public override bool BoundingBox(double t0, double t1, ref AABB box)
{
if (!Object.BoundingBox(t0, t1, ref box))
{
return(false);
}
box = new AABB(box.min + offset, box.max + offset);
return(true);
}
public RotateY(Hitable p, double angle)
{
Object = p;
double radians = (Math.PI / 180f) * angle;
sin_theta = Math.Sin(radians);
cos_theta = Math.Cos(radians);
hasbox = Object.BoundingBox(0, 1, ref bbox);
Vector3D min = new Vector3D(double.MaxValue, double.MaxValue, double.MaxValue);
Vector3D max = new Vector3D(-double.MaxValue, -double.MaxValue, -double.MaxValue);
for (int i = 0; i < 2; i++)
{
for (int j = 0; j < 2; j++)
{
for (int k = 0; k < 2; k++)
{
double x = i * bbox.max.X + (1 - i) * bbox.min.X;
double y = j * bbox.max.Y + (1 - j) * bbox.min.Y;
double z = k * bbox.max.Z + (1 - k) * bbox.min.Z;
double newx = cos_theta * x + sin_theta * z;
double newz = -sin_theta * x + cos_theta * z;
Vector3D tester = new Vector3D(newx, y, newz);
for (int c = 0; c < 3; c++)
{
if (tester[c] > max[c])
{
max[c] = tester[c];
}
if (tester[c] < min[c])
{
min[c] = tester[c];
}
}
}
}
}
bbox = new AABB(min, max);
}
public override bool BoundingBox(double t0, double t1, ref AABB box)
{
return(boundary.BoundingBox(t0, t1, ref box));
}
public BVHNode(Hitable[] p, int n, double time0, double time1)
{
//用来排序的嵌套函数
int Compare(Hitable a, Hitable b, int i)
{
AABB l = new AABB(), r = new AABB();
if (!a.BoundingBox(0, 0, ref l) || !b.BoundingBox(0, 0, ref r))
{
throw new Exception("NULL");
}
return(l.min[i] - r.min[i] < 0 ? -1 : 1);
}
//用来排序的分割数组的嵌套函数
Hitable[] SplitArray(Hitable[] Source, int StartIndex, int EndIndex)
{
Hitable[] result = new Hitable[EndIndex - StartIndex + 1];
for (int i = 0; i <= EndIndex - StartIndex; i++)
{
result[i] = Source[i + StartIndex];
}
return(result);
}
//随机一个轴，x轴:0 y轴:1 z轴:3
int method = (int)(3 * Mathematics.Random.Get());
//转换为List然后使用排序,最后再转换会Array
//排序规则使用lambda表达式转向比较函数，并加入轴向参数
List <Hitable> temp_list = p.ToList();
temp_list.Sort((a, b) => Compare(a, b, method));
p = temp_list.ToArray();
//检测当前子节点数量，如果大于2则继续分割
switch (n)
{
case 1:
left = right = p[0];
break;
case 2:
left = p[0];
right = p[1];
break;
default: //拆分
left = new BVHNode(SplitArray(p, 0, n / 2 - 1), n / 2, time0, time1);
right = new BVHNode(SplitArray(p, n / 2, n - 1), n - n / 2, time0, time1);
break;
}
//根据子节点生成当前节点的包围盒
AABB box_left = new AABB(), box_right = new AABB();
if (!left.BoundingBox(time0, time1, ref box_left) || !right.BoundingBox(time0, time1, ref box_right))
{
throw new Exception("no bounding box in bvh_node constructor");
}
box = GetBox(box_left, box_right);
if (n == 6)
{
Console.WriteLine("结果" + this);
}
}