// sample: samples a single path up to a maximum depth
private Vector3 Sample(Ray ray, int depth, int x, int y)
{
// find nearest ray/scene intersection
Scene.Intersect(ray);
if (ray.objIdx == -1)
{
// no scene primitive encountered; skybox
return(1.0f * scene.SampleSkydome(ray.D));
}
// calculate intersection point
Vector3 I = ray.O + ray.t * ray.D;
// get material at intersection point
Material material = scene.GetMaterial(ray.objIdx, I);
if (material.emissive)
{
// hit light
return(material.diffuse);
}
// terminate if path is too long
if (depth >= MAXDEPTH)
{
return(Vector3.Zero);
}
// handle material interaction
float r0 = RTTools.RandomFloat();
Vector3 R = Vector3.Zero;
if (r0 < material.refr)
{
// dielectric: refract or reflect
RTTools.Refraction(ray.inside, ray.D, ray.N, ref R);
Ray extensionRay = new Ray(I + R * EPSILON, R, 1e34f);
extensionRay.inside = (Vector3.Dot(ray.N, R) < 0);
return(material.diffuse * Sample(extensionRay, depth + 1, x, y));
}
else if ((r0 < (material.refl + material.refr)) && (depth < MAXDEPTH))
{
// pure specular reflection
R = Vector3.Reflect(ray.D, ray.N);
Ray extensionRay = new Ray(I + R * EPSILON, R, 1e34f);
return(material.diffuse * Sample(extensionRay, depth + 1, x, y));
}
else
{
// diffuse reflection
if (x == 500 && y == 400)
{
//Console.WriteLine("test");
//return new Vector3(255,255,255);
}
R = RTTools.DiffuseReflection(RTTools.GetRNG(), ray.N);
Ray extensionRay = new Ray(I + R * EPSILON, R, 1e34f);
return(Vector3.Dot(R, ray.N) * material.diffuse * Sample(extensionRay, depth + 1, x, y));
}
}
public void Update()
{
// construct a look-at matrix
E = Vector3.Normalize(target - pos);
up = Vector3.UnitY;
right = Vector3.Cross(up, E);
float[] rightxs = { right.X, right.X, right.X, right.X };
float[] rightys = { right.Y, right.Y, right.Y, right.Y };
float[] rightzs = { right.Z, right.Z, right.Z, right.Z };
rightx4 = new Vector <float>(rightxs);
righty4 = new Vector <float>(rightys);
rightz4 = new Vector <float>(rightzs);
up = Vector3.Cross(E, right);
float[] upxs = { up.X, up.X, up.X, up.X };
float[] upys = { up.Y, up.Y, up.Y, up.Y };
float[] upzs = { up.Z, up.Z, up.Z, up.Z };
upx4 = new Vector <float>(upxs);
upy4 = new Vector <float>(upys);
upz4 = new Vector <float>(upzs);
// calculate focal distance
Ray ray = new Ray(pos, E, 1e34f);
Scene.Intersect(ray);
focalDistance = Math.Min(20, ray.t);
// calculate virtual screen corners
Vector3 C = pos + focalDistance * E;
p1 = C - 0.5f * focalDistance * aspectRatio * right + 0.5f * focalDistance * up;
p2 = C + 0.5f * focalDistance * aspectRatio * right + 0.5f * focalDistance * up;
p3 = C - 0.5f * focalDistance * aspectRatio * right - 0.5f * focalDistance * up;
float[] p1sX = { p1.X, p1.X, p1.X, p1.X };
float[] p2sX = { p2.X, p2.X, p2.X, p2.X };
float[] p3sX = { p3.X, p3.X, p3.X, p3.X };
float[] p1sY = { p1.Y, p1.Y, p1.Y, p1.Y };
float[] p2sY = { p2.Y, p2.Y, p2.Y, p2.Y };
float[] p3sY = { p3.Y, p3.Y, p3.Y, p3.Y };
float[] p1sZ = { p1.Z, p1.Z, p1.Z, p1.Z };
float[] p2sZ = { p2.Z, p2.Z, p2.Z, p2.Z };
float[] p3sZ = { p3.Z, p3.Z, p3.Z, p3.Z };
p1x4 = new Vector <float>(p1sX);
p1y4 = new Vector <float>(p1sY);
p1z4 = new Vector <float>(p1sZ);
p2x4 = new Vector <float>(p2sX);
p2y4 = new Vector <float>(p2sY);
p2z4 = new Vector <float>(p2sZ);
p3x4 = new Vector <float>(p3sX);
p3y4 = new Vector <float>(p3sY);
p3z4 = new Vector <float>(p3sZ);
}
public void Update()
{
// construct a look-at matrix
E = Vector3.Normalize(target - pos);
up = Vector3.UnitY;
right = Vector3.Cross(up, E);
up = Vector3.Cross(E, right);
// calculate focal distance
Ray ray = new Ray(pos, E, 1e34f);
Scene.Intersect(ray);
focalDistance = Math.Min(20, ray.t);
// calculate virtual screen corners
Vector3 C = pos + focalDistance * E;
p1 = C - 0.5f * focalDistance * aspectRatio * right + 0.5f * focalDistance * up;
p2 = C + 0.5f * focalDistance * aspectRatio * right + 0.5f * focalDistance * up;
p3 = C - 0.5f * focalDistance * aspectRatio * right - 0.5f * focalDistance * up;
}
