public Color CalcPixelColor(ref long seed, ref int maxDepth, int x, int y, PixelDebugData debug)
{
if (debug != null)
{
debug.Points.Add(Origin);
}
Color accumulateColor = Color.black;
int c = debug == null ? AntiAliasRayCount : 1;
for (int i = 0; i < c; ++i)
{
var offsetx = (debug == null ? SimpleRandom.RandNorm(ref seed) : 0.5f) * StepX;
var offsety = (debug == null ? SimpleRandom.RandNorm(ref seed) : 0.5f) * StepY;
var dir = new Vector4(StartX + x * StepX + offsetx, StartY + y * StepY + offsety, 1, 0);
var dir2 = CameraLocal2World * dir;
Ray ray = new Ray(Origin, dir2.normalized);
accumulateColor += TraceScene(ref seed, ref maxDepth, ray, 0, debug);
}
Color col = accumulateColor / c;
if (GammarCorrection)
{
col.r = Mathf.Sqrt(col.r);
col.g = Mathf.Sqrt(col.g);
col.b = Mathf.Sqrt(col.b);
}
col.a = 1;
return(col);
}
public bool Scatter(PixelDebugData debug, ref long seed, Ray rayIn, ref HitRecord hit, out Color atten, out Ray scattered)
{
switch (MatType)
{
case RayTracingMaterialType.Lambert:
{
Vector3 dir = hit.Normal * 1.0001f;
if (debug == null)
{
dir += SimpleRandom.RandomInsideUnitSphere(ref seed);
}
Ray rayOut = new Ray();
rayOut.origin = hit.Point;
rayOut.direction = Vector3.Normalize(dir);
scattered = rayOut;
atten = Albedo;
return(true);
}
case RayTracingMaterialType.Metal:
{
Vector3 dir = Reflect(rayIn.direction, hit.Normal);
Ray rayOut = new Ray();
rayOut.origin = hit.Point;
rayOut.direction = Vector3.Normalize(dir);
scattered = rayOut;
atten = Albedo;
return(Vector3.Dot(rayOut.direction, hit.Normal) > 0);
}
case RayTracingMaterialType.Dielectric:
{
Vector3 N = hit.Normal;
Vector3 R = Reflect(rayIn.direction, N);
atten = Color.white;
float ni_over_nt = Mathf.Max(0.1f, RefractionIndex);
if (Vector3.Dot(rayIn.direction, N) > 0)
{
// Ray travel through inside
N = -N;
}
else
{
// Ray comming from outside
ni_over_nt = 1.0f / ni_over_nt;
}
Vector3 refracted;
float reflect_prob = 1.0f;
if (Refract(rayIn.direction, N, ni_over_nt, out refracted))
{
reflect_prob = Schlick(Vector3.Dot(N, -rayIn.direction), RefractionIndex);
}
if (SimpleRandom.RandNorm(ref seed) < reflect_prob)
{
scattered = new Ray(hit.Point, R);
}
else
{
scattered = new Ray(hit.Point, refracted);
}
return(true);
}
}
atten = Color.black;
scattered = new Ray();
return(false);
}