/// <summary>
/// Constructs a <see cref="BoundingSphere" /> that fully contains the given points.
/// </summary>
/// <param name="points">The points that will be contained by the sphere.</param>
/// <param name="start">The start index from points array to start compute the bounding sphere.</param>
/// <param name="count">The count of points to process to compute the bounding sphere.</param>
/// <param name="result">When the method completes, contains the newly constructed bounding sphere.</param>
/// <exception cref="System.ArgumentNullException">points</exception>
/// <exception cref="System.ArgumentOutOfRangeException">
/// start
/// or
/// count
/// </exception>
public static void FromPoints(IList <Vector3> points, int start, int count, out global::SharpDX.BoundingSphere result)
{
if (points == null)
{
throw new ArgumentNullException("points");
}
// Check that start is in the correct range
if (start < 0 || start >= points.Count)
{
throw new ArgumentOutOfRangeException("start", start, string.Format("Must be in the range [0, {0}]", points.Count - 1));
}
// Check that count is in the correct range
if (count < 0 || (start + count) > points.Count)
{
throw new ArgumentOutOfRangeException("count", count, string.Format("Must be in the range <= {0}", points.Count));
}
var upperEnd = start + count;
//Find the center of all points.
Vector3 center = Vector3.Zero;
for (int i = start; i < upperEnd; ++i)
{
var p = points[i];
Vector3.Add(ref p, ref center, out center);
}
//This is the center of our sphere.
center /= (float)count;
//Find the radius of the sphere
float radius = 0f;
for (int i = start; i < upperEnd; ++i)
{
//We are doing a relative distance comparison to find the maximum distance
//from the center of our sphere.
float distance;
var p = points[i];
Vector3.DistanceSquared(ref center, ref p, out distance);
if (distance > radius)
{
radius = distance;
}
}
//Find the real distance from the DistanceSquared.
radius = (float)Math.Sqrt(radius);
//Construct the sphere.
result.Center = center;
result.Radius = radius;
}
/// <summary>
/// Constructs a <see cref="BoundingSphere"/> that fully contains the given points.
/// </summary>
/// <param name="points">The points that will be contained by the sphere.</param>
/// <param name="result">When the method completes, contains the newly constructed bounding sphere.</param>
public static void FromPoints(IList <Vector3> points, out global::SharpDX.BoundingSphere result)
{
if (points == null)
{
throw new ArgumentNullException("points");
}
FromPoints(points, 0, points.Count, out result);
}
/// <summary>
/// Transforms the bounding sphere.
/// </summary>
/// <param name="b">The b.</param>
/// <param name="m">The m.</param>
/// <returns></returns>
public static global::SharpDX.BoundingSphere TransformBoundingSphere(this global::SharpDX.BoundingSphere b, Matrix m)
{
var center = b.Center;
var edge = b.Center + Vector3.Right * b.Radius;
var worldCenter = Vector3.Transform(center, m);
var worldEdge = Vector3.Transform(edge, m);
return(new global::SharpDX.BoundingSphere(worldCenter.ToXYZ(), (worldEdge - worldCenter).Length()));
}
public static void TransformBoundingSphere(this global::SharpDX.BoundingSphere b, ref Matrix m, out global::SharpDX.BoundingSphere boundSphere)
{
var center = b.Center;
var edge = b.Center + Vector3.Right * b.Radius;
var worldCenter = Vector3.Transform(center, m);
var worldEdge = Vector3.Transform(edge, m);
boundSphere = new global::SharpDX.BoundingSphere(worldCenter.ToXYZ(), (worldEdge - worldCenter).Length());
}
