/// <summary>
/// Create a rotation and scale.
/// </summary>
static public Matrix4x4f RotateScale(Quaternion3f r, Vector3f s)
{
Matrix4x4f R = r.ToMatrix4x4f();
Matrix4x4f S = Scale(s);
return(R * S);
}
/// <summary>
/// Create a translation and rotation.
/// </summary>
static public Matrix4x4f TranslateRotate(Vector3f t, Quaternion3f r)
{
Matrix4x4f T = Translate(t);
Matrix4x4f R = r.ToMatrix4x4f();
return(T * R);
}
/// <summary>
/// Create a translation, rotation and scale.
/// </summary>
static public Matrix4x4f TranslateRotateScale(Vector3f t, Quaternion3f r, Vector3f s)
{
Matrix4x4f T = Translate(t);
Matrix4x4f R = r.ToMatrix4x4f();
Matrix4x4f S = Scale(s);
return(T * R * S);
}
/// <summary>
/// Are these Quaternions equal.
/// </summary>
public override bool Equals(object obj)
{
if (!(obj is Quaternion3f))
{
return(false);
}
Quaternion3f v = (Quaternion3f)obj;
return(this == v);
}
/// <summary>
/// Slerp the quaternion from the from rotation to the to rotation by t.
/// </summary>
public static Quaternion3f Slerp(Quaternion3f from, Quaternion3f to, float t)
{
if (t <= 0.0f)
{
return(from);
}
else if (t >= 1.0f)
{
return(to);
}
else
{
float cosom = from.x * to.x + from.y * to.y + from.z * to.z + from.w * to.w;
float absCosom = Math.Abs(cosom);
float scale0;
float scale1;
if ((1 - absCosom) > FMath.EPS)
{
float omega = FMath.SafeAcos(absCosom);
float sinom = 1.0f / (float)Math.Sin(omega);
scale0 = (float)Math.Sin((1.0f - t) * omega) * sinom;
scale1 = (float)Math.Sin(t * omega) * sinom;
}
else
{
scale0 = 1 - t;
scale1 = t;
}
Quaternion3f res = new Quaternion3f(scale0 * from.x + scale1 * to.x,
scale0 * from.y + scale1 * to.y,
scale0 * from.z + scale1 * to.z,
scale0 * from.w + scale1 * to.w);
return(res.Normalized);
}
}
/// <summary>
/// Create a rotation out of a vector.
/// </summary>
static public Matrix3x3f Rotate(Vector3f euler)
{
return(Quaternion3f.FromEuler(euler).ToMatrix3x3f());
}
