Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883969
Xinguo Liu, H. Bao, Qunsheng Peng, P. Heng, T. Wong, Hanqiu Sun
A novel progressive geometry compression scheme is presented in this paper. In this scheme, a mesh is represented as a base mesh followed by some groups of vertex split operations using an improved simplification method in which each level of the mesh can be refined into the next level by carrying out a group of vertex split operations in any order. Consequently, the progressive mesh (PM) representation can be effectively encoded by permuting the vertex split operations in each group. Meanwhile, a geometry predictor using the Laplacian operator is designed to predict each new vertex position using its neighbours. The correction is quantized and encoded using a Huffman coding scheme. Experimental results show that our algorithm obtains higher compression ratios than previous work. It is very suitable for the progressive transmission of geometric models over the Internet.
{"title":"Progressive geometry compression for meshes","authors":"Xinguo Liu, H. Bao, Qunsheng Peng, P. Heng, T. Wong, Hanqiu Sun","doi":"10.1109/PCCGA.2000.883969","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883969","url":null,"abstract":"A novel progressive geometry compression scheme is presented in this paper. In this scheme, a mesh is represented as a base mesh followed by some groups of vertex split operations using an improved simplification method in which each level of the mesh can be refined into the next level by carrying out a group of vertex split operations in any order. Consequently, the progressive mesh (PM) representation can be effectively encoded by permuting the vertex split operations in each group. Meanwhile, a geometry predictor using the Laplacian operator is designed to predict each new vertex position using its neighbours. The correction is quantized and encoded using a Huffman coding scheme. Experimental results show that our algorithm obtains higher compression ratios than previous work. It is very suitable for the progressive transmission of geometric models over the Internet.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127658080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883967
Lujin Wang, Zesheng Tang
The level-of-detail modeling method is an effective approach for the interactive visualization of complex models. In this paper, we propose a hierarchical tree structure based on the fractal dimension to organize a 3D terrain mesh model and to realize view-dependent continuous level-of-detail rendering of terrain data with a restricted quadtree triangulation method. The total algorithm can be divided into two stages: pre-processing and rendering. In pre-processing, it builds an adaptive hierarchical structure by considering the flatness of the terrain surface evaluated by the fractal dimension. Then it can generate a triangular approximation mesh by dynamically determining preserved data points according to the view-related parameters and performing a restricted quadtree triangulation. Some experiments demonstrate that it is simple and efficient and can be used to support the interactive dynamic rendering of terrain models.
{"title":"View-dependent continuous level-of-detail rendering of terrain model","authors":"Lujin Wang, Zesheng Tang","doi":"10.1109/PCCGA.2000.883967","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883967","url":null,"abstract":"The level-of-detail modeling method is an effective approach for the interactive visualization of complex models. In this paper, we propose a hierarchical tree structure based on the fractal dimension to organize a 3D terrain mesh model and to realize view-dependent continuous level-of-detail rendering of terrain data with a restricted quadtree triangulation method. The total algorithm can be divided into two stages: pre-processing and rendering. In pre-processing, it builds an adaptive hierarchical structure by considering the flatness of the terrain surface evaluated by the fractal dimension. Then it can generate a triangular approximation mesh by dynamically determining preserved data points according to the view-related parameters and performing a restricted quadtree triangulation. Some experiments demonstrate that it is simple and efficient and can be used to support the interactive dynamic rendering of terrain models.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126412576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883936
Hee-Seok Heo, S. Hong, Myung-Soo Kim, G. Elber
Presents an efficient and robust algorithm to compute the intersection curve of two ringed surfaces, each being the sweep /spl cup//sub u/C/sup u/ generated by a moving circle. Given two ringed surfaces /spl cup//sub u/C/sub 1//sup u/ and /spl cup//sub v/C/sub 2//sup v/, we formulate the condition C/sub 1//sup u//spl cap/C/sub 2//sup v//spl ne/O (i.e. that the intersection of the two circles C/sub 1//sup u/ and C/sub 2//sup v/ is non-empty) as a bivariate equation /spl lambda/(u,v)= 0 of relatively low degree. Except for some redundant solutions and degenerate cases, there is a rational map from each solution of /spl lambda/(u,v)=0 to the intersection point C/sub 1//sup u//spl cap/C/sub 2//sup v/. Thus, it is trivial to construct the intersection curve once we have computed the zero-set of /spl lambda/(u,v)=0. We also analyze some exceptional cases and consider how to construct the corresponding intersection curves.
{"title":"The intersection of two ringed surfaces","authors":"Hee-Seok Heo, S. Hong, Myung-Soo Kim, G. Elber","doi":"10.1109/PCCGA.2000.883936","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883936","url":null,"abstract":"Presents an efficient and robust algorithm to compute the intersection curve of two ringed surfaces, each being the sweep /spl cup//sub u/C/sup u/ generated by a moving circle. Given two ringed surfaces /spl cup//sub u/C/sub 1//sup u/ and /spl cup//sub v/C/sub 2//sup v/, we formulate the condition C/sub 1//sup u//spl cap/C/sub 2//sup v//spl ne/O (i.e. that the intersection of the two circles C/sub 1//sup u/ and C/sub 2//sup v/ is non-empty) as a bivariate equation /spl lambda/(u,v)= 0 of relatively low degree. Except for some redundant solutions and degenerate cases, there is a rational map from each solution of /spl lambda/(u,v)=0 to the intersection point C/sub 1//sup u//spl cap/C/sub 2//sup v/. Thus, it is trivial to construct the intersection curve once we have computed the zero-set of /spl lambda/(u,v)=0. We also analyze some exceptional cases and consider how to construct the corresponding intersection curves.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132852413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883979
H. C. Sun, Dimitris N. Metaxas
This paper presents a data-driven procedural model for the kinematic animation of human walking. The use of data yields realistic looking gait, while the procedural model yields flexibility. We present a new motion data representation, the sagittal elevation angles, and present biomechanical evidence that these angles have a stereotyped pattern across many different walking situations, implying their reusability as a motion data source. We also sketch our algorithm for animating human gait based on sagittal elevation angle data, which allows us to generate curved locomotion on uneven terrain with stylistic variation without requiring new datasets.
{"title":"Animation of human locomotion using sagittal elevation angles","authors":"H. C. Sun, Dimitris N. Metaxas","doi":"10.1109/PCCGA.2000.883979","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883979","url":null,"abstract":"This paper presents a data-driven procedural model for the kinematic animation of human walking. The use of data yields realistic looking gait, while the procedural model yields flexibility. We present a new motion data representation, the sagittal elevation angles, and present biomechanical evidence that these angles have a stereotyped pattern across many different walking situations, implying their reusability as a motion data source. We also sketch our algorithm for animating human gait based on sagittal elevation angle data, which allows us to generate curved locomotion on uneven terrain with stylistic variation without requiring new datasets.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129144621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883974
I. Harada, Hidenori Sato, H. Kitazawa
3D object data transfer was optimized to accelerate interactive 3D scene design and virtual-space layout applications. In these applications, downloading many 3D objects reduces the interactivity of the clients. We used level-of-detail based loading sequences and timing control methods to interleave data downloading and interactions. Experiments showed that the maximum interval between interactions was up to 6.42 times shorter.
{"title":"Optimizing network 3D data transmissions for interactive applications","authors":"I. Harada, Hidenori Sato, H. Kitazawa","doi":"10.1109/PCCGA.2000.883974","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883974","url":null,"abstract":"3D object data transfer was optimized to accelerate interactive 3D scene design and virtual-space layout applications. In these applications, downloading many 3D objects reduces the interactivity of the clients. We used level-of-detail based loading sequences and timing control methods to interleave data downloading and interactions. Experiments showed that the maximum interval between interactions was up to 6.42 times shorter.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128312653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883970
Eun Seok Kim, J. Kim
Implicit modeling is an important technique in the modeling of informal objects. However, the available automatic modeling algorithms with implicit skeletal elements are not very advanced. In this paper, we propose a new skeletal element, called a metacube, and an automatic modeling technique for informal objects represented by volumetric data. The metacube has the merits of a metaball and also enhances the modeling ability of informal objects containing planar surfaces. For a 256/spl times/256/spl times/256 size of input volume, the proposed method takes a short generation time (less than ten minutes) on an SGI Indigo 2 workstation.
{"title":"An automatic modeling method for fitting volumetric objects with metacubes","authors":"Eun Seok Kim, J. Kim","doi":"10.1109/PCCGA.2000.883970","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883970","url":null,"abstract":"Implicit modeling is an important technique in the modeling of informal objects. However, the available automatic modeling algorithms with implicit skeletal elements are not very advanced. In this paper, we propose a new skeletal element, called a metacube, and an automatic modeling technique for informal objects represented by volumetric data. The metacube has the merits of a metaball and also enhances the modeling ability of informal objects containing planar surfaces. For a 256/spl times/256/spl times/256 size of input volume, the proposed method takes a short generation time (less than ten minutes) on an SGI Indigo 2 workstation.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128750964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883890
Christian Rössl, L. Kobbelt
We present an interactive system for computer aided generation of line art drawings to illustrate 3D models that are given as triangulated surfaces. In a preprocessing step, an enhanced 2D view of the scene is computed by sampling for every pixel the shading, the normal vectors and the principal directions obtained from discrete curvature analysis. Then streamlines are traced in the 2D direction fields and are used to define line strokes. In order to reduce noise artifacts, the user may interactively select sparse reference lines and the system will automatically fill in additional strokes. By exploiting the special structure of the streamlines, an intuitive and simple tone mapping algorithm can be derived to generate the final rendering.
{"title":"Line-art rendering of 3D-models","authors":"Christian Rössl, L. Kobbelt","doi":"10.1109/PCCGA.2000.883890","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883890","url":null,"abstract":"We present an interactive system for computer aided generation of line art drawings to illustrate 3D models that are given as triangulated surfaces. In a preprocessing step, an enhanced 2D view of the scene is computed by sampling for every pixel the shading, the normal vectors and the principal directions obtained from discrete curvature analysis. Then streamlines are traced in the 2D direction fields and are used to define line strokes. In order to reduce noise artifacts, the user may interactively select sparse reference lines and the system will automatically fill in additional strokes. By exploiting the special structure of the streamlines, an intuitive and simple tone mapping algorithm can be derived to generate the final rendering.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128625511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883951
Mie Sato, I. Bitter, M. A. Bender, A. Kaufman, M. Nakajima
We introduce the TEASAR algorithm which is a treestructure extraction algorithm delivering skeletons that are accurate and robust. Volumetric skeletons are needed for accurate measurements of length along branching and winding structures. Skeletons are also required in automatic virtual navigation, such as traveling through human organs (e.g., the colon) to control movement and orientation of the virtual camera. We introduce a concise but general definition of a skeleton, and provide an algorithm that finds the skeleton accurately and rapidly. Our solution is fully automatic, which frees the user from having to engage in data preprocessing. We present the accurate skeletons computed on a number of test datasets. The algorithm is efficient as demonstrated by the running times on a single 194 MHz MIPS R10000 CPU which were all below five minutes.
{"title":"TEASAR: tree-structure extraction algorithm for accurate and robust skeletons","authors":"Mie Sato, I. Bitter, M. A. Bender, A. Kaufman, M. Nakajima","doi":"10.1109/PCCGA.2000.883951","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883951","url":null,"abstract":"We introduce the TEASAR algorithm which is a treestructure extraction algorithm delivering skeletons that are accurate and robust. Volumetric skeletons are needed for accurate measurements of length along branching and winding structures. Skeletons are also required in automatic virtual navigation, such as traveling through human organs (e.g., the colon) to control movement and orientation of the virtual camera. We introduce a concise but general definition of a skeleton, and provide an algorithm that finds the skeleton accurately and rapidly. Our solution is fully automatic, which frees the user from having to engage in data preprocessing. We present the accurate skeletons computed on a number of test datasets. The algorithm is efficient as demonstrated by the running times on a single 194 MHz MIPS R10000 CPU which were all below five minutes.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127380903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883954
Yong Zhou, A. Toga
This paper discusses voxel-coding for tiling complex volumetric objects with triangular meshes: first choosing cross-sections followed by extracting contours, and then triangulating them according to a given error threshold. The intervals between adjacent cross-sections and for sampling contour points for the tiling operation are determined by the difference in area between contour projections, enabling a relatively small number of triangles to reconstruct the object. Branching problems are solved by introducing a simplified skeleton extracted from the difference region and then finding matched segments of the skeleton for each contour i.e., converting multiple contour connections into a single pair connection. For all major problems involved in reconstruction, voxel-coding provides new and robust solutions. These problems include contour extraction, region filling with arbitrarily complex boundaries for difference region searches, simplified skeleton extraction, contour-skeleton matching, and mapping of curve pairs for contour tiling. The voxel-coding proposed can reconstruct surfaces from complex volumetric objects or contours themselves. The input data may have multiple branches or holes, and is processed in a fully automatic and systematic way. The algorithm is easy to implement, fast to compute and insensitive to abject complexity. This technique is of special importance for bridging discrete volumetric and continuous objects.
{"title":"Voxel-coding for tiling complex volumetric objects","authors":"Yong Zhou, A. Toga","doi":"10.1109/PCCGA.2000.883954","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883954","url":null,"abstract":"This paper discusses voxel-coding for tiling complex volumetric objects with triangular meshes: first choosing cross-sections followed by extracting contours, and then triangulating them according to a given error threshold. The intervals between adjacent cross-sections and for sampling contour points for the tiling operation are determined by the difference in area between contour projections, enabling a relatively small number of triangles to reconstruct the object. Branching problems are solved by introducing a simplified skeleton extracted from the difference region and then finding matched segments of the skeleton for each contour i.e., converting multiple contour connections into a single pair connection. For all major problems involved in reconstruction, voxel-coding provides new and robust solutions. These problems include contour extraction, region filling with arbitrarily complex boundaries for difference region searches, simplified skeleton extraction, contour-skeleton matching, and mapping of curve pairs for contour tiling. The voxel-coding proposed can reconstruct surfaces from complex volumetric objects or contours themselves. The input data may have multiple branches or holes, and is processed in a fully automatic and systematic way. The algorithm is easy to implement, fast to compute and insensitive to abject complexity. This technique is of special importance for bridging discrete volumetric and continuous objects.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122792309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-10-03DOI: 10.1109/PCCGA.2000.883944
H. Seidel
Summary form only given, as follows. Due to their simplicity, triangle meshes are often used to represent geometric surfaces. Their main drawback is the large number of triangles that are required to represent a smooth surface. This problem has been addressed by a large number of mesh simplification algorithms which reduce the number of triangles and approximate the initial mesh. Hierarchical triangle mesh representations provide access to a triangle mesh at a desired resolution, without omitting any information. The article presents an infrastructure for discrete geometry processing, including algorithms for 3D reconstruction, curvature computation, reverse engineering, mesh reduction, interactive multiresolution modeling and progressive transmission of arbitrary unstructured triangle meshes.
{"title":"Efficient processing of large 3D meshes","authors":"H. Seidel","doi":"10.1109/PCCGA.2000.883944","DOIUrl":"https://doi.org/10.1109/PCCGA.2000.883944","url":null,"abstract":"Summary form only given, as follows. Due to their simplicity, triangle meshes are often used to represent geometric surfaces. Their main drawback is the large number of triangles that are required to represent a smooth surface. This problem has been addressed by a large number of mesh simplification algorithms which reduce the number of triangles and approximate the initial mesh. Hierarchical triangle mesh representations provide access to a triangle mesh at a desired resolution, without omitting any information. The article presents an infrastructure for discrete geometry processing, including algorithms for 3D reconstruction, curvature computation, reverse engineering, mesh reduction, interactive multiresolution modeling and progressive transmission of arbitrary unstructured triangle meshes.","PeriodicalId":342067,"journal":{"name":"Proceedings the Eighth Pacific Conference on Computer Graphics and Applications","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117020853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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