/// <summary>
/// Generates 8 sub bounding octrees inside the boudning node.
/// </summary>
public void CreateOctree()
{
Vector3 size = this.Box.GetSize();
Vector3 half = size / 2.0f;
Vector3 center = this.Box.Min + half;
//Divide boundings into 8 child regions
BoundingNode[] octrees = new BoundingNode[8];
octrees[0] = new BoundingNode(Box.Min, center);
octrees[1] = new BoundingNode(new Vector3(center.X, Box.Min.Y, Box.Min.Z), new Vector3(Box.Max.X, center.Y, center.Z));
octrees[2] = new BoundingNode(new Vector3(center.X, Box.Min.Y, center.Z), new Vector3(Box.Max.X, center.Y, Box.Max.Z));
octrees[3] = new BoundingNode(new Vector3(Box.Min.X, Box.Min.Y, center.Z), new Vector3(center.X, center.Y, Box.Max.Z));
octrees[4] = new BoundingNode(new Vector3(Box.Min.X, center.Y, Box.Min.Z), new Vector3(center.X, Box.Max.Y, center.Z));
octrees[5] = new BoundingNode(new Vector3(center.X, center.Y, Box.Min.Z), new Vector3(Box.Max.X, Box.Max.Y, center.Z));
octrees[6] = new BoundingNode(center, Box.Max);
octrees[7] = new BoundingNode(new Vector3(Box.Min.X, center.Y, center.Z), new Vector3(center.X, Box.Max.Y, Box.Max.Z));
this.Children = octrees.ToList();
}
/// <summary>
/// Determines if the given bounding node is within the current camera Frustum.
/// </summary>
public static bool CheckIntersection(Camera camera, BoundingNode bounding)
{
if (Planes == null)
{
UpdateCamera(camera);
}
//Check sphere detection
var sphereFrustum = ContainsSphere(Planes,
bounding.GetCenter(),
bounding.GetRadius());
switch (sphereFrustum)
{
case Frustum.FULL:
return(true);
case Frustum.NONE: //Check the box anyways atm to be sure
case Frustum.PARTIAL: //Do bounding box detection
var boxFrustum = ContainsBox(Planes, bounding.Box);
if (boxFrustum != Frustum.NONE)
{
return(true);
}
else
{
break;
}
}
foreach (var child in bounding.Children)
{
bool hasIntersection = CheckIntersection(camera, child);
if (hasIntersection)
{
return(true);
}
}
return(false);
}
/// <summary>
/// Checks if a bounding node is within the camera fustrum.
/// </summary>
public bool InFustrum(BoundingNode boundingNode)
{
return(CameraFrustum.CheckIntersection(this, boundingNode));
}
