public TransparentMaterial(Vector3 Albedo, Medium Medium = null)
{
Properties.Add("albedo", new MaterialConstantNode(Albedo));
this.Medium = Medium;
}
public TransparentMaterial(MaterialNode Albedo, Medium Medium = null)
{
Properties.Add("albedo", Albedo);
this.Medium = Medium;
}
private Vector3 Trace(Ray Ray)
{
Medium CurrentMedium = null;
LobeType SampledLobe = LobeType.SpecularReflection;
Vector3 FinalColor = Vector3.Zero;
Vector3 Throughput = Vector3.One;
for (int Bounce = 0; Bounce < MaxBounces; Bounce++)
{
//Raycast to nearest geometry, if any
World.Raycast(Ray, out Shape Shape, out Vector3 Hit, out Vector3 Normal, out Vector2 UV);
//Return skybox color if nothing hit
if (Shape == null)
{
if (SkyBox == null)
{
FinalColor += Throughput * Vector3.One;
}
else
{
FinalColor += Throughput * SkyBox.GetColorAtUV(new Vector2(1 - (1.0 + Math.Atan2(Ray.Direction.Z, Ray.Direction.X) / MathHelper.Pi) * 0.5, 1 - Math.Acos(Ray.Direction.Y) / MathHelper.Pi));
}
break;
}
//Volumetrics, slightly borken
bool Scattered = false;
if (CurrentMedium != null)
{
double MaxDistance = (Hit - Ray.Origin).Length();
double Distance = CurrentMedium.SampleDistance(MaxDistance);
Vector3 Transmission = CurrentMedium.Transmission(Distance);
Throughput *= Transmission;
if (Distance < MaxDistance)
{
Scattered = true;
Ray.Direction = CurrentMedium.SampleDirection(Ray.Direction);
Ray.Origin = Hit + Ray.Direction * 0.001;
}
}
//If no scattering event happened, do normal path tracing
if (!Scattered)
{
//Area lights
if (Shape.Material.HasProperty("emission"))
{
//Don't add emission to diffuse term if NEE is on, we already sample it directly
if (SampledLobe == LobeType.SpecularReflection || !NEE)
{
FinalColor += Throughput * Shape.Material.GetProperty("emission", UV).Color;
}
break;
}
Vector3 ViewDirection = Vector3.Normalize(Ray.Origin - Hit);
//Sample BSDF
Shape.Material.Sample(ViewDirection, Normal, UV, out Vector3 SampleDirection, out SampledLobe);
Shape.Material.PDF(ViewDirection, Normal, UV, SampleDirection, SampledLobe, out double PDF);
Shape.Material.Evaluate(ViewDirection, Normal, UV, SampleDirection, SampledLobe, out Vector3 Attenuation);
//Sample direct lighting
if (NEE)
{
FinalColor += Throughput * SampleLight(Shape, Hit, ViewDirection, Normal, UV, SampleDirection, SampledLobe, Attenuation);
}
//Accumulate BSDF attenuation
Throughput *= Attenuation / PDF;
//If we entered a medium, update current medium
if (SampledLobe == LobeType.SpecularTransmission || SampledLobe == LobeType.DiffuseTransmission)
{
CurrentMedium = Shape.Material.Medium;
}
//Set new ray direction to sampled ray
Ray.Origin = Hit + SampleDirection * 0.001;
Ray.Direction = SampleDirection;
}
//Russian roulette
if (Bounce >= MinBounces)
{
double Prob = Math.Max(Throughput.X, Math.Max(Throughput.Y, Throughput.Z));
if (Util.Random.NextDouble() > Prob)
{
break;
}
Throughput *= 1.0 / Prob;
}
}
return(FinalColor);
}
public GlassMaterial(MaterialNode Albedo, MaterialNode RefractiveIndex, MaterialNode Roughness, MaterialNode Normal, Medium Medium = null)
{
Properties.Add("albedo", Albedo);
Properties.Add("ior", RefractiveIndex);
Properties.Add("roughness", Roughness);
if (Normal != null)
{
Properties.Add("normal", Normal);
}
this.Medium = Medium;
}
public GlassMaterial(Vector3 Albedo, double RefractiveIndex, double Roughness, Medium Medium = null)
{
Properties.Add("albedo", new MaterialConstantNode(Albedo));
Properties.Add("ior", new MaterialConstantNode(RefractiveIndex));
Properties.Add("roughness", new MaterialConstantNode(Roughness));
this.Medium = Medium;
}
public Material(Medium Medium = null)
{
this.Medium = Medium;
this.Properties = new Dictionary <string, MaterialNode>();
}
