Conceptual free-form styling on the responsive workbench

Abstract

A two-handed 3D styling system for fl'ee-form surfaces in a table-like Virtual Environment, the Responsive Workbench (I~WB)TM , is described. Intuitive curve and surface deformation tools based on variational modeling and interaction techniques adapted to 3D V R modeling applications are proposed. The user draws curves (cubic B-splines) directly in the Virtual Environment using a stylus as an inpue device, The era'yes are connected automatically, such that a curve network develops. A combination of automatic and usercontrolled topology extraction modules crea~es the connectivity information. The underlying surface model is based on B-spline surfaces, or, alternatively, uses multisided patches [20] bounded by closed loops of curve pieces. 1, STYLING IN VIRTUAL ENVIRONMENTSMany designers would like sketching free4brm shapes quickly in the conceptual design phase without using a complex CAD system [6]. Projection-based Virtual Environments like the Responsive Workbench (RYVB)TM t [19] offer the following advantages for sketching applications over traditinal desktop interfaces:3.The three-dimensionality of perception in combination with 3D intera.ction gives an immediate understanding of the shape.Regions can be identified, localized, and selected directly in space.The large, high-resolution projection plane enables the representation of objects on a scale which corresponds ~o the working region of both hands.

Drawing on Air: Input Techniques for Controlled 3D Line Illustration

“…Alternative approaches, such as FreeDrawer [9] and Fiorentino et al's stroke segmentation and filtering [10], filter freehand input into smooth spline approximations. Tape drawing-based approaches like ours act as a user driven filter.…”

A general and efficient method for finding cycles in 3D curve networks

“…In a traditional CAD pipeline, engineers start by defining a wireframe of the desired model, which then needs to be turned into a surface representation for analysis, simulation, and manufacturing. More recently, sketching tools [Wesche and Seidel 2001;Bae et al 2008;Schmidt et al 2009;Grimm and Joshi 2012] offer intuitive means for drawing 3D curves using 2D input devices, allowing artists to quickly come up with concept designs. Even though these sketches may not be used for defining the final product, surface visualization could help users better appreciate their design [Abbasinejad et al 2011;Bessmeltsev et al 2012].…”

Real-Time Spatial Surface Modeling System Using Wand Traversal Patterns of Grid Edges

“…3D spatial input was tried on a desktop computer when the 3D output device was not running smoothly [4]. As stereoscopic images and immersive projection environment have become more common, creating geometries through spatial curves [5], gesture input [6] and 3D input wand has been attempted in various ways. Generally, using a 3D spatial input system in a 3D environment with a haptic device enhances approachability to virtual space and alleviates the awareness of the difference inherent in the 3D input interface, enabling more precise input [8].…”