public override Vec3 GetColorValue(float u, float v, Vec3 p)
{
Vec3 p_N = p.normalize();
double sines = Math.Sin(n * p_N.x) * Math.Sin(n * p_N.y) * Math.Sin(n * p_N.z);//n这个系数越大,格子间距越小.但是这个算法有问题,可能是我传入的p用的问题
if (sines <= 0)
{
return(odd.GetColorValue(u, v, p));
}
else
{
return(even.GetColorValue(u, v, p));
}
}
public static void GetSphereUV(Vec3 p, ref float u, ref float v)
{
//球面坐标投影到uv坐标
p = p.normalize();
//单位球面上坐标可以用θ(theta),φ(phi)两个角度变量表示.theta is the angle down from the pole, and phi is the angle around the axis through the poles,
//比如
//x = cos(phi) cos(theta)
//y = sin(phi) cos(theta)
//z = sin(theta)
//然后uv坐标用这两个角度的话
//u = phi / (2*Pi) phi取值范围[0,2pi]
//v = theta / Pi theta取值范围[0,pi]
double phi = Math.Atan2(p.y, p.x); //取值范围为-π≤θ≤π
double theta = Math.Asin(p.z); //取值范围为-π/2 ≤θ≤π/2
//范围映射下到需要的范围 phi取值范围[0,2pi] theta取值范围[0,pi]
phi += Math.PI;
theta += Math.PI / 2;
//求uv
u = (float)(phi / (2 * Math.PI));
v = (float)(theta / Math.PI);
}
Vec3 u, v, w;//camera coordinate，可能不需要保存
//有时间有心情再把一些特性分离出component吧,一堆参数看着恶心,目前先把功能跑起来
public Camera(Vec3 lookfrom, Vec3 lookat, Vec3 viewup, int _width, int _height, float _distance, float _render_depth, float _aperture, bool _enable_motion_blur)
{
viewpoint = lookfrom;
Vec3 viewdir = lookat - lookfrom;
width = _width;
height = _height;
distance = _distance;
render_depth = _render_depth;
aperture = _aperture;
enable_motion_blur = _enable_motion_blur;
//建立右手系的相机坐标
w = -viewdir.normalize(); //相机的z轴,对于相机往里(往后
u = Vec3.cross(viewup, w).normalize(); //相机的x轴,对于相机水平向右
v = Vec3.cross(w, u).normalize(); //相机的y轴,对于相机水平向上
//按照相机的uvw坐标轴,构建二维像素坐标.[像素屏幕宽width,高height)
pixel_origin = lookfrom - width / 2 * u - height / 2 * v - distance * w;
pixel_horizontal = width * u;
pixel_vertical = height * v;
}