Charles F. Rose, B. Guenter, Bobby Bodenheimer, Michael F. Cohen
{"title":"Efficient generation of motion transitions using spacetime constraints","authors":"Charles F. Rose, B. Guenter, Bobby Bodenheimer, Michael F. Cohen","doi":"10.1145/237170.237229","DOIUrl":"https://doi.org/10.1145/237170.237229","url":null,"abstract":"This paper describes the application of space time constraints to creating transitions between segments of human body motion. The motion transition generation uses a combination of spacetime constraints and inverse kinematic constraints to generate seamless and dynamically plausible transitions between motion segments. We use a fast recursive dynamics formulation which makes it possible to use spacetime constraints on systems with many degrees of freedom, such as human figures. The system uses an interpreter of a motion expression language to allow the user to manipulate motion data, break it into pieces, and reassemble it into new, more complex, motions. We have successfully used the system to create basis motions, cyclic data, and seamless motion transitions on a human body model with 44 degrees of freedom. Additional","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133126639","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":"Visual models of plants interacting with their environment","authors":"R. Mech, P. Prusinkiewicz","doi":"10.1145/237170.237279","DOIUrl":"https://doi.org/10.1145/237170.237279","url":null,"abstract":"Interaction with the environment is a key factor affecting the development of plants and plant ecosystems. In this paper we introduce a modeling framework that makes it possible to simulate and visualize a wide range of interactions at the level of plant architecture. This framework extends the formalism of Lindenmayer systems with constructs needed to model bi−directional information exchange between plants and their environment. We illustrate the proposed framework with models and simulations that capture the development of tree branches limited by collisions, the colonizing growth of clonal plants competing for space in favorable areas, the interaction between roots competing for water in the soil, and the competition within and between trees for access to light. Computer animation and visualization techniques make it possible to better understand the modeled processes and lead to realistic images of plants within their environmental context.","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134239480","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":"The virtual cinematographer: a paradigm for automatic real-time camera control and directing","authors":"Li-wei He, Michael F. Cohen, D. Salesin","doi":"10.1145/237170.237259","DOIUrl":"https://doi.org/10.1145/237170.237259","url":null,"abstract":"This paper presents a paradigm for automatically generating complete camera specifications for capturing events in virtual 3D environments in real-time. We describe a fully implemented system, called the Virtual Cinematographer, and demonstrate its application in a virtual \"party\" setting. Cinematographic expertise, in the form of film idioms, is encoded as a set of small hierarchically organized finite state machines. Each idiom is responsible for capturing a particular type of scene, such as three virtual actors conversing or one actor moving across the environment. The idiom selects shot types and the timing of transitions between shots to best communicate events as they unfold. A set of camera modules, shared by the idioms, is responsible for the low-level geometric placement of specific cameras for each shot. The camera modules are also responsible for making subtle changes in the virtual actors? positions to best frame each shot. In this paper, we discuss some basic heuristics of filmmaking and show how these ideas are encoded in the Virtual Cinematographer.","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134353978","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":"Free-form deformations with lattices of arbitrary topology","authors":"Ron MacCracken, K. Joy","doi":"10.1145/237170.237247","DOIUrl":"https://doi.org/10.1145/237170.237247","url":null,"abstract":"A new free-form deformation technique is presented that generalizes previous methods by allowing 3-dimensional deformation lattices of arbitrary topology. The technique uses an extension of the Catmull-Clark subdivision methodology that successively refines a 3-dimensional lattice into a sequence of lattices that converge uniformly to a region of 3-dimensional space. Deformation of the lattice then implicitly defines a deformation of the space. An underlying model can be deformed by establishing positions of the points of the model within the converging sequence of lattices and then tracking the new positions of these points within the deformed sequence of lattices. This technique allows a greater variety of deformable regions to be defined, and thus a broader range of shape deformations can be generated.","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124477142","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}
Jonathan Shade, Dani Lischinski, D. Salesin, T. DeRose, John M. Snyder
{"title":"Hierarchical image caching for accelerated walkthroughs of complex environments","authors":"Jonathan Shade, Dani Lischinski, D. Salesin, T. DeRose, John M. Snyder","doi":"10.1145/237170.237209","DOIUrl":"https://doi.org/10.1145/237170.237209","url":null,"abstract":"We present a new method that utilizes path coherence to accelerate walkthroughs of geometrically complex static scenes. As a preprocessing step, our method constructs a BSP-tree that hierarchically partitions the geometric primitives in the scene. In the course of a walkthrough, images of nodes at various levels of the hierarchy are cached for reuse in subsequent frames. A cached image is reused by texture-mapping it onto a single quadrilateral that is drawn instead of the geometry contained in the corresponding node. Visual artifacts are kept under control by using an error metric that quantifies the discrepancy between the appearance of the geometry contained in a node and the cached image. The new method is shown to achieve speedups of an order of magnitude for walkthroughs of a complex outdoor scene, with little or no loss in rendering quality. CR","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123281770","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":"Flow and changes in appearance","authors":"Julie Dorsey, H. Pedersen, P. Hanrahan","doi":"10.1145/237170.237280","DOIUrl":"https://doi.org/10.1145/237170.237280","url":null,"abstract":"","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127475772","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":"Multiresolution video","authors":"Adam Finkelstein, Charles E. Jacobs, D. Salesin","doi":"10.1145/237170.237266","DOIUrl":"https://doi.org/10.1145/237170.237266","url":null,"abstract":"We present a new representation for time-varying image data that allows for varying—and arbitrarily high—spatial and temporal resolutions in different parts of a video sequence. The representation, called multiresolution video, is based on a sparse, hierarchical encoding of the video data. We describe a number of operations for creating, viewing, and editing multiresolution sequences. These operations support a variety of applications: multiresolution playback, including motion-blurred “fast-forward” and “reverse”; constantspeed display; enhanced video scrubbing; and “video clip-art” editing and compositing. The multiresolution representation requires little storage overhead, and the algorithms using the representation are both simple and efficient. CR","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"63 10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123314672","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":"Improv: a system for scripting interactive actors in virtual worlds","authors":"K. Perlin, Athomas Goldberg","doi":"10.1145/237170.237258","DOIUrl":"https://doi.org/10.1145/237170.237258","url":null,"abstract":"Improv is a system for the creation of real−time behavior−based animated actors. There have been several recent efforts to build network distributed autonomous agents. But in general these efforts do not focus on the author’s view. To create rich interactive worlds inhabited by believable animated actors, authors need the proper tools. Improv provides tools to create actors that respond to users and to each other in real−time, with personalities and moods consistent with the author’s goals and intentions. Improv consists of two subsystems. The first subsystem is an Animation Engine that uses procedural techniques to enable authors to create layered, continuous, non−repetitive motions and smooth transitions between them. The second subsystem is a Behavior Engine that enables authors to create sophisticated rules governing how actors communicate, change, and make decisions. The combined system provides an integrated set of tools for authoring the \"minds\" and \"bodies\" of interactive actors. The system uses an english−style scripting language so that creative experts who are not primarily programmers can create powerful interactive applications.","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114919066","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. Certain, J. Popović, T. DeRose, T. Duchamp, D. Salesin, W. Stuetzle
{"title":"Interactive multiresolution surface viewing","authors":"A. Certain, J. Popović, T. DeRose, T. Duchamp, D. Salesin, W. Stuetzle","doi":"10.1145/237170.237213","DOIUrl":"https://doi.org/10.1145/237170.237213","url":null,"abstract":"Multiresolution analysis has been proposed as a basic tool supporting compression, progressive transmission, and level-of-detail control of complex meshes in a unified and theoretically sound way. We extend previous work on multiresolution analysis of meshes in two ways. First, we show how to perform multiresolution analysis of colored meshes by separately analyzing shape and color. Second, we describe efficient algorithms and data structures that allow us to incrementally construct lower resolution approximations to colored meshes from the geometry and color wavelet coefficients at interactive rates. We have integrated these algorithms in a prototype mesh viewer that supports progressive transmission, dynamic display at a constant frame rate independent of machine characteristics and load, and interactive choice of tradeoff between the amount of detail in geometry and color. The viewer operates as a helper application to Netscape, and can therefore be used to rapidly browse and display complex geometric models stored on the World Wide Web. CR","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133092241","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":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","authors":"","doi":"10.1145/237170","DOIUrl":"https://doi.org/10.1145/237170","url":null,"abstract":"","PeriodicalId":397587,"journal":{"name":"Proceedings of the 23rd annual conference on Computer graphics and interactive techniques","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128176313","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}