public bool Scatter(Ray p_rayIn, HitRecord p_hitRecord, ref Color p_attenuation, ref Ray p_scatteredRay)
{
if (p_attenuation == null)
{
throw new ArgumentNullException(nameof(p_attenuation));
}
var reflected = Vec3.GetReflection(Vec3.GetUnitVector(p_rayIn.Direction), p_hitRecord.Normal);
p_scatteredRay = new Ray(p_hitRecord.Point, reflected + Roughness * Math.GetRandomPositionInUnitSphere(), p_rayIn.Time);
p_attenuation = Albedo;
return(Vec3.GetDotProduct(p_scatteredRay.Direction, p_hitRecord.Normal) > 0);
}
public bool Scatter(Ray p_rayIn, HitRecord p_hitRecord, ref Color p_attenuation, ref Ray p_scatteredRay)
{
if (p_attenuation == null)
{
throw new ArgumentNullException(nameof(p_attenuation));
}
var target = p_hitRecord.Point + p_hitRecord.Normal + Math.GetRandomPositionInUnitSphere();
p_scatteredRay = new Ray(p_hitRecord.Point, target - p_hitRecord.Point, p_rayIn.Time);
p_attenuation = Albedo.GetValue(p_hitRecord.U, p_hitRecord.V, p_hitRecord.Point);
return(true);
}
public bool Scatter(Ray p_rayIn, HitRecord p_hitRecord, ref Color p_attenuation, ref Ray p_scatteredRay)
{
if (p_attenuation == null)
{
throw new ArgumentNullException(nameof(p_attenuation));
}
var rng = new Random();
Vec3 outwardNormal;
var reflected = Vec3.GetReflection(p_rayIn.Direction, p_hitRecord.Normal);
var refracted = new Vec3(0);
double niOverNt;
p_attenuation = Color;
double cosine;
if (Vec3.GetDotProduct(p_rayIn.Direction, p_hitRecord.Normal) > 0)
{
outwardNormal = -p_hitRecord.Normal;
niOverNt = IndexOfRefraction;
cosine = IndexOfRefraction * Vec3.GetDotProduct(p_rayIn.Direction, p_hitRecord.Normal) /
p_rayIn.Direction.GetLength();
}
else
{
outwardNormal = p_hitRecord.Normal;
niOverNt = 1.0 / IndexOfRefraction;
cosine = -Vec3.GetDotProduct(p_rayIn.Direction, p_hitRecord.Normal) / p_rayIn.Direction.GetLength();
}
var reflectionProbability = Vec3.ShouldRefract(p_rayIn.Direction, outwardNormal, niOverNt, ref refracted) ? Math.SchlickApproximation(cosine, IndexOfRefraction) : 1.0d;
p_scatteredRay = rng.NextDouble() < reflectionProbability ? new Ray(p_hitRecord.Point, reflected, p_rayIn.Time) : new Ray(p_hitRecord.Point, refracted, p_rayIn.Time);
return(true);
}