private static void CM_TestBoxInBrush(Vector3 p1, ref TraceT trace, BSPBrush brush)
{
BSPBrushSide[] sides = brush.Sides;
BSPPlane plane;
float dist, d1;
for (int i = 0; i < sides.Length; i++)
{
plane = sides[i].Plane;
dist = Vector3.Dot(trace_offsets[plane.Signbits], plane.normal);
dist = plane.distance - dist;
d1 = Vector3.Dot(p1, plane.normal) - dist;
//completely in front of a face, no intersection
if (d1 > 0)
{
return;
}
}
trace.startsolid = trace.allsolid = true;
trace.fraction = 0;
trace.contents = brush.contents;
}
/// <summary>
/// Checks for intersection with a brush during a moving trace.
/// </summary>
/// <param name="p1">Trace start.</param>
/// <param name="p2">Trace end.</param>
/// <param name="trace">Data struct.</param>
/// <param name="brush">Brush to test against.</param>
private static void CM_ClipBoxToBrush(Vector3 p1, Vector3 p2, ref TraceT trace, BSPBrush brush)
{
int i;
BSPPlane plane;
BSPPlane clipplane = new BSPPlane(); //initialize this to keep c# happy...
float dist;
float enterfrac, leavefrac;
float d1, d2;
bool getout, startout;
bool hasclip = false;
bool haslead = false;
float f;
BSPBrushSide leadside = new BSPBrushSide(); //initialize this to keep c# happy...
BSPBrushSide[] sides;
if (brush.numsides == 0)
{
return;
}
sides = brush.Sides;
enterfrac = -1;
leavefrac = 1;
getout = false; //gets out of the brush
startout = false; //starts inside the brush
for (i = 0; i < brush.numsides; i++)
{
plane = sides[i].Plane; //we only need plane for each side
//get plane to bounds point distance
if (!trace_ispoint)
{
//bounding box trace
dist = Vector3.Dot(trace_offsets[plane.Signbits], plane.normal);
dist = plane.distance - dist;
}
else
{
//point trace
dist = plane.distance;
}
//get distances for start and end of the trace
d1 = Vector3.Dot(p1, plane.normal) - dist; //start
d2 = Vector3.Dot(p2, plane.normal) - dist; //end
if (d2 > 0)
{
getout = true; //endpoint is not in solid
}
if (d1 > 0)
{
startout = true; //starts outside
}
//if completely in front of a face, no intersection
if (d1 > 0 && d2 >= d1)
{
return; //a single face plane that is not crossed while tracing means that we never hit that brush
}
//?
if (d1 <= 0 && d2 <= 0)
{
continue;
}
//crosses face
if (d1 > d2)
{
//enter
f = (d1 - DIST_EPSILON) / (d1 - d2); //fraction of the distance covered before hitting a side
if (f > enterfrac)
{
enterfrac = f;
clipplane = plane;
hasclip = true; //plane clips the trace
leadside = sides[i];
haslead = true; //could be combined with hasclip? writes flags for the collided face
}
}
else
{
//leave
f = (d1 + DIST_EPSILON) / (d1 - d2);
if (f < leavefrac)
{
leavefrac = f;
}
}
}
//startout wasn't true for any face
if (!startout)
{
//original point was inside brush
trace.startsolid = true;
if (!getout)
{
trace.allsolid = true;
//map_allsolid_bug
trace.fraction = 0;
trace.contents = brush.contents;
}
return;
}
//after testing all faces we need to see which test went further
if (enterfrac < leavefrac)
{
//only write the test if the brush was closer than any brushes hit before
if (enterfrac > -1 && enterfrac < trace.fraction)
{
if (enterfrac < 0)
{
enterfrac = 0;
}
trace.fraction = enterfrac;
if (hasclip)
{
trace.plane = clipplane;
}
if (haslead)
{
if (leadside.HasTexInfo)
{
trace.surface = leadside.TexInfo.Surface;
}
}
trace.contents = brush.contents;
}
}
}
