scale = impactnormal[0] * impactnormal[0] + impactnormal[1] * impactnormal[1] + impactnormal[2] * impactnormal[2];
-       if (scale)
-       {
-               scale = 1.0 / sqrt(scale);
-               impactnormal[0] *= scale;
-               impactnormal[1] *= scale;
-               impactnormal[2] *= scale;
-       }
+       VectorNormalize(impactnormal);
        // return fraction of movement distance
        return impactdist / linelength;
 }
 
+void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const float *point0, const float *point1, const float *point2)
+{
+#if 1
+       // more optimized
+       float d1, d2, d, f, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
+
+       // this function executes:
+       // 32 ops when line starts behind triangle
+       // 38 ops when line ends infront of triangle
+       // 43 ops when line fraction is already closer than this triangle
+       // 72 ops when line is outside edge 01
+       // 92 ops when line is outside edge 21
+       // 115 ops when line is outside edge 02
+       // 123 ops when line impacts triangle and updates trace results
+
+       // this code is designed for clockwise triangles, conversion to
+       // counterclockwise would require swapping some things around...
+       // it is easier to simply swap the point0 and point2 parameters to this
+       // function when calling it than it is to rewire the internals.
+
+       // calculate the faceplanenormal of the triangle, this represents the front side
+       // 15 ops
+       VectorSubtract(point0, point1, edge01);
+       VectorSubtract(point2, point1, edge21);
+       CrossProduct(edge01, edge21, faceplanenormal);
+       // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
+       // 6 ops
+       faceplanenormallength2 = DotProduct(faceplanenormal, faceplanenormal);
+       if (faceplanenormallength2 < 0.0001f)
+               return;
+       // calculate the distance
+       // 5 ops
+       faceplanedist = DotProduct(point0, faceplanenormal);
+
+       // if start point is on the back side there is no collision
+       // (we don't care about traces going through the triangle the wrong way)
+
+       // calculate the start distance
+       // 6 ops
+       d1 = DotProduct(faceplanenormal, linestart);
+       if (d1 <= faceplanedist)
+               return;
+
+       // calculate the end distance
+       // 6 ops
+       d2 = DotProduct(faceplanenormal, lineend);
+       // if both are in front, there is no collision
+       if (d2 >= faceplanedist)
+               return;
+
+       // from here on we know d1 is >= 0 and d2 is < 0
+       // this means the line starts infront and ends behind, passing through it
+
+       // calculate the recipricol of the distance delta,
+       // so we can use it multiple times cheaply (instead of division)
+       // 2 ops
+       d = 1.0f / (d1 - d2);
+       // calculate the impact fraction by taking the start distance (> 0)
+       // and subtracting the face plane distance (this is the distance of the
+       // triangle along that same normal)
+       // then multiply by the recipricol distance delta
+       // 2 ops
+       f = (d1 - faceplanedist) * d;
+       // skip out if this impact is further away than previous ones
+       // 1 ops
+       if (f > trace->realfraction)
+               return;
+       // calculate the perfect impact point for classification of insidedness
+       // 9 ops
+       impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
+       impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
+       impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
+
+       // calculate the edge normal and reject if impact is outside triangle
+       // (an edge normal faces away from the triangle, to get the desired normal
+       //  a crossproduct with the faceplanenormal is used, and because of the way
+       // the insidedness comparison is written it does not need to be normalized)
+
+       // first use the two edges from the triangle plane math
+       // the other edge only gets calculated if the point survives that long
+
+       // 20 ops
+       CrossProduct(edge01, faceplanenormal, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
+               return;
+
+       // 20 ops
+       CrossProduct(faceplanenormal, edge21, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
+               return;
+
+       // 23 ops
+       VectorSubtract(point0, point2, edge02);
+       CrossProduct(faceplanenormal, edge02, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
+               return;
+
+       // 8 ops (rare)
+
+       // store the new trace fraction
+       trace->realfraction = f;
+
+       // calculate a nudged fraction to keep it out of the surface
+       // (the main fraction remains perfect)
+       trace->fraction = f - collision_impactnudge.value * d;
+
+       // store the new trace plane (because collisions only happen from
+       // the front this is always simply the triangle normal, never flipped)
+       d = 1.0 / sqrt(faceplanenormallength2);
+       VectorScale(faceplanenormal, d, trace->plane.normal);
+       trace->plane.dist = faceplanedist * d;
+#else
+       float d1, d2, d, f, fnudged, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, edge[3];
+
+       // this code is designed for clockwise triangles, conversion to
+       // counterclockwise would require swapping some things around...
+       // it is easier to simply swap the point0 and point2 parameters to this
+       // function when calling it than it is to rewire the internals.
+
+       // calculate the unnormalized faceplanenormal of the triangle,
+       // this represents the front side
+       TriangleNormal(point0, point1, point2, faceplanenormal);
+       // there's no point in processing a degenerate triangle
+       // (GIGO - Garbage In, Garbage Out)
+       if (DotProduct(faceplanenormal, faceplanenormal) < 0.0001f)
+               return;
+       // calculate the unnormalized distance
+       faceplanedist = DotProduct(point0, faceplanenormal);
+
+       // calculate the unnormalized start distance
+       d1 = DotProduct(faceplanenormal, linestart) - faceplanedist;
+       // if start point is on the back side there is no collision
+       // (we don't care about traces going through the triangle the wrong way)
+       if (d1 <= 0)
+               return;
+
+       // calculate the unnormalized end distance
+       d2 = DotProduct(faceplanenormal, lineend) - faceplanedist;
+       // if both are in front, there is no collision
+       if (d2 >= 0)
+               return;
+
+       // from here on we know d1 is >= 0 and d2 is < 0
+       // this means the line starts infront and ends behind, passing through it
+
+       // calculate the recipricol of the distance delta,
+       // so we can use it multiple times cheaply (instead of division)
+       d = 1.0f / (d1 - d2);
+       // calculate the impact fraction by taking the start distance (> 0)
+       // and subtracting the face plane distance (this is the distance of the
+       // triangle along that same normal)
+       // then multiply by the recipricol distance delta
+       f = d1 * d;
+       // skip out if this impact is further away than previous ones
+       if (f > trace->realfraction)
+               return;
+       // calculate the perfect impact point for classification of insidedness
+       impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
+       impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
+       impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
+
+       // calculate the edge normal and reject if impact is outside triangle
+       // (an edge normal faces away from the triangle, to get the desired normal
+       //  a crossproduct with the faceplanenormal is used, and because of the way
+       // the insidedness comparison is written it does not need to be normalized)
+
+       VectorSubtract(point2, point0, edge);
+       CrossProduct(edge, faceplanenormal, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
+               return;
+
+       VectorSubtract(point0, point1, edge);
+       CrossProduct(edge, faceplanenormal, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
+               return;
+
+       VectorSubtract(point1, point2, edge);
+       CrossProduct(edge, faceplanenormal, edgenormal);
+       if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
+               return;
+
+       // store the new trace fraction
+       trace->realfraction = bound(0, f, 1);
+
+       // store the new trace plane (because collisions only happen from
+       // the front this is always simply the triangle normal, never flipped)
+       VectorNormalize(faceplanenormal);
+       VectorCopy(faceplanenormal, trace->plane.normal);
+       trace->plane.dist = DotProduct(point0, faceplanenormal);
+
+       // calculate the normalized start and end distances
+       d1 = DotProduct(trace->plane.normal, linestart) - trace->plane.dist;
+       d2 = DotProduct(trace->plane.normal, lineend) - trace->plane.dist;
+
+       // calculate a nudged fraction to keep it out of the surface
+       // (the main fraction remains perfect)
+       fnudged = (d1 - collision_impactnudge.value) / (d1 - d2);
+       trace->fraction = bound(0, fnudged, 1);
+
+       // store the new trace endpos
+       // not needed, it's calculated later when the trace is finished
+       //trace->endpos[0] = linestart[0] + fnudged * (lineend[0] - linestart[0]);
+       //trace->endpos[1] = linestart[1] + fnudged * (lineend[1] - linestart[1]);
+       //trace->endpos[2] = linestart[2] + fnudged * (lineend[2] - linestart[2]);
+#endif
+}
+
 typedef struct colbspnode_s
 {
        mplane_t plane;
@@ -1189,9 +1339,9 @@ colbsp_t;
 colbsp_t *Collision_CreateCollisionBSP(mempool_t *mempool)
 {
        colbsp_t *bsp;
-       bsp = Mem_Alloc(mempool, sizeof(colbsp_t));
+       bsp = (colbsp_t *)Mem_Alloc(mempool, sizeof(colbsp_t));
        bsp->mempool = mempool;
-       bsp->nodes = Mem_Alloc(bsp->mempool, sizeof(colbspnode_t));
+       bsp->nodes = (colbspnode_t *)Mem_Alloc(bsp->mempool, sizeof(colbspnode_t));
        return bsp;
 }
 
@@ -1232,5 +1382,11 @@ void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const co
                maxs[1] = min(maxs[1], min(tempstart[1], tempend[1]));
                maxs[2] = min(maxs[2], min(tempstart[2], tempend[2]));
        }
+       mins[0] -= 1;
+       mins[1] -= 1;
+       mins[2] -= 1;
+       maxs[0] += 1;
+       maxs[1] += 1;
+       maxs[2] += 1;
 }