/// <summary>
/// 光线追踪测试
/// </summary>
/// <param name="ray"></param>
/// <returns></returns>
public override RayCastResult Intersection(Ray ray, float nowbest)
{
// 包围盒测试失败
{
(bool happened, float mint) = BoundBox.Intersection(ray);
if (!happened || mint > nowbest) // 未相交 或 当前最小解已不是最优
{
return(null);
}
}
RayCastResult result = BVH.Intersection(ray, float.MaxValue);
if (result != null)
{
result.material = Material;
if (result.internalPoint)
{
result.IOR = 1.0f;
}
else
{
result.IOR = Material.Refraction.IOR;
}
}
return(result);
}
public override RayCastResult Intersection(Ray ray, float nowbest)
{
if (ray.OriginObject == this)
{
return(null);
}
{
(bool happened, Float mint) = BoundBox.Intersection(ray);
if (!happened || mint > nowbest) // 未相交 或 当前最小解已不是最优
{
return(null);
}
}
Float u, v, t_tmp = 0;
Vector3f pvec = Vector3f.Cross(ray.Direction, e2); // S1
Float det = Vector3f.Dot(e1, pvec);
Float det_inv = 1.0f / det;
Vector3f tvec = ray.Origin - v0; // S
u = Vector3f.Dot(tvec, pvec) * det_inv;
if (u < 0 || u > 1)
{
return(null);
}
Vector3f qvec = Vector3f.Cross(tvec, e1); // S2
v = Vector3f.Dot(ray.Direction, qvec) * det_inv;
if (v < 0 || u + v > 1)
{
return(null);
}
t_tmp = Vector3f.Dot(e2, qvec) * det_inv;
if (t_tmp < 0)
{
return(null);
}
RayCastResult result = new RayCastResult();
result.distance = t_tmp;
result.obj = this;
result.coords = ray.Origin + t_tmp * ray.Direction;
result.uv = new Vector2f(u, v);
result.normal = Tools.UVMerge(u, v, n0, n1, n2);
result.internalPoint = (Vector3f.Dot(result.normal, ray.Direction) > 0);
if (result.internalPoint)
{
result.normal = -result.normal;
}
return(result);
}
