{"title":"3D modeling with silhouettes","authors":"Alec R. Rivers, F. Durand, T. Igarashi","doi":"10.1145/1833349.1778846","DOIUrl":"https://doi.org/10.1145/1833349.1778846","url":null,"abstract":"We present a new sketch-based modeling approach in which models are interactively designed by drawing their 2D silhouettes from different views. The core idea of our paper is to limit the input to 2D silhouettes, removing the need to explicitly create or position 3D elements. Arbitrarily complex models can be constructed by assembling them out of parts defined by their silhouettes, which can be combined using CSG operations. We introduce a new simplified algorithm to compute CSG solids that leverages special properties of silhouette cylinders to convert the 3D CSG problem into one that can be handled entirely with 2D operations, making implementation simpler and more robust. We evaluate our approach by modeling a random sampling of man-made objects taken from the words in WordNet, and show that all of the tested man-made objects can be modeled quickly and easily using our approach.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133373760","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}
{"title":"Toward evaluating material design interface paradigms for novice users","authors":"W. B. Kerr, F. Pellacini","doi":"10.1145/1833349.1778772","DOIUrl":"https://doi.org/10.1145/1833349.1778772","url":null,"abstract":"Material design is the process by which artists specify the reflectance properties of a surface, such as its diffuse color and specular roughness. We present a user study to evaluate the relative benefits of different material design interfaces, focusing on novice users since they stand to gain the most from intuitive interfaces. Specifically, we investigate the editing of the parameters of analytic bidirectional distribution functions (BRDFs) using three interface paradigms: physical sliders by which users set the parameters of analytic BRDF models, such as diffuse albedo and specular roughness; perceptual sliders by which users set perceptually-inspired parameters, such as diffuse luminance and gloss contrast; and image navigation by which material variations are displayed in arrays of image thumbnails and users make edits by selecting them. We investigate two design tasks: precise adjustment and artistic exploration. We collect objective and subjective data, finding that subjects can perform equally well with physical and perceptual sliders as long as the interface responds interactively. Image navigation performs worse than the other interfaces on precise adjustment tasks, but excels at aiding in artistic exploration. We find that given enough time, novices can perform relatively complex material editing tasks with little training, and most novices work similarly to one another.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134336513","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}
K. Fatahalian, S. Boulos, James Hegarty, K. Akeley, W. Mark, Henry P. Moreton, P. Hanrahan
{"title":"Reducing shading on GPUs using quad-fragment merging","authors":"K. Fatahalian, S. Boulos, James Hegarty, K. Akeley, W. Mark, Henry P. Moreton, P. Hanrahan","doi":"10.1145/1833349.1778804","DOIUrl":"https://doi.org/10.1145/1833349.1778804","url":null,"abstract":"Current GPUs perform a significant amount of redundant shading when surfaces are tessellated into small triangles. We address this inefficiency by augmenting the GPU pipeline to gather and merge rasterized fragments from adjacent triangles in a mesh. This approach has minimal impact on output image quality, is amenable to implementation in fixed-function hardware, and, when rendering pixel-sized triangles, requires only a small amount of buffering to reduce overall pipeline shading work by a factor of eight. We find that a fragment-shading pipeline with this optimization is competitive with the REYES pipeline approach of shading at micropolygon vertices and, in cases of complex occlusion, can perform up to two times less shading work.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129553187","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}
N. Mitra, Yong-Liang Yang, Dong‐Ming Yan, Wilmot Li, Maneesh Agrawala
{"title":"Illustrating how mechanical assemblies work","authors":"N. Mitra, Yong-Liang Yang, Dong‐Ming Yan, Wilmot Li, Maneesh Agrawala","doi":"10.1145/1833349.1778795","DOIUrl":"https://doi.org/10.1145/1833349.1778795","url":null,"abstract":"How things work visualizations use a variety of visual techniques to depict the operation of complex mechanical assemblies. We present an automated approach for generating such visualizations. Starting with a 3D CAD model of an assembly, we first infer the motions of individual parts and the interactions between parts based on their geometry and a few user specified constraints. We then use this information to generate visualizations that incorporate motion arrows, frame sequences and animation to convey the causal chain of motions and mechanical interactions between parts. We present results for a wide variety of assemblies.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124650217","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}
{"title":"Micropolygon ray tracing with defocus and motion blur","authors":"Qiming Hou, Hao Qin, Wenyao Li, B. Guo, Kun Zhou","doi":"10.1145/1833349.1778801","DOIUrl":"https://doi.org/10.1145/1833349.1778801","url":null,"abstract":"We present a micropolygon ray tracing algorithm that is capable of efficiently rendering high quality defocus and motion blur effects. A key component of our algorithm is a BVH (bounding volume hierarchy) based on 4D hyper-trapezoids that project into 3D OBBs (oriented bounding boxes) in spatial dimensions. This acceleration structure is able to provide tight bounding volumes for scene geometries, and is thus efficient in pruning intersection tests during ray traversal. More importantly, it can exploit the natural coherence on the time dimension in motion blurred scenes. The structure can be quickly constructed by utilizing the micropolygon grids generated during micropolygon tessellation. Ray tracing of defocused and motion blurred scenes is efficiently performed by traversing the structure. Both the BVH construction and ray traversal are easily implemented on GPUs and integrated into a GPU-based micropolygon renderer. In our experiments, our ray tracer performs up to an order of magnitude faster than the state-of-art rasterizers while consistently delivering an image quality equivalent to a maximum-quality rasterizer. We also demonstrate that the ray tracing algorithm can be extended to handle a variety of effects, such as secondary ray effects and transparency.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120947304","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}
{"title":"Rigid-body fracture sound with precomputed soundbanks","authors":"Changxi Zheng, Doug L. James","doi":"10.1145/1833349.1778806","DOIUrl":"https://doi.org/10.1145/1833349.1778806","url":null,"abstract":"We propose a physically based algorithm for synthesizing sounds synchronized with brittle fracture animations. Motivated by laboratory experiments, we approximate brittle fracture sounds using time-varying rigid-body sound models. We extend methods for fracturing rigid materials by proposing a fast quasistatic stress solver to resolve near-audio-rate fracture events, energy-based fracture pattern modeling and estimation of \"crack\"-related fracture impulses. Multipole radiation models provide scalable sound radiation for complex debris and level of detail control. To reduce soundmodel generation costs for complex fracture debris, we propose Precomputed Rigid-Body Soundbanks comprised of precomputed ellipsoidal sound proxies. Examples and experiments are presented that demonstrate plausible and affordable brittle fracture sounds.","PeriodicalId":132490,"journal":{"name":"ACM SIGGRAPH 2010 papers","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114899303","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}