]> de.git.xonotic.org Git - xonotic/darkplaces.git/blobdiff - collision.c
fix glDrawRangeElements issue with mesa
[xonotic/darkplaces.git] / collision.c
index 87c10b739b9d50ce6a1522b0a702a3776b98fbce..31498891d27c96916faedffc83f508a6e0e9847e 100644 (file)
@@ -561,11 +561,13 @@ colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, i
 void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 {
        int nplane, nplane2, hitq3surfaceflags = 0;
-       float enterfrac = -1, leavefrac = 1, d1, d2, f, imove, newimpactnormal[3], enterfrac2 = -1;
+       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(newimpactnormal);
+       VectorClear(newimpactplane.normal);
+       newimpactplane.dist = 0;
 
        for (nplane = 0;nplane < thatbrush_start->numplanes + thisbrush_start->numplanes;nplane++)
        {
@@ -587,8 +589,10 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
                                        Con_Printf("startplane->dist %f != calculated %f (thisbrush_start)\n", startplane->dist, f);
                        }
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - furthestplanedist_float(startplane->normal, thatbrush_start->points, thatbrush_start->numpoints) - collision_startnudge.value;
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - furthestplanedist_float(endplane->normal, thatbrush_end->points, thatbrush_end->numpoints) - collision_endnudge.value;
+                       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;
                }
                else
                {
@@ -606,21 +610,25 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                if (fabs(f - startplane->dist) > COLLISION_PLANE_DIST_EPSILON)
                                        Con_Printf("startplane->dist %f != calculated %f (thatbrush_start)\n", startplane->dist, f);
                        }
-                       d1 = nearestplanedist_float(startplane->normal, thisbrush_start->points, thisbrush_start->numpoints) - startplane->dist - collision_startnudge.value;
-                       d2 = nearestplanedist_float(endplane->normal, thisbrush_end->points, thisbrush_end->numpoints) - endplane->dist - collision_endnudge.value;
+                       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;
                }
                //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)
                {
                        // moving into brush
-                       if (d2 > 0)
+                       if (d2 >= collision_enternudge.value)
                                return;
                        if (d1 > 0)
                        {
                                // enter
                                imove = 1 / (d1 - d2);
                                f = (d1 - collision_enternudge.value) * imove;
+                               if (f < 0)
+                                       f = 0;
                                // check if this will reduce the collision time range
                                if (enterfrac < f)
                                {
@@ -636,8 +644,12 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                                                return;
                                        // calculate the nudged fraction and impact normal we'll
                                        // need if we accept this collision later
-                                       enterfrac2 = f - collision_impactnudge.value * imove;
-                                       VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                                       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;
                                }
@@ -652,6 +664,8 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
                        {
                                // leave
                                f = (d1 + collision_leavenudge.value) / (d1 - d2);
+                               if (f > 1)
+                                       f = 1;
                                // check if this will reduce the collision time range
                                if (leavefrac > f)
                                {
@@ -668,31 +682,34 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
        // at this point we know the trace overlaps the brush because it was not
        // rejected at any point in the loop above
 
-       // see if this brush can block the trace or not according to contents
-       if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+       // see if the trace started outside the brush or not
+       if (enterfrac > -1)
        {
-               if (enterfrac == -1)
+               // started outside, and overlaps, therefore there is a collision here
+               // store out the impact information
+               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
                {
-                       trace->startsupercontents |= thatbrush_start->supercontents;
-                       trace->startsolid = true;
-                       if (leavefrac < 1)
-                               trace->allsolid = true;
+                       trace->hitsupercontents = thatbrush_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;
                }
-               // store out the impact information
-               trace->hitsupercontents = thatbrush_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;
-               VectorCopy(newimpactnormal, trace->plane.normal);
        }
        else
        {
-               // this brush can not block the trace, but it can update start contents
-               if (enterfrac == -1)
-                       trace->startsupercontents |= thatbrush_start->supercontents;
+               // started inside, update startsolid and friends
+               trace->startsupercontents |= thatbrush_start->supercontents;
+               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               {
+                       trace->startsolid = true;
+                       if (leavefrac < 1)
+                               trace->allsolid = true;
+                       trace->plane = newimpactplane;
+               }
        }
 }
 
@@ -700,11 +717,13 @@ void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *thisbrush
 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *thatbrush_start, const colbrushf_t *thatbrush_end)
 {
        int nplane, hitq3surfaceflags = 0;
-       float enterfrac = -1, leavefrac = 1, d1, d2, f, imove, newimpactnormal[3], enterfrac2 = -1;
+       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(newimpactnormal);
+       VectorClear(newimpactplane.normal);
+       newimpactplane.dist = 0;
 
        for (nplane = 0;nplane < thatbrush_start->numplanes;nplane++)
        {
@@ -731,13 +750,15 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
                if (d1 > d2)
                {
                        // moving into brush
-                       if (d2 > 0)
+                       if (d2 >= collision_enternudge.value)
                                return;
                        if (d1 > 0)
                        {
                                // enter
                                imove = 1 / (d1 - d2);
                                f = (d1 - collision_enternudge.value) * imove;
+                               if (f < 0)
+                                       f = 0;
                                // check if this will reduce the collision time range
                                if (enterfrac < f)
                                {
@@ -753,8 +774,12 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
                                                return;
                                        // calculate the nudged fraction and impact normal we'll
                                        // need if we accept this collision later
-                                       enterfrac2 = f - collision_impactnudge.value * imove;
-                                       VectorLerp(startplane->normal, enterfrac, endplane->normal, newimpactnormal);
+                                       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;
                                }
@@ -785,42 +810,54 @@ void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const
        // at this point we know the trace overlaps the brush because it was not
        // rejected at any point in the loop above
 
-       // see if this brush can block the trace or not according to contents
-       if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+       // see if the trace started outside the brush or not
+       if (enterfrac > -1)
        {
-               if (enterfrac == -1)
+               // started outside, and overlaps, therefore there is a collision here
+               // store out the impact information
+               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
                {
-                       trace->startsupercontents |= thatbrush_start->supercontents;
-                       trace->startsolid = true;
-                       if (leavefrac < 1)
-                               trace->allsolid = true;
+                       trace->hitsupercontents = thatbrush_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;
                }
-               // store out the impact information
-               trace->hitsupercontents = thatbrush_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;
-               VectorCopy(newimpactnormal, trace->plane.normal);
        }
        else
        {
-               // this brush can not block the trace, but it can update start contents
-               if (enterfrac == -1)
-                       trace->startsupercontents |= thatbrush_start->supercontents;
+               // started inside, update startsolid and friends
+               trace->startsupercontents |= thatbrush_start->supercontents;
+               if (trace->hitsupercontentsmask & thatbrush_start->supercontents)
+               {
+                       trace->startsolid = true;
+                       if (leavefrac < 1)
+                               trace->allsolid = true;
+                       trace->plane = newimpactplane;
+               }
        }
 }
 
-void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
+qboolean Collision_PointInsideBrushFloat(const vec3_t point, const colbrushf_t *brush)
 {
        int nplane;
        const colplanef_t *plane;
 
-       for (nplane = 0, plane = thatbrush->planes;nplane < thatbrush->numplanes;nplane++, plane++)
+       if (!BoxesOverlap(point, point, brush->mins, brush->maxs))
+               return false;
+       for (nplane = 0, plane = brush->planes;nplane < brush->numplanes;nplane++, plane++)
                if (DotProduct(plane->normal, point) > plane->dist)
-                       return;
+                       return false;
+       return true;
+}
+
+void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
+{
+       if (!Collision_PointInsideBrushFloat(point, thatbrush))
+               return;
 
        trace->startsupercontents |= thatbrush->supercontents;
        if (trace->hitsupercontentsmask & thatbrush->supercontents)
@@ -864,7 +901,7 @@ void Collision_TraceBrushPolygonFloat(trace_t *trace, const colbrushf_t *thisbru
        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 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, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 {
        int i;
        polyf_brush.numpoints = 3;
@@ -877,22 +914,44 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
                polyf_brush.planes[i].q3surfaceflags = q3surfaceflags;
                polyf_brush.planes[i].texture = texture;
        }
-       for (i = 0;i < numtriangles;i++, element3i += 3)
+       if(stride)
        {
-               if (segmentmaxs[0] >= min(vertex3f[element3i[0]*3+0], min(vertex3f[element3i[1]*3+0], vertex3f[element3i[2]*3+0]))
-                && segmentmins[0] <= max(vertex3f[element3i[0]*3+0], max(vertex3f[element3i[1]*3+0], vertex3f[element3i[2]*3+0]))
-                && segmentmaxs[1] >= min(vertex3f[element3i[0]*3+1], min(vertex3f[element3i[1]*3+1], vertex3f[element3i[2]*3+1]))
-                && segmentmins[1] <= max(vertex3f[element3i[0]*3+1], max(vertex3f[element3i[1]*3+1], vertex3f[element3i[2]*3+1]))
-                && segmentmaxs[2] >= min(vertex3f[element3i[0]*3+2], min(vertex3f[element3i[1]*3+2], vertex3f[element3i[2]*3+2]))
-                && segmentmins[2] <= max(vertex3f[element3i[0]*3+2], max(vertex3f[element3i[1]*3+2], vertex3f[element3i[2]*3+2])))
+               int k, cnt, tri;
+               cnt = (numtriangles + stride - 1) / stride;
+               for(i = 0; i < cnt; ++i)
                {
-                       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);
+                       if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
+                       {
+                               for(k = 0; k < stride; ++k)
+                               {
+                                       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);
+                               }
+                       }
+               }
+       }
+       else
+       {
+               for (i = 0;i < numtriangles;i++, element3i += 3)
+               {
+                       if (TriangleOverlapsBox(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);
+                       }
                }
        }
 }
@@ -916,13 +975,34 @@ void Collision_TraceLinePolygonFloat(trace_t *trace, const vec3_t linestart, con
        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 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, texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 {
        int i;
 #if 1
        // FIXME: snap vertices?
-       for (i = 0;i < numtriangles;i++, element3i += 3)
-               Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3, supercontents, q3surfaceflags, texture);
+       if(stride)
+       {
+               int k, cnt, tri;
+               cnt = (numtriangles + stride - 1) / stride;
+               for(i = 0; i < cnt; ++i)
+               {
+                       if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
+                       {
+                               for(k = 0; k < stride; ++k)
+                               {
+                                       tri = i * stride + k;
+                                       if(tri >= numtriangles)
+                                               break;
+                                       Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[tri * 3 + 0] * 3, vertex3f + element3i[tri * 3 + 1] * 3, vertex3f + element3i[tri * 3 + 2] * 3, supercontents, q3surfaceflags, texture);
+                               }
+                       }
+               }
+       }
+       else
+       {
+               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;
@@ -937,12 +1017,7 @@ void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart
        }
        for (i = 0;i < numtriangles;i++, element3i += 3)
        {
-               if (segmentmaxs[0] >= min(vertex3f[element3i[0]*3+0], min(vertex3f[element3i[1]*3+0], vertex3f[element3i[2]*3+0]))
-                && segmentmins[0] <= max(vertex3f[element3i[0]*3+0], max(vertex3f[element3i[1]*3+0], vertex3f[element3i[2]*3+0]))
-                && segmentmaxs[1] >= min(vertex3f[element3i[0]*3+1], min(vertex3f[element3i[1]*3+1], vertex3f[element3i[2]*3+1]))
-                && segmentmins[1] <= max(vertex3f[element3i[0]*3+1], max(vertex3f[element3i[1]*3+1], vertex3f[element3i[2]*3+1]))
-                && segmentmaxs[2] >= min(vertex3f[element3i[0]*3+2], min(vertex3f[element3i[1]*3+2], vertex3f[element3i[2]*3+2]))
-                && segmentmins[2] <= max(vertex3f[element3i[0]*3+2], max(vertex3f[element3i[1]*3+2], vertex3f[element3i[2]*3+2])))
+               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);
@@ -1002,7 +1077,9 @@ void Collision_TraceBrushPolygonTransformFloat(trace_t *trace, const colbrushf_t
 
 
 #define MAX_BRUSHFORBOX 16
-static int brushforbox_index = 0;
+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];
@@ -1145,7 +1222,7 @@ float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double
        if (deviationdist > sphereradius*sphereradius)
                return 1; // miss (off to the side)
        // nudge back to find the correct impact distance
-       impactdist += deviationdist - sphereradius;
+       impactdist -= sphereradius - deviationdist/sphereradius;
        if (impactdist >= linelength)
                return 1; // miss (not close enough)
        if (impactdist < 0)
@@ -1452,3 +1529,95 @@ void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const co
        maxs[2] += 1;
 }
 
+//===========================================
+
+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)
+{
+       float starttransformed[3], endtransformed[3];
+
+       memset(trace, 0, sizeof(*trace));
+       trace->fraction = trace->realfraction = 1;
+       VectorCopy(end, trace->endpos);
+
+       Matrix4x4_Transform(inversematrix, start, starttransformed);
+       Matrix4x4_Transform(inversematrix, end, 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]);
+#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);
+
+       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);
+}
+
+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)
+{
+       memset(trace, 0, sizeof(*trace));
+       trace->fraction = trace->realfraction = 1;
+       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);
+}
+
+void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *touch, qboolean isbmodel)
+{
+       // take the 'best' answers from the new trace and combine with existing data
+       if (trace->allsolid)
+               cliptrace->allsolid = true;
+       if (trace->startsolid)
+       {
+               if (isbmodel)
+                       cliptrace->bmodelstartsolid = true;
+               cliptrace->startsolid = true;
+               if (cliptrace->realfraction == 1)
+                       cliptrace->ent = touch;
+       }
+       // don't set this except on the world, because it can easily confuse
+       // monsters underwater if there's a bmodel involved in the trace
+       // (inopen && inwater is how they check water visibility)
+       //if (trace->inopen)
+       //      cliptrace->inopen = true;
+       if (trace->inwater)
+               cliptrace->inwater = true;
+       if ((trace->realfraction <= cliptrace->realfraction) && (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;
+               cliptrace->hitsupercontents = trace->hitsupercontents;
+               cliptrace->hitq3surfaceflags = trace->hitq3surfaceflags;
+               cliptrace->hittexture = trace->hittexture;
+       }
+       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;
+       }
+}