FreeDrawer - A Free-Form Sketching System on the Responsive Workbench

Comments

Franck Norman

Manoj

Summary

The authors of this paper sought to use 3D tools for curve drawing and deformation techniques for curves and surfaces. In their setup, the user draws in a virtual environment, using a tracked stylus as an input device. At a workshop about the needs of designers in virtual environments, the modeler should follow certain guidelines

1. be useful as a combined tool for the conceptual phase up to a certain degree of elaboration
2. hide the mathematical complexity of object representations
3. direct and real time interaction
4. full scale modeling, large working volume
5. be intuitive, easy to learn

Their modeler requires the designer to have some drawing skills, which is not too different from the traditional method. They support direct drawing of space curves and 2D curves, projected onto a virtual plane. The features included in the modeler also includes creating curve networks, changing a curve in a network, filling in the surface, smoothing, sharpening, and dragging curves, sculpting the surface, and creating surface patches. Their interface uses a hand held 3D widget, consisting of a set of virtual pointers starting at the stylus. The pointers will have a specific function like copy, move, delete, smooth, and sharpen. The user will touch the object with the tip of the corresponding pointer and pressing the stylus button afterward. Their user study consisted of one user who had experience with the program before. The user drew a seat.

Discussion

I think this application is okay for the specific area they were going for: the designers. It is understandable that one of the constraints of using the product well was having drawing skills. If this product is catered to the product designers, then those people should already have this skill. I think that the user interface could be better. From what I understand, the user moves the stylus and must touch the proper pointer on the curve. That seems quite difficult especially if there are a lot of curves in the area. Also, they only tested the product on one user. I would like to see some stats on multiple users to see how different designers would do the same task.

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Source: Gerold Wesche and Hans-Peter Seidel. FreeDrawer - A Free-Form Sketching System on the Responsive Workbench. VRST 2001.