Parameter-controlled skeletonization: a framework for volume graphics

OF THE THESIS Parameter-Controlled Skeletonization – A Framework for Volume Graphics by Nikhil Gagvani Thesis Director: Professor D. Silver Computer graphics models are typically represented as a collection of polygons or spline patches. Such models only describe the geometry and attributes for the surface of the objects which they represent. Since these models are hollow, interactions which break or deform an object require special consideration. Various natural phenomena like clouds, smoke and water cannot be easily represented using surface based models. An alternative is to use a volumetric representation of objects. Volumetric models can describe the interior properties of objects. These properties can be both physical and optical, which makes it possible to model accurate deformations and light interactions for realistic representation of natural phenomena. Volume graphics focuses on the modeling, manipulation and rendering of volumetric objects. The task of volume modeling, manipulation and deformation is particularly difficult owing to the enormous size of the models. Our research has focused on an efficient abstraction of a volumetric model. We thin the volumetric model into a skeleton using a parameter controlled thinning algorithm. Control of a single thinness parameter allows the skeleton to be represented at various density levels. We then demonstrate the versatility of our multi-scale skeleton for a variety of operations on volumetric models. These operations include deformation, animation,