A method for quick determination of the position and pose of a 3D free-form object with respect to its 2D projective image(s) is proposed. It is a precondition of the method that a 3D model of the object and an initial estimation of the state are given. In [1], we have proposed a 3D-2D registration method for the real-time registration of a 3D model of a cerebral vessel tree to an X-ray image of the vessel taken during an operation. The method is robust and fully automated from raw input image to the result. In this paper, we extend this method to meet a more general purpose. First, the formulae for obtaining the 3D model transformation from 3D-2D point pairs are generalized by describing camera coordinates independently from world coordinates. This enables easy integration of multiple images and simple treatment of moving camera coordinates. The second generalization is to use the occluding contour instead of the skeleton of the blood vessel (tube-like shape) as the feature for matching. To quickly obtain the 3D model points corresponding to the occluding contours in an observed image, we take a 3D graphics system like OpenGL into our 3D-2D registration method. The applicability improvements are shown using two applications: 1) position and pose estimation of a 3D vessel model using multiple views, 2) visual feedback on the position and pose of an active camera head.