Faculty of Electrical Engineering and Computer Science
Technical University of Berlin, Germany
http://cg.cs.tu-berlin.de/~marc/
Abstract:
Surface editing operations commonly require geometric details of the surface to be preserved as much as possible. I argue that geometric detail is an intrinsic property of a surface and that, consequently, surface editing is best performed by operating over an intrinsic surface representation. Different ways of representing the intrinsic geometry and the boundary constraints result in alternatives for the properties of the modeling system. In particular, the Laplacian and several extensions are reviewed.
Based on this representation, useful editing operations can be developed:
Interactive free-form deformation in a region of interest
based on the transformation of a handle, transfer and mixing of geometric
detail between two surfaces, and transplanting of a partial
surface mesh into another surface. In particular, the
handle can be a curve such as a silhouette or a sketch on the
surface. Subsequently, an edit can be carried out by
sketching a new, view-dependent handle position or by indirectly
influencing differential properties along the sketch.
The main computation involved in all operations is the solution
of a sparse linear system, which can be done at interactive
rates. We demonstrate the effectiveness of this approach in
several examples, showing that the editing operations change
the shape while respecting the structural geometric detail.
Biography
Marc Alexa is a Professor in the Faculty of Electrical
Engineering and Computer Science at the Technical University
of Berlin and heads the Computer Graphics group. He is
primarily interested in representing shapes and their
deformation, using point sampled geometry, implicit surfaces,
explicit representations, and linear spaces of base shapes.
For his earlier work on morphing he received a PhD in
Computer Science from Darmstadt University of Technology. He has
presented and lectured on topics related to shape representations at
SIGGRAPH and other conferences. Marc Alexa has been a co-chair
and has served as a member of several committees of major
graphics conferences.