public static bool RayIntersectsSphere(Ray3f ray, Sphere3f sphere, out float t)
{
t = 0;
Vector3f m = ray.Position - sphere.Center;
float b = Vector3f.Dot(m, ray.Direction);
float c = Vector3f.Dot(m, m) - sphere.Radius2;
if (c > 0.0f && b > 0.0f)
{
return(false);
}
float discr = b * b - c;
if (discr < 0.0f)
{
return(false);
}
t = -b - (float)Math.Sqrt(discr);
if (t < 0)
{
t = 0;
}
return(true);
}
public static bool BoxIntersectsCircle(Box3f box, Sphere3f sphere)
{
if (sphere.Center.x - sphere.Radius > box.Max.x ||
sphere.Center.x + sphere.Radius < box.Min.x)
{
return(false);
}
if (sphere.Center.y - sphere.Radius > box.Max.y ||
sphere.Center.y + sphere.Radius < box.Min.y)
{
return(false);
}
if (sphere.Center.z - sphere.Radius > box.Max.z ||
sphere.Center.z + sphere.Radius < box.Min.z)
{
return(false);
}
return(true);
}
public static bool SphereContainsPoint(Sphere3f sphere, Vector3f p)
{
Vector3f diff = p - sphere.Center;
return(diff.SqrMagnitude < sphere.Radius2);
}
