Decoupled simulation in virtual reality with the MR toolkit

Abstract

The Virtual Reality (VR) user interface style allows natural hand and body motions to manipulate virtual objects in 3D environments using one or more 3D input devices. This style is best suited to application areas where traditional two-dimensional styles fall short, such as scienti c visualization, architectural visualization, and remote manipulation. Currently, the programming e ort required to produce a VR application is too large, and many pitfalls must be avoided in the creation of successful VR programs. In this paper we describe the Decoupled Simulation Model for creating successful VR applications, and a software system that embodies this model. The MR Toolkit simpli es the development of VR applications by providing standard facilities required by a wide range of VR user interfaces. These facilities include support for distributed computing, head-mounted displays, room geometry management, performance monitoring, hand input devices, and sound feedback. The MR Toolkit encourages programmers to structure their applications to take a d v antage of the distributed computing capabilities of workstation networks improving the application's performance. In this paper, the motivations and the architecture of the toolkit are outlined, the programmer's view is described, and a simple application is brie y described.

A multimodal virtual reality interface for 3D interaction with VTK

“…The VR-vtkRenderWindowInteractor class receives events from this library (instead of from the devices directly), and translates these to VTK-events. It is not much work to modify the VRvtkRenderWindowInteractor class to use other VR libraries, such as the MR toolkit [22] and VRPN [23]. These VR libraries allow us to use VR-VTK on other VR platforms, such as the CAVE.…”

Behavior-friendly graphics

“…Appino et al [1] run such modules on independent computers and use asynchronous communication to avoid round-trip network delays. Shaw et al [15] decouple the application similarly, and in addition allow rendering of the scene independently of the computation of the underlying simulation. Later work addresses the issue of reducing lag in such multiprocessor situations.…”

An object-oriented software architecture for 3D mixed reality applications

“…Most operating systems provide these abstractions for keyboards and mice and other researchers identified the need to have similar abstractions in 3D environments, and so implemented software such as the MR Toolkit [31] and VRPN [35]. Both of these systems are capable of processing trackers, distributing them over a network, and support many types of devices.…”

“…Shaw et al [31] explain how the development of high level software is not possible until there is a stable base of low level toolkits to support them, and this same development process occurred in the 2D desktop area as well. There have been a number of systems that provide low level hardware abstractions and distribution of values over a network, implemented using approximately similar ideas.…”