/// <summary>
/// 利用层次包围盒计算颜色
/// </summary>
/// <param name="r"></param>
/// <param name="world"></param>
/// <param name="depth"></param>
/// <returns></returns>
public static SColor Color(Ray r, BVH_node world, int depth)
{
AABB aBB = new AABB();
world.Bounding_box(0, 0, ref aBB);
if (aBB.Hit(r, 1e-5))
{
ShadeRec rec = new ShadeRec();
world.Hit(r, 1e-5, ref rec);
if (rec.IsHit)
{
Ray scattered = new Ray();
Vector3D attenuation = new Vector3D();
SColor emitted = rec.Material.Emitted(rec);//光颜色
if (depth < 1 && rec.Material.Scatter(r, rec, ref attenuation, ref scattered))
{
SColor colorTemp = Color(scattered, world, depth + 1);
colorTemp = colorTemp * new SColor(attenuation);
//有反射则将当前发光体发出的光和散射的颜色预以叠加
return(colorTemp + emitted);
}
else
{
//无反射则直接取发光射出的颜色
return(emitted);
}
}
else
{
Vector3D unitDirection = Vector3D.UnitVector(r.Direction);
double t = 0.5 * (unitDirection.Y + 1.0);
return(new SColor((1.0 - t) + t * 0.5, (1.0 - t) + t * 0.7, (1.0 - t) + t * 1));
// return new SColor(1, 1, 1);//无背景色
}
}
else
{
Vector3D unitDirection = Vector3D.UnitVector(r.Direction);
double t = 0.5 * (unitDirection.Y + 1.0);
return(new SColor((1.0 - t) + t * 0.5, (1.0 - t) + t * 0.7, (1.0 - t) + t * 1));
// return new SColor(1, 0, 0);//无背景色
}
}
/// <summary>
/// 渲染
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Btn_render_Click(object sender, EventArgs e)
{
//开始时间
DateTime startTime = DateTime.Now;
//构建世界
World world = new World();
world.Bulid();//根据bulid构建
//world = World.RandomScene1();//随机构建函数1（封面图1）
//world = World.RandomScene2();//随即构建函数2（封面图2）
//根据world的物体构造层次包围盒树
BVH_node bVH = new BVH_node(world.GeometryObjects, world.GeometryObjects.Count, 0, 0);
//画布参数
int nx = 200; //宽
int ny = 100; //高
Bitmap bitmap = new Bitmap(nx, ny); //画布
int ns = 10; //画布上一个像素点的实际随机采样数
//相机参数
Point3D lookfrom = new Point3D(1, 0.5f, 1.5f);
Vector3D lookat = new Vector3D(0, 0, 0f);
Camera cam = new Camera(lookfrom, lookat, new Vector3D(0, 1, 0), 60, (double)(nx) / (double)(ny), 0, (lookfrom - lookat).Length(), 0.0, 1.0);
//Camera cam = new Camera();//默认相机参数,使用默认相机，则相机获取射线的函数一样要替换成默认
//遍历画布上的每一点，计算出该点的颜色并画到画布上
for (int i = 0; i < nx; i++)
{
for (int j = 0; j < ny; j++)
{
SColor col = new SColor(); //像素点颜色
for (int s = 0; s < ns; s++) //随机采样，消除锯齿
{
//像素点的每一次采样具体计算
double u = (double)(i + RTUtils.rd.NextDouble()) / (double)nx; //该点在水平方向上的比例
double v = (double)(j + RTUtils.rd.NextDouble()) / (double)ny; //该点在垂直方向上的比例
Ray r = cam.GetRayWith_Time(u, v); //获取从相机到该点的射线（运动+景深）
//Ray r = cam.GetRay(u, v);//获取从相机到该点的射线(默认)
//Ray r = cam.GetRayWith_Time(u, v);//获取从相机到该点的射线（景深）
SColor colTemp = RTUtils.Color(r, world, 0); //采样点颜色值
col = col + colTemp; //采样颜色总和
}
//ns次采样的平均颜色
col = col / ns;
col = new SColor(Math.Sqrt(col.R), Math.Sqrt(col.G), Math.Sqrt(col.B)); //对颜色进行伽马矫正
bitmap.SetPixel(i, ny - j - 1, col.GetColor255()); //画上该点颜色
//设置进度
int pro = (int)((((i + 1) * ny + j) * 100.0) / (nx * ny) + 1);
SetPos(pro);
}
}
string fileneame = "result" + DateTime.Now.Millisecond.ToString() + ".jpeg";
bitmap.Save(fileneame);
//avi_bmps.Add(bitmap);
pictureBox1.Image = bitmap;
textBox1.Text = "渲染时间：" + (DateTime.Now - startTime).ToString();
}
