public Color Trace(Ray ray, TraceData traceData)
{
RaycastHit forwardHit;
Color color;
traceData.Counters.Raycasts++;
if (Physics.Raycast(ray, out forwardHit))
{
if (traceData.PenetrationStack.Count != 0)
{
Vector3 pushedOutOrigin = forwardHit.point + forwardHit.normal * PushOutMagnitude;
Ray backwardRay = new Ray(pushedOutOrigin, -ray.direction);
if (TraceBackward(ray, backwardRay, forwardHit.distance, traceData, out color))
{
return(color);
}
}
color = GetColor(ray, forwardHit, traceData);
traceData.AddHistoryItem(ray, forwardHit, color);
return(color);
}
else
{
if (traceData.PenetrationStack.Count != 0)
{
var soughtCollider = traceData.PenetrationStack.Peek().collider;
var bounds = soughtCollider.bounds;
Vector3 extents = bounds.extents;
float boundingSphereRadius = extents.magnitude;
Vector3 vToBbCenter = bounds.center - ray.origin;
float projLen = Vector3.Dot(vToBbCenter, ray.direction);
Vector3 pushedOutOrigin = ray.origin + ray.direction * (projLen + boundingSphereRadius + PushOutMagnitude);
Ray backwardRay = new Ray(pushedOutOrigin, -ray.direction);
if (TraceBackward(ray, backwardRay, Vector3.Distance(ray.origin, pushedOutOrigin), traceData, out color))
{
return(color);
}
}
traceData.AddHistoryItem(ray, null, traceData.BackgroundColor);
return(traceData.BackgroundColor);
}
}
private bool TraceBackward(Ray forwardRay, Ray backwardRay, float maxDistance, TraceData traceData, out Color color)
{
var soughtCollider = traceData.PenetrationStack.Peek().collider;
traceData.Counters.Backtraces++;
/* Sometimes, due to imprecision of calculations,
* maxDistance is less than or equal to zero.
* We can fix this issue by setting it to some small value,
* it will not cause any error since origin point and
* ray direction are fine. */
if (maxDistance < MinRaycastDistance)
{
maxDistance = MinRaycastDistance;
}
var hits = Physics.RaycastAll(backwardRay, maxDistance)
.OrderByDescending(h => h.distance)
.Where(
h => h.collider == soughtCollider &&
h.distance < maxDistance // TODO: necessary? We already requested hits not farther than maxDistance. Test it.
)
.ToArray();
if (hits.Length != 0)
{
RaycastHit backwardHit = hits [0];
backwardHit.distance = maxDistance - backwardHit.distance;
color = GetColor(forwardRay, backwardHit, traceData);
traceData.AddHistoryItem(forwardRay, backwardHit, color);
return(true);
}
else
{
color = default(Color);
return(false);
}
}