This paper proposes a vertex-estimation-based, feature-preserving smoothingtechnique for meshes. A robust mesh smoothing operator called mean value coordinates flow isintroduced to modify mean curvature flow and make ...This paper proposes a vertex-estimation-based, feature-preserving smoothingtechnique for meshes. A robust mesh smoothing operator called mean value coordinates flow isintroduced to modify mean curvature flow and make it more stable. Also the paper proposes athree-pass vertex estimation based on bilateral filtering of local neighbors which is transferredfrom image processing settings and a Quasi-Laplacian operation, derived from the standard Laplacianoperator, is performed to increase the smoothness order of the mesh rapidly whilst denoising meshesefficiently, preventing volume shrinkage as well as preserving sharp features of the mesh. Comparedwith previous algorithms, the result shows it is simple, efficient and robust.展开更多
Efficient parameterization of point-sampled surfaces is a fundamental problem in the field of digital geometry processing. In order to parameterize a given point-sampled surface for minimal distance distortion, a diff...Efficient parameterization of point-sampled surfaces is a fundamental problem in the field of digital geometry processing. In order to parameterize a given point-sampled surface for minimal distance distortion, a differentialslbased segmentation and parameterization approach is proposed in this paper. Our approach partitions the point-sampled geometry based on two criteria： variation of Euclidean distance between sample points, and angular difference between surface differential directions. According to the analysis of normal curvatures for some specified directions, a new projection approach is adopted to estimate the local surface differentials. Then a k-means clustering （k-MC） algorithm is used for partitioning the model into a set of charts based on the estimated local surface attributes. Finally, each chart is parameterized with a statistical method -- multidimensional scaling （MDS） approach, and the parameterization results of all charts form an atlas for compact storage.展开更多
Over the forty-year history of interactive computer graphics, there have beencontinuous advances, but at some stage this progression must terminate with images beingsufficiently realistic for all practical purposes. H...Over the forty-year history of interactive computer graphics, there have beencontinuous advances, but at some stage this progression must terminate with images beingsufficiently realistic for all practical purposes. How much detail do we really need? Polygon countsover a few million imply that on average each polygon paints less than a single pixel, making useof polygon shading hardware wasteful. We consider the problem of determining how much realism isrequired for a variety of applications. We discuss how current trends in computer graphics hardware,and in particular of graphics cards targeted at the computer games industry, will help or hinderachievement of these requirements. With images now being so convincingly realistic in many cases,critical faculties are often suspended and the images are accepted as correct and truthful althoughthey may well be incorrect and sometimes misleading or untruthful. Display resolution has remainedlargely constant in spatial terms for the last twenty years and in terms of the number of pixels hasincreased by less than an order of magnitude. If the long-promised breakthroughs in displaytechnology are finally realised, how should we use the increased resolution?展开更多
文摘This paper proposes a vertex-estimation-based, feature-preserving smoothingtechnique for meshes. A robust mesh smoothing operator called mean value coordinates flow isintroduced to modify mean curvature flow and make it more stable. Also the paper proposes athree-pass vertex estimation based on bilateral filtering of local neighbors which is transferredfrom image processing settings and a Quasi-Laplacian operation, derived from the standard Laplacianoperator, is performed to increase the smoothness order of the mesh rapidly whilst denoising meshesefficiently, preventing volume shrinkage as well as preserving sharp features of the mesh. Comparedwith previous algorithms, the result shows it is simple, efficient and robust.
基金This work is supported by the National Grand Fundamental Research 973 Program of China under Grant No.2002CB312101National Natural Science Foundation of China(NSFC)under Grant Nos. 60503056,60333010the Natural Science Foundation of Zhejiang Province under Grant No.R106449.
文摘Efficient parameterization of point-sampled surfaces is a fundamental problem in the field of digital geometry processing. In order to parameterize a given point-sampled surface for minimal distance distortion, a differentialslbased segmentation and parameterization approach is proposed in this paper. Our approach partitions the point-sampled geometry based on two criteria： variation of Euclidean distance between sample points, and angular difference between surface differential directions. According to the analysis of normal curvatures for some specified directions, a new projection approach is adopted to estimate the local surface differentials. Then a k-means clustering （k-MC） algorithm is used for partitioning the model into a set of charts based on the estimated local surface attributes. Finally, each chart is parameterized with a statistical method -- multidimensional scaling （MDS） approach, and the parameterization results of all charts form an atlas for compact storage.
文摘Over the forty-year history of interactive computer graphics, there have beencontinuous advances, but at some stage this progression must terminate with images beingsufficiently realistic for all practical purposes. How much detail do we really need? Polygon countsover a few million imply that on average each polygon paints less than a single pixel, making useof polygon shading hardware wasteful. We consider the problem of determining how much realism isrequired for a variety of applications. We discuss how current trends in computer graphics hardware,and in particular of graphics cards targeted at the computer games industry, will help or hinderachievement of these requirements. With images now being so convincingly realistic in many cases,critical faculties are often suspended and the images are accepted as correct and truthful althoughthey may well be incorrect and sometimes misleading or untruthful. Display resolution has remainedlargely constant in spatial terms for the last twenty years and in terms of the number of pixels hasincreased by less than an order of magnitude. If the long-promised breakthroughs in displaytechnology are finally realised, how should we use the increased resolution?
