// todo: improve precision
public static Sphere BoundingSphere(IReadOnlyList <Sphere> spheres)
{
var boundingBox = AaBox.BoundingBox(spheres);
const float normalizedStep = 0.01f;
var scale = Math.Max(Math.Max(boundingBox.HalfSize.Width, boundingBox.HalfSize.Height), boundingBox.HalfSize.Depth);
var step = scale * normalizedStep;
var center = boundingBox.Center;
for (int i = 0; i < 0.25f / normalizedStep; i++)
{
var mostDistantSphere = spheres.Maximal(x => (center - x.Center).Length() + x.Radius);
var towards = mostDistantSphere.Center - center;
var towardsLength = towards.Length();
if (towardsLength > MathHelper.Eps5)
{
center += step * towards / towardsLength;
}
}
var finalMostDistantSphere = spheres.Maximal(x => (center - x.Center).Length() + x.Radius);
return(new Sphere(center, (center - finalMostDistantSphere.Center).Length() + finalMostDistantSphere.Radius));
}
public static Sphere BoundingSphere <T>(IReadOnlyList <T> vertices, Func <T, Vector3> getPosition)
{
var boundingBox = AaBox.BoundingBox(vertices.Select(getPosition));
const float normalizedStep = 0.01f;
var scale = Math.Max(Math.Max(boundingBox.HalfSize.Width, boundingBox.HalfSize.Height), boundingBox.HalfSize.Depth);
var step = scale * normalizedStep;
var center = boundingBox.Center;
for (int i = 0; i < 0.25f / normalizedStep; i++)
{
var mostDistantPoint = vertices.Select(getPosition).Maximal(x => (center - x).LengthSquared());
var towards = mostDistantPoint - center;
var towardsLength = towards.Length();
if (towardsLength > MathHelper.Eps5)
{
center += step * towards / towardsLength;
}
}
var finalMostDistantPoint = vertices.Select(getPosition).Maximal(x => (center - x).LengthSquared());
return(new Sphere(center, (center - finalMostDistantPoint).Length()));
}
public static Sphere BoundingSphere(AaBox box)
{
return(new Sphere(box.Center, box.HalfSize.ToVector().Length()));
}
