From: owner-3dui@hitl.washington.edu on behalf of Doug Bowman [bowman@vt.edu] Sent: Friday, December 01, 2000 9:29 AM To: 3dui List Cc: Rex Hartson; Chad Wingrave Subject: RE: notation for 3D interaction techniques Thanks for all of the pointers to prior work, comments, and suggestions. Let me make three points: First, I think I made the issue overly complicated by suggesting that a notation could be used as a basis for implementation. This is true, but not the main focus of my inquiry. We are mostly interested in a description language that is understandable by humans, yet precise and complete, for the purposes of illuminating the subtle details of interaction techniques in lectures and publications. Jeff suggested psuedocode and/or Python. The problem I see with pseudocode is that it's not standardized and can be ambiguous. Ask three computer scientists to write pseudocode for a bubble sort and you'll get three different answers, probably at different levels of detail. I know that Python is used in Alice - Jeff, could you post a simple example of an interaction technique described in Python? Second, I agree with Roy's point that it's probably useful to think about some examples before jumping in to define a language. It's likely that in working through several examples we might find some commonalities. The examples will probably start as pseudocode, but perhaps they can help us to define a specific lexicon/grammar for a 3D IT notation. So, in that spirit, would anyone like to tackle some simple examples? How about: -ray-casting for selection of virtual objects -point-to-fly: point in the direction you want to move -world-in-miniature object manipulation I'll try one of these in a later message. I'd like to see others try them as well. Finally, I just finished talking to my HCI class about using finite state machines as a notation for interaction techniques - has anyone tried this for 3D ITs? Best, Doug -- Doug A. Bowman, Ph.D. (540) 231-7537 Assistant Professor bowman@vt.edu Computer Science www.cs.vt.edu/~bowman/ Virginia Tech