Sketch - Foundation project
Today's 3D modelers allow the specification and display of complex and intricate geometries, but are difficult to use and do not address many of the distinct stages in the design process. In particular, current modeling applications, tailored for precise specification, fail entirely to address the early stages of design when conceptual ideas must be prototyped quickly, but details are intrusive.
The Sketch system [ZELE96] represents a new paradigm in 3D interaction that takes advantage of natural gestural drawing idioms to bridge the gap between hand sketches and computer-based modeling programs. Using Sketch is like drawing with pencil and paper in that only gestures are used (no menus, dialog boxes or buttons). Unlike sketching on paper which produces a static image, the user's hand motions produce a dynamic 3D image.
Users "sketch" objects using familiar graphical conventions for representing 3D, such as three lines sharing a vertex to show the corner of a cube. Because objects in Sketch are defined gesturally, not with numerical input, they may be only approximate models of a final idea. To convey the sense of an informal drawing, Sketch uses a non-photorealistic rendering method that makes models look as if they were drawn by hand instead of a computer. In addition, once learned, the Sketch system is enjoyable to use; a difficult-to-quantify but important factor.
Sketch was enthusiastically received at SIGGRAPH, the premier computer graphics conference. Its success has led to a host of other Center research projects including two-handed interaction [ZELEZ97] and non-photorealistic rendering [MARK97] as well as to corporate funding from Autodesk and SGI's Alias/Wavefront. In addition, a new collaborative Center project combining the gestural sketch paradigm with the Alpha_1 system at Utah is a major component of the all-site telecollaboration project. It will also be used for a multi-Center collaboration on virtual prototyping with the Fraunhofer Center for Research in Computer Graphics.
Interestingly, the inspiration for Sketch came not from the research community or industry but from a Center educational outreach program: Sketch's chief designer, Center staff researcher Bob Zeleznik, participated in a Saturday Academy workshop for inner-city school children and thought he would impress them by demonstrating how real, high-end modeling was done. Trying to explain a CAD interface to children accustomed to crayon and pencil interfaces made Bob acutely aware of the limitations of the WIMP interface style for 3D modeling. This realization led him to research gestural interfaces in order to make computer-based 3D modeling more fluid and more reflective of traditional artistic interfaces.
Full Research Bibliography