Surface Trees: Interactive Hierarchical Surface Modeling (papers 0295)

A method is described for representing and manipulating a hierarchy of surface editing operations, in the context of an interactive shape modeling tool. Surface deformations are cast as dynamic geometric textures, applied to locally-parameterized regions of the surface which can be interactively manipulated, and also layered. This use of dynamically layered deformation is characterized as “surface compositing”, and leads to the definition of the surface tree a hierarchical, procedural representation of a 3D surface. Like CSG trees, surface trees allow any deformation to be manipulated at any time. Editing operations higher in the model tree are automatically recomputed, with relative position of layered elements maintained by “anchoring” them in the parameter space of lower layers. In addition to surface deformation, dynamic holes and handles can be created between (possibly non-manifold) surfaces. These techniques are demonstrated in an interactive “drag-and-drop” mesh editing system. To efficiently implement this system, a novel procedural mesh data structure is described. CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Curve, surface, solid, and object representations I.3.6 [Computer Graphics]: Methodology and Techniques—Interaction Techniques