In this paper, we describe a new method for camera-based fiducial tracking. Our new method is based on the combination of topological region adjacency and angle information, where as related works by Johnston’s RAG target [7], Costanza’s D-Touch [3], and Kaltenbrunner’s reacTIVision [2] are based on the uniqueness of the topological region adjacency structure. Such a combination of the topological region adjacency and angle information enables a wider unique ID range, while maintaining the merit of fast and robust fiducial tracking in topology-based approach. Our method makes it possible to obtain the 6 degrees-of-freedom (6DoF). Such problems of a narrow unique ID range and lack of 6DoF information have been the main deficits in most systems based on topological region adjacency approach, when compared to other fiducial tracking methods. Author Keywords Fiducial tracking, computer vision, tangible interaction, human computer interface. ACM Classification Keywords H.5.2. User In...