public BVHNode(Hitable[] list, int low, int high, float t0, float t1)
{
if (low < 0 || high > list.Length)
{
throw new Exception("BVHNode Contruction error low <0 || high >list.Length");
}
int length = high - low;
if (length <= 0)
{
throw new Exception("BVHNode Contruction error low >= high");
}
if (length == 1)
{
_left = _right = list[low];
_box = _left.BoundVolume(t0, t1);
}
else if (length == 2)
{
_left = list[low];
_right = list[low + 1];
_box = AABB.SurroundingBox(_left.BoundVolume(t0, t1), _right.BoundVolume(t0, t1));
}
else
{
Array.Sort(list, low, high - low, new BVHComparer((int)(3 * Exten.rand01())));
int mid = (low + high) / 2;
_left = new BVHNode(list, low, mid, t0, t1);
_right = new BVHNode(list, mid, high, t0, t1);
_box = AABB.SurroundingBox(_left.BoundVolume(t0, t1), _right.BoundVolume(t0, t1));
}
}
public Ray GenRay(float s, float t)
{
vec3 offset = lenRadius * random_in_unit_disk();
var point = origin + offset;
var time = openTime + (closeTime - openTime) * Exten.rand01();
return(new Ray(point, lower_left_corner + s * horizontal + t * vertical - point, time));
}
vec3 random_in_unit_disk()
{
vec3 p;
do
{
p = 2.0f * new vec3(Exten.rand01(), Exten.rand01(), 0) - new vec3(1, 1, 0);
} while (glm.dot(p, p) >= 1.0f);
return(p);
}
void shuff(int [] vs)
{
for (int i = 0; i < vs.Length - 1; ++i)
{
int nextIdx = i + 1 + (int)((vs.Length - i - 1) * Exten.rand01());
var temp = vs[i];
vs[i] = vs[nextIdx];
vs[nextIdx] = temp;
}
}
public vec3 RandomCosineDir()
{
float r1 = Exten.rand01();
float r2 = Exten.rand01() / fuzz;
r2 = (float)Math.Pow(2.72, -r2*r2);
double z = Math.Sqrt(1 - r2);
double phi = 2 * Math.PI * r1;
double x = Math.Cos(phi) * Math.Sqrt(r2);
double y = Math.Sin(phi) * Math.Sqrt(r2);
return new vec3((float)x, (float)y, (float)z);
}
public vec3 Generate(vec3 point, vec3 normal)
{
float r1 = Exten.rand01();
float r2 = Exten.rand01();
var pc = _sphere.GetCenter(0) - point;
float cosMax = MathF.Sqrt(1 - _sphere.radius * _sphere.radius / glm.dot(pc, pc));
float z = 1 + r2 * (cosMax - 1);
float phi = r1 * 2.0f * MathF.PI;
float x = MathF.Cos(phi) * MathF.Sqrt(1 - z * z);
float y = MathF.Sin(phi) * MathF.Sqrt(1 - z * z);
ONB oNB = new ONB(glm.normalize(pc));
return(oNB.Local(x, y, z));
}
public Noise()
{
for (int i = 0; i < _randomValue.Length; ++i)
{
_randomValue[i] = Exten.rand01();
}
for (int i = 0; i < maxL; ++i)
{
_xAxis[i] = i; //(int)(maxL * Exten.rand01());
_yAxis[i] = i; //(int)(maxL * Exten.rand01());
_zAxis[i] = i; //(int)(maxL * Exten.rand01());
}
shuff(_xAxis);
shuff(_yAxis);
shuff(_zAxis);
}
public vec3 Generate(vec3 point, vec3 normal)
{
var r = Exten.rand01();
if (r < 0.5f)
{
return(_pdfs[0].Generate(point, normal));
}
else if (r < 0.75f)
{
return(_pdfs[1].Generate(point, normal));
}
else
{
return(_pdfs[2].Generate(point, normal));
}
}
static Hitable FinalTest()
{
int nb = 20;
Hitable[] list = new Hitable[30];
Hitable[] boxlist = new Hitable[10000];
Material ground = new Lambertian(new SolidTexture(new vec3(0.48f, 0.83f, 0.53f)));
int b = 0;
for (int i = 0; i < nb; i++)
{
for (int j = 0; j < nb; j++)
{
float w = 100;
float x0 = -1000 + i * w;
float z0 = -1000 + j * w;
float y0 = 0;
float x1 = x0 + w;
float y1 = 100 * (Exten.rand01() + 0.01f);
float z1 = z0 + w;
boxlist[b++] = new Box(new vec3(x0, y0, z0), new vec3(x1, y1, z1), ground);
}
}
int l = 0;
list[l++] = new BVHNode(boxlist, 0, b, 0, 1);
Material light = new DiffuseLight(new SolidTexture(new vec3(7, 7, 7)));
list[l++] = new XZRect(554, 123, 423, 147, 412, light);
vec3 center = new vec3(400, 400, 200);
//public Sphere(vec3 c, vec3 c1, float r, Material m, float time1, float time2)
list[l++] = new Sphere(center, center + new vec3(30, 0, 0), 50, new Lambertian(new SolidTexture(new vec3(0.7f, 0.3f, 0.1f))), 0, 1);
list[l++] = new Sphere(new vec3(260, 150, 45), 50, new Dieletric(1.5f));
list[l++] = new Sphere(new vec3(0, 150, 145), 50, new Metal(new vec3(0.8f, 0.8f, 0.9f), 10.0f));
Hitable boundary = new Sphere(new vec3(360, 150, 145), 70, new Dieletric(1.5f));
list[l++] = boundary;
boundary = new Sphere(new vec3(0, 0, 0), 5000, new Dieletric(1.5f));
Texture pertext = new NoiseTexture(new Noise());
list[l++] = new Sphere(new vec3(220, 280, 300), 80, new Lambertian(pertext));
return(new HitList(list.Where(arg => arg != null).ToArray()));
}
public bool Scatter(Ray ray, HitRecord hitRecord, out ScatterRecord sRecord)
{
sRecord = new ScatterRecord();
var normal = hitRecord.normal;
var point = hitRecord.point;
sRecord.attenuation = new vec3(1.0f, 1.0f, 1.0f);
float eta = ref_idx;
var n = normal;
if (glm.dot(ray.direction, normal) > 0)//从内到外
{
n = new vec3(-normal.x, -normal.y, -normal.z);
}
else
{
eta = 1.0f / eta;
}
vec3 r;
float prob = 1.0f;
if (Exten.refract(ray.direction, n, eta, out r))
{
float cosi = -glm.dot(ray.direction, n);
float cost = -glm.dot(r, n);
prob = fresnel(cosi, cost, eta);
}
if (Exten.rand01() < prob)
{
vec3 reflected = Exten.reflect(ray.direction, normal);
sRecord.pdf = new ConstPDF(reflected);
}
else
{
sRecord.pdf = new ConstPDF(r);
}
return true;
}
static float drand48()
{
return(Exten.rand01());
}
public static void Main(string[] args)
{
Exten.r = new Random(0);
int width = 600;
int height = 300;
string outPath = "1.png";
int sampleCount = 5;
bool bvh = false;
if (args.Length >= 1)
{
sampleCount = int.Parse(args[0]);
}
if (args.Length >= 2)
{
width = int.Parse(args[1]);
}
if (args.Length >= 3)
{
height = int.Parse(args[2]);
}
if (args.Length >= 4)
{
outPath = args[3];
}
if (args.Length >= 5)
{
bvh = bool.Parse(args[4]);
}
scene = CornellBox(); // SimpleLight(); //random_scene(bvh);
vec3 lookfrom = new vec3(278, 278, -800);
vec3 lookat = new vec3(278, 278, 0);
float dist_to_focus = 10.0f;
float aperture = 0.0f;
Camera camera = new Camera(lookfrom, lookat, new vec3(0, 1, 0), 40, (float)(width) / (float)(height), aperture, dist_to_focus, 0, 1);
Bitmap bmp = new Bitmap(width, height);
for (int i = height - 1; i >= 0; --i)
{
ShowProgress((height - i) / (float)height);
for (int j = 0; j < width; ++j)
{
var c = new vec3(0, 0, 0);
for (int k = 0; k < sampleCount; ++k)
{
float x = (j + Exten.rand01()) / (float)width;
float y = (i + Exten.rand01()) / (float)height;
var ray = camera.GenRay(x, y);
c += RayTracing(ray, 0);
}
c /= sampleCount;
//printColor(c.gamma());
c = c.gamma();
int r = (int)(c.x * 255.99f);
int g = (int)(c.y * 255.99f);
int b = (int)(c.z * 255.99f);
r = clamp(r, 0, 255);
g = clamp(g, 0, 255);
b = clamp(b, 0, 255);
Color o = Color.FromArgb(r, g, b);
#if UNITY_EDITOR
bmp.SetPixel(j, i, o);
#else
bmp.SetPixel(j, height - i - 1, o);
#endif
}
}
bmp.Save(outPath, ImageFormat.Png);
HideProgress();
}