“Inkwell: A 2-D animation system” by Litwinowicz

  • ©Peter Litwinowicz




    Inkwell: A 2-D animation system



    Inkwell, an experimental 2 1/2-D keyframe animation system, is the subject of this paper. Inkwell provides an intuitive user interface for creating and animating polygons, ellipses and splines. These primitives may be outlined and filled with a variety of patterns to create animated diagrams, graphs and charts, and simple characters and cartoons. Inkwell also has a patch primitive that facilitates deformation and animation of textured regions. The system provides editing features that include shape and timing control as well as digital filtering of parameters. Finally, Inkwell has deformation primitives that enable an animator to warp geometry in an intuitive manner. Inkwell was used to produce Pigment Promenade, a computer animated short shown at SIGGRAPH 1990.


    1. Baecker, R. “Picture Driven Animation,” Interactive Computer Graphics, edited by Herbert Freeman, IEEE Computer Society, 1980. Originally published in Conference Proceedings, Spring Joint Computer Conference, AFIPS, 1969.]]
    2. Burtnyk, N. and M. Wein. “Computer-Generated Key-Frame Animation.” J. Society Motion Picture and Television Engineers. Vol 80, Number 3, 1971, pp. 149-153.]]
    3. Burtnyk, N. and M. Wein. “Interactive Skeleton Techniques for Enhancing Motion Dynamics in Key Frame Animation,” CACM, Vol 19, Number 10, October 1976.]]
    4. Catmull,E. Tween Users’ Manual. New York: CGL Inc., 1983.]]
    5. Coons, S. Surfaces for Computer-aided Design of Space Forms, M.I.T MAC-TR-41, June 1967.]]
    6. Farin, G. Curves and Surfaces for Computer Aided Geometric Design, A Practical Guide. Second Edition. Academic Press, Inc., 1990.]]
    7. Forrest, A. “On Coons and Other Methods for the Representation of Curved Surfaces,” Computer Graphics and Image Processing, 1, 1972, pp. 341-369.]]
    8. Gomez, J. “TWIXT: A 3D Animation System,” Computers and Graphics, 9, Pergamon Press Ltd., 1985, pp. 291- 298. Originally in Proceedings of Eurographics “84.]]
    9. Honey, F. J., “Computer Animated Episodes by Single-Axis Rotations: CAESAR,” Proceedings of the lOth UAIDE, 1971, pp. 3.210-3.226.]]
    10. Kochanek, D. and R. Barrels. “Interpolating Splines with Local Tension, Continuity and Bias Control,” Computer Graphics, Vol 18, Number 3, July 1984, pp. 33-41.]]
    11. Linton, M., P. Calder and J. Vlissides. “The Design and Implementation of InterViews,” Proceedings of the USENIX C+ + Workshop, November 1987.]]
    12. MacDraw (users’ manual). Apple Computer, Product Number M1509.]]
    13. Oppenheim, A. and R. Schafer. Digital Signal Processing, Prentice-Hall, 1975.]]
    14. Patterson, E., P. Litwinowicz, and N. Greene, “Facial Animation by Spatial Mapping.” Computer Animation 1991.]]
    15. Reeves, W. “lnbetweening for Computer Animation Utilizing Moving Point Constraints,” Computer Graphics, Vol 15, Number 3, August 1981, pp. 263-269.]]
    16. Reynolds, C. “Computer Animation with Scripts and Actors,” Computer Graphics, Vol 16, Number 3, July 1982, pp. 157-166.]]
    17. Sederberg, T. and S. Parry. “Free-Form Deformation of Solid Geometric Models,” Computer Graphics, Vol 20, Number 4, August 1986, pp. 151-160.]]
    18. Steketee, Scott N. and N. Badler. “Parametric Key Frame Interpolation Incorporating Kinetic and Phrasing Control,” Computer Graphics, Vol 19, Number 3, July 1985, pp. 255-262.]]
    19. Sturman, D. “Interactive Keyframe Animation of 3D Articulated Models,” Course notes, SIGGRAPH Course Number 10, Computer Animation: 3D Motion Specification and Control, July 1985, pp. 17-25.]]
    20. Sutherland, I. “Sketchpad: A Man-Machine Graphical Communication System,” MIT Lincoln Laboratory Technical Report, Number 296, January 1963.]]
    21. Witkin, A. and W. Welch. “Fast Animation and Control of Nonrigid Structures,” Computer Graphics, Vol 24, Number 4, August 1990, pp. 243-250.]]

ACM Digital Library Publication: