public static SCNMatrix4 ToMatrix4(this SCNQuaternion quaternion)
{
quaternion.Normalize();
nfloat x = quaternion.X;
nfloat y = quaternion.Y;
nfloat z = quaternion.Z;
nfloat w = quaternion.W;
nfloat doubleX = x + x;
nfloat doubleY = y + y;
nfloat doubleZ = z + z;
nfloat doubleW = w + w;
return(new SCNMatrix4(
1.0f - doubleY * y - doubleZ * z,
doubleX * y + doubleW * z,
doubleX * z - doubleW * y,
0.0f,
doubleX * y - doubleW * z,
1.0f - doubleX * x - doubleZ * z,
doubleY * z + doubleW * x,
0.0f,
doubleX * z + doubleW * y,
doubleY * z - doubleW * x,
1.0f - doubleX * x - doubleY * y,
0.0f,
0.0f,
0.0f,
0.0f,
1.0f
));
}
public static SCNQuaternion CreateQuaternion(SCNVector3 v1, SCNVector3 v2)
{
var a = SCNVector3.Cross(v1, v2);
var w = (float)Math.Sqrt(v1.LengthSquared * v2.LengthSquared) + SCNVector3.Dot(v1, v2);
var result = new SCNQuaternion(a.X, a.Y, a.Z, w);
result.Normalize();
return(result);
}
