public void Execute(Random rand, PixelBuffer pb)
{
var w = Scene.ImageWidth;
var h = Scene.ImageHeight;
var samps = Scene.SamplesPerPixel;
var cam = Scene.Camera;
var cx = new Vec(w * 0.5135 / h);
var cy = cx.Cross(cam.Direction).Norm * 0.5135;
for (var py = 0; py < Height; py++)
{
for (var px = 0; px < Width; px++)
{
var x = X + px;
var y = Y + py;
var c = new Vec();
for (var sy = 0; sy < 2; sy++)
{
for (var sx = 0; sx < 2; sx++)
{
var r = new Vec();
for (var s = 0; s < samps; s++)
{
Prec r1 = 2 * rand.NextDouble(), dx = r1 < 1 ? Math.Sqrt(r1) - 1 : 1 - Math.Sqrt(2 - r1);
Prec r2 = 2 * rand.NextDouble(), dy = r2 < 1 ? Math.Sqrt(r2) - 1 : 1 - Math.Sqrt(2 - r2);
Vec d = cx * (((sx + .5 + dx) / 2 + x) / w - .5) +
cy * (((sy + .5 + dy) / 2 + y) / h - .5) + cam.Direction;
r += Radiance(new Ray(cam.Origin + d * 140, d.Norm), 0, rand) * (1.0 / samps);
}
c += r * 0.25;
}
}
pb.PutPixel(px, py, c);
}
}
}
