Fix setinfo.
[xonotic/darkplaces.git] / collision.c
index b6bdc44..1eee2c2 100644 (file)
@@ -1,27 +1,40 @@
 
 #include "quakedef.h"
 #include "polygon.h"
+#include "collision.h"
 
+#define COLLISION_EDGEDIR_DOT_EPSILON (0.999f)
+#define COLLISION_EDGECROSS_MINLENGTH2 (1.0f / 4194304.0f)
 #define COLLISION_SNAPSCALE (32.0f)
 #define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
 #define COLLISION_SNAP2 (2.0f / COLLISION_SNAPSCALE)
 #define COLLISION_PLANE_DIST_EPSILON (2.0f / COLLISION_SNAPSCALE)
 
 cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125", "how much to back off from the impact"};
-cvar_t collision_startnudge = {0, "collision_startnudge", "0", "how much to bias collision trace start"};
-cvar_t collision_endnudge = {0, "collision_endnudge", "0", "how much to bias collision trace end"};
-cvar_t collision_enternudge = {0, "collision_enternudge", "0", "how much to bias collision entry fraction"};
-cvar_t collision_leavenudge = {0, "collision_leavenudge", "0", "how much to bias collision exit fraction"};
-cvar_t collision_prefernudgedfraction = {0, "collision_prefernudgedfraction", "1", "whether to sort collision events by nudged fraction (1) or real fraction (0)"};
+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)"};
+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)"};
+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)"};
+cvar_t collision_debug_tracelineasbox = {0, "collision_debug_tracelineasbox", "0", "workaround for any bugs in Collision_TraceLineBrushFloat by using Collision_TraceBrushBrushFloat"};
+cvar_t collision_cache = {0, "collision_cache", "1", "store results of collision traces for next frame to reuse if possible (optimization)"};
+cvar_t collision_triangle_bevelsides = {0, "collision_triangle_bevelsides", "0", "generate sloped edge planes on triangles - if 0, see axialedgeplanes"};
+cvar_t collision_triangle_axialsides = {0, "collision_triangle_axialsides", "1", "generate axially-aligned edge planes on triangles - otherwise use perpendicular edge planes"};
+cvar_t collision_bih_fullrecursion = { 0, "collision_bih_fullrecursion", "0", "debugging option to disable the bih recursion optimizations by iterating the entire tree" };
+
+mempool_t *collision_mempool;
 
 void Collision_Init (void)
 {
        Cvar_RegisterVariable(&collision_impactnudge);
-       Cvar_RegisterVariable(&collision_startnudge);
-       Cvar_RegisterVariable(&collision_endnudge);
-       Cvar_RegisterVariable(&collision_enternudge);
-       Cvar_RegisterVariable(&collision_leavenudge);
-       Cvar_RegisterVariable(&collision_prefernudgedfraction);
+       Cvar_RegisterVariable(&collision_extendmovelength);
+       Cvar_RegisterVariable(&collision_extendtracelinelength);
+       Cvar_RegisterVariable(&collision_extendtraceboxlength);
+       Cvar_RegisterVariable(&collision_debug_tracelineasbox);
+       Cvar_RegisterVariable(&collision_cache);
+       Cvar_RegisterVariable(&collision_triangle_bevelsides);
+       Cvar_RegisterVariable(&collision_triangle_axialsides);
+       Cvar_RegisterVariable(&collision_bih_fullrecursion);
+       collision_mempool = Mem_AllocPool("collision cache", 0, NULL);
+       Collision_Cache_Init(collision_mempool);
 }
 
 
@@ -37,7 +50,7 @@ void Collision_Init (void)
 
 
 
-void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
+static void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
 {
        int i;
        Con_Printf("3 %s\n%i\n", name, brush->numpoints);
@@ -49,7 +62,7 @@ void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
                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);
 }
 
-void Collision_ValidateBrush(colbrushf_t *brush)
+static void Collision_ValidateBrush(colbrushf_t *brush)
 {
        int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
        float d;
@@ -108,7 +121,7 @@ void Collision_ValidateBrush(colbrushf_t *brush)
                Collision_PrintBrushAsQHull(brush, "unnamed");
 }
 
-float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
+static float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 {
        float dist, bestdist;
        if (!numpoints)
@@ -124,7 +137,7 @@ float nearestplanedist_float(const float *normal, const colpointf_t *points, int
        return bestdist;
 }
 
-float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
+static float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 {
        float dist, bestdist;
        if (!numpoints)
@@ -140,15 +153,23 @@ float furthestplanedist_float(const float *normal, const colpointf_t *points, in
        return bestdist;
 }
 
+static void Collision_CalcEdgeDirsForPolygonBrushFloat(colbrushf_t *brush)
+{
+       int i, j;
+       for (i = 0, j = brush->numpoints - 1;i < brush->numpoints;j = i, i++)
+               VectorSubtract(brush->points[i].v, brush->points[j].v, brush->edgedirs[j].v);
+}
 
-colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const colplanef_t *originalplanes, int supercontents)
+colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const colplanef_t *originalplanes, int supercontents, int q3surfaceflags, const texture_t *texture, int hasaabbplanes)
 {
        // TODO: planesbuf could be replaced by a remapping table
-       int j, k, m, w, xyzflags;
-       int numpointsbuf = 0, maxpointsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
+       int j, k, w, xyzflags;
+       int numpointsbuf = 0, maxpointsbuf = 256, numedgedirsbuf = 0, maxedgedirsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
+       int isaabb = true;
        double maxdist;
        colbrushf_t *brush;
        colpointf_t pointsbuf[256];
+       colpointf_t edgedirsbuf[256];
        colplanef_t planesbuf[256];
        int elementsbuf[1024];
        int polypointbuf[256];
@@ -156,13 +177,22 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
        int pnumpoints;
        double p[2][3*64];
 #if 0
-       // enable these if debugging to avoid seeing garbage in unused data
+       // enable these if debugging to avoid seeing garbage in unused data-
        memset(pointsbuf, 0, sizeof(pointsbuf));
+       memset(edgedirsbuf, 0, sizeof(edgedirsbuf));
        memset(planesbuf, 0, sizeof(planesbuf));
        memset(elementsbuf, 0, sizeof(elementsbuf));
        memset(polypointbuf, 0, sizeof(polypointbuf));
        memset(p, 0, sizeof(p));
 #endif
+
+       // check if there are too many planes and skip the brush
+       if (numoriginalplanes >= maxplanesbuf)
+       {
+               Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
+               return NULL;
+       }
+
        // figure out how large a bounding box we need to properly compute this brush
        maxdist = 0;
        for (j = 0;j < numoriginalplanes;j++)
@@ -174,20 +204,7 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
        // whose polygon is clipped away by the other planes)
        for (j = 0;j < numoriginalplanes;j++)
        {
-               // add the plane uniquely (no duplicates)
-               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 < numplanesbuf)
-                       continue;
-               // check if there are too many and skip the brush
-               if (numplanesbuf >= maxplanesbuf)
-               {
-                       Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
-                       return NULL;
-               }
-
+               int n;
                // add the new plane
                VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
                planesbuf[numplanesbuf].dist = originalplanes[j].dist;
@@ -250,8 +267,10 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
                        return NULL;
                }
 
+               // add the unique points for this polygon
                for (k = 0;k < pnumpoints;k++)
                {
+                       int m;
                        float v[3];
                        // downgrade to float precision before comparing
                        VectorCopy(&p[w][k*3], v);
@@ -287,6 +306,48 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
                        elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
                        elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
                }
+
+               // add the unique edgedirs for this polygon
+               for (k = 0, n = pnumpoints-1;k < pnumpoints;n = k, k++)
+               {
+                       int m;
+                       float dir[3];
+                       // downgrade to float precision before comparing
+                       VectorSubtract(&p[w][k*3], &p[w][n*3], dir);
+                       VectorNormalize(dir);
+
+                       // check if there is already a matching edgedir (no duplicates)
+                       for (m = 0;m < numedgedirsbuf;m++)
+                               if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
+                                       break;
+                       // skip this if there is
+                       if (m < numedgedirsbuf)
+                               continue;
+
+                       // try again with negated edgedir
+                       VectorNegate(dir, dir);
+                       // check if there is already a matching edgedir (no duplicates)
+                       for (m = 0;m < numedgedirsbuf;m++)
+                               if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
+                                       break;
+                       // if there is no match, add a new one
+                       if (m == numedgedirsbuf)
+                       {
+                               // check if there are too many and skip the brush
+                               if (numedgedirsbuf >= maxedgedirsbuf)
+                               {
+                                       Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many edgedirs for buffer\n");
+                                       return NULL;
+                               }
+                               // add the new one
+                               VectorCopy(dir, edgedirsbuf[numedgedirsbuf].v);
+                               numedgedirsbuf++;
+                       }
+               }
+
+               // if any normal is not purely axial, it's not an axis-aligned box
+               if (isaabb && (originalplanes[j].normal[0] == 0) + (originalplanes[j].normal[1] == 0) + (originalplanes[j].normal[2] == 0) < 2)
+                       isaabb = false;
        }
 
        // if nothing is left, there's nothing to allocate
@@ -309,20 +370,32 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
        }
 
        // allocate the brush and copy to it
-       brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpointsbuf + sizeof(colplanef_t) * numplanesbuf + sizeof(int) * numelementsbuf);
+       brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpointsbuf + sizeof(colpointf_t) * numedgedirsbuf + sizeof(colplanef_t) * numplanesbuf + sizeof(int) * numelementsbuf);
+       brush->isaabb = isaabb;
+       brush->hasaabbplanes = hasaabbplanes;
        brush->supercontents = supercontents;
        brush->numplanes = numplanesbuf;
+       brush->numedgedirs = numedgedirsbuf;
        brush->numpoints = numpointsbuf;
        brush->numtriangles = numelementsbuf / 3;
        brush->planes = (colplanef_t *)(brush + 1);
        brush->points = (colpointf_t *)(brush->planes + brush->numplanes);
+       brush->edgedirs = (colpointf_t *)(brush->points + brush->numpoints);
        brush->elements = (int *)(brush->points + brush->numpoints);
+       brush->q3surfaceflags = q3surfaceflags;
+       brush->texture = texture;
        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->numedgedirs;j++)
+       {
+               brush->edgedirs[j].v[0] = edgedirsbuf[j].v[0];
+               brush->edgedirs[j].v[1] = edgedirsbuf[j].v[1];
+               brush->edgedirs[j].v[2] = edgedirsbuf[j].v[2];
+       }
        for (j = 0;j < brush->numplanes;j++)
        {
                brush->planes[j].normal[0] = planesbuf[j].normal[0];
@@ -375,163 +448,101 @@ colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalpla
 
 
 
-void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
+void Collision_CalcPlanesForTriangleBrushFloat(colbrushf_t *brush)
 {
-       int i;
-       float edge0[3], edge1[3], edge2[3], normal[3], dist, bestdist;
-       colpointf_t *p, *p2;
+       float edge0[3], edge1[3], edge2[3];
+       colpointf_t *p;
 
-       // FIXME: these probably don't actually need to be normalized if the collision code does not care
-       if (brush->numpoints == 3)
+       TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
+       if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
        {
-               // optimized triangle case
-               TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
-               if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
-               {
-                       // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
-                       brush->numplanes = 0;
-                       return;
-               }
-               else
-               {
-                       brush->numplanes = 5;
-                       VectorNormalize(brush->planes[0].normal);
-                       brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
-                       VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
-                       brush->planes[1].dist = -brush->planes[0].dist;
-                       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);
-                       brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
-                       brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
-                       brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
-
-                       if (developer.integer >= 100)
-                       {
-                               // validation code
-#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)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 3 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[3].dist);
-                               if (fabs(DotProduct(brush->planes[4].normal, brush->planes[0].normal)) > 0.01f)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 4 (%f %f %f %f) is not perpendicular to plane 0 (%f %f %f %f)\n", brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist, brush->planes[0].normal[0], brush->planes[0].normal[1], brush->planes[0].normal[2], brush->planes[4].dist);
-                               if (fabs(DotProduct(brush->planes[2].normal, edge0)) > 0.01f)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: plane 2 (%f %f %f %f) is not perpendicular to edge 0 (%f %f %f to %f %f %f)\n", brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist, brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2]);
-                               if (fabs(DotProduct(brush->planes[3].normal, edge1)) > 0.01f)
-                                       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)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edges (%f %f %f to %f %f %f to %f %f %f) off back plane 1 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[1].normal[0], brush->planes[1].normal[1], brush->planes[1].normal[2], brush->planes[1].dist);
-                               if (fabs(DotProduct(brush->points[2].v, brush->planes[2].normal) - brush->planes[2].dist) > 0.01f || fabs(DotProduct(brush->points[0].v, brush->planes[2].normal) - brush->planes[2].dist) > 0.01f)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->planes[2].normal[0], brush->planes[2].normal[1], brush->planes[2].normal[2], brush->planes[2].dist);
-                               if (fabs(DotProduct(brush->points[0].v, brush->planes[3].normal) - brush->planes[3].dist) > 0.01f || fabs(DotProduct(brush->points[1].v, brush->planes[3].normal) - brush->planes[3].dist) > 0.01f)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[0].v[0], brush->points[0].v[1], brush->points[0].v[2], brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->planes[3].normal[0], brush->planes[3].normal[1], brush->planes[3].normal[2], brush->planes[3].dist);
-                               if (fabs(DotProduct(brush->points[1].v, brush->planes[4].normal) - brush->planes[4].dist) > 0.01f || fabs(DotProduct(brush->points[2].v, brush->planes[4].normal) - brush->planes[4].dist) > 0.01f)
-                                       Con_Printf("Collision_CalcPlanesForPolygonBrushFloat: edge 0 (%f %f %f to %f %f %f) off front plane 2 (%f %f %f %f)\n", brush->points[1].v[0], brush->points[1].v[1], brush->points[1].v[2], brush->points[2].v[0], brush->points[2].v[1], brush->points[2].v[2], brush->planes[4].normal[0], brush->planes[4].normal[1], brush->planes[4].normal[2], brush->planes[4].dist);
-                       }
-               }
+               // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
+               // note that some of these exist in q3bsp bspline patches
+               brush->numplanes = 0;
+               return;
        }
-       else
+
+       // there are 5 planes (front, back, sides) and 3 edges
+       brush->numplanes = 5;
+       brush->numedgedirs = 3;
+       VectorNormalize(brush->planes[0].normal);
+       brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
+       VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
+       brush->planes[1].dist = -brush->planes[0].dist;
+       // edge directions are easy to calculate
+       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);
+       VectorCopy(edge0, brush->edgedirs[0].v);
+       VectorCopy(edge1, brush->edgedirs[1].v);
+       VectorCopy(edge2, brush->edgedirs[2].v);
+       // now select an algorithm to generate the side planes
+       if (collision_triangle_bevelsides.integer)
+       {
+               // 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
+               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);
+               VectorNormalize(brush->planes[2].normal);
+               VectorNormalize(brush->planes[3].normal);
+               VectorNormalize(brush->planes[4].normal);
+               VectorAdd(brush->planes[2].normal, brush->planes[0].normal, brush->planes[2].normal);
+               VectorAdd(brush->planes[3].normal, brush->planes[0].normal, brush->planes[3].normal);
+               VectorAdd(brush->planes[4].normal, brush->planes[0].normal, brush->planes[4].normal);
+               VectorNormalize(brush->planes[2].normal);
+               VectorNormalize(brush->planes[3].normal);
+               VectorNormalize(brush->planes[4].normal);
+       }
+       else if (collision_triangle_axialsides.integer)
        {
-               // choose best surface normal for polygon's plane
-               bestdist = 0;
-               for (i = 0, p = brush->points + 1;i < brush->numpoints - 2;i++, p++)
+               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++)
                {
-                       VectorSubtract(p[-1].v, p[0].v, edge0);
-                       VectorSubtract(p[1].v, p[0].v, edge1);
-                       CrossProduct(edge0, edge1, normal);
-                       //TriangleNormal(p[-1].v, p[0].v, p[1].v, normal);
-                       dist = DotProduct(normal, normal);
-                       if (i == 0 || bestdist < dist)
+                       dist = fabs(brush->planes[0].normal[i]);
+                       if (bestdist < dist)
                        {
                                bestdist = dist;
-                               VectorCopy(normal, brush->planes->normal);
+                               best = i;
                        }
                }
-               if (bestdist < 0.0001f)
-               {
-                       // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
-                       brush->numplanes = 0;
-                       return;
-               }
+               VectorClear(projectionnormal);
+               if (brush->planes[0].normal[best] < 0)
+                       projectionnormal[best] = -1;
                else
-               {
-                       brush->numplanes = brush->numpoints + 2;
-                       VectorNormalize(brush->planes->normal);
-                       brush->planes->dist = DotProduct(brush->points->v, brush->planes->normal);
-
-                       // negate plane to create other side
-                       VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
-                       brush->planes[1].dist = -brush->planes[0].dist;
-                       for (i = 0, p = brush->points + (brush->numpoints - 1), p2 = brush->points;i < brush->numpoints;i++, p = p2, p2++)
-                       {
-                               VectorSubtract(p->v, p2->v, edge0);
-                               CrossProduct(edge0, brush->planes->normal, brush->planes[i + 2].normal);
-                               VectorNormalize(brush->planes[i + 2].normal);
-                               brush->planes[i + 2].dist = DotProduct(p->v, brush->planes[i + 2].normal);
-                       }
-               }
+                       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);
+               VectorNormalize(brush->planes[2].normal);
+               VectorNormalize(brush->planes[3].normal);
+               VectorNormalize(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);
+               VectorNormalize(brush->planes[2].normal);
+               VectorNormalize(brush->planes[3].normal);
+               VectorNormalize(brush->planes[4].normal);
        }
+       brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
+       brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
+       brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
 
-       if (developer.integer >= 100)
+       if (developer_extra.integer)
        {
+               int i;
                // validity check - will be disabled later
                Collision_ValidateBrush(brush);
                for (i = 0;i < brush->numplanes;i++)
@@ -539,96 +550,108 @@ void Collision_CalcPlanesForPolygonBrushFloat(colbrushf_t *brush)
                        int j;
                        for (j = 0, p = brush->points;j < brush->numpoints;j++, p++)
                                if (DotProduct(p->v, brush->planes[i].normal) > brush->planes[i].dist + COLLISION_PLANE_DIST_EPSILON)
-                                       Con_Printf("Error in brush plane generation, plane %i\n", i);
+                                       Con_DPrintf("Error in brush plane generation, plane %i\n", i);
                }
        }
 }
 
-colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents)
-{
-       colbrushf_t *brush;
-       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 = (colplanef_t *)(brush + 1);
-       brush->points = (colpointf_t *)points;
-       Sys_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...");
-       return brush;
-}
-
 // 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)
+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)
 {
-       int nplane, nplane2, hitq3surfaceflags = 0;
-       float enterfrac = -1, leavefrac = 1, d1, d2, s, e, ie, f, imove, enterfrac2 = -1;
-       const colplanef_t *startplane, *endplane;
-       plane_t newimpactplane;
-       texture_t *hittexture = NULL;
-
-       VectorClear(newimpactplane.normal);
-       newimpactplane.dist = 0;
-
-       for (nplane = 0;nplane < thatbrush_start->numplanes + thisbrush_start->numplanes;nplane++)
+       int nplane, nplane2, nedge1, nedge2, hitq3surfaceflags = 0;
+       int tracenumedgedirs = trace_start->numedgedirs;
+       //int othernumedgedirs = other_start->numedgedirs;
+       int tracenumpoints = trace_start->numpoints;
+       int othernumpoints = other_start->numpoints;
+       int numplanes1 = other_start->numplanes;
+       int numplanes2 = numplanes1 + trace_start->numplanes;
+       int numplanes3 = numplanes2 + trace_start->numedgedirs * other_start->numedgedirs * 2;
+       vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
+       vec4_t startplane;
+       vec4_t endplane;
+       vec4_t newimpactplane;
+       const texture_t *hittexture = NULL;
+       vec_t startdepth = 1;
+       vec3_t startdepthnormal;
+       const texture_t *starttexture = NULL;
+
+       VectorClear(startdepthnormal);
+       Vector4Clear(newimpactplane);
+
+       // fast case for AABB vs compiled brushes (which begin with AABB planes and also have precomputed bevels for AABB collisions)
+       if (trace_start->isaabb && other_start->hasaabbplanes)
+               numplanes3 = numplanes2 = numplanes1;
+
+       // Separating Axis Theorem:
+       // if a supporting vector (plane normal) can be found that separates two
+       // objects, they are not colliding.
+       //
+       // Minkowski Sum:
+       // reduce the size of one object to a point while enlarging the other to
+       // represent the space that point can not occupy.
+       //
+       // try every plane we can construct between the two brushes and measure
+       // the distance between them.
+       for (nplane = 0;nplane < numplanes3;nplane++)
        {
-               nplane2 = nplane;
-               if (nplane2 >= thatbrush_start->numplanes)
+               if (nplane < numplanes1)
                {
-                       nplane2 -= thatbrush_start->numplanes;
-                       startplane = thisbrush_start->planes + nplane2;
-                       endplane = thisbrush_end->planes + nplane2;
-                       if (developer.integer >= 100)
-                       {
-                               // 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_Print("Collision_TraceBrushBrushFloat: degenerate thisbrush plane!\n");
-                                       return;
-                               }
-                               f = furthestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints);
-                               if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
-                                       Con_Printf("startplane->dist %f != calculated %f (thisbrush_start)\n", startplane->dist, f);
-                       }
-                       s = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                       e = furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints);
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - s - collision_startnudge.value;
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - e - collision_endnudge.value;
+                       nplane2 = nplane;
+                       VectorCopy(other_start->planes[nplane2].normal, startplane);
+                       VectorCopy(other_end->planes[nplane2].normal, endplane);
+               }
+               else if (nplane < numplanes2)
+               {
+                       nplane2 = nplane - numplanes1;
+                       VectorCopy(trace_start->planes[nplane2].normal, startplane);
+                       VectorCopy(trace_end->planes[nplane2].normal, endplane);
                }
                else
                {
-                       startplane = thatbrush_start->planes + nplane2;
-                       endplane = thatbrush_end->planes + nplane2;
-                       if (developer.integer >= 100)
+                       // pick an edgedir from each brush and cross them
+                       nplane2 = nplane - numplanes2;
+                       nedge1 = nplane2 >> 1;
+                       nedge2 = nedge1 / tracenumedgedirs;
+                       nedge1 -= nedge2 * tracenumedgedirs;
+                       if (nplane2 & 1)
                        {
-                               // 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_Print("Collision_TraceBrushBrushFloat: degenerate thatbrush plane!\n");
-                                       return;
-                               }
-                               f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                               if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
-                                       Con_Printf("startplane->dist %f != calculated %f (thatbrush_start)\n", startplane->dist, f);
+                               CrossProduct(trace_start->edgedirs[nedge1].v, other_start->edgedirs[nedge2].v, startplane);
+                               CrossProduct(trace_end->edgedirs[nedge1].v, other_end->edgedirs[nedge2].v, endplane);
+                       }
+                       else
+                       {
+                               CrossProduct(other_start->edgedirs[nedge2].v, trace_start->edgedirs[nedge1].v, startplane);
+                               CrossProduct(other_end->edgedirs[nedge2].v, trace_end->edgedirs[nedge1].v, endplane);
                        }
-                       s = startplane->dist;
-                       e = endplane->dist;
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - s - collision_startnudge.value;
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - e - collision_endnudge.value;
+                       if (VectorLength2(startplane) < COLLISION_EDGECROSS_MINLENGTH2 || VectorLength2(endplane) < COLLISION_EDGECROSS_MINLENGTH2)
+                               continue; // degenerate crossproducts
+                       VectorNormalize(startplane);
+                       VectorNormalize(endplane);
+               }
+               startplane[3] = furthestplanedist_float(startplane, other_start->points, othernumpoints);
+               endplane[3] = furthestplanedist_float(endplane, other_end->points, othernumpoints);
+               startdist = nearestplanedist_float(startplane, trace_start->points, tracenumpoints) - startplane[3];
+               enddist = nearestplanedist_float(endplane, trace_end->points, tracenumpoints) - endplane[3];
+               //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
+
+               // aside from collisions, this is also used for error correction
+               if (startdist <= 0.0f && nplane < numplanes1 && (startdepth < startdist || startdepth == 1))
+               {
+                       startdepth = startdist;
+                       VectorCopy(startplane, startdepthnormal);
+                       starttexture = other_start->planes[nplane2].texture;
                }
-               //Con_Printf("%c%i: d1 = %f, d2 = %f, d1 / (d1 - d2) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, d1, d2, d1 / (d1 - d2));
 
-               if (d1 > d2)
+               if (startdist > enddist)
                {
                        // moving into brush
-                       if (d2 >= collision_enternudge.value)
+                       if (enddist > 0.0f)
                                return;
-                       if (d1 > 0)
+                       if (startdist >= 0)
                        {
                                // enter
-                               imove = 1 / (d1 - d2);
-                               f = (d1 - collision_enternudge.value) * imove;
-                               if (f < 0)
-                                       f = 0;
+                               imove = 1 / (startdist - enddist);
+                               f = startdist * imove;
                                // check if this will reduce the collision time range
                                if (enterfrac < f)
                                {
@@ -637,35 +660,50 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                        // if the collision time range is now empty, no collision
                                        if (enterfrac > leavefrac)
                                                return;
+                                       // calculate the nudged fraction and impact normal we'll
+                                       // need if we accept this collision later
+                                       enterfrac2 = (startdist - collision_impactnudge.value) * imove;
                                        // if the collision would be further away than the trace's
                                        // existing collision data, we don't care about this
                                        // collision
-                                       if (enterfrac > trace->realfraction)
+                                       if (enterfrac2 >= trace->fraction)
                                                return;
-                                       // calculate the nudged fraction and impact normal we'll
-                                       // need if we accept this collision later
-                                       enterfrac2 = (d1 - collision_impactnudge.value) * imove;
                                        ie = 1.0f - enterfrac;
-                                       newimpactplane.normal[0] = startplane->normal[0] * ie + endplane->normal[0] * enterfrac;
-                                       newimpactplane.normal[1] = startplane->normal[1] * ie + endplane->normal[1] * enterfrac;
-                                       newimpactplane.normal[2] = startplane->normal[2] * ie + endplane->normal[2] * enterfrac;
-                                       newimpactplane.dist      = s                     * ie + e                   * enterfrac;
-                                       hitq3surfaceflags = startplane->q3surfaceflags;
-                                       hittexture = startplane->texture;
+                                       newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
+                                       newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
+                                       newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
+                                       newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
+                                       if (nplane < numplanes1)
+                                       {
+                                               // use the plane from other
+                                               nplane2 = nplane;
+                                               hitq3surfaceflags = other_start->planes[nplane2].q3surfaceflags;
+                                               hittexture = other_start->planes[nplane2].texture;
+                                       }
+                                       else if (nplane < numplanes2)
+                                       {
+                                               // use the plane from trace
+                                               nplane2 = nplane - numplanes1;
+                                               hitq3surfaceflags = trace_start->planes[nplane2].q3surfaceflags;
+                                               hittexture = trace_start->planes[nplane2].texture;
+                                       }
+                                       else
+                                       {
+                                               hitq3surfaceflags = other_start->q3surfaceflags;
+                                               hittexture = other_start->texture;
+                                       }
                                }
                        }
                }
                else
                {
                        // moving out of brush
-                       if (d1 > 0)
+                       if (startdist >= 0)
                                return;
-                       if (d2 > 0)
+                       if (enddist > 0)
                        {
                                // leave
-                               f = (d1 + collision_leavenudge.value) / (d1 - d2);
-                               if (f > 1)
-                                       f = 1;
+                               f = startdist / (startdist - enddist);
                                // check if this will reduce the collision time range
                                if (leavefrac > f)
                                {
@@ -687,78 +725,101 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
        {
                // started outside, and overlaps, therefore there is a collision here
                // store out the impact information
-               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               if ((trace->hitsupercontentsmask & other_start->supercontents) && !(trace->skipsupercontentsmask & other_start->supercontents) && !(trace->skipmaterialflagsmask & (hittexture ? hittexture->currentmaterialflags : 0)))
                {
-                       trace->hitsupercontents = thatbrush_start->supercontents;
+                       trace->hitsupercontents = other_start->supercontents;
                        trace->hitq3surfaceflags = hitq3surfaceflags;
                        trace->hittexture = hittexture;
-                       trace->realfraction = bound(0, enterfrac, 1);
                        trace->fraction = bound(0, enterfrac2, 1);
-                       if (collision_prefernudgedfraction.integer)
-                               trace->realfraction = trace->fraction;
-                       trace->plane = newimpactplane;
+                       VectorCopy(newimpactplane, trace->plane.normal);
+                       trace->plane.dist = newimpactplane[3];
                }
        }
        else
        {
                // started inside, update startsolid and friends
-               trace->startsupercontents |= thatbrush_start->supercontents;
-               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               trace->startsupercontents |= other_start->supercontents;
+               if ((trace->hitsupercontentsmask & other_start->supercontents) && !(trace->skipsupercontentsmask & other_start->supercontents) && !(trace->skipmaterialflagsmask & (starttexture ? starttexture->currentmaterialflags : 0)))
                {
                        trace->startsolid = true;
                        if (leavefrac < 1)
                                trace->allsolid = true;
-                       trace->plane = newimpactplane;
+                       VectorCopy(newimpactplane, trace->plane.normal);
+                       trace->plane.dist = newimpactplane[3];
+                       if (trace->startdepth > startdepth)
+                       {
+                               trace->startdepth = startdepth;
+                               VectorCopy(startdepthnormal, trace->startdepthnormal);
+                               trace->starttexture = starttexture;
+                       }
                }
        }
 }
 
-// NOTE: start and end brush pair must have same numplanes/numpoints
-void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
+// NOTE: start and end of each brush pair must have same numplanes/numpoints
+void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *other_start, const colbrushf_t *other_end)
 {
        int nplane, hitq3surfaceflags = 0;
-       float enterfrac = -1, leavefrac = 1, d1, d2, ie, f, imove, enterfrac2 = -1;
-       const colplanef_t *startplane, *endplane;
-       plane_t newimpactplane;
-       texture_t *hittexture = NULL;
-
-       VectorClear(newimpactplane.normal);
-       newimpactplane.dist = 0;
+       int numplanes = other_start->numplanes;
+       vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
+       vec4_t startplane;
+       vec4_t endplane;
+       vec4_t newimpactplane;
+       const texture_t *hittexture = NULL;
+       vec_t startdepth = 1;
+       vec3_t startdepthnormal;
+       const texture_t *starttexture = NULL;
+
+       if (collision_debug_tracelineasbox.integer)
+       {
+               colboxbrushf_t thisbrush_start, thisbrush_end;
+               Collision_BrushForBox(&thisbrush_start, linestart, linestart, 0, 0, NULL);
+               Collision_BrushForBox(&thisbrush_end, lineend, lineend, 0, 0, NULL);
+               Collision_TraceBrushBrushFloat(trace, &thisbrush_start.brush, &thisbrush_end.brush, other_start, other_end);
+               return;
+       }
 
-       for (nplane = 0;nplane < thatbrush_start->numplanes;nplane++)
+       VectorClear(startdepthnormal);
+       Vector4Clear(newimpactplane);
+
+       // Separating Axis Theorem:
+       // if a supporting vector (plane normal) can be found that separates two
+       // objects, they are not colliding.
+       //
+       // Minkowski Sum:
+       // reduce the size of one object to a point while enlarging the other to
+       // represent the space that point can not occupy.
+       //
+       // try every plane we can construct between the two brushes and measure
+       // the distance between them.
+       for (nplane = 0;nplane < numplanes;nplane++)
        {
-               startplane = thatbrush_start->planes + nplane;
-               endplane = thatbrush_end->planes + nplane;
-               d1 = DotProduct(startplane->normal, linestart) - startplane->dist - collision_startnudge.value;
-               d2 = DotProduct(endplane->normal, lineend) - endplane->dist - collision_endnudge.value;
-               if (developer.integer >= 100)
+               VectorCopy(other_start->planes[nplane].normal, startplane);
+               startplane[3] = other_start->planes[nplane].dist;
+               VectorCopy(other_end->planes[nplane].normal, endplane);
+               endplane[3] = other_end->planes[nplane].dist;
+               startdist = DotProduct(linestart, startplane) - startplane[3];
+               enddist = DotProduct(lineend, endplane) - endplane[3];
+               //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
+
+               // aside from collisions, this is also used for error correction
+               if (startdist <= 0.0f && (startdepth < startdist || startdepth == 1))
                {
-                       // 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_Print("Collision_TraceLineBrushFloat: degenerate plane!\n");
-                               return;
-                       }
-                       if (thatbrush_start->numpoints)
-                       {
-                               f = furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints);
-                               if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
-                                       Con_Printf("startplane->dist %f != calculated %f\n", startplane->dist, f);
-                       }
+                       startdepth = startdist;
+                       VectorCopy(startplane, startdepthnormal);
+                       starttexture = other_start->planes[nplane].texture;
                }
 
-               if (d1 > d2)
+               if (startdist > enddist)
                {
                        // moving into brush
-                       if (d2 >= collision_enternudge.value)
+                       if (enddist > 0.0f)
                                return;
-                       if (d1 > 0)
+                       if (startdist > 0)
                        {
                                // enter
-                               imove = 1 / (d1 - d2);
-                               f = (d1 - collision_enternudge.value) * imove;
-                               if (f < 0)
-                                       f = 0;
+                               imove = 1 / (startdist - enddist);
+                               f = startdist * imove;
                                // check if this will reduce the collision time range
                                if (enterfrac < f)
                                {
@@ -767,33 +828,33 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
                                        // if the collision time range is now empty, no collision
                                        if (enterfrac > leavefrac)
                                                return;
+                                       // calculate the nudged fraction and impact normal we'll
+                                       // need if we accept this collision later
+                                       enterfrac2 = (startdist - collision_impactnudge.value) * imove;
                                        // if the collision would be further away than the trace's
                                        // existing collision data, we don't care about this
                                        // collision
-                                       if (enterfrac > trace->realfraction)
+                                       if (enterfrac2 >= trace->fraction)
                                                return;
-                                       // calculate the nudged fraction and impact normal we'll
-                                       // need if we accept this collision later
-                                       enterfrac2 = (d1 - collision_impactnudge.value) * imove;
                                        ie = 1.0f - enterfrac;
-                                       newimpactplane.normal[0] = startplane->normal[0] * ie + endplane->normal[0] * enterfrac;
-                                       newimpactplane.normal[1] = startplane->normal[1] * ie + endplane->normal[1] * enterfrac;
-                                       newimpactplane.normal[2] = startplane->normal[2] * ie + endplane->normal[2] * enterfrac;
-                                       newimpactplane.dist      = startplane->dist      * ie + endplane->dist      * enterfrac;
-                                       hitq3surfaceflags = startplane->q3surfaceflags;
-                                       hittexture = startplane->texture;
+                                       newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
+                                       newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
+                                       newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
+                                       newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
+                                       hitq3surfaceflags = other_start->planes[nplane].q3surfaceflags;
+                                       hittexture = other_start->planes[nplane].texture;
                                }
                        }
                }
                else
                {
                        // moving out of brush
-                       if (d1 > 0)
+                       if (startdist > 0)
                                return;
-                       if (d2 > 0)
+                       if (enddist > 0)
                        {
                                // leave
-                               f = (d1 + collision_leavenudge.value) / (d1 - d2);
+                               f = startdist / (startdist - enddist);
                                // check if this will reduce the collision time range
                                if (leavefrac > f)
                                {
@@ -815,28 +876,33 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
        {
                // started outside, and overlaps, therefore there is a collision here
                // store out the impact information
-               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               if ((trace->hitsupercontentsmask & other_start->supercontents) && !(trace->skipsupercontentsmask & other_start->supercontents) && !(trace->skipmaterialflagsmask & (hittexture ? hittexture->currentmaterialflags : 0)))
                {
-                       trace->hitsupercontents = thatbrush_start->supercontents;
+                       trace->hitsupercontents = other_start->supercontents;
                        trace->hitq3surfaceflags = hitq3surfaceflags;
                        trace->hittexture = hittexture;
-                       trace->realfraction = bound(0, enterfrac, 1);
                        trace->fraction = bound(0, enterfrac2, 1);
-                       if (collision_prefernudgedfraction.integer)
-                               trace->realfraction = trace->fraction;
-                       trace->plane = newimpactplane;
+                       VectorCopy(newimpactplane, trace->plane.normal);
+                       trace->plane.dist = newimpactplane[3];
                }
        }
        else
        {
                // started inside, update startsolid and friends
-               trace->startsupercontents |= thatbrush_start->supercontents;
-               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               trace->startsupercontents |= other_start->supercontents;
+               if ((trace->hitsupercontentsmask & other_start->supercontents) && !(trace->skipsupercontentsmask & other_start->supercontents) && !(trace->skipmaterialflagsmask & (starttexture ? starttexture->currentmaterialflags : 0)))
                {
                        trace->startsolid = true;
                        if (leavefrac < 1)
                                trace->allsolid = true;
-                       trace->plane = newimpactplane;
+                       VectorCopy(newimpactplane, trace->plane.normal);
+                       trace->plane.dist = newimpactplane[3];
+                       if (trace->startdepth > startdepth)
+                       {
+                               trace->startdepth = startdepth;
+                               VectorCopy(startdepthnormal, trace->startdepthnormal);
+                               trace->starttexture = starttexture;
+                       }
                }
        }
 }
@@ -854,24 +920,69 @@ qboolean Collision_PointInsideBrushFloat(const vec3_t point, const colbrushf_t *
        return true;
 }
 
-void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
+void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t linestart, const colbrushf_t *other_start)
 {
-       if (!Collision_PointInsideBrushFloat(point, thatbrush))
-               return;
+       int nplane;
+       int numplanes = other_start->numplanes;
+       vec_t startdist;
+       vec4_t startplane;
+       vec4_t newimpactplane;
+       vec_t startdepth = 1;
+       vec3_t startdepthnormal;
+       const texture_t *starttexture = NULL;
+
+       VectorClear(startdepthnormal);
+       Vector4Clear(newimpactplane);
+
+       // Separating Axis Theorem:
+       // if a supporting vector (plane normal) can be found that separates two
+       // objects, they are not colliding.
+       //
+       // Minkowski Sum:
+       // reduce the size of one object to a point while enlarging the other to
+       // represent the space that point can not occupy.
+       //
+       // try every plane we can construct between the two brushes and measure
+       // the distance between them.
+       for (nplane = 0; nplane < numplanes; nplane++)
+       {
+               VectorCopy(other_start->planes[nplane].normal, startplane);
+               startplane[3] = other_start->planes[nplane].dist;
+               startdist = DotProduct(linestart, startplane) - startplane[3];
+
+               if (startdist > 0)
+                       return;
+
+               // aside from collisions, this is also used for error correction
+               if (startdepth < startdist || startdepth == 1)
+               {
+                       startdepth = startdist;
+                       VectorCopy(startplane, startdepthnormal);
+                       starttexture = other_start->planes[nplane].texture;
+               }
+       }
+
+       // at this point we know the trace overlaps the brush because it was not
+       // rejected at any point in the loop above
 
-       trace->startsupercontents |= thatbrush->supercontents;
-       if (trace->hitsupercontentsmask & thatbrush->supercontents)
+       // started inside, update startsolid and friends
+       trace->startsupercontents |= other_start->supercontents;
+       if ((trace->hitsupercontentsmask & other_start->supercontents) && !(trace->skipsupercontentsmask & other_start->supercontents) && !(trace->skipmaterialflagsmask & (starttexture ? starttexture->currentmaterialflags : 0)))
        {
                trace->startsolid = true;
                trace->allsolid = true;
+               VectorCopy(newimpactplane, trace->plane.normal);
+               trace->plane.dist = newimpactplane[3];
+               if (trace->startdepth > startdepth)
+               {
+                       trace->startdepth = startdepth;
+                       VectorCopy(startdepthnormal, trace->startdepthnormal);
+                       trace->starttexture = starttexture;
+               }
        }
 }
 
-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)
+static void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
 {
        int i;
        for (i = 0;i < numpoints;i++)
@@ -882,39 +993,31 @@ void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t
        }
 }
 
-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_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.planes = polyf_planes;
-       polyf_brush.supercontents = supercontents;
-       polyf_brush.points = polyf_points;
-       Collision_SnapCopyPoints(polyf_brush.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);
-}
-
-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, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
+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)
 {
        int i;
-       polyf_brush.numpoints = 3;
-       polyf_brush.numplanes = 5;
-       polyf_brush.points = polyf_points;
-       polyf_brush.planes = polyf_planes;
-       polyf_brush.supercontents = supercontents;
-       for (i = 0;i < polyf_brush.numplanes;i++)
+       colpointf_t points[3];
+       colpointf_t edgedirs[3];
+       colplanef_t planes[5];
+       colbrushf_t brush;
+       memset(&brush, 0, sizeof(brush));
+       brush.isaabb = false;
+       brush.hasaabbplanes = false;
+       brush.numpoints = 3;
+       brush.numedgedirs = 3;
+       brush.numplanes = 5;
+       brush.points = points;
+       brush.edgedirs = edgedirs;
+       brush.planes = planes;
+       brush.supercontents = supercontents;
+       brush.q3surfaceflags = q3surfaceflags;
+       brush.texture = texture;
+       for (i = 0;i < brush.numplanes;i++)
        {
-               polyf_brush.planes[i].q3surfaceflags = q3surfaceflags;
-               polyf_brush.planes[i].texture = texture;
+               brush.planes[i].q3surfaceflags = q3surfaceflags;
+               brush.planes[i].texture = texture;
        }
-       if(stride)
+       if(stride > 0)
        {
                int k, cnt, tri;
                cnt = (numtriangles + stride - 1) / stride;
@@ -927,60 +1030,56 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
                                        tri = i * stride + k;
                                        if(tri >= numtriangles)
                                                break;
-                                       VectorCopy(vertex3f + element3i[tri * 3 + 0] * 3, polyf_points[0].v);
-                                       VectorCopy(vertex3f + element3i[tri * 3 + 1] * 3, polyf_points[1].v);
-                                       VectorCopy(vertex3f + element3i[tri * 3 + 2] * 3, polyf_points[2].v);
-                                       Collision_SnapCopyPoints(polyf_brush.numpoints, polyf_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);
+                                       VectorCopy(vertex3f + element3i[tri * 3 + 0] * 3, points[0].v);
+                                       VectorCopy(vertex3f + element3i[tri * 3 + 1] * 3, points[1].v);
+                                       VectorCopy(vertex3f + element3i[tri * 3 + 2] * 3, points[2].v);
+                                       Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+                                       Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
+                                       Collision_CalcPlanesForTriangleBrushFloat(&brush);
+                                       //Collision_PrintBrushAsQHull(&brush, "brush");
+                                       Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
                                }
                        }
                }
        }
-       else
+       else if(stride == 0)
        {
                for (i = 0;i < numtriangles;i++, element3i += 3)
                {
-                       if (TriangleOverlapsBox(vertex3f + element3i[0]*3, vertex3f + element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
+                       if (TriangleBBoxOverlapsBox(vertex3f + element3i[0]*3, vertex3f + element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
                        {
-                               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);
-                               Collision_SnapCopyPoints(polyf_brush.numpoints, polyf_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);
+                               VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
+                               VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
+                               VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
+                               Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+                               Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
+                               Collision_CalcPlanesForTriangleBrushFloat(&brush);
+                               //Collision_PrintBrushAsQHull(&brush, "brush");
+                               Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
                        }
                }
        }
-}
-
-void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numpoints, const float *points, int supercontents)
-{
-       if (numpoints > 256)
+       else
        {
-               Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
-               return;
+               for (i = 0;i < numtriangles;i++, element3i += 3)
+               {
+                       VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
+                       VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
+                       VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
+                       Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+                       Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
+                       Collision_CalcPlanesForTriangleBrushFloat(&brush);
+                       //Collision_PrintBrushAsQHull(&brush, "brush");
+                       Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
+               }
        }
-       polyf_brush.numpoints = numpoints;
-       polyf_brush.numplanes = numpoints + 2;
-       //polyf_brush.points = (colpointf_t *)points;
-       polyf_brush.points = polyf_points;
-       Collision_SnapCopyPoints(polyf_brush.numpoints, (colpointf_t *)points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
-       polyf_brush.planes = polyf_planes;
-       polyf_brush.supercontents = supercontents;
-       Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
-       //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
-       Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
 }
 
-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, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
+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)
 {
        int i;
-#if 1
        // FIXME: snap vertices?
-       if(stride)
+       if(stride > 0)
        {
                int k, cnt, tri;
                cnt = (numtriangles + stride - 1) / stride;
@@ -1003,186 +1102,99 @@ void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart
                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, supercontents, q3surfaceflags, texture);
        }
-#else
-       polyf_brush.numpoints = 3;
-       polyf_brush.numplanes = 5;
-       polyf_brush.points = polyf_points;
-       polyf_brush.planes = polyf_planes;
-       polyf_brush.supercontents = supercontents;
-       for (i = 0;i < polyf_brush.numplanes;i++)
-       {
-               polyf_brush.planes[i].supercontents = supercontents;
-               polyf_brush.planes[i].q3surfaceflags = q3surfaceflags;
-               polyf_brush.planes[i].texture = texture;
-       }
-       for (i = 0;i < numtriangles;i++, element3i += 3)
-       {
-               if (TriangleOverlapsBox(vertex3f + element3i[0]*3, vertex3 + [element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
-               {
-                       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);
-                       Collision_SnapCopyPoints(polyf_brush.numpoints, polyf_points, polyf_points, COLLISION_SNAPSCALE, COLLISION_SNAP);
-                       Collision_CalcPlanesForPolygonBrushFloat(&polyf_brush);
-                       //Collision_PrintBrushAsQHull(&polyf_brush, "polyf_brush");
-                       Collision_TraceLineBrushFloat(trace, linestart, lineend, &polyf_brush, &polyf_brush);
-               }
-       }
-#endif
 }
 
-
-static colpointf_t polyf_pointsstart[256], polyf_pointsend[256];
-static colplanef_t polyf_planesstart[256 + 2], polyf_planesend[256 + 2];
-static colbrushf_t polyf_brushstart, polyf_brushend;
-
-void Collision_TraceBrushPolygonTransformFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numpoints, const float *points, const matrix4x4_t *polygonmatrixstart, const matrix4x4_t *polygonmatrixend, int supercontents, int q3surfaceflags, texture_t *texture)
+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)
 {
        int i;
-       if (numpoints > 256)
+       colpointf_t points[3];
+       colpointf_t edgedirs[3];
+       colplanef_t planes[5];
+       colbrushf_t brush;
+       memset(&brush, 0, sizeof(brush));
+       brush.isaabb = false;
+       brush.hasaabbplanes = false;
+       brush.numpoints = 3;
+       brush.numedgedirs = 3;
+       brush.numplanes = 5;
+       brush.points = points;
+       brush.edgedirs = edgedirs;
+       brush.planes = planes;
+       brush.supercontents = supercontents;
+       brush.q3surfaceflags = q3surfaceflags;
+       brush.texture = texture;
+       for (i = 0;i < brush.numplanes;i++)
        {
-               Con_Print("Polygon with more than 256 points not supported yet (fixme!)\n");
-               return;
+               brush.planes[i].q3surfaceflags = q3surfaceflags;
+               brush.planes[i].texture = texture;
        }
-       polyf_brushstart.numpoints = numpoints;
-       polyf_brushstart.numplanes = numpoints + 2;
-       polyf_brushstart.points = polyf_pointsstart;//(colpointf_t *)points;
-       polyf_brushstart.planes = polyf_planesstart;
-       polyf_brushstart.supercontents = supercontents;
-       for (i = 0;i < numpoints;i++)
-               Matrix4x4_Transform(polygonmatrixstart, points + i * 3, polyf_brushstart.points[i].v);
-       polyf_brushend.numpoints = numpoints;
-       polyf_brushend.numplanes = numpoints + 2;
-       polyf_brushend.points = polyf_pointsend;//(colpointf_t *)points;
-       polyf_brushend.planes = polyf_planesend;
-       polyf_brushend.supercontents = supercontents;
-       for (i = 0;i < numpoints;i++)
-               Matrix4x4_Transform(polygonmatrixend, points + i * 3, polyf_brushend.points[i].v);
-       for (i = 0;i < polyf_brushstart.numplanes;i++)
-       {
-               polyf_brushstart.planes[i].q3surfaceflags = q3surfaceflags;
-               polyf_brushstart.planes[i].texture = texture;
-       }
-       Collision_SnapCopyPoints(polyf_brushstart.numpoints, polyf_pointsstart, polyf_pointsstart, COLLISION_SNAPSCALE, COLLISION_SNAP);
-       Collision_SnapCopyPoints(polyf_brushend.numpoints, polyf_pointsend, polyf_pointsend, COLLISION_SNAPSCALE, COLLISION_SNAP);
-       Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushstart);
-       Collision_CalcPlanesForPolygonBrushFloat(&polyf_brushend);
-
-       //Collision_PrintBrushAsQHull(&polyf_brushstart, "polyf_brushstart");
-       //Collision_PrintBrushAsQHull(&polyf_brushend, "polyf_brushend");
-
-       Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &polyf_brushstart, &polyf_brushend);
+       VectorCopy(v0, points[0].v);
+       VectorCopy(v1, points[1].v);
+       VectorCopy(v2, points[2].v);
+       Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
+       Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
+       Collision_CalcPlanesForTriangleBrushFloat(&brush);
+       //Collision_PrintBrushAsQHull(&brush, "brush");
+       Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
 }
 
-
-
-#define MAX_BRUSHFORBOX 16
-static unsigned int brushforbox_index = 0;
-// note: this relies on integer overflow to be consistent with modulo
-// MAX_BRUSHFORBOX, or in other words, MAX_BRUSHFORBOX must be a power of two!
-static colpointf_t brushforbox_point[MAX_BRUSHFORBOX*8];
-static colplanef_t brushforbox_plane[MAX_BRUSHFORBOX*6];
-static colbrushf_t brushforbox_brush[MAX_BRUSHFORBOX];
-static colbrushf_t brushforpoint_brush[MAX_BRUSHFORBOX];
-
-void Collision_InitBrushForBox(void)
+void Collision_BrushForBox(colboxbrushf_t *boxbrush, const vec3_t mins, const vec3_t maxs, int supercontents, int q3surfaceflags, const texture_t *texture)
 {
        int i;
-       for (i = 0;i < MAX_BRUSHFORBOX;i++)
-       {
-               brushforbox_brush[i].numpoints = 8;
-               brushforbox_brush[i].numplanes = 6;
-               brushforbox_brush[i].points = brushforbox_point + i * 8;
-               brushforbox_brush[i].planes = brushforbox_plane + i * 6;
-               brushforpoint_brush[i].numpoints = 1;
-               brushforpoint_brush[i].numplanes = 0;
-               brushforpoint_brush[i].points = brushforbox_point + i * 8;
-               brushforpoint_brush[i].planes = brushforbox_plane + i * 6;
-       }
-}
-
-colbrushf_t *Collision_BrushForBox(const matrix4x4_t *matrix, const vec3_t mins, const vec3_t maxs, int supercontents, int q3surfaceflags, texture_t *texture)
-{
-       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
+       memset(boxbrush, 0, sizeof(*boxbrush));
+       boxbrush->brush.isaabb = true;
+       boxbrush->brush.hasaabbplanes = true;
+       boxbrush->brush.points = boxbrush->points;
+       boxbrush->brush.edgedirs = boxbrush->edgedirs;
+       boxbrush->brush.planes = boxbrush->planes;
+       boxbrush->brush.supercontents = supercontents;
+       boxbrush->brush.q3surfaceflags = q3surfaceflags;
+       boxbrush->brush.texture = texture;
        if (VectorCompare(mins, maxs))
        {
                // point brush
-               brush = brushforpoint_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
-               VectorCopy(mins, brush->points->v);
+               boxbrush->brush.numpoints = 1;
+               boxbrush->brush.numedgedirs = 0;
+               boxbrush->brush.numplanes = 0;
+               VectorCopy(mins, boxbrush->brush.points[0].v);
        }
        else
        {
-               brush = brushforbox_brush + ((brushforbox_index++) % MAX_BRUSHFORBOX);
-               // FIXME: optimize
-               for (i = 0;i < 8;i++)
-               {
-                       v[0] = i & 1 ? maxs[0] : mins[0];
-                       v[1] = i & 2 ? maxs[1] : mins[1];
-                       v[2] = i & 4 ? maxs[2] : mins[2];
-                       Matrix4x4_Transform(matrix, v, brush->points[i].v);
-               }
-               // FIXME: optimize!
+               boxbrush->brush.numpoints = 8;
+               boxbrush->brush.numedgedirs = 3;
+               boxbrush->brush.numplanes = 6;
+               // there are 8 points on a box
+               // there are 3 edgedirs on a box (both signs are tested in collision)
+               // there are 6 planes on a box
+               VectorSet(boxbrush->brush.points[0].v, mins[0], mins[1], mins[2]);
+               VectorSet(boxbrush->brush.points[1].v, maxs[0], mins[1], mins[2]);
+               VectorSet(boxbrush->brush.points[2].v, mins[0], maxs[1], mins[2]);
+               VectorSet(boxbrush->brush.points[3].v, maxs[0], maxs[1], mins[2]);
+               VectorSet(boxbrush->brush.points[4].v, mins[0], mins[1], maxs[2]);
+               VectorSet(boxbrush->brush.points[5].v, maxs[0], mins[1], maxs[2]);
+               VectorSet(boxbrush->brush.points[6].v, mins[0], maxs[1], maxs[2]);
+               VectorSet(boxbrush->brush.points[7].v, maxs[0], maxs[1], maxs[2]);
+               VectorSet(boxbrush->brush.edgedirs[0].v, 1, 0, 0);
+               VectorSet(boxbrush->brush.edgedirs[1].v, 0, 1, 0);
+               VectorSet(boxbrush->brush.edgedirs[2].v, 0, 0, 1);
+               VectorSet(boxbrush->brush.planes[0].normal, -1,  0,  0);boxbrush->brush.planes[0].dist = -mins[0];
+               VectorSet(boxbrush->brush.planes[1].normal,  1,  0,  0);boxbrush->brush.planes[1].dist =  maxs[0];
+               VectorSet(boxbrush->brush.planes[2].normal,  0, -1,  0);boxbrush->brush.planes[2].dist = -mins[1];
+               VectorSet(boxbrush->brush.planes[3].normal,  0,  1,  0);boxbrush->brush.planes[3].dist =  maxs[1];
+               VectorSet(boxbrush->brush.planes[4].normal,  0,  0, -1);boxbrush->brush.planes[4].dist = -mins[2];
+               VectorSet(boxbrush->brush.planes[5].normal,  0,  0,  1);boxbrush->brush.planes[5].dist =  maxs[2];
                for (i = 0;i < 6;i++)
                {
-                       VectorClear(v);
-                       v[i >> 1] = i & 1 ? 1 : -1;
-                       Matrix4x4_Transform3x3(matrix, v, brush->planes[i].normal);
-                       VectorNormalize(brush->planes[i].normal);
+                       boxbrush->brush.planes[i].q3surfaceflags = q3surfaceflags;
+                       boxbrush->brush.planes[i].texture = texture;
                }
        }
-       brush->supercontents = supercontents;
-       for (j = 0;j < brush->numplanes;j++)
-       {
-               brush->planes[j].q3surfaceflags = q3surfaceflags;
-               brush->planes[j].texture = texture;
-               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;
-}
-
-void Collision_ClipTrace_BrushBox(trace_t *trace, const vec3_t cmins, const vec3_t cmaxs, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask, int supercontents, int q3surfaceflags, texture_t *texture)
-{
-       colbrushf_t *boxbrush, *thisbrush_start, *thisbrush_end;
-       vec3_t startmins, startmaxs, endmins, endmaxs;
-
-       // create brushes for the collision
-       VectorAdd(start, mins, startmins);
-       VectorAdd(start, maxs, startmaxs);
-       VectorAdd(end, mins, endmins);
-       VectorAdd(end, maxs, endmaxs);
-       boxbrush = Collision_BrushForBox(&identitymatrix, cmins, cmaxs, supercontents, q3surfaceflags, texture);
-       thisbrush_start = Collision_BrushForBox(&identitymatrix, startmins, startmaxs, 0, 0, NULL);
-       thisbrush_end = Collision_BrushForBox(&identitymatrix, endmins, endmaxs, 0, 0, NULL);
-
-       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);
+       boxbrush->brush.supercontents = supercontents;
+       boxbrush->brush.q3surfaceflags = q3surfaceflags;
+       boxbrush->brush.texture = texture;
+       VectorSet(boxbrush->brush.mins, mins[0] - 1, mins[1] - 1, mins[2] - 1);
+       VectorSet(boxbrush->brush.maxs, maxs[0] + 1, maxs[1] + 1, maxs[2] + 1);
+       //Collision_ValidateBrush(&boxbrush->brush);
 }
 
 //pseudocode for detecting line/sphere overlap without calculating an impact point
@@ -1194,7 +1206,7 @@ void Collision_ClipTrace_BrushBox(trace_t *trace, const vec3_t cmins, const vec3
 // all the results are correct (impactpoint, impactnormal, and fraction)
 float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double *sphereorigin, double sphereradius, double *impactpoint, double *impactnormal)
 {
-       double dir[3], scale, v[3], deviationdist, impactdist, linelength;
+       double dir[3], scale, v[3], deviationdist2, impactdist, linelength;
        // make sure the impactpoint and impactnormal are valid even if there is
        // no collision
        VectorCopy(lineend, impactpoint);
@@ -1216,13 +1228,12 @@ float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double
        // of the line from the sphereorigin (deviation, how off-center it is)
        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)
+       deviationdist2 = sphereradius * sphereradius - VectorLength2(v);
+       // if squared offset length is outside the squared sphere radius, miss
+       if (deviationdist2 < 0)
                return 1; // miss (off to the side)
        // nudge back to find the correct impact distance
-       impactdist -= sphereradius - deviationdist/sphereradius;
+       impactdist -= sqrt(deviationdist2);
        if (impactdist >= linelength)
                return 1; // miss (not close enough)
        if (impactdist < 0)
@@ -1237,11 +1248,9 @@ float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double
        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, int supercontents, int q3surfaceflags, texture_t *texture)
+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)
 {
-#if 1
-       // more optimized
-       float d1, d2, d, f, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
+       float d1, d2, d, f, f2, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
 
        // this function executes:
        // 32 ops when line starts behind triangle
@@ -1298,11 +1307,12 @@ void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, co
        // 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
+       // 4 ops
        f = (d1 - faceplanedist) * d;
+       f2  = f - collision_impactnudge.value * d;
        // skip out if this impact is further away than previous ones
        // 1 ops
-       if (f > trace->realfraction)
+       if (f2 >= trace->fraction)
                return;
        // calculate the perfect impact point for classification of insidedness
        // 9 ops
@@ -1336,15 +1346,12 @@ void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, co
 
        // 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;
+       // skip if this trace should not be blocked by these contents
+       if (!(supercontents & trace->hitsupercontentsmask) || (supercontents & trace->skipsupercontentsmask) || (texture->currentmaterialflags & trace->skipmaterialflagsmask))
+               return;
 
-       if (collision_prefernudgedfraction.integer)
-               trace->realfraction = trace->fraction;
+       // store the new trace fraction
+       trace->fraction = f2;
 
        // store the new trace plane (because collisions only happen from
        // the front this is always simply the triangle normal, never flipped)
@@ -1355,152 +1362,6 @@ void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, co
        trace->hitsupercontents = supercontents;
        trace->hitq3surfaceflags = q3surfaceflags;
        trace->hittexture = texture;
-#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]);
-       trace->hitsupercontents = supercontents;
-       trace->hitq3surfaceflags = q3surfaceflags;
-       trace->hittexture = texture;
-#endif
-}
-
-typedef struct colbspnode_s
-{
-       mplane_t plane;
-       struct colbspnode_s *children[2];
-       // the node is reallocated or split if max is reached
-       int numcolbrushf;
-       int maxcolbrushf;
-       colbrushf_t **colbrushflist;
-       //int numcolbrushd;
-       //int maxcolbrushd;
-       //colbrushd_t **colbrushdlist;
-}
-colbspnode_t;
-
-typedef struct colbsp_s
-{
-       mempool_t *mempool;
-       colbspnode_t *nodes;
-}
-colbsp_t;
-
-colbsp_t *Collision_CreateCollisionBSP(mempool_t *mempool)
-{
-       colbsp_t *bsp;
-       bsp = (colbsp_t *)Mem_Alloc(mempool, sizeof(colbsp_t));
-       bsp->mempool = mempool;
-       bsp->nodes = (colbspnode_t *)Mem_Alloc(bsp->mempool, sizeof(colbspnode_t));
-       return bsp;
-}
-
-void Collision_FreeCollisionBSPNode(colbspnode_t *node)
-{
-       if (node->children[0])
-               Collision_FreeCollisionBSPNode(node->children[0]);
-       if (node->children[1])
-               Collision_FreeCollisionBSPNode(node->children[1]);
-       while (--node->numcolbrushf)
-               Mem_Free(node->colbrushflist[node->numcolbrushf]);
-       //while (--node->numcolbrushd)
-       //      Mem_Free(node->colbrushdlist[node->numcolbrushd]);
-       Mem_Free(node);
-}
-
-void Collision_FreeCollisionBSP(colbsp_t *bsp)
-{
-       Collision_FreeCollisionBSPNode(bsp->nodes);
-       Mem_Free(bsp);
 }
 
 void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const colbrushf_t *end, vec3_t mins, vec3_t maxs, float startfrac, float endfrac)
@@ -1531,89 +1392,499 @@ void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const co
 
 //===========================================
 
-void Collision_ClipToGenericEntity(trace_t *trace, dp_model_t *model, int frame, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontentsmask)
+static void Collision_TranslateBrush(const vec3_t shift, colbrushf_t *brush)
+{
+       int i;
+       // now we can transform the data
+       for(i = 0; i < brush->numplanes; ++i)
+       {
+               brush->planes[i].dist += DotProduct(shift, brush->planes[i].normal);
+       }
+       for(i = 0; i < brush->numpoints; ++i)
+       {
+               VectorAdd(brush->points[i].v, shift, brush->points[i].v);
+       }
+       VectorAdd(brush->mins, shift, brush->mins);
+       VectorAdd(brush->maxs, shift, brush->maxs);
+}
+
+static void Collision_TransformBrush(const matrix4x4_t *matrix, colbrushf_t *brush)
+{
+       int i;
+       vec3_t v;
+       // we're breaking any AABB properties here...
+       brush->isaabb = false;
+       brush->hasaabbplanes = false;
+       // now we can transform the data
+       for(i = 0; i < brush->numplanes; ++i)
+       {
+               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_and_dist);
+       }
+       for(i = 0; i < brush->numedgedirs; ++i)
+       {
+               Matrix4x4_Transform(matrix, brush->edgedirs[i].v, v);
+               VectorCopy(v, brush->edgedirs[i].v);
+       }
+       for(i = 0; i < brush->numpoints; ++i)
+       {
+               Matrix4x4_Transform(matrix, brush->points[i].v, v);
+               VectorCopy(v, brush->points[i].v);
+       }
+       VectorCopy(brush->points[0].v, brush->mins);
+       VectorCopy(brush->points[0].v, brush->maxs);
+       for(i = 1; i < brush->numpoints; ++i)
+       {
+               if(brush->points[i].v[0] < brush->mins[0]) brush->mins[0] = brush->points[i].v[0];
+               if(brush->points[i].v[1] < brush->mins[1]) brush->mins[1] = brush->points[i].v[1];
+               if(brush->points[i].v[2] < brush->mins[2]) brush->mins[2] = brush->points[i].v[2];
+               if(brush->points[i].v[0] > brush->maxs[0]) brush->maxs[0] = brush->points[i].v[0];
+               if(brush->points[i].v[1] > brush->maxs[1]) brush->maxs[1] = brush->points[i].v[1];
+               if(brush->points[i].v[2] > brush->maxs[2]) brush->maxs[2] = brush->points[i].v[2];
+       }
+}
+
+typedef struct collision_cachedtrace_parameters_s
+{
+       dp_model_t *model;
+       vec3_t end;
+       vec3_t start;
+       int hitsupercontentsmask;
+       int skipsupercontentsmask;
+       int skipmaterialflagsmask;
+       matrix4x4_t matrix;
+}
+collision_cachedtrace_parameters_t;
+
+typedef struct collision_cachedtrace_s
+{
+       qboolean valid;
+       collision_cachedtrace_parameters_t p;
+       trace_t result;
+}
+collision_cachedtrace_t;
+
+static mempool_t *collision_cachedtrace_mempool;
+static collision_cachedtrace_t *collision_cachedtrace_array;
+static int collision_cachedtrace_firstfree;
+static int collision_cachedtrace_lastused;
+static int collision_cachedtrace_max;
+static unsigned char collision_cachedtrace_sequence;
+static int collision_cachedtrace_hashsize;
+static int *collision_cachedtrace_hash;
+static unsigned int *collision_cachedtrace_arrayfullhashindex;
+static unsigned int *collision_cachedtrace_arrayhashindex;
+static unsigned int *collision_cachedtrace_arraynext;
+static unsigned char *collision_cachedtrace_arrayused;
+static qboolean collision_cachedtrace_rebuildhash;
+
+void Collision_Cache_Reset(qboolean resetlimits)
+{
+       if (collision_cachedtrace_hash)
+               Mem_Free(collision_cachedtrace_hash);
+       if (collision_cachedtrace_array)
+               Mem_Free(collision_cachedtrace_array);
+       if (collision_cachedtrace_arrayfullhashindex)
+               Mem_Free(collision_cachedtrace_arrayfullhashindex);
+       if (collision_cachedtrace_arrayhashindex)
+               Mem_Free(collision_cachedtrace_arrayhashindex);
+       if (collision_cachedtrace_arraynext)
+               Mem_Free(collision_cachedtrace_arraynext);
+       if (collision_cachedtrace_arrayused)
+               Mem_Free(collision_cachedtrace_arrayused);
+       if (resetlimits || !collision_cachedtrace_max)
+               collision_cachedtrace_max = collision_cache.integer ? 128 : 1;
+       collision_cachedtrace_firstfree = 1;
+       collision_cachedtrace_lastused = 0;
+       collision_cachedtrace_hashsize = collision_cachedtrace_max;
+       collision_cachedtrace_array = (collision_cachedtrace_t *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(collision_cachedtrace_t));
+       collision_cachedtrace_hash = (int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_hashsize * sizeof(int));
+       collision_cachedtrace_arrayfullhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
+       collision_cachedtrace_arrayhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
+       collision_cachedtrace_arraynext = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
+       collision_cachedtrace_arrayused = (unsigned char *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned char));
+       collision_cachedtrace_sequence = 1;
+       collision_cachedtrace_rebuildhash = false;
+}
+
+void Collision_Cache_Init(mempool_t *mempool)
+{
+       collision_cachedtrace_mempool = mempool;
+       Collision_Cache_Reset(true);
+}
+
+static void Collision_Cache_RebuildHash(void)
+{
+       int index;
+       int range = collision_cachedtrace_lastused + 1;
+       unsigned char sequence = collision_cachedtrace_sequence;
+       int firstfree = collision_cachedtrace_max;
+       int lastused = 0;
+       int *hash = collision_cachedtrace_hash;
+       unsigned int hashindex;
+       unsigned int *arrayhashindex = collision_cachedtrace_arrayhashindex;
+       unsigned int *arraynext = collision_cachedtrace_arraynext;
+       collision_cachedtrace_rebuildhash = false;
+       memset(collision_cachedtrace_hash, 0, collision_cachedtrace_hashsize * sizeof(int));
+       for (index = 1;index < range;index++)
+       {
+               if (collision_cachedtrace_arrayused[index] == sequence)
+               {
+                       hashindex = arrayhashindex[index];
+                       arraynext[index] = hash[hashindex];
+                       hash[hashindex] = index;
+                       lastused = index;
+               }
+               else
+               {
+                       if (firstfree > index)
+                               firstfree = index;
+                       collision_cachedtrace_arrayused[index] = 0;
+               }
+       }
+       collision_cachedtrace_firstfree = firstfree;
+       collision_cachedtrace_lastused = lastused;
+}
+
+void Collision_Cache_NewFrame(void)
+{
+       if (collision_cache.integer)
+       {
+               if (collision_cachedtrace_max < 128)
+                       Collision_Cache_Reset(true);
+       }
+       else
+       {
+               if (collision_cachedtrace_max > 1)
+                       Collision_Cache_Reset(true);
+       }
+       // rebuild hash if sequence would overflow byte, otherwise increment
+       if (collision_cachedtrace_sequence == 255)
+       {
+               Collision_Cache_RebuildHash();
+               collision_cachedtrace_sequence = 1;
+       }
+       else
+       {
+               collision_cachedtrace_rebuildhash = true;
+               collision_cachedtrace_sequence++;
+       }
+}
+
+static unsigned int Collision_Cache_HashIndexForArray(unsigned int *array, unsigned int size)
+{
+       unsigned int i;
+       unsigned int hashindex = 0;
+       // this is a super-cheesy checksum, designed only for speed
+       for (i = 0;i < size;i++)
+               hashindex += array[i] * (1 + i);
+       return hashindex;
+}
+
+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, int skipsupercontentsmask, int skipmaterialflagsmask)
+{
+       int hashindex = 0;
+       unsigned int fullhashindex;
+       int index = 0;
+       int range;
+       unsigned char sequence = collision_cachedtrace_sequence;
+       int *hash = collision_cachedtrace_hash;
+       unsigned int *arrayfullhashindex = collision_cachedtrace_arrayfullhashindex;
+       unsigned int *arraynext = collision_cachedtrace_arraynext;
+       collision_cachedtrace_t *cached = collision_cachedtrace_array + index;
+       collision_cachedtrace_parameters_t params;
+       // all non-cached traces use the same index
+       if (!collision_cache.integer)
+               r_refdef.stats[r_stat_photoncache_traced]++;
+       else
+       {
+               // cached trace lookup
+               memset(&params, 0, sizeof(params));
+               params.model = model;
+               VectorCopy(start, params.start);
+               VectorCopy(end,   params.end);
+               params.hitsupercontentsmask = hitsupercontentsmask;
+               params.skipsupercontentsmask = skipsupercontentsmask;
+               params.skipmaterialflagsmask = skipmaterialflagsmask;
+               params.matrix = *matrix;
+               fullhashindex = Collision_Cache_HashIndexForArray((unsigned int *)&params, sizeof(params) / sizeof(unsigned int));
+               hashindex = (int)(fullhashindex % (unsigned int)collision_cachedtrace_hashsize);
+               for (index = hash[hashindex];index;index = arraynext[index])
+               {
+                       if (arrayfullhashindex[index] != fullhashindex)
+                               continue;
+                       cached = collision_cachedtrace_array + index;
+                       //if (memcmp(&cached->p, &params, sizeof(params)))
+                       if (cached->p.model != params.model
+                        || cached->p.end[0] != params.end[0]
+                        || cached->p.end[1] != params.end[1]
+                        || cached->p.end[2] != params.end[2]
+                        || cached->p.start[0] != params.start[0]
+                        || cached->p.start[1] != params.start[1]
+                        || cached->p.start[2] != params.start[2]
+                        || cached->p.hitsupercontentsmask != params.hitsupercontentsmask
+                        || cached->p.skipsupercontentsmask != params.skipsupercontentsmask
+                        || cached->p.skipmaterialflagsmask != params.skipmaterialflagsmask
+                        || cached->p.matrix.m[0][0] != params.matrix.m[0][0]
+                        || cached->p.matrix.m[0][1] != params.matrix.m[0][1]
+                        || cached->p.matrix.m[0][2] != params.matrix.m[0][2]
+                        || cached->p.matrix.m[0][3] != params.matrix.m[0][3]
+                        || cached->p.matrix.m[1][0] != params.matrix.m[1][0]
+                        || cached->p.matrix.m[1][1] != params.matrix.m[1][1]
+                        || cached->p.matrix.m[1][2] != params.matrix.m[1][2]
+                        || cached->p.matrix.m[1][3] != params.matrix.m[1][3]
+                        || cached->p.matrix.m[2][0] != params.matrix.m[2][0]
+                        || cached->p.matrix.m[2][1] != params.matrix.m[2][1]
+                        || cached->p.matrix.m[2][2] != params.matrix.m[2][2]
+                        || cached->p.matrix.m[2][3] != params.matrix.m[2][3]
+                        || cached->p.matrix.m[3][0] != params.matrix.m[3][0]
+                        || cached->p.matrix.m[3][1] != params.matrix.m[3][1]
+                        || cached->p.matrix.m[3][2] != params.matrix.m[3][2]
+                        || cached->p.matrix.m[3][3] != params.matrix.m[3][3]
+                       )
+                               continue;
+                       // found a matching trace in the cache
+                       r_refdef.stats[r_stat_photoncache_cached]++;
+                       cached->valid = true;
+                       collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
+                       return cached;
+               }
+               r_refdef.stats[r_stat_photoncache_traced]++;
+               // find an unused cache entry
+               for (index = collision_cachedtrace_firstfree, range = collision_cachedtrace_max;index < range;index++)
+                       if (collision_cachedtrace_arrayused[index] == 0)
+                               break;
+               if (index == range)
+               {
+                       // all claimed, but probably some are stale...
+                       for (index = 1, range = collision_cachedtrace_max;index < range;index++)
+                               if (collision_cachedtrace_arrayused[index] != sequence)
+                                       break;
+                       if (index < range)
+                       {
+                               // found a stale one, rebuild the hash
+                               Collision_Cache_RebuildHash();
+                       }
+                       else
+                       {
+                               // we need to grow the cache
+                               collision_cachedtrace_max *= 2;
+                               Collision_Cache_Reset(false);
+                               index = 1;
+                       }
+               }
+               // link the new cache entry into the hash bucket
+               collision_cachedtrace_firstfree = index + 1;
+               if (collision_cachedtrace_lastused < index)
+                       collision_cachedtrace_lastused = index;
+               cached = collision_cachedtrace_array + index;
+               collision_cachedtrace_arraynext[index] = collision_cachedtrace_hash[hashindex];
+               collision_cachedtrace_hash[hashindex] = index;
+               collision_cachedtrace_arrayhashindex[index] = hashindex;
+               cached->valid = false;
+               cached->p = params;
+               collision_cachedtrace_arrayfullhashindex[index] = fullhashindex;
+               collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
+       }
+       return cached;
+}
+
+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, int skipsupercontentsmask, int skipmaterialflagsmask)
+{
+       collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, matrix, inversematrix, start, end, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       if (cached->valid)
+       {
+               *trace = cached->result;
+               return;
+       }
+
+       Collision_ClipLineToGenericEntity(trace, model, NULL, NULL, vec3_origin, vec3_origin, 0, matrix, inversematrix, start, end, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask, collision_extendmovelength.value, true);
+
+       cached->result = *trace;
+}
+
+void Collision_Cache_ClipLineToWorldSurfaces(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t end, int hitsupercontentsmask, int skipsupercontentsmask, int skipmaterialflagsmask)
+{
+       collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, &identitymatrix, &identitymatrix, start, end, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       if (cached->valid)
+       {
+               *trace = cached->result;
+               return;
+       }
+
+       Collision_ClipLineToWorld(trace, model, start, end, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask, collision_extendmovelength.value, true);
+
+       cached->result = *trace;
+}
+
+typedef struct extendtraceinfo_s
 {
-       float starttransformed[3], endtransformed[3];
+       trace_t *trace;
+       float realstart[3];
+       float realend[3];
+       float realdelta[3];
+       float extendstart[3];
+       float extendend[3];
+       float extenddelta[3];
+       float reallength;
+       float extendlength;
+       float scaletoextend;
+       float extend;
+}
+extendtraceinfo_t;
 
+static void Collision_ClipExtendPrepare(extendtraceinfo_t *extendtraceinfo, trace_t *trace, const vec3_t tstart, const vec3_t tend, float textend)
+{
        memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
-       VectorCopy(end, trace->endpos);
+       trace->fraction = 1;
 
-       Matrix4x4_Transform(inversematrix, start, starttransformed);
-       Matrix4x4_Transform(inversematrix, end, endtransformed);
+       extendtraceinfo->trace = trace;
+       VectorCopy(tstart, extendtraceinfo->realstart);
+       VectorCopy(tend, extendtraceinfo->realend);
+       VectorSubtract(extendtraceinfo->realend, extendtraceinfo->realstart, extendtraceinfo->realdelta);
+       VectorCopy(extendtraceinfo->realstart, extendtraceinfo->extendstart);
+       VectorCopy(extendtraceinfo->realend, extendtraceinfo->extendend);
+       VectorCopy(extendtraceinfo->realdelta, extendtraceinfo->extenddelta);
+       extendtraceinfo->reallength = VectorLength(extendtraceinfo->realdelta);
+       extendtraceinfo->extendlength = extendtraceinfo->reallength;
+       extendtraceinfo->scaletoextend = 1.0f;
+       extendtraceinfo->extend = textend;
+
+       // make the trace longer according to the extend parameter
+       if (extendtraceinfo->reallength && extendtraceinfo->extend)
+       {
+               extendtraceinfo->extendlength = extendtraceinfo->reallength + extendtraceinfo->extend;
+               extendtraceinfo->scaletoextend = extendtraceinfo->extendlength / extendtraceinfo->reallength;
+               VectorMA(extendtraceinfo->realstart, extendtraceinfo->scaletoextend, extendtraceinfo->realdelta, extendtraceinfo->extendend);
+               VectorSubtract(extendtraceinfo->extendend, extendtraceinfo->extendstart, extendtraceinfo->extenddelta);
+       }
+}
+
+static void Collision_ClipExtendFinish(extendtraceinfo_t *extendtraceinfo)
+{
+       trace_t *trace = extendtraceinfo->trace;
+
+       if (trace->fraction != 1.0f)
+       {
+               // undo the extended trace length
+               trace->fraction *= extendtraceinfo->scaletoextend;
+
+               // 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
+               if (trace->fraction > 1.0f)
+               {
+                       // note that ent may refer to either startsolid or fraction<1, we can't restore the startsolid ent unfortunately
+                       trace->ent = NULL;
+                       trace->hitq3surfaceflags = 0;
+                       trace->hitsupercontents = 0;
+                       trace->hittexture = NULL;
+                       VectorClear(trace->plane.normal);
+                       trace->plane.dist = 0.0f;
+               }
+       }
+
+       // clamp things
+       trace->fraction = bound(0, trace->fraction, 1);
+
+       // calculate the end position
+       VectorMA(extendtraceinfo->realstart, trace->fraction, extendtraceinfo->realdelta, trace->endpos);
+}
+
+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, int skipsupercontentsmask, int skipmaterialflagsmask, float extend)
+{
+       vec3_t starttransformed, endtransformed;
+       extendtraceinfo_t extendtraceinfo;
+       Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
+
+       Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
+       Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
 #if COLLISIONPARANOID >= 3
-       Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", start[0], start[1], start[2], starttransformed[0], starttransformed[1], starttransformed[2], end[0], end[1], end[2], endtransformed[0], endtransformed[1], endtransformed[2]);
+       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]);
 #endif
 
        if (model && model->TraceBox)
-               model->TraceBox(model, bound(0, frame, (model->numframes - 1)), trace, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask);
-       else
-               Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
-       trace->fraction = bound(0, trace->fraction, 1);
-       trace->realfraction = bound(0, trace->realfraction, 1);
+       {
+               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]))
+               {
+                       // we get here if TraceBrush exists, AND we have a rotation component (SOLID_BSP case)
+                       // using starttransformed, endtransformed is WRONG in this case!
+                       // should rather build a brush and trace using it
+                       colboxbrushf_t thisbrush_start, thisbrush_end;
+                       Collision_BrushForBox(&thisbrush_start, mins, maxs, 0, 0, NULL);
+                       Collision_BrushForBox(&thisbrush_end, mins, maxs, 0, 0, NULL);
+                       Collision_TranslateBrush(extendtraceinfo.extendstart, &thisbrush_start.brush);
+                       Collision_TranslateBrush(extendtraceinfo.extendend, &thisbrush_end.brush);
+                       Collision_TransformBrush(inversematrix, &thisbrush_start.brush);
+                       Collision_TransformBrush(inversematrix, &thisbrush_end.brush);
+                       //Collision_TranslateBrush(starttransformed, &thisbrush_start.brush);
+                       //Collision_TranslateBrush(endtransformed, &thisbrush_end.brush);
+                       model->TraceBrush(model, frameblend, skeleton, trace, &thisbrush_start.brush, &thisbrush_end.brush, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+               }
+               else // this is only approximate if rotated, quite useless
+                       model->TraceBox(model, frameblend, skeleton, trace, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       }
+       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
+               Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask, bodysupercontents, 0, NULL);
+
+       Collision_ClipExtendFinish(&extendtraceinfo);
 
-       VectorLerp(start, trace->fraction, end, trace->endpos);
        // transform plane
        // NOTE: this relies on plane.dist being directly after plane.normal
-       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
+       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal_and_dist);
 }
 
-void Collision_ClipToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t mins, const vec3_t maxs, const vec3_t end, int hitsupercontents)
+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 hitsupercontentsmask, int skipsupercontentsmask, int skipmaterialflagsmask, float extend)
 {
-       memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
+       extendtraceinfo_t extendtraceinfo;
+       Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
+       // ->TraceBox: TraceBrush not needed here, as worldmodel is never rotated
        if (model && model->TraceBox)
-               model->TraceBox(model, 0, trace, start, mins, maxs, end, hitsupercontents);
-       trace->fraction = bound(0, trace->fraction, 1);
-       trace->realfraction = bound(0, trace->realfraction, 1);
-       VectorLerp(start, trace->fraction, end, trace->endpos);
+               model->TraceBox(model, NULL, NULL, trace, extendtraceinfo.extendstart, mins, maxs, extendtraceinfo.extendend, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       Collision_ClipExtendFinish(&extendtraceinfo);
 }
 
-void Collision_ClipLineToGenericEntity(trace_t *trace, dp_model_t *model, int frame, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, const vec3_t end, int hitsupercontentsmask)
+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, int skipsupercontentsmask, int skipmaterialflagsmask, float extend, qboolean hitsurfaces)
 {
-       float starttransformed[3], endtransformed[3];
-
-       memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
-       VectorCopy(end, trace->endpos);
+       vec3_t starttransformed, endtransformed;
+       extendtraceinfo_t extendtraceinfo;
+       Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
 
-       Matrix4x4_Transform(inversematrix, start, starttransformed);
-       Matrix4x4_Transform(inversematrix, end, endtransformed);
+       Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
+       Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
 #if COLLISIONPARANOID >= 3
-       Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", start[0], start[1], start[2], starttransformed[0], starttransformed[1], starttransformed[2], end[0], end[1], end[2], endtransformed[0], endtransformed[1], endtransformed[2]);
+       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]);
 #endif
 
-       if (model && model->TraceLine)
-               model->TraceLine(model, bound(0, frame, (model->numframes - 1)), trace, starttransformed, endtransformed, hitsupercontentsmask);
+       if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
+               model->TraceLineAgainstSurfaces(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       else if (model && model->TraceLine)
+               model->TraceLine(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
        else
-               Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, vec3_origin, vec3_origin, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
-       trace->fraction = bound(0, trace->fraction, 1);
-       trace->realfraction = bound(0, trace->realfraction, 1);
+               Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, vec3_origin, vec3_origin, endtransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask, bodysupercontents, 0, NULL);
+
+       Collision_ClipExtendFinish(&extendtraceinfo);
 
-       VectorLerp(start, trace->fraction, end, trace->endpos);
        // transform plane
        // NOTE: this relies on plane.dist being directly after plane.normal
-       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
+       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal_and_dist);
 }
 
-void Collision_ClipLineToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t end, int hitsupercontents)
+void Collision_ClipLineToWorld(trace_t *trace, dp_model_t *model, const vec3_t tstart, const vec3_t tend, int hitsupercontentsmask, int skipsupercontentsmask, int skipmaterialflagsmask, float extend, qboolean hitsurfaces)
 {
-       memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
-       if (model && model->TraceLine)
-               model->TraceLine(model, 0, trace, start, end, hitsupercontents);
-       trace->fraction = bound(0, trace->fraction, 1);
-       trace->realfraction = bound(0, trace->realfraction, 1);
-       VectorLerp(start, trace->fraction, end, trace->endpos);
+       extendtraceinfo_t extendtraceinfo;
+       Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
+
+       if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
+               model->TraceLineAgainstSurfaces(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+       else if (model && model->TraceLine)
+               model->TraceLine(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
+
+       Collision_ClipExtendFinish(&extendtraceinfo);
 }
 
-void Collision_ClipPointToGenericEntity(trace_t *trace, dp_model_t *model, int frame, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, int hitsupercontentsmask)
+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, int skipsupercontentsmask, int skipmaterialflagsmask)
 {
        float starttransformed[3];
-
        memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
-       VectorCopy(start, trace->endpos);
+       trace->fraction = 1;
 
        Matrix4x4_Transform(inversematrix, start, starttransformed);
 #if COLLISIONPARANOID >= 3
@@ -1621,21 +1892,22 @@ void Collision_ClipPointToGenericEntity(trace_t *trace, dp_model_t *model, int f
 #endif
 
        if (model && model->TracePoint)
-               model->TracePoint(model, bound(0, frame, (model->numframes - 1)), trace, starttransformed, hitsupercontentsmask);
+               model->TracePoint(model, NULL, NULL, trace, starttransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
        else
-               Collision_ClipTrace_Point(trace, bodymins, bodymaxs, starttransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
+               Collision_ClipTrace_Point(trace, bodymins, bodymaxs, starttransformed, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask, bodysupercontents, 0, NULL);
 
+       VectorCopy(start, trace->endpos);
        // transform plane
        // NOTE: this relies on plane.dist being directly after plane.normal
-       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
+       Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal_and_dist);
 }
 
-void Collision_ClipPointToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, int hitsupercontents)
+void Collision_ClipPointToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, int hitsupercontentsmask, int skipsupercontentsmask, int skipmaterialflagsmask)
 {
        memset(trace, 0, sizeof(*trace));
-       trace->fraction = trace->realfraction = 1;
+       trace->fraction = 1;
        if (model && model->TracePoint)
-               model->TracePoint(model, 0, trace, start, hitsupercontents);
+               model->TracePoint(model, NULL, NULL, trace, start, hitsupercontentsmask, skipsupercontentsmask, skipmaterialflagsmask);
        VectorCopy(start, trace->endpos);
 }
 
@@ -1649,8 +1921,13 @@ void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *tou
                if (isbmodel)
                        cliptrace->bmodelstartsolid = true;
                cliptrace->startsolid = true;
-               if (cliptrace->realfraction == 1)
+               if (cliptrace->fraction == 1)
                        cliptrace->ent = touch;
+               if (cliptrace->startdepth > trace->startdepth)
+               {
+                       cliptrace->startdepth = trace->startdepth;
+                       VectorCopy(trace->startdepthnormal, cliptrace->startdepthnormal);
+               }
        }
        // don't set this except on the world, because it can easily confuse
        // monsters underwater if there's a bmodel involved in the trace
@@ -1659,10 +1936,9 @@ void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *tou
        //      cliptrace->inopen = true;
        if (trace->inwater)
                cliptrace->inwater = true;
-       if ((trace->realfraction <= cliptrace->realfraction) && (VectorLength2(trace->plane.normal) > 0))
+       if ((trace->fraction < cliptrace->fraction) && (VectorLength2(trace->plane.normal) > 0))
        {
                cliptrace->fraction = trace->fraction;
-               cliptrace->realfraction = trace->realfraction;
                VectorCopy(trace->endpos, cliptrace->endpos);
                cliptrace->plane = trace->plane;
                cliptrace->ent = touch;
@@ -1672,22 +1948,3 @@ void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *tou
        }
        cliptrace->startsupercontents |= trace->startsupercontents;
 }
-
-void Collision_ShortenTrace(trace_t *trace, float shorten_factor, const vec3_t end)
-{
-       // now undo our moving end 1 qu farther...
-       trace->fraction = bound(trace->fraction, trace->fraction / shorten_factor - 1e-6, 1); // we subtract 1e-6 to guard for roundoff errors
-       trace->realfraction = bound(trace->realfraction, trace->realfraction / shorten_factor - 1e-6, 1); // we subtract 1e-6 to guard for roundoff errors
-       if(trace->fraction >= 1) // trace would NOT hit if not expanded!
-       {
-               trace->fraction = 1;
-               trace->realfraction = 1;
-               VectorCopy(end, trace->endpos);
-               memset(&trace->plane, 0, sizeof(trace->plane));
-               trace->ent = NULL;
-               trace->hitsupercontentsmask = 0;
-               trace->hitsupercontents = 0;
-               trace->hitq3surfaceflags = 0;
-               trace->hittexture = NULL;
-       }
-}