Background

Contract professor of 'Computer Graphics' with the School of Engineering, University of Roma Tre, in academic year 2006/2007. Senior research associate with the CAD Lab at Department of Informatica e Automazione since 2003. Graduated in Computer Engineering 'summa cum laude' at University Roma Tre in October 2000. Foreign Computer Scientist and Researcher with CASC (Center for Applied Scientific Computing) at LLNL (Lawrence Livermore National Laboratory, DoE, USA) in 2002, 2003 and 2005. Visiting scholar in 2001 with the Dept. of Computer Science (Prof. Bernd Hamann) of the University of California at Davis. 3rd Award of OpenCascade Developer Challenge 2000. Author of 8 publications on international peer-reviewed journals and conferences, including ACM Siggraph 2007 and International Journal of Computational Geometry and Applications. Consultant with ......

Projects

Didattica 2008. Ing. Civile


Corso di Applicazioni progettuali di grafica computerizzata  



   Introduzione
   Trasformazioni affini
   Primitive grafiche
   Rendering grafico




Siggraph 2007 Paper


Robust On-line Computation of Reeb Graphs: Simplicity and Speed  Link



Reeb graphs are a fundamental data structure for understanding and representing the topology of shapes. They are used in computer graphics, solid modeling, and visualization for applications ranging from the computation of similarities and finding defects in complex models to the automatic selection of visualization parameters.....

V. Pascucci, G. Scorzelli, P.-T. Bremer, and A. Mascarenhas,
ACM Transactions on graphics to appear,
Proceedings of SIGGRAPH 2007

PDF paper Paper. Abstract Abstract.

Video1 Find undesired tunnels in a 3D model using the Reeb graph (106MB video).

Video2 Reeb graph of a running horse (7.7MB video).



Computer-Aided Design and Applications 2006


C. Bajaj, A. Paoluzzi and G. Scorzelli,
Progressive conversion from B-rep to BSP for streaming geometric modeling.
Computer-Aided Design and Applications, Vol. 3, Nos. 5 (6), 2006.
Link



We introduce a novel progressive approach to generate a Binary Space Partition (BSP ) and convex cell decomposition from any input triangles boundary representation (B-rep), by utilizing a very fast computation of the surface inertia. A solid model is so generated at progressive levels of detail. This approach relies on a simple variation of standard BSP trees, allowing for labeling cells as in, out and fuzzy, and permits a complete r epresentation of a solid mesh as the Hasse diagram of a cell complex. Our new algorithm is embedded in a streamlined computational framework using four types of dataflow processes, that continuously produce, transform, combine or consume subsets of cells depending on the number or their input/output streams. A varied collection of geometric modeling techniques are integrated in this streaming framework, including polygonal, spline, solid and heterogeneous modeling with boundary and decompositive representations, Boolean set operations, Cartesian products and adaptive refinement. The real-time B-rep to BSP streaming results we report in this paper are a large step towards the unification of rapid conceptual and detailed shape design methodologies.



Didattica


Corso di informatica grafica  Link



INFORMATICA GRAFICA SSD ING-INF/05 Sistemi di elaborazione delle informazioni a.a. 2007/2008


















Research project in scientific visualization at LLNL


Contour Trees and Reeb Graphs   Link



The Contour Tree of a scalar field is the graph obtained by contracting all the connected components of the level sets of the field into points. This is a powerful abstraction for representing the structure of the field with explicit description of the topological changes of its level sets. It has proven effective as a data-structure for fast extraction of isosurfaces and its application has been advocated as a user interface component guiding interactive data exploration sessions. In practice, this use has been very limited due the problem of presenting a graph that may be overwhelming in size and in which a planar embedding may be confusing due to self-intersections. Topological simplification techniques have helped in relieving this. problem since they allow reducing the size of the graph. We present a multi-resolution data-structure for representing contour trees and an algorithm for its construction. Moreover, we provide a hierarchical layout that allows coarse-to-fine rendering of the tree in a progressive user interface. Construction of our multi-resolution model is only slightly more expensive than the standard tree, but introduces far greater flexibility when filtering, both uniformly and adaptively, the topology of the data by importance with respect to different metrics. We have tested the approach using topological persistence (that is the difference in function value between a pair of critical points that are simplified) as the main metric for constructing the topological hierarchy, and using geometric position (containment in a bounding box) as a secondary metric for adaptive refinement.



PLM Group, UniversitÓ di Roma Tre


Progressive binary partitioning trees   Link



In this project I introduce a dataflow pipeline for modeling complex geometric shapes. A pipelined dataflow was always used in graphics rendering engines; its use for modeling is very new. I use balanced BSP trees as progressive representations of shapes with multiple levels of detail. Streaming Boolean operations produce coarse approximations of the output, which is instantly visualized and continuously improved as the input is read. View-dependent data are propagated upstream to the modeling pipeline so that the computation is focused on resolving the model features currently of interest for the user. While I use specialized routines to generate primitive objects, such as spheres and cylinders, I show how the scheme adapts well to subdivision models and use them to construct progressive BSP representations to refine on demand only where and when needed. I also introduce an algorithm for converting spline surfaces to balanced BSPs suitable for interactive modeling within our progressive pipeline, and demonstrate the effectiveness of the approach with a set of examples from our prototype.



Research project in scientific visualization at LLNL


Visus   Link



A Research Project in Scientific Visualization centered on the development of cache oblivious approaches for the management, streaming and rendering of large surface and volume meshes. Principal Investigator: Valerio Pascucci. In the ViSUS project (see the featured article in the LDRD report) we develop data streaming techniques for progressive processing and visualization of large scientific datasets. Our strategy is to exploit the coupling between time-critical algorithms and progressive multi-resolution data-structures to realize an end-to-end optimized flow of data from the original source, such as remote storage or large scientific simulation, to the rendering hardware. The implementation of this approach will enable three major visualization modalities. (i) Interactive visualization on high resolution power-walls. (ii) Interactive visualization on desktop workstations of large datasets that cannot be stored locally. (iii) Immediate monitoring of remote simulations from a desktop workstation. These modalities target multiple phases in the process of generating and exploring very large simulation datasets where real-time user interaction can increase the productivity of scientists.



PLM Group, UniversitÓ di Roma Tre


The integration of geometric kernels in a functional language  Link



CScheme is an application developed at "UniversitÓ of Roma Tre" (Rome, Italy) for my computer science thesis. CScheme provides the integration of of two open-source software projects: OpenCascade which is a powerful geometric and graphics environment mainly written in C++; and Mzscheme which is a first-class platform-independent implementation of the functional language Scheme by Programming Language Team (PLT) of Rice University. The integration has been achieved by a Foreign Function Interface which acts as a wrapper between a functional environment and a C++ low-level library for solid modeling.



PLM Group, UniversitÓ di Roma Tre


Programming LAnguage for Solid Modeling: MzPlasm   Link



PLaSM, (the Programming LAnguage for Solid Modeling) is a ``design language", developed by the CAD Group at the Universities of Roma ``La Sapienza" and ``Roma Tre". Among the strong points of PLaSM: (i) the functional approach which allows to compute geometries with numbers and functions (ii) the dimension-independent implementation of geometric data structures and algorithms. The "classic" PLaSM was implemented in Common Lisp. The MzPlasm prototype currently under development is instead written in Scheme, both for the greater simplicity and elegance of its syntax and semantics, and for the availability of a first-class platform-independent public-domain implementation from Rice University.





PLM Group, UniversitÓ di Roma Tre


OpenGL lessons   Link



OpenGL lessons (Only italian version) for the Computer Graphic course (2004) at University of Roma Tre, DIA department .








Total Management
  • design by:
  • Giorgio Scorzelli