Free-form solid modeling using deformations

Abstract

One of the most important problems of available solid modeling systems is that the range of shapes generated is limited. It is not easy to model objects with free-form surfaces in a conventional solid modeling system. Such objects can be defined arl^itrarily but then operations on them are not transparent and complications occur. A method for achieving free-form effect is to define regular objects or surfaces, then deform them. This keeps various properties of the model intact while achieving the required visuaJ appearance. This thesis explains a number of geometric modeling techniques with deformations applied to them in attempts to combine various approaches developed so far. Regular deformations, which include twisting, bending, and tapering, and free-form deformation technique are combined as a new deformation method. This eliminates some of the disadvantages peculiar to each method and utilizes the advantages of both.