private float Trace(Ray ray)
{
// diffuse reflection surface
float color = 0f;
InterResult inter = collider.Collide(ray);
if (inter != null)
{
foreach (Light l in lights)
{
color += l.Sample(inter, collider);
}
}
return(color);
}
public float Sample(InterResult inter, Collider c)
{
Vec3d x = inter.position;
Ray ray = GetRay(x);
InterResult shadow = c.Collide(ray);
if (shadow == null)
{
Vec3d normal = inter.entity.GetNormal(x);
float tmp = normal % ray.direction;
if (tmp > 0)
{
return(luminance * tmp);
}
}
return(0);
}
public InterResult Collide(Ray ray)
{
float t = 100000;
InterResult inter = null;
InterResult tmp;
foreach (Shape entity in world)
{
tmp = entity.Intersect(ray);
if (tmp != null && tmp.t >= 0 && tmp.t < t)
{
t = tmp.t;
inter = tmp;
}
}
return(inter);
}