public static bool TestRaySphere(Ray r, Sphere s)
{
Vector3 m = r.Pos - s.Center;
float c = Vector3.Dot(m, m) - s.Radius * s.Radius;
if (c <= 0.0f)
{
return true;
}
float b = Vector3.Dot(m, r.Dir);
if (b > 0.0f)
{
return false;
}
float disc = b * b - c;
if (disc < 0.0f)
{
return false;
}
return true;
}
public static bool TestRaySphere(Ray r, Sphere s, out float t, out Vector3 q)
{
t = float.MaxValue;
q = new Vector3();
Vector3 m = r.Pos - s.Center;
float b = Vector3.Dot(m, r.Dir);
float c = Vector3.Dot(m, m) - s.Radius * s.Radius;
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 < 0.0f)
{
t = 0.0f;
}
q = r.Pos + r.Dir * t;
return true;
}
public static bool PointInSphere(Vector3 p, Sphere s)
{
return (p - s.Center).LengthSquared() <= s.Radius * s.Radius;
}
