public Vec3 GetColor(ShadeRec sr)
{
ShadeRec localSr = sr.Clone();
localSr.LocalHitPoint = MathUtils.TransformPoint(invMatrix, sr.LocalHitPoint);
return(texture.GetColor(localSr));
}
public bool Scatter(Ray ray, HitRecord record, ref Vector attenuation, ref Ray scattered)
{
var reflected = Reflect(ray.Direction.Normalize(), record.Normal);
scattered = new Ray(record.P, reflected + fuzz * MathHelper.RandUnitVector(record.Normal));
attenuation = albedo.GetColor(record.U, record.V, record.P);
return(scattered.Direction.Dot(record.Normal) > 0);
}
public bool Scatter(Ray ray, HitRecord record, ref Vector attenuation, ref Ray scattered)
{
var reflected = record.Normal + record.P + MathHelper.RandUnitVector(record.Normal);
attenuation = albedo.GetColor(record.U, record.V, record.P);
scattered = new Ray(record.P, reflected - record.P);
return(true);
}
public Vector GetColor(float u, float v, Vector p)
{
var sin = Math.Sin(10 * p.X) * Math.Sin(10 * p.Y) * Math.Sin(10 * p.Z);
return(sin < 0
? odd.GetColor(u, v, p)
: even.GetColor(u, v, p));
}
public bool Scatter(Ray ray, HitRecord record, ref Vector attenuation, ref Ray scattered)
{
attenuation = albedo.GetColor(record.U, record.V, record.P);
var refracted = Vector.Zero;
Vector outwardNormal;
float newRefractivity;
float cosin;
float possible;
var reflected = Reflect(ray.Direction, record.Normal);
if (ray.Direction.Dot(record.Normal) > 0f)
{
outwardNormal = record.Normal.Negative();
newRefractivity = refractivity;
cosin = ray.Direction.Normalize().Dot(record.Normal);
}
else
{
outwardNormal = record.Normal;
newRefractivity = 1f / refractivity;
cosin = -ray.Direction.Normalize().Dot(record.Normal);
}
if (Refract(ray.Direction, outwardNormal, newRefractivity, ref refracted))
{
possible = SchlickEquation(cosin, newRefractivity);
}
else
{
scattered = new Ray(record.P, reflected);
possible = 1f;
}
// reflection or refraction
if (MathHelper.Randf() < possible)
{
scattered = new Ray(record.P, reflected);
}
else
{
scattered = new Ray(record.P, refracted);
}
return(true);
}
public override Vec3 F(ShadeRec sr, Vec3 wi, Vec3 wo)
{
return(kd * cd.GetColor(sr) * MathUtils.InvPI);
}
public FloatColor GetColor(Vector2 uv) => Texture.GetColor(uv, Scale, Offset);
