Abstract
A technique is discussed for the interactive specification and real-time evaluation of the movements of geometrical objects with several degrees of freedom. The technique is a midway between a faithful simulation of the dynamics and kinematics of the object and completely free user control, and as such it is well suited for animated drawings, for example. The method works in two steps: first, the motion of a relevant subobject (the skeleton) is specified interactively in real time. Next, the entire object is deformed and oriented in space such as to match the form of the skeleton. Depending on the complexity of the object, this second step either takes place in real time, or as a batch process. Several forms of geometrical constraints, as well as stretching and squeezing, are supported.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Barzel R, Barr AH (1988) A modeling system based on dynamic constraints. ACM Comput Graphics (Proc SIGGRAPH) 22:179–188
Boehm W, Farin G, Kahman J (1984) A survey of curve and surface methods in CAGD. Computer Aided Geometric Design 1:1–60
Burtnyk N, Wein M (1976) Interactive skeleton techniques for enhancing motion dynamics in key frame animation. Commun ACM 19:564–569
Hahn JK (1988) Realistic animation of rigid bodies. ACM Comput Graph (Proc SIGGRAPH) 22:299–308
Moore M, Wilhelms J (1988) Collision detection and response for computer animation. ACM Comput Graph (Proc SIGGRAPH) 22:289–298
Platt JC, Barr AH (1988) Constraint methods for flexible models. ACM Comput Graph (Proc SIGGRAPH) 22:279–288
Reeves W (1981) Inbetweening for computer animation using moving point constraints. ACM Comput Graph (Proc SIGGRAPH) 15:263–269
Reynolds C (1982) Computer animation with scripts and actors. Comput Graph (Proc SIGGRAPH) 16:289–296
Sneddon IN (ed) (1976) Encyclopaedic dictionary of mathematics for engineers and applied scientists. Glasgow Univ, Pergamon Press, Oxford, pp. 707–709 (and references)
Terzopoulos D, Fleischer K (1988) Modeling inelastic deformation: viscoelasticity, plasticity, fracture. ACM Comput Graph (Proc SIGGRAPH) 22:269–278
Wyvill B (1988) Navigating the animation jungle. Presented at the International Summer Institute: State of the Art in Computer Graphics, Exeter, UK (4–8 July 1988)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
van Overveld, C.W.A.M. A technique for motion specification in computer animation. The Visual Computer 6, 106–116 (1990). https://doi.org/10.1007/BF01901071
Issue Date:
DOI: https://doi.org/10.1007/BF01901071