public DiskLight(Transformation objectToWorld, float radius = 1, SampledSpectrum spectrum = null)
: base(objectToWorld, spectrum)
{
_radius = radius;
_normal = ObjectToWorld.TransformNormal(new Vector3(0, -1, 0)).Normalized();
NSamples = (uint)Math.Max(1, _radius / 4f);
}
public override Ray GenerateRay(Sample sample)
{
var ray = new Ray(new Vector3(_screenLeft + sample.X, _screenUp - sample.Y, FocalDistance).Normalized(),
Vector3.Zero);
return(ObjectToWorld.TransformRay(ray));
}
public void OnCreate(ECSWorld world)
{
var fragShader = Asset.Load <ShaderAsset>("mesh_instanced_default.frag");
var vertShader = Asset.Load <ShaderAsset>("mesh_instanced_default.vert");
var shader = new ShaderPipeline(fragShader, vertShader, ShaderType.Instanced);
defaultShader = shader.ShaderPair;
defaultMaterial = new Material(GraphicsContext.graphicsDevice,
GraphicsContext.uniform0, defaultShader);
defaultMaterial.wireframe = true;
instanceMatrix = new DeviceBuffer(GraphicsContext.graphicsDevice, (ulong)Unsafe.SizeOf <ObjectToWorld>(),
BufferUsageFlags.VertexBuffer, BufferMemoryUsageHint.Dynamic);
var matrix = mat4.Identity;
var normalMatrix = new mat3(matrix);
ObjectToWorld matrices = new ObjectToWorld()
{
model = matrix,
normal = normalMatrix
};
instanceMatrix.SetData(matrices, 0);
MeshData initialData = new MeshData();
initialData.subMeshes = new SubMeshData[1];
initialData.subMeshes[0] = new SubMeshData(vertices, indices);
defaultMesh = new Mesh(GraphicsContext.graphicsDevice, initialData, true);
}
public override (SurfaceInteraction, double) Sample()
{
// TODO: Implement Sphere sampling
if (Outside)
{
var pObj = this.Radius * Samplers.UniformSampleSphere();
var n = new Vector3(pObj.x, pObj.y, pObj.z);
var pdf = 1 / this.Area();
var dpdu = new Vector3(-pObj.y, pObj.x, 0);
SurfaceInteraction si = new SurfaceInteraction(pObj, n, Vector3.ZeroVector, dpdu, this);
return(ObjectToWorld.Apply(si), pdf);
}
else
{
var pObj = this.Radius * Samplers.UniformSampleSphere();
var n = new Vector3(pObj.x, pObj.y, pObj.z);
var pdf = 1 / this.Area();
var dpdu = new Vector3(-pObj.y, pObj.x, 0);
SurfaceInteraction si = new SurfaceInteraction(pObj, -n, Vector3.ZeroVector, dpdu, this);
return(ObjectToWorld.Apply(si), pdf);
}
// TODO: Return surface interaction and pdf
// A dummy return example
//double dummyPdf = 1.0;
//Vector3 dummyVector = new Vector3(0, 0, 0);
//SurfaceInteraction dummySurfaceInteraction = new SurfaceInteraction(dummyVector, dummyVector, dummyVector, dummyVector, this);
//return (dummySurfaceInteraction, dummyPdf);
}
public override Point Sample(float u1, float u2, out Normal ns)
{
var z = MathUtility.Lerp(u1, _zMin, _zMax);
var t = u2 * _phiMax;
var p = new Point(_radius * MathUtility.Cos(t), _radius * MathUtility.Sin(t), z);
ns = Normal.Normalize(ObjectToWorld.TransformNormal(new Normal(p.X, p.Y, 0)));
if (ReverseOrientation)
ns *= -1.0f;
return ObjectToWorld.TransformPoint(ref p);
}
public override Point Sample(float u1, float u2, out Normal ns)
{
Point p = new Point(0, 0, 0) + _radius * MonteCarloUtilities.UniformSampleSphere(u1, u2);
ns = Normal.Normalize(ObjectToWorld.TransformNormal(new Normal(p.X, p.Y, p.Z)));
if (ReverseOrientation)
{
ns *= -1.0f;
}
return(ObjectToWorld.TransformPoint(ref p));
}
public override (SurfaceInteraction, double) Sample()
{
var pObj = Samplers.UniformSampleSphere() * Radius;
pObj *= Radius / pObj.Length(); // refine
var n = pObj.Normalize();
var dpdu = new Vector3(-pObj.y, pObj.x, 0);
var pdf = 1 / Area();
return(ObjectToWorld.Apply(new SurfaceInteraction(pObj, n, Vector3.ZeroVector, dpdu, this)), pdf);
}
public override (SurfaceInteraction, double) Sample()
{
(double x, double y) = Samplers.UniformSampleDisk();
var pObj = new Vector3(x * radius, y * radius, height);
var n = new Vector3(0, 0, 1);
var dpdu = new Vector3(-pObj.y, pObj.x, 0);
double pdf = 1 / Area();
return(ObjectToWorld.Apply(new SurfaceInteraction(pObj, n, Vector3.ZeroVector, dpdu, this)), pdf);
}
public override (SurfaceInteraction, double) Sample()
{
(double x, double y) = Samplers.UniformSampleSquare();
var pObj = new Vector3((x - 0.5) * width, (y - 0.5) * height, 0);
var n = new Vector3(0, 0, 1);
var dpdu = new Vector3(1, 0, 0);
double pdf = 1 / Area();
return(ObjectToWorld.Apply(new SurfaceInteraction(pObj, n, Vector3.ZeroVector, dpdu, this)), pdf);
}
public override (SurfaceInteraction, double) Sample()
{
Vector3 sample = Samplers.UniformSampleSphere();
Vector3 point = sample * Radius;
Vector3 normal = sample;
Vector3 dpdu = new Vector3(-normal.y, normal.x, 0.0);
double pdf = 1.0 / Area();
SurfaceInteraction si = new SurfaceInteraction(point, normal, Vector3.ZeroVector, dpdu, this);
return(ObjectToWorld.Apply(si), pdf);
}
public override (SurfaceInteraction, double) Sample()
{
// TODO: Implement Sphere sampling
//Vector3 pObj = Samplers.CosineSampleHemisphere() * Radius;
Vector3 pObj = Samplers.UniformSampleSphere() * Radius;
pObj = pObj * (Radius / pObj.Length());
// TODO: Return surface interaction and pdf
var dpdu = new Vector3(-pObj.y, pObj.x, 0);
double pdf = 1 / Area(); // a je kle inv 4 PI (1/Math.PI/4)
return(ObjectToWorld.Apply(new SurfaceInteraction(pObj, ObjectToWorld.ApplyNormal(pObj), Vector3.ZeroVector, dpdu, this)), pdf);
}
public override SampledSpectrum Sample(ref Vector3 point, Scene scene, out Vector3 incomingVector,
out VisibilityTester visibilityTester)
{
var r1 = StaticRandom.NextFloat() * 2 - 1;
var r2 = StaticRandom.NextFloat() * 2 - 1;
var pointInDiskLocal = new Vector3(r1 * _radius, 0, r2 * _radius);
var pointInDiskWorld = ObjectToWorld.TransformPoint(ref pointInDiskLocal);
incomingVector = point - pointInDiskWorld;
var cosangle = Vector3.Dot(incomingVector.Normalized(), _normal);
visibilityTester = new VisibilityTester(pointInDiskWorld, point, scene);
return(Spectrum * cosangle / incomingVector.Length);
}
public override Point Sample(float u1, float u2, out Normal ns)
{
var p = new Point();
MonteCarloUtilities.ConcentricSampleDisk(u1, u2, out p.X, out p.Y);
p.X *= _radius;
p.Y *= _radius;
p.Z = _height;
ns = Normal.Normalize(ObjectToWorld.TransformNormal(new Normal(0, 0, 1)));
if (ReverseOrientation)
{
ns *= -1.0f;
}
return(ObjectToWorld.TransformPoint(ref p));
}
public override float Pdf(Point p, Vector wi)
{
Point Pcenter = ObjectToWorld.TransformPoint(Point.Zero);
// Return uniform weight if point inside sphere
if (Point.DistanceSquared(p, Pcenter) - _radius * _radius < 1e-4f)
{
return(base.Pdf(p, wi));
}
// Compute general sphere weight
float sinThetaMax2 = _radius * _radius / Point.DistanceSquared(p, Pcenter);
float cosThetaMax = MathUtility.Sqrt(Math.Max(0.0f, 1.0f - sinThetaMax2));
return(MonteCarloUtilities.UniformConePdf(cosThetaMax));
}
public override (SurfaceInteraction, double) Sample(SurfaceInteraction _si)
{
SurfaceInteraction si = WorldToObject.Apply(_si);
double dc2 = si.Point.LengthSquared();
if (dc2 <= Radius * Radius)
{
// Point inside sphere
return(base.Sample(_si));
}
// Point outside sphere
double dc = Math.Sqrt(dc2);
double sinThetaMax = Radius / dc;
double cosThetaMax = Utils.SinToCos(sinThetaMax);
// Determine theta and phi for uniform cone sampling
double cosTheta = (cosThetaMax - 1) * Samplers.ThreadSafeRandom.NextDouble() + 1;
double sinTheta = Utils.CosToSin(cosTheta);
double phi = Samplers.ThreadSafeRandom.NextDouble() * 2.0 * Math.PI;
// Distance between reference point and sample point on sphere
double ds = dc * cosTheta - Math.Sqrt(Math.Max(0, Radius * Radius - dc2 * sinTheta * sinTheta));
// Kosinusni zakon
double cosAlpha = (dc2 + Radius * Radius - ds * ds) / (2 * dc * Radius);
double sinAlpha = Utils.CosToSin(cosAlpha);
// Construct coordinate system and use phi and theta as spherical coordinates to get point on sphere
Vector3 wcZ = si.Point.Clone().Normalize();
(Vector3 wcX, Vector3 wcY) = Utils.CoordinateSystem(wcZ);
Vector3 nObj = Utils.SphericalDirection(sinAlpha, cosAlpha, phi, wcX, wcY, wcZ);
Vector3 pObj = nObj * Radius;
// Surface interaction
Vector3 dpdu = new Vector3(-nObj.y, nObj.x, 0.0);
SurfaceInteraction siSample = new SurfaceInteraction(pObj, nObj, Vector3.ZeroVector, dpdu, this);
// Uniform cone PDF
double pdf = Samplers.UniformConePdf(cosThetaMax);
return(ObjectToWorld.Apply(siSample), pdf);
}
public override (SurfaceInteraction, double) Sample()
{
// TODO: Implement Sphere sampling
var center = new Vector3(0, 0, 0);
var point = center + Radius * Samplers.UniformSampleSphere();
var normal = point.Normalize();
if (innerOrientation)
{
normal = -normal;
}
point *= Radius / (center - point).Length();
var wo = point;
var dpdu = Dpdu(point);
var interaction = new SurfaceInteraction(point, normal, wo, dpdu, this);
return(ObjectToWorld.Apply(interaction), Pdf(interaction, point));
}
public override Point Sample(Point p, float u1, float u2, out Normal ns)
{
// Compute coordinate system for sphere sampling
Point Pcenter = ObjectToWorld.TransformPoint(Point.Zero);
Vector wc = Vector.Normalize(Pcenter - p);
Vector wcX, wcY;
Vector.CoordinateSystem(wc, out wcX, out wcY);
// Sample uniformly on sphere if $\pt{}$ is inside it
if (Point.DistanceSquared(p, Pcenter) - _radius * _radius < 1e-4f)
{
return(Sample(u1, u2, out ns));
}
// Sample sphere uniformly inside subtended cone
float sinThetaMax2 = _radius * _radius / Point.DistanceSquared(p, Pcenter);
float cosThetaMax = MathUtility.Sqrt(Math.Max(0.0f, 1.0f - sinThetaMax2));
DifferentialGeometry dgSphere;
float thit, rayEpsilon;
Point ps;
Ray r = new Ray(p, MonteCarloUtilities.UniformSampleCone(u1, u2, cosThetaMax, ref wcX, ref wcY, ref wc),
1e-3f);
if (!TryIntersect(r, out thit, out rayEpsilon, out dgSphere))
{
thit = Vector.Dot(Pcenter - p, Vector.Normalize(r.Direction));
}
ps = r.Evaluate(thit);
ns = (Normal)Vector.Normalize(ps - Pcenter);
if (ReverseOrientation)
{
ns *= -1.0f;
}
return(ps);
}
public override (double?, SurfaceInteraction) Intersect(Ray ray)
{
Ray r = WorldToObject.Apply(ray);
// TODO: Compute quadratic sphere coefficients
// TODO: Initialize _double_ ray coordinate values
(double dx, double dy, double dz) = (r.d.x, r.d.y, r.d.z);
(double ox, double oy, double oz) = (r.o.x, r.o.y, r.o.z);
double a = dx * dx + dy * dy + dz * dz;
double b = 2 * (dx * ox + dy * oy + dz * oz);
double c = ox * ox + oy * oy + oz * oz - this.Radius * this.Radius;
// TODO: Solve quadratic equation for _t_ values
(bool zzz, double t0, double t1) = Utils.Quadratic(a, b, c);
if (!zzz)
{
return(null, null);
}
// TODO: Check quadric shape _t0_ and _t1_ for nearest intersection
//double tShapeHit;
//if (t1 < Renderer.Epsilon)
// return (null, null);
//if (t0 < Renderer.Epsilon)
// tShapeHit = t1;
//else
//{
// Ray temp = new Ray(r.o, r.d);
// double d1 = Vector3.Dot(temp.Point(t0), temp.o);
// double d2 = Vector3.Dot(temp.Point(t1), temp.o);
// if (d1 == d2)
// return (null, null);
// else if (d1 > d2)
// {
// if (Outside)
// tShapeHit = t0;
// else
// tShapeHit = t1;
// }
// else
// {
// if (Outside)
// tShapeHit = t1;
// else
// tShapeHit = t0;
// }
//}
//if (t1 - t0 <= Renderer.Epsilon)
// return (null, null);
//Ray temp = new Ray(r.o, r.d);
//double d0 = Vector3.Dot(temp.o, temp.Point(t0));
//double d1 = Vector3.Dot(temp.o, temp.Point(t1));
//double tShapeHit;
//if (d0 >= d1)
// tShapeHit = t0;
//else
// tShapeHit = t1;
if (Outside)
{
Console.WriteLine("HERE");
//if (t1 < Renderer.Epsilon)
// return (null, null);
//double tShapeHit = t0;
//if (tShapeHit < Renderer.Epsilon)
//{
// tShapeHit = t1;
//}
double tShapeHit;
Ray temp = new Ray(r.o, r.d);
Vector3 p_t0 = temp.Point(t0);
Vector3 p_t1 = temp.Point(t1);
double d0 = Math.Sqrt(Math.Pow(temp.o.x - p_t0.x, 2) + Math.Pow(temp.o.y - p_t0.y, 2) + Math.Pow(temp.o.z - p_t0.z, 2));
double d1 = Math.Sqrt(Math.Pow(temp.o.x - p_t1.x, 2) + Math.Pow(temp.o.y - p_t1.y, 2) + Math.Pow(temp.o.z - p_t1.z, 2));
if (d0 > d1)
{
tShapeHit = t1;
}
else
{
tShapeHit = t0;
}
//// TODO: Compute sphere hit position and $\phi$
Vector3 pHit = r.Point(tShapeHit);
//pHit *= Radius / Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z);
//if (Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z) >= this.Radius + Renderer.Epsilon)
// return (null, null);
//if (Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z) <= this.Radius - Renderer.Epsilon)
// return (null, null);
//double phi = Math.Atan2(pHit.y, pHit.x);
//if (phi < 0)
// phi += 2 * Math.PI;
//double theta = Math.Acos(Utils.Clamp(pHit.z / this.Radius, -1, 1));
//double invR = 1 / Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y);
//Vector3 n = new Vector3(pHit.z * pHit.x * invR, pHit.z * pHit.y * invR, -this.Radius * Math.Sin(theta));
Vector3 n = (ObjectToWorld.ApplyPoint(pHit) - ObjectToWorld.ApplyPoint(Vector3.ZeroVector)).Clone().Normalize();
//Vector3 n = new Vector3(0, 0, 1);
//Vector3 n = pHit.Clone() * this.Radius;
// TODO: Return shape hit and surface interaction
Vector3 dpdu = new Vector3(-pHit.y, pHit.x, 0);
//Console.WriteLine("dpdu1 " + dpdu.x + " " + dpdu.y + " " + dpdu.z);
n.Faceforward(dpdu);
//Console.WriteLine("normal " + n.x + " " + n.y + " " + n.z);
double abDot = Vector3.Dot(n, dpdu);
double bbDot = Vector3.Dot(n, n);
Vector3 proj = abDot / bbDot * n;
dpdu -= proj;
//Console.WriteLine("proj " + proj.x + " " + proj.y + " " + proj.z);
//Console.WriteLine("dot " + Vector3.Dot(n, dpdu));
var si = new SurfaceInteraction(pHit, n, -ray.d, dpdu, this);
//var si = new SurfaceInteraction(pHit, new Vector3(0, 0, 1), -ray.d, dpdu, this);
return(tShapeHit, ObjectToWorld.Apply(si));
}
else
{
//Console.WriteLine(r.o.x + " " + r.o.y + " " + r.o.z);
//Console.WriteLine(t0);
//Console.WriteLine(t1);
//System.Environment.Exit(1);
double tShapeHit;
Ray temp = new Ray(r.o, r.d);
Vector3 p_t0 = temp.Point(t0);
Vector3 p_t1 = temp.Point(t1);
Vector3 x = p_t0 - temp.o;
Vector3 y = p_t1 - temp.o;
double x_x = Vector3.Dot(x, temp.d);
double y_x = Vector3.Dot(y, temp.d);
//Console.WriteLine(temp.d.x + " " + temp.d.y + " " + temp.d.z);
//Console.WriteLine(x_x);
//Console.WriteLine(y_x);
//System.Environment.Exit(1);
if (x_x > 0)
{
tShapeHit = t0;
}
else if (y_x > 0)
{
tShapeHit = t1;
}
else
{
return(null, null);
}
//// TODO: Compute sphere hit position and $\phi$
Vector3 pHit = r.Point(tShapeHit);
//pHit *= Radius / Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z);
//if (Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z) >= this.Radius + Renderer.Epsilon)
// return (null, null);
//if (Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y + pHit.z * pHit.z) <= this.Radius - Renderer.Epsilon)
// return (null, null);
//double phi = Math.Atan2(pHit.y, pHit.x);
//if (phi < 0)
// phi += 2 * Math.PI;
//double theta = Math.Acos(Utils.Clamp(pHit.z / this.Radius, -1, 1));
//double invR = 1 / Math.Sqrt(pHit.x * pHit.x + pHit.y * pHit.y);
//Vector3 n = new Vector3(pHit.z * pHit.x * invR, pHit.z * pHit.y * invR, -this.Radius * Math.Sin(theta));
Vector3 n = (ObjectToWorld.ApplyPoint(Vector3.ZeroVector) - ObjectToWorld.ApplyPoint(pHit)).Clone().Normalize();
//Vector3 n = new Vector3(0, 0, 1);
//Vector3 n = pHit.Clone() * this.Radius;
// TODO: Return shape hit and surface interaction
Vector3 dpdu = new Vector3(-pHit.y, pHit.x, 0);
//Console.WriteLine("dpdu1 " + dpdu.x + " " + dpdu.y + " " + dpdu.z);
dpdu.Faceforward(n);
//Console.WriteLine("normal " + n.x + " " + n.y + " " + n.z);
double abDot = Vector3.Dot(n, dpdu);
double bbDot = Vector3.Dot(n, n);
Vector3 proj = abDot / bbDot * n;
dpdu -= proj;
//Console.WriteLine("proj " + proj.x + " " + proj.y + " " + proj.z);
//Console.WriteLine("dot " + Vector3.Dot(n, dpdu));
var si = new SurfaceInteraction(pHit, n, -ray.d, dpdu, this);
//var si = new SurfaceInteraction(pHit, new Vector3(0, 0, 1), -ray.d, dpdu, this);
return(tShapeHit, ObjectToWorld.Apply(si));
}
// A dummy return example
//double dummyHit = 0.0;
//Vector3 dummyVector = new Vector3(0, 0, 0);
//SurfaceInteraction dummySurfaceInteraction = new SurfaceInteraction(dummyVector, dummyVector, dummyVector, dummyVector, this);
//return (dummyHit, dummySurfaceInteraction);
}
public virtual Bounds3D WorldBound()
{
return(ObjectToWorld.AtBounds(ObjectBound()));
}
