Hit IShape.Intersect(Ray ray)
{
(double tmin, double tmax) = Box.Intersect(ray);
double step = 1.0 / 512;
double start = Math.Max(step, tmin);
int sign = -1;
for (double t = start; t <= tmax; t += step)
{
Vector p = ray.Position(t);
int s = Sign(p);
if (s == 0 || (sign >= 0 && s != sign))
{
t -= step;
step /= 64;
t += step;
for (int i = 0; i < 64; i++)
{
if (Sign(ray.Position(t)) == 0)
{
return(new Hit(this, t - step, null));
}
t += step;
}
}
sign = s;
}
return(Hit.NoHit);
}
internal Hit Intersect(Ray r)
{
(double tmin, double tmax) = Box.Intersect(r);
if (tmax < tmin || tmax <= 0)
{
return(Hit.NoHit);
}
return(Root.Intersect(r, tmin, tmax));
}
Hit IShape.Intersect(Ray ray)
{
double epsilon = 0.00001;
double start = 0.0001;
double jumpSize = 0.001;
Box box = BoundingBox();
(double t1, double t2) = box.Intersect(ray);
if (t2 < t1 || t2 < 0)
{
return(Hit.NoHit);
}
double t = Math.Max(start, t1);
bool jump = true;
for (int i = 0; i < 1000; i++)
{
var d = Evaluate(ray.Position(t));
if (jump && d < 0)
{
t -= jumpSize;
jump = false;
continue;
}
if (d < epsilon)
{
return(new Hit(this, t, null));
}
if (jump && d < jumpSize)
{
d = jumpSize;
}
t += d;
if (t > t2)
{
return(Hit.NoHit);
}
}
return(Hit.NoHit);
}