The Display Protocol. A Reference for the Protocol

The Display Protocol is a unified graphics system for use at IIASA. It is based on existing systems to some extent. It consists of a device independent protocol interpreter and a small set of device dependent routines. Adapting it to a wide range of output devices requires little programmer effort. It is different from most existing systems in that it also handles devices with no graphics capability. It can convey both textual and graphic data in the same character stream. For a more detailed discussion of the design decisions that lead to the current Display Protocol see PP-79-1, "A Network Compatible Display Protocol", by B. Schweeger. Other design goals include having a clean user input side interface, meshing with UNIX design philosophy, containing ASCII as a subset, and being compact for efficient transmission over networks. This document describes the Display Protocol as it stands, not as it might be, and so may be out of date on some subjects. However, most revisions of the protocol are expected to be backward compatible. While this document may not represent what is latest with the Display Protocol, it should serve the applications writer adequately

DIVERSE: a Software Toolkit to Integrate Distributed Simulations with Heterogeneous Virtual Environments

We present DIVERSE (Device Independent Virtual Environments- Reconfigurable, Scalable, Extensible), which is a modular collection of complimentary software packages that we have developed to facilitate the creation of distributed operator-in-the-loop simulations. In DIVERSE we introduce a novel implementation of remote shared memory (distributed shared memory) that uses Internet Protocol (IP) networks. We also introduce a new method that automatically extends hardware drivers (not in the operating system kernel driver sense) into inter-process and Internet hardware services. Using DIVERSE, a program can display in a CAVE™, ImmersaDesk™, head mounted display (HMD), desktop or laptop without modification. We have developed a method of configuring user programs at run-time by loading dynamic shared objects (DSOs), in contrast to the more common practice of creating interpreted configuration languages. We find that by loading DSOs the development time, complexity and size of DIVERSE and DIVERSE user applications is significantly reduced. Configurations to support different I/O devices, device emulators, visual displays, and any component of a user application including interaction techniques, can be changed at run-time by loading different sets of DIVERSE DSOs. In addition, interpreted run-time configuration parsers have been implemented using DIVERSE DSOs; new ones can be created as needed. DIVERSE is free software, licensed under the terms of the GNU General Public License (GPL) and the GNU Lesser General Public License (LGPL) licenses. We describe the DIVERSE architecture and demonstrate how DIVERSE was used in the development of a specific application, an operator-in-the-loop Navy ship-board crane simulator, which runs unmodified on a desktop computer and/or in a CAVE with motion base motion queuing

Semi-automated creation of converged iTV services: From macromedia director simulations to services ready for broadcast

While sound and video may capture viewers’ attention, interaction can captivate them. This has not been available prior to the advent of Digital Television. In fact, what lies at the heart of the Digital Television revolution is this new type of interactive content, offered in the form of interactive Television (iTV) services. On top of that, the new world of converged networks has created a demand for a new type of converged services on a range of mobile terminals (Tablet PCs, PDAs and mobile phones). This paper aims at presenting a new approach to service creation that allows for the semi-automatic translation of simulations and rapid prototypes created in the accessible desktop multimedia authoring package Macromedia Director into services ready for broadcast. This is achieved by a series of tools that de-skill and speed-up the process of creating digital TV user interfaces (UI) and applications for mobile terminals. The benefits of rapid prototyping are essential for the production of these new types of services, and are therefore discussed in the first section of this paper. In the following sections, an overview of the operation of content, service, creation and management sub-systems is presented, which illustrates why these tools compose an important and integral part of a system responsible of creating, delivering and managing converged broadcast and telecommunications services. The next section examines a number of metadata languages candidates for describing the iTV services user interface and the schema language adopted in this project. A detailed description of the operation of the two tools is provided to offer an insight of how they can be used to de-skill and speed-up the process of creating digital TV user interfaces and applications for mobile terminals. Finally, representative broadcast oriented and telecommunication oriented converged service components are also introduced, demonstrating how these tools have been used to generate different types of services

Current and future graphics requirements for LaRC and proposed future graphics system

The findings of an investigation to assess the current and future graphics requirements of the LaRC researchers with respect to both hardware and software are presented. A graphics system designed to meet these requirements is proposed

Analysis domain model for shared virtual environments

The field of shared virtual environments, which also encompasses online games and social 3D environments, has a system landscape consisting of multiple solutions that share great functional overlap. However, there is little system interoperability between the different solutions. A shared virtual environment has an associated problem domain that is highly complex raising difficult challenges to the development process, starting with the architectural design of the underlying system. This paper has two main contributions. The first contribution is a broad domain analysis of shared virtual environments, which enables developers to have a better understanding of the whole rather than the part(s). The second contribution is a reference domain model for discussing and describing solutions - the Analysis Domain Model

Understanding Next-Generation VR: Classifying Commodity Clusters for Immersive Virtual Reality

Commodity clusters offer the ability to deliver higher performance computer graphics at lower prices than traditional graphics supercomputers. Immersive virtual reality systems demand notoriously high computational requirements to deliver adequate real-time graphics, leading to the emergence of commodity clusters for immersive virtual reality. Such clusters deliver the graphics power needed by leveraging the combined power of several computers to meet the demands of real-time interactive immersive computer graphics.However, the field of commodity cluster-based virtual reality is still in early stages of development and the field is currently adhoc in nature and lacks order. There is no accepted means for comparing approaches and implementers are left with instinctual or trial-and-error means for selecting an approach.This paper provides a classification system that facilitates understanding not only of the nature of different clustering systems but also the interrelations between them. The system is built from a new model for generalized computer graphics applications, which is based on the flow of data through a sequence of operations over the entire context of the application. Prior models and classification systems have been too focused in context and application whereas the system described here provides a unified means for comparison of works within the field

Graphics mini manual

The computer graphics capabilities available at the Center are introduced and their use is explained. More specifically, the manual identifies and describes the various graphics software and hardware components, details the interfaces between these components, and provides information concerning the use of these components at LaRC

Mixing multi-core CPUs and GPUs for scientific simulation software

Recent technological and economic developments have led to widespread availability of multi-core CPUs and specialist accelerator processors such as graphical processing units (GPUs). The accelerated computational performance possible from these devices can be very high for some applications paradigms. Software languages and systems such as NVIDIA's CUDA and Khronos consortium's open compute language (OpenCL) support a number of individual parallel application programming paradigms. To scale up the performance of some complex systems simulations, a hybrid of multi-core CPUs for coarse-grained parallelism and very many core GPUs for data parallelism is necessary. We describe our use of hybrid applica- tions using threading approaches and multi-core CPUs to control independent GPU devices. We present speed-up data and discuss multi-threading software issues for the applications level programmer and o er some suggested areas for language development and integration between coarse-grained and ne-grained multi-thread systems. We discuss results from three common simulation algorithmic areas including: partial di erential equations; graph cluster metric calculations and random number generation. We report on programming experiences and selected performance for these algorithms on: single and multiple GPUs; multi-core CPUs; a CellBE; and using OpenCL. We discuss programmer usability issues and the outlook and trends in multi-core programming for scienti c applications developers

Proceedings of the 1st Space Plasma Computer Analysis Network (SCAN) Workshop

The purpose of the workshop was to identify specific cooperative scientific study topics within the discipline of Ionosphere Magnetosphere Coupling processes and to develop methods and procedures to accomplish this cooperative research using SCAN facilities. Cooperative scientific research was initiated in the areas of polar cusp composition, O+ polar outflow, and magnetospheric boundary morphology studies and an approach using a common metafile structure was adopted to facilitate the exchange of data and plots between the various workshop participants. The advantages of in person versus remote workshops were discussed also