Riccardo Scateni | University of Cagliari (original) (raw)

Papers by Riccardo Scateni

International journal of quantum chemistry, Jun 5, 1992

In this study is presented a general algorithm for computing Voronoi volumes of atoms of group of... more In this study is presented a general algorithm for computing Voronoi volumes of atoms of group of atoms in condensed phases. The method is essentially an extension of the Medvedev procedure to allow vertice determination for any Voronoi polyhedron, primitive or with degenerate vertices. The algorithm has been employed for computing time-averaged volumes in the hydrated crystal of met-myoglobin, using the data of a molecular dynamics simulation. The results, compared to previous volume determination in myoglobin, ...

Abstract The advent of GPGPU technologies has allowed for sensible speed-ups in many high-dimensi... more Abstract The advent of GPGPU technologies has allowed for sensible speed-ups in many high-dimension, memory-intensive computational problems. In this paper we demonstrate the effectiveness of such techniques by describing two applications of GPGPU computing to two different subfields of computer graphics, namely computer vision and mesh processing. In the first case, CUDA technology is employed to accelerate the computation of approximation of motion between two images, known also as optical flow.

Abstract Recently, the number of applications developed for smartphones has dramatically increase... more Abstract Recently, the number of applications developed for smartphones has dramatically increased; however, at the moment, applications having the purpose of creating and displaying 3D models are quite rare. The goal of this work is to build an application that allows the user to see the virtual three-dimensional representations of their friends and interact with them.

ABSTRACT We report on two interactive systems for natural exploration of 3d models. Manipulation ... more ABSTRACT We report on two interactive systems for natural exploration of 3d models. Manipulation and navigation of 3d virtual objects can be a difficult task for a novel user, specially with a common 2D display. With traditional input devices such as 3d mice, trackballs, etc. the interaction doesn't insist directly on the models, but is mediated and not intuitive.

Motion-based segmentation, the problem of detecting rigid parts of an articulated three-dimension... more Motion-based segmentation, the problem of detecting rigid parts of an articulated three-dimensional shape, is an open challenge that has several applications in mesh animation, compression, and interpolation. We present a novel approach that uses the visual perception of the shape and its motion to distinguish the rigid from the deformable parts of the object.

Abstract Natural User Interfaces are often described as familiar, evocative and intuitive, predic... more Abstract Natural User Interfaces are often described as familiar, evocative and intuitive, predictable, based on common skills. Though un-questionable in principle, such definitions don't provide the de-signer with effective means to design a natural interface or evalu-ate a design choice vs another.

Abstract This paper describes the preliminary results obtained using an iterative method for gene... more Abstract This paper describes the preliminary results obtained using an iterative method for generating a set of triangle strips from a mesh of triangles. The algorithm uses a simple topological operation on the dual graph of the mesh, to generate an initial stripification and iteratively rearrange and decrease the number of strips. Our method is a major improvement of a proposed one originally devised for both static and continuous level-of-detail (CLOD) meshes and retains this feature.

abstract={This paper describes the architecture of DiscMC, an interactive system which supports i... more abstract={This paper describes the architecture of DiscMC, an interactive system which supports isosurfacing on regular volume datasets. DiscMC adopts a discretized fitting algorithm that considerably reduces the number of polygons generated by a Marching Cubes-like scheme while presenting shorter running times. The extracted surfaces are composed of polygons lying within a finite number of incidences, thus allowing simple merging of the output facets into large coplanar triangular facets.

Abstract Since the introduction of standard techniques for isosurface extraction from volumetric ... more Abstract Since the introduction of standard techniques for isosurface extraction from volumetric datasets, one of the hardest problems has been to reduce the number of triangles (or polygons) generated. This paper presents an algorithm that considerably reduces the number of polygons generated by a Marching Cubes-like scheme without excessively increasing the overall computational complexity. The algorithm assumes discretization of the dataset space and replaces cell edge interpolation by midpoint selection.

ABSTRACT Frustrated Total Internal Reflection (FTIR) is a key technology for the design of multi-... more ABSTRACT Frustrated Total Internal Reflection (FTIR) is a key technology for the design of multi-touch systems. With respect to other solutions, such as Diffused Illumination (DI) and Diffused Surface Illumination (DSI), FTIR based sensors suffer less from ambient IR noise, and is, thus, more robust to variable lighting conditions. However, FTIR does not provide (or is weak on) some desirable features, such as finger proximity and tracking quick gestures.

Abstract Wall-sized interactive displays gain more and more attention as a valuable tool for mult... more Abstract Wall-sized interactive displays gain more and more attention as a valuable tool for multiuser applications, but typically require the adoption of projectors tiles. Projectors tend to display deformed images, due to lens distortion and/or imperfection, and because they are almost never perfectly aligned to the projection surface. Multi-projector video-walls are typically bounded to the video architecture and to the specific application to be displayed.

Abstract: Merging meshes is a recurrent need in geometry modeling and it is a critical step in th... more Abstract: Merging meshes is a recurrent need in geometry modeling and it is a critical step in the 3D acquisition pipeline, where it is used for building a single mesh from several range scans. A pioneering simple and effective solution to merging is represented by the Zippering algorithm (Turk and Levoy, 1994), which consists of simply stitching the meshes together along their borders.

ABSTRACT In this paper we propose an optimization of the Shape Diameter Function (SDF) that we ca... more ABSTRACT In this paper we propose an optimization of the Shape Diameter Function (SDF) that we call Accelerated SDF (ASDF). We discuss in detail the advantages and disadvantages of the original SDF definition, proposing theoretical and practical approaches for speedup and approximation. Using Poisson-based interpolation we compute the SDF value for a small subset of randomly distributed faces and propagate the values over the mesh.

ABSTRACT In this paper we describe the data structure and some implementation details of the tunn... more ABSTRACT In this paper we describe the data structure and some implementation details of the tunneling algorithm for generating a set of triangle strips from a mesh of triangles. The algorithm uses a simple topological operation on the dual graph of the mesh, to generate an initial stripification and iteratively rearrange and decrease the number of strips. Our method is a major improvement of a proposed one originally devised for both static and continuous level-of-detail (CLOD) meshes and retains this feature.

abstract={The increasing domination of spline-based graphic objects in CAD/CAS has driven a great... more abstract={The increasing domination of spline-based graphic objects in CAD/CAS has driven a great attention to methods focusing on natural and intelligent free-form shape manipulation. We present a novel sketch-based system for the interactive modeling of a variety of free-form 3D objects using just simple spline sketches. Our technique addresses the issue of the traditional illustrations for depicting 3D subjects, ranging from geometric modeling to progressive refinement.

Abstract Shape reconstruction from raw point sets is a hot research topic. Point sets are increas... more Abstract Shape reconstruction from raw point sets is a hot research topic. Point sets are increasingly available as primary input source, since low-cost acquisition methods are largely accessible nowadays, and these sets are more noisy than used to be. Standard reconstruction methods rely on normals or signed distance functions, and thus many methods aim at estimating these features.

ABSTRACT In this paper we present an algorithm of simple implementation but very effective that g... more ABSTRACT In this paper we present an algorithm of simple implementation but very effective that guarantees to keep an optimal stripification (in term of frames per seconds) over a progressive mesh. The algorithm builds on-the-fly the stripification on a mesh at a selected level-of-details (LOD) using the stripifications built, during a pre-processing stage, at the lowest and highest LODs.

Abstract This paper describes the work that has been done during the first year of the 3-SHIRT pr... more Abstract This paper describes the work that has been done during the first year of the 3-SHIRT project, which aims at developing innovative solutions in all the phases of content-based 3D shape retrieval, namely: shape analysis and segmentation, design of shape descriptors, shape indexing and matching, and evaluation. Categories and Subject Descriptors (according to ACM CCS): I. 3.5 [Computer Graphics]: Computational Geometry and Object Modeling; I.

Abstract. We present an application of our time-critical multiresolution rendering algorithm to t... more Abstract. We present an application of our time-critical multiresolution rendering algorithm to the visual and possibly collaborative exploration of large digital mock-ups. Our technique relies upon a scene description in which objects are represented as multiresolution meshes. We perform a constrained optimization at each frame to choose the resolution of each potentially visible object that generates the best quality image while meeting timing constraints.

International journal of quantum chemistry, Jun 5, 1992

In this study is presented a general algorithm for computing Voronoi volumes of atoms of group of... more In this study is presented a general algorithm for computing Voronoi volumes of atoms of group of atoms in condensed phases. The method is essentially an extension of the Medvedev procedure to allow vertice determination for any Voronoi polyhedron, primitive or with degenerate vertices. The algorithm has been employed for computing time-averaged volumes in the hydrated crystal of met-myoglobin, using the data of a molecular dynamics simulation. The results, compared to previous volume determination in myoglobin, ...

Abstract The advent of GPGPU technologies has allowed for sensible speed-ups in many high-dimensi... more Abstract The advent of GPGPU technologies has allowed for sensible speed-ups in many high-dimension, memory-intensive computational problems. In this paper we demonstrate the effectiveness of such techniques by describing two applications of GPGPU computing to two different subfields of computer graphics, namely computer vision and mesh processing. In the first case, CUDA technology is employed to accelerate the computation of approximation of motion between two images, known also as optical flow.

Abstract Recently, the number of applications developed for smartphones has dramatically increase... more Abstract Recently, the number of applications developed for smartphones has dramatically increased; however, at the moment, applications having the purpose of creating and displaying 3D models are quite rare. The goal of this work is to build an application that allows the user to see the virtual three-dimensional representations of their friends and interact with them.

ABSTRACT We report on two interactive systems for natural exploration of 3d models. Manipulation ... more ABSTRACT We report on two interactive systems for natural exploration of 3d models. Manipulation and navigation of 3d virtual objects can be a difficult task for a novel user, specially with a common 2D display. With traditional input devices such as 3d mice, trackballs, etc. the interaction doesn't insist directly on the models, but is mediated and not intuitive.

Motion-based segmentation, the problem of detecting rigid parts of an articulated three-dimension... more Motion-based segmentation, the problem of detecting rigid parts of an articulated three-dimensional shape, is an open challenge that has several applications in mesh animation, compression, and interpolation. We present a novel approach that uses the visual perception of the shape and its motion to distinguish the rigid from the deformable parts of the object.

Abstract Natural User Interfaces are often described as familiar, evocative and intuitive, predic... more Abstract Natural User Interfaces are often described as familiar, evocative and intuitive, predictable, based on common skills. Though un-questionable in principle, such definitions don't provide the de-signer with effective means to design a natural interface or evalu-ate a design choice vs another.

Abstract This paper describes the preliminary results obtained using an iterative method for gene... more Abstract This paper describes the preliminary results obtained using an iterative method for generating a set of triangle strips from a mesh of triangles. The algorithm uses a simple topological operation on the dual graph of the mesh, to generate an initial stripification and iteratively rearrange and decrease the number of strips. Our method is a major improvement of a proposed one originally devised for both static and continuous level-of-detail (CLOD) meshes and retains this feature.

abstract={This paper describes the architecture of DiscMC, an interactive system which supports i... more abstract={This paper describes the architecture of DiscMC, an interactive system which supports isosurfacing on regular volume datasets. DiscMC adopts a discretized fitting algorithm that considerably reduces the number of polygons generated by a Marching Cubes-like scheme while presenting shorter running times. The extracted surfaces are composed of polygons lying within a finite number of incidences, thus allowing simple merging of the output facets into large coplanar triangular facets.

Abstract Since the introduction of standard techniques for isosurface extraction from volumetric ... more Abstract Since the introduction of standard techniques for isosurface extraction from volumetric datasets, one of the hardest problems has been to reduce the number of triangles (or polygons) generated. This paper presents an algorithm that considerably reduces the number of polygons generated by a Marching Cubes-like scheme without excessively increasing the overall computational complexity. The algorithm assumes discretization of the dataset space and replaces cell edge interpolation by midpoint selection.

ABSTRACT Frustrated Total Internal Reflection (FTIR) is a key technology for the design of multi-... more ABSTRACT Frustrated Total Internal Reflection (FTIR) is a key technology for the design of multi-touch systems. With respect to other solutions, such as Diffused Illumination (DI) and Diffused Surface Illumination (DSI), FTIR based sensors suffer less from ambient IR noise, and is, thus, more robust to variable lighting conditions. However, FTIR does not provide (or is weak on) some desirable features, such as finger proximity and tracking quick gestures.

Abstract Wall-sized interactive displays gain more and more attention as a valuable tool for mult... more Abstract Wall-sized interactive displays gain more and more attention as a valuable tool for multiuser applications, but typically require the adoption of projectors tiles. Projectors tend to display deformed images, due to lens distortion and/or imperfection, and because they are almost never perfectly aligned to the projection surface. Multi-projector video-walls are typically bounded to the video architecture and to the specific application to be displayed.

Abstract: Merging meshes is a recurrent need in geometry modeling and it is a critical step in th... more Abstract: Merging meshes is a recurrent need in geometry modeling and it is a critical step in the 3D acquisition pipeline, where it is used for building a single mesh from several range scans. A pioneering simple and effective solution to merging is represented by the Zippering algorithm (Turk and Levoy, 1994), which consists of simply stitching the meshes together along their borders.

ABSTRACT In this paper we propose an optimization of the Shape Diameter Function (SDF) that we ca... more ABSTRACT In this paper we propose an optimization of the Shape Diameter Function (SDF) that we call Accelerated SDF (ASDF). We discuss in detail the advantages and disadvantages of the original SDF definition, proposing theoretical and practical approaches for speedup and approximation. Using Poisson-based interpolation we compute the SDF value for a small subset of randomly distributed faces and propagate the values over the mesh.

ABSTRACT In this paper we describe the data structure and some implementation details of the tunn... more ABSTRACT In this paper we describe the data structure and some implementation details of the tunneling algorithm for generating a set of triangle strips from a mesh of triangles. The algorithm uses a simple topological operation on the dual graph of the mesh, to generate an initial stripification and iteratively rearrange and decrease the number of strips. Our method is a major improvement of a proposed one originally devised for both static and continuous level-of-detail (CLOD) meshes and retains this feature.

abstract={The increasing domination of spline-based graphic objects in CAD/CAS has driven a great... more abstract={The increasing domination of spline-based graphic objects in CAD/CAS has driven a great attention to methods focusing on natural and intelligent free-form shape manipulation. We present a novel sketch-based system for the interactive modeling of a variety of free-form 3D objects using just simple spline sketches. Our technique addresses the issue of the traditional illustrations for depicting 3D subjects, ranging from geometric modeling to progressive refinement.

Abstract Shape reconstruction from raw point sets is a hot research topic. Point sets are increas... more Abstract Shape reconstruction from raw point sets is a hot research topic. Point sets are increasingly available as primary input source, since low-cost acquisition methods are largely accessible nowadays, and these sets are more noisy than used to be. Standard reconstruction methods rely on normals or signed distance functions, and thus many methods aim at estimating these features.

ABSTRACT In this paper we present an algorithm of simple implementation but very effective that g... more ABSTRACT In this paper we present an algorithm of simple implementation but very effective that guarantees to keep an optimal stripification (in term of frames per seconds) over a progressive mesh. The algorithm builds on-the-fly the stripification on a mesh at a selected level-of-details (LOD) using the stripifications built, during a pre-processing stage, at the lowest and highest LODs.

Abstract This paper describes the work that has been done during the first year of the 3-SHIRT pr... more Abstract This paper describes the work that has been done during the first year of the 3-SHIRT project, which aims at developing innovative solutions in all the phases of content-based 3D shape retrieval, namely: shape analysis and segmentation, design of shape descriptors, shape indexing and matching, and evaluation. Categories and Subject Descriptors (according to ACM CCS): I. 3.5 [Computer Graphics]: Computational Geometry and Object Modeling; I.

Abstract. We present an application of our time-critical multiresolution rendering algorithm to t... more Abstract. We present an application of our time-critical multiresolution rendering algorithm to the visual and possibly collaborative exploration of large digital mock-ups. Our technique relies upon a scene description in which objects are represented as multiresolution meshes. We perform a constrained optimization at each frame to choose the resolution of each potentially visible object that generates the best quality image while meeting timing constraints.