QuickSet: Multimodal Interaction for Distributed Applications Philip R. Cohen, Michael Johnston, David McGee, Sharon Oviatt, Jay Pittman, Ira Smith, Liang Chen and Josh Glow Center for Human Computer Communication Oregon Graduate Institute of Science and Technology

QuickSet: multimodal interaction for distributed applications

This paper introduces a spatial model of interaction which aims to support groups of people in using their natural communication skills in distributed virtual environments. First, we outline our motivation for undertaking this work in terms of the social significance of space in supporting co-operative work. Next, we summarise the model's main concepts, namely aura, awareness, focus, nimbus, adapters and boundaries. Following this, we describe routes to implementing the model. The first is an approach suited to realising the model as an application of existing VR platforms. The second is a general implementation of the model, based on its own specially tailored distributed architecture. Finally, we present our initial observations from use in the laboratory setting and outline issues for future work.2 1 To appear in Proceedings VRST'94, Singapore, August 1994, ACM Press. 2 This work has been funded under the European Commission's ESPRIT programme (the COMIC project) and by the UK's EPSRC.

/pdf/managing-mutual-awareness-in-collaborative-virtual-20udrcbd6w.pdf

Managing mutual awareness in collaborative virtual environments

Navigation tasks in large virtual environments often call for the use of a virtual map. However, all maps are not alike. Performance on navigation tasks in general has been shown to vary depending on the orientation of the map with respect to the user's frame of reference. This paper reports the results of an experiment investigating orientation issues of virtual maps for use during navigation tasks. Participants were given a virtual map in either a north-up or forward-up configuration. Performance on search tasks was measured in terms of search time and errors. Results indicate that targeted search tasks (tasks requiring only the egocentric reference frame) are best served by a forward-up alignment while primed and naive search tasks (tasks requiring information from the world reference frame) prefer a north-up alignment. Both types of maps are affected by the ability of user to perform mental rotations.

Map usage in virtual environments: orientation issues

The Naval Postgraduate School NPS has actively explored the design and implementation of networked, real time, three-dimensional battlefield simulations on low-cost, commercially available graphics workstations. The most recent system, NPSNET, has improved in functionality to such an extent that it is considered a low-cost version of the Defense Advanced Research Project Agency's DARPA SIMNET system. To reach that level, it was necessary to economize in certain areas of the code so that real time performance occurred at an acceptable level. One of those areas was in aircraft dynamics. However, with “off-the-shelf” computers becoming faster and cheaper, real-time and realistic dynamics are no longer an expensive option. Realistic behavior can now be enhanced through the incorporation of an aerodynamic model. To accomplish this task, a prototype flight simulator was built that is capable of simulating numerous types of aircraft simultaneously within a virtual world. Besides being easily incorporated into NPSNET, such a simulator also provides the base functionality for the creation of a general purpose aerodynamic simulator that is particularly useful to aerodynamics students for graphically analyzing differing aircraft's stability and control characteristics. This system is designed for use on a Silicon Graphics workstation and uses the GL libraries. A key feature of the simulator is the use of quaternions for aircraft orientation representation to avoid singularities and high data rates associated with the more common Euler angle representation of orientation.

http://users.encs.concordia.ca/~bwgordon/flight_sim_paper.pdf

Npsnet: Flight simulation dynamic modeling using quaternions

Distributed Open Inventor is an extension to the popular Open Inventor toolkit for interactive 3D graphics. The toolkit is extended with the concept of a distributed shared scene graph, similar to distributed shared memory. From the application programmer's perspective, multiple workstations share a common scene graph. The proposed system introduces a convenient mechanism for writing distributed graphical applications based on a popular tool in an almost transparent manner. Local variations in the scene graph allow for a wide range of possible applications, and local low latency interaction mechanisms called input streams enable high performance while saving the programmer from network peculiarities.

https://www.cg.tuwien.ac.at/research/vr/div/vrst99.pdf

Distributed Open Inventor: a practical approach to distributed 3D graphics

in Computer Graphics, Special Issue on the 1992 Symposium on Interactive 3D Graphics, MIT Media Laboratory, 29 March - 1 April 1992, pp 147-156

/pdf/npsnet-constructing-a-3d-virtual-world-13d6ddvfr3.pdf

NPSNET: constructing a 3D virtual world

NPSOFF: An object description language for supporting virtual world construction

Many virtual world applications today represent the cutting edge in real-time 3D interactive graphics. These applications must model many complex, often changing, graphical objects. These graphical objects must be modeled both visually and behaviorly. An application independent method for describing graphical objects is essential for rapid prototyping and development. This paper presents a simple, flexible and extensible graphics description language, NPSGDL, used in virtual world development at the Naval Postgraduate School.

https://calhoun.nps.edu/bitstream/10945/41553/1/Eurographcs92.pdf

Kalin P. Wilson

Papers

NPSNET: constructing a 3D virtual world

NPSOFF: An object description language for supporting virtual world construction

NPSGDL: An Object Oriented Graphics Description Language for Virtual World Application Support

Educational and technological foundations for the construction of a 3D virtual world