XNA: get Vector3 from Matrix

Question

I thought I understood matrix math well enough, but apparently I'm clueless

Here's the setup:

I have an object at [0,0,0] in world space. I have a camera class controlled by mouse movements to rotate and zoom around the object such that it always looks at it. Here is how I calculate my viewMatrix from the camera:

public Matrix viewMatrix { 
    get {
        return 
            Matrix.CreateFromAxisAngle(Vector3.Up, rotAngle)
                * Matrix.CreateFromAxisAngle(Vector3.Left, pitchAngle)
                * Matrix.CreateTranslation(0, 0, distance) 
        ;
    }
}

I need to be able to get the position of the camera in world space so I can get its distance from the box--particularly its distance from each face of the box. How can I get the camera's xyz position in world space coords?

I've tried:

// all of these only return [0, 0, distance];
Vector3 pos = Vector3.Transform(Vector3.Zero, viewMatrix);
Vector3 pos = viewMatrix.Translation;
Vector3 pos = new Vector3(viewMatrix.M41, viewMatrix.M42, viewMatrix.M43);

It seems like the rotation information is being lost somehow. The strange thing is that the viewMatrix code works perfectly for positioning the camera!

Answer 1

or to simplify slightly:

Vector3 pos = Matrix.Invert(view).Translation;