]> de.git.xonotic.org Git - xonotic/darkplaces.git/blobdiff - collision.c
clarify a comment
[xonotic/darkplaces.git] / collision.c
index ed1fac4e586e1ef07f995eb6e7bb4c1c88c53d6d..ef237e92e6d7c61ad2e4961acb0aad57e091665b 100644 (file)
@@ -20,6 +20,9 @@ cvar_t collision_endposnudge = {0, "collision_endposnudge", "0", "workaround to
 #endif
 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_neighborsides = {0, "collision_triangle_neighborsides", "1", "override automatic side generation if triangle has neighbors with face planes that form a convex edge (perfect solution, but can not work for all edges)"};
+cvar_t collision_triangle_bevelsides = {0, "collision_triangle_bevelsides", "1", "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"};
 
 mempool_t *collision_mempool;
 
@@ -36,6 +39,9 @@ void Collision_Init (void)
 #endif
        Cvar_RegisterVariable(&collision_debug_tracelineasbox);
        Cvar_RegisterVariable(&collision_cache);
+//     Cvar_RegisterVariable(&collision_triangle_neighborsides);
+       Cvar_RegisterVariable(&collision_triangle_bevelsides);
+       Cvar_RegisterVariable(&collision_triangle_axialsides);
        collision_mempool = Mem_AllocPool("collision cache", 0, NULL);
        Collision_Cache_Init(collision_mempool);
 }
@@ -448,164 +454,98 @@ 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;
-                       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;
-                       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);
-#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_extra.integer)
-                       {
-                               // 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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_DPrintf("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_extra.integer)
        {
@@ -1085,7 +1025,7 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
                                        VectorCopy(vertex3f + element3i[tri * 3 + 2] * 3, points[2].v);
                                        Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
                                        Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
-                                       Collision_CalcPlanesForPolygonBrushFloat(&brush);
+                                       Collision_CalcPlanesForTriangleBrushFloat(&brush);
                                        //Collision_PrintBrushAsQHull(&brush, "brush");
                                        Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
                                }
@@ -1096,14 +1036,14 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
        {
                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, 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_CalcPlanesForPolygonBrushFloat(&brush);
+                               Collision_CalcPlanesForTriangleBrushFloat(&brush);
                                //Collision_PrintBrushAsQHull(&brush, "brush");
                                Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
                        }
@@ -1118,7 +1058,7 @@ void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *th
                        VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
                        Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
                        Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
-                       Collision_CalcPlanesForPolygonBrushFloat(&brush);
+                       Collision_CalcPlanesForTriangleBrushFloat(&brush);
                        //Collision_PrintBrushAsQHull(&brush, "brush");
                        Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
                }
@@ -1183,7 +1123,7 @@ void Collision_TraceBrushTriangleFloat(trace_t *trace, const colbrushf_t *thisbr
        VectorCopy(v2, points[2].v);
        Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
        Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
-       Collision_CalcPlanesForPolygonBrushFloat(&brush);
+       Collision_CalcPlanesForTriangleBrushFloat(&brush);
        //Collision_PrintBrushAsQHull(&brush, "brush");
        Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
 }
@@ -1256,7 +1196,7 @@ void Collision_BrushForBox(colboxbrushf_t *boxbrush, const vec3_t mins, const ve
 // 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);
@@ -1278,13 +1218,12 @@ 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)
@@ -1744,7 +1683,7 @@ static collision_cachedtrace_t *Collision_Cache_Lookup(dp_model_t *model, const
        collision_cachedtrace_parameters_t params;
        // all non-cached traces use the same index
        if (!collision_cache.integer)
-               r_refdef.stats.collisioncache_traced++;
+               r_refdef.stats[r_stat_photoncache_traced]++;
        else
        {
                // cached trace lookup
@@ -1789,12 +1728,12 @@ static collision_cachedtrace_t *Collision_Cache_Lookup(dp_model_t *model, const
                        )
                                continue;
                        // found a matching trace in the cache
-                       r_refdef.stats.collisioncache_cached++;
+                       r_refdef.stats[r_stat_photoncache_cached]++;
                        cached->valid = true;
                        collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
                        return cached;
                }
-               r_refdef.stats.collisioncache_traced++;
+               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)
@@ -2015,7 +1954,7 @@ 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->realfraction < cliptrace->realfraction) && (VectorLength2(trace->plane.normal) > 0))
        {
                cliptrace->fraction = trace->fraction;
                cliptrace->realfraction = trace->realfraction;