Clouds present serious problems to standard computer image generation techniques because clouds do not have well-defined surfaces and boundaries. In addition, clouds contain varying degrees of translucence, and their amorphous structure can change with time. Although several approaches to cloud simulation have produced impressive results, they have relied on complex mathematical models which produce high computation costs for a single image.This paper describes a new approach to cloud simulation using simple planar and curved surfaces whose surface shading and translucence are modulated by a mathematical texturing function. This approach represents the appearance of clouds with enough realism for a wide range of visual simulation but does so at a reasonable computational cost, allowing the generation of sequences of images on small minicomputers. In addition, the cloud model can be constructed in a straightforward manner.
{"title":"Visual simulation of clouds","authors":"G. Gardner","doi":"10.1145/325334.325248","DOIUrl":"https://doi.org/10.1145/325334.325248","url":null,"abstract":"Clouds present serious problems to standard computer image generation techniques because clouds do not have well-defined surfaces and boundaries. In addition, clouds contain varying degrees of translucence, and their amorphous structure can change with time. Although several approaches to cloud simulation have produced impressive results, they have relied on complex mathematical models which produce high computation costs for a single image.This paper describes a new approach to cloud simulation using simple planar and curved surfaces whose surface shading and translucence are modulated by a mathematical texturing function. This approach represents the appearance of clouds with enough realism for a wide range of visual simulation but does so at a reasonable computational cost, allowing the generation of sequences of images on small minicomputers. In addition, the cloud model can be constructed in a straightforward manner.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125721546","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}
Christine Barton, Carl Rosendahl, R. Brandel, Larry Elin, Susan Rugtiv, D. Towey
Issues involved in computer generated video animation will be addressed by the producers of the video and the clients who use the product. The producers of computer generated video include independent production houses and production departments within the television networks. The clients include advertising agencies and the news, sports and entertainment departments of the television networks themselves. Topics to be discussed include design control, equipment used and cost. Issues such as in-house production vs. contracted production and daily production schedules vs. longer term promotional projects will also be discussed.
{"title":"Animated computer graphics in television broadcasting (panel session)","authors":"Christine Barton, Carl Rosendahl, R. Brandel, Larry Elin, Susan Rugtiv, D. Towey","doi":"10.1145/325334.325255","DOIUrl":"https://doi.org/10.1145/325334.325255","url":null,"abstract":"Issues involved in computer generated video animation will be addressed by the producers of the video and the clients who use the product. The producers of computer generated video include independent production houses and production departments within the television networks. The clients include advertising agencies and the news, sports and entertainment departments of the television networks themselves. Topics to be discussed include design control, equipment used and cost. Issues such as in-house production vs. contracted production and daily production schedules vs. longer term promotional projects will also be discussed.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"353 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132343055","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}
The GRaphical INteraction System (GRINS) is described, which integrates an automation-based dialogue controller with a dynamic display model to provide a User Interface Management System. The linkage between the logical device interface and the graphical presentation of virtual devices is discussed. A display manager to support dynamic manipulations of hierarchically structure images is presented. Lastly a model of Display Objects whereby application-specific display objects can have computational constraints defined is described. The constraint system is equivalent to an attributed grammar and is evaluated using an incremental attribute flow algorithm.
{"title":"Input/output linkage in a user interface management system","authors":"D. Olsen, E. P. Dempsey, Roy Rogge","doi":"10.1145/325334.325236","DOIUrl":"https://doi.org/10.1145/325334.325236","url":null,"abstract":"The GRaphical INteraction System (GRINS) is described, which integrates an automation-based dialogue controller with a dynamic display model to provide a User Interface Management System. The linkage between the logical device interface and the graphical presentation of virtual devices is discussed. A display manager to support dynamic manipulations of hierarchically structure images is presented. Lastly a model of Display Objects whereby application-specific display objects can have computational constraints defined is described. The constraint system is equivalent to an attributed grammar and is evaluated using an incremental attribute flow algorithm.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121194694","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}
We describe a method for inferring constraints that are desirable for a given (rough) drawing and then modifying the drawing to satisfy the constraints wherever possible. The method has been implemented as part of an online graphics editor running under the UNIX™ operating system and it has undergone modifications in response to user input. Although the framework we discuss is general, the current implementation is polygon-oriented. The relations examined are: approximate equality of the slope or length of sides, collinearity of sides, and vertical and horizontal alignment of points.
{"title":"An automatic beautifier for drawings and illustrations","authors":"T. Pavlidis, C. V. Wyk","doi":"10.1145/325334.325240","DOIUrl":"https://doi.org/10.1145/325334.325240","url":null,"abstract":"We describe a method for inferring constraints that are desirable for a given (rough) drawing and then modifying the drawing to satisfy the constraints wherever possible. The method has been implemented as part of an online graphics editor running under the UNIX™ operating system and it has undergone modifications in response to user input. Although the framework we discuss is general, the current implementation is polygon-oriented. The relations examined are: approximate equality of the slope or length of sides, collinearity of sides, and vertical and horizontal alignment of points.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121215247","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}
Solid bodies roll and tumble through space. In computer animation, so do cameras. The rotations of these objects are best described using a four coordinate system, quaternions, as is shown in this paper. Of all quaternions, those on the unit sphere are most suitable for animation, but the question of how to construct curves on spheres has not been much explored. This paper gives one answer by presenting a new kind of spline curve, created on a sphere, suitable for smoothly in-betweening (i.e. interpolating) sequences of arbitrary rotations. Both theory and experiment show that the motion generated is smooth and natural, without quirks found in earlier methods.
{"title":"Animating rotation with quaternion curves","authors":"Ken Shoemake","doi":"10.1145/325334.325242","DOIUrl":"https://doi.org/10.1145/325334.325242","url":null,"abstract":"Solid bodies roll and tumble through space. In computer animation, so do cameras. The rotations of these objects are best described using a four coordinate system, quaternions, as is shown in this paper. Of all quaternions, those on the unit sphere are most suitable for animation, but the question of how to construct curves on spheres has not been much explored. This paper gives one answer by presenting a new kind of spline curve, created on a sphere, suitable for smoothly in-betweening (i.e. interpolating) sequences of arbitrary rotations. Both theory and experiment show that the motion generated is smooth and natural, without quirks found in earlier methods.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128704580","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}
A new method for ray tracing parametric surfaces is presented. The new algorithm solves the ray surface intersection directly using multivariate Newton iteration. This provides enough generality to render surfaces which could not be ray traced using existing methods. To overcome the problem of finding a starting point for the Newton algorithm, techniques from Interval Analysis are employed. The results are presented in terms of solving a general nonlinear system of equations f(x)= 0, and thus can be extended to a large class of problems which arise in computer graphics.
{"title":"On ray tracing parametric surfaces","authors":"Dan Toth","doi":"10.1145/325334.325233","DOIUrl":"https://doi.org/10.1145/325334.325233","url":null,"abstract":"A new method for ray tracing parametric surfaces is presented. The new algorithm solves the ray surface intersection directly using multivariate Newton iteration. This provides enough generality to render surfaces which could not be ray traced using existing methods. To overcome the problem of finding a starting point for the Newton algorithm, techniques from Interval Analysis are employed. The results are presented in terms of solving a general nonlinear system of equations f(x)= 0, and thus can be extended to a large class of problems which arise in computer graphics.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125956070","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}
Recently published papers have shown that, with appropriate intersection algorithms, the rendering of many procedural objects is possible with all the advantages offered by the ray-tracing techniques. In the case of stochastic surfaces, the intersection can be computed by a recursive subdivision technique. The efficiency of this algorithm depends essentially on the bounding volume whose size and shape are directly related to the stochastic characteristics of these surfaces. After a brief review of the rendering of stochastic surfaces and the bounding volume selection problem, two types of bounding volume are studied, describing how their intersection with a ray can be computed and how their size can be derived from the stochastic characteristics. The efficiency then, of these bounding volumes are compared.
{"title":"Bounding ellipsoids for ray-fractal intersection","authors":"C. Bouville","doi":"10.1145/325334.325176","DOIUrl":"https://doi.org/10.1145/325334.325176","url":null,"abstract":"Recently published papers have shown that, with appropriate intersection algorithms, the rendering of many procedural objects is possible with all the advantages offered by the ray-tracing techniques. In the case of stochastic surfaces, the intersection can be computed by a recursive subdivision technique. The efficiency of this algorithm depends essentially on the bounding volume whose size and shape are directly related to the stochastic characteristics of these surfaces. After a brief review of the rendering of stochastic surfaces and the bounding volume selection problem, two types of bounding volume are studied, describing how their intersection with a ray can be computed and how their size can be derived from the stochastic characteristics. The efficiency then, of these bounding volumes are compared.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129923944","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}
J. Staudhammer, D. Bailey, S. Dines, L. Doctor, K. Guttag, Jack L. Hancock, Klaus W. Lindenberg, Edmund Y. Sun
The extremely rapid growth of computer graphics is due, in large measure, to the application of leading-edge technology devices. Initially, these devices were not inspired by graphics applications. However, the market has become so large that display oriented semi-conductor devices are becoming specialty product lines. In turn these devices are leading to different display hardware architectures which will profoundly influence emerging capabilities in computer graphics. The future will be shaped as much by these technical innovations as by the economic trends they engender. The panel will examine the forces behind these technological changes and estimate their influence on directions for the computer graphics industry.
{"title":"Computer graphics technology (panel session)","authors":"J. Staudhammer, D. Bailey, S. Dines, L. Doctor, K. Guttag, Jack L. Hancock, Klaus W. Lindenberg, Edmund Y. Sun","doi":"10.1145/325334.325261","DOIUrl":"https://doi.org/10.1145/325334.325261","url":null,"abstract":"The extremely rapid growth of computer graphics is due, in large measure, to the application of leading-edge technology devices. Initially, these devices were not inspired by graphics applications. However, the market has become so large that display oriented semi-conductor devices are becoming specialty product lines. In turn these devices are leading to different display hardware architectures which will profoundly influence emerging capabilities in computer graphics. The future will be shaped as much by these technical innovations as by the economic trends they engender. The panel will examine the forces behind these technological changes and estimate their influence on directions for the computer graphics industry.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128928401","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}
Juno is a system that harmoniously integrates a language for describing pictures with a what-you-see-is-what-you-get image editor. Two of Juno's novelties are that geometric constraints are used to specify locations, and that the text of a Juno program is modified in response to the interactive editing of the displayed image that the program produces.
{"title":"Juno, a constraint-based graphics system","authors":"Greg Nelson","doi":"10.1145/325334.325241","DOIUrl":"https://doi.org/10.1145/325334.325241","url":null,"abstract":"Juno is a system that harmoniously integrates a language for describing pictures with a what-you-see-is-what-you-get image editor. Two of Juno's novelties are that geometric constraints are used to specify locations, and that the text of a Juno program is modified in response to the interactive editing of the displayed image that the program produces.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121408878","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}
P. Malraison, G. Kedem, Greg Lee, Donald J. Meagher
The extremely rapid growth of computer graphics is due, in large measure, to the application of leading-edge technology devices. Initially, these devices were not inspired by graphics applications. However, the market has become so large that display oriented semi-conductor devices are becoming specialty product lines. In turn these devices are leading to different display hardware architectures which will profoundly influence emerging capabilities in computer graphics. The future will be shaped as much by these technical innovations as by the economic trends they engender. The panel will examine the forces behind these technological changes and estimate their influence on directions for the computer graphics industry.
{"title":"Solid modeling with hardware (panel session)","authors":"P. Malraison, G. Kedem, Greg Lee, Donald J. Meagher","doi":"10.1145/325334.325262","DOIUrl":"https://doi.org/10.1145/325334.325262","url":null,"abstract":"The extremely rapid growth of computer graphics is due, in large measure, to the application of leading-edge technology devices. Initially, these devices were not inspired by graphics applications. However, the market has become so large that display oriented semi-conductor devices are becoming specialty product lines. In turn these devices are leading to different display hardware architectures which will profoundly influence emerging capabilities in computer graphics. The future will be shaped as much by these technical innovations as by the economic trends they engender. The panel will examine the forces behind these technological changes and estimate their influence on directions for the computer graphics industry.","PeriodicalId":163416,"journal":{"name":"Proceedings of the 12th annual conference on Computer graphics and interactive techniques","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127298727","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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