/// <summary>
/// Sets this bounding volume to contain the specified volume or to copy from.
/// </summary>
/// <param name="volume">Volume to copy from</param>
public override void Set(BoundingVolume volume)
{
switch (volume.BoundingType)
{
case BoundingType.AABB:
BoundingBox bb = volume as BoundingBox;
m_center = bb.Center;
m_extents = bb.Extents;
return;
case BoundingType.Sphere:
BoundingSphere sphere = volume as BoundingSphere;
m_center = sphere.Center;
float r = sphere.Radius;
m_extents = new Vector3(r, r, r);
return;
case BoundingType.OBB:
OrientedBoundingBox obb = volume as OrientedBoundingBox;
if (!obb.CorrectCorners)
{
obb.ComputeCorners();
}
ComputeFromPoints(obb.Corners);
return;
}
}
/// <summary>
/// Merge takes care of OBB case. Input is the OBB to merge with this
/// AABB to create a merged volume that is stored in the result.
/// </summary>
/// <param name="obb">OrientedBoundingBox to merge with</param>
/// <param name="result">Resulting AABB</param>
private void MergeOBB(OrientedBoundingBox obb, BoundingBox result)
{
if (!obb.CorrectCorners)
{
obb.ComputeCorners();
}
Vector3 min = this.Min;
Vector3 max = this.Max;
for (int i = 0; i < obb.Corners.Length; i++)
{
Vector3 temp = obb.Corners[i];
if (temp.X < min.X)
{
min.X = temp.X;
}
else if (temp.X > max.X)
{
max.X = temp.X;
}
if (temp.Y < min.Y)
{
min.Y = temp.Y;
}
else if (temp.Y > max.Y)
{
max.Y = temp.Y;
}
if (temp.Z < min.Z)
{
min.Z = temp.Z;
}
else if (temp.Z > max.Z)
{
max.Z = temp.Z;
}
}
Vector3 resCenter;
Vector3.Add(ref min, ref max, out resCenter);
Vector3.Multiply(ref resCenter, 0.5f, out resCenter);
Vector3 resExtents;
Vector3.Subtract(ref max, ref m_center, out resExtents);
result.Center = resCenter;
result.Extents = resExtents;
}
/// <summary>
/// Handles the merge case for OBB. Input is the oriented bounding box,
/// which is used with the properties of this Sphere to create a
/// merged volume that is stored in the result.
/// </summary>
/// <param name="obb">Oriented bounding box to merge with</param>
/// <param name="result">Sphere to store the result</param>
private void MergeOBB(OrientedBoundingBox obb, BoundingSphere result)
{
if (!obb.CorrectCorners)
{
obb.ComputeCorners();
}
//Save this sphere's radius/center (result sphere may be this sphere)
float sRad = m_radius;
Vector3 sCenter = m_center;
//Use the input sphere and compute it to contain the OBB's corners
result.ComputeFromPoints(obb.Corners);
//Use our saved radius/center and merge the result sphere with this
result.MergeSphere(ref sRad, ref sCenter, result);
}
