public override bool Scatter(Ray rIn, HitRecord rec, ref Vector3 attenuation, ref Ray scattered)
{
Vector3 outwardNormal = new Vector3();
Vector3 reflected = RTUtils.Reflect(rIn.Direction, rec.Normal);
double niOverNt;
attenuation = new Vector3(1, 1, 1); //衰减率
Vector3 refracted = new Vector3();
double reflect_prob;
double cosine;
if (Vector3.DotProduct(rIn.Direction, rec.Normal) > 0)
{
outwardNormal = rec.Normal * -1;
niOverNt = refIdx;
cosine = refIdx * Vector3.DotProduct(rIn.Direction, rec.Normal) / rIn.Direction.Length();
}
else
{
outwardNormal = rec.Normal;
niOverNt = 1.0 / refIdx;
cosine = -Vector3.DotProduct(rIn.Direction, rec.Normal) / rIn.Direction.Length();
}
if (RTUtils.Refract(rIn.Direction, outwardNormal, niOverNt, ref refracted))
{
reflect_prob = RTUtils.Schlick(cosine, refIdx);
}
else
{
scattered = new Ray(new Point3D(rec.P.X, rec.P.Y, rec.P.Z), reflected);
reflect_prob = 1.0;
}
if (RTUtils.rd.NextDouble() < reflect_prob)
{
scattered = new Ray(new Point3D(rec.P.X, rec.P.Y, rec.P.Z), reflected);
}
else
{
scattered = new Ray(new Point3D(rec.P.X, rec.P.Y, rec.P.Z), refracted);
}
return(true);
}
public virtual bool Hit(Ray r, double tMin, double tMax, ref HitRecord rec)
{
return(false);
}
public virtual bool Scatter(Ray rIn, HitRecord rec, ref Vector3 attenuation, ref Ray scattered)
{
return(false);
}
