VOLUMETRIC MODELING OF NATURAL OBJECTS WITH COMPACT AND CONSISTENT REPRESENTATIONS

Modeling of 3D objects ' internal information, or volumetric modeling, is useful for various computer graphics applications. For example, volumetric information would enable a rich set of natural and intuitive interactions with 3D models such as cutting and peeling. Volumetric information would also be important for applications such as rendering of heterogeneous translucent objects and simulation of heterogeneous deformable objects. Our goal in this thesis is to allow the user to interactively create volumetric models of natural objects such as vegetables, fruit, and organs that contain complex internal structures. In particular, we aim at providing the user with efficient and intuitive modeling user interfaces while achieving compact and consistent representations. Volumetric modeling is fundamentally difficult mainly because of two reasons. First, we cannot perceive volumetric information directly; hence it is difficult for a user to specify vol-umetric information directly. Second, computational cost in volumetric modeling can often become prohibitively large. We propose two general principles to deal with these two diffi-culties. To deal with the rst difficulty, we propose to let the user specify information suc