U.S. EPA Scientific Visualization Center
86 Alexander Drive
Research Triangle Park, North Carolina 27711
Phone: (919) 541 - 0207
FAX: (919) 541 - 0056
Within the next five years, the interactive visualization of scientific data on Microsoft DOS /Windows-based personal computers will be a reality. Advances in hardware that supports the creation and interactivity of three-dimensional computer graphics at the personal computer level have occurred or are under rapid development. Applications programming interfaces already exist. Versions of visualization toolkits and other high-end computer graphics software for Windows NT have reached the commercial market.
The development of Internet browsing tools that permit the visual display and exploration of three dimensional data and graphics is also underway. This will allow low-end personal computers, with minimal graphics hardware, to support the exploration of scientific and information visualization.
This discussion highlights these activities.
3-D Graphics Hardware Advances for Personal Computers:
There are four major features associated with hardware that support three-dimensional graphics. These are: (a) Z buffering; (b) color interpolation; (c) texture mapping; and (d) rendering of three- dimensional triangles and polygons. For personal computer architectures, the market trend is to package these components into an accelerated VGA chip with video-processing features. This hardware is defined as a video graphics controller. Presently, there are no benchmarks or standard agreements on how to measure performance of PC-based video graphics controller chips.
Currently, 3DLabs' GLINT chip is the dominant high-end accelerated VGA chip. A listing of companies that are currently shipping or are about to release graphics boards based on the GLINT chip can be found at (http://www.3DLabs.com/boards.htm) . Intel and Lockheed Martin have announced a collaboration that will incorporate Lockheed Martin's REAL3D graphics technology into future Intel hardware designs. Results from the Intel and Lockheed Martin collaboration are expected to be available during 1997, (http://www.lmco.com/real3d/press.html).
3D Application Programming Interfaces (APIs) for Personal Computers:
Application programming interfaces (APIs) support the development of software and applications. Three-dimensional graphics (3D) APIs attempt to address: (1) PCs with no graphics hardware; (2) PC graphics hardware with different levels of acceleration; and (3) a broad range of applications and software developer requirements. The three most widely available three- dimensional graphics APIs for personal computers are Direct 3D from Microsoft; QuickDraw 3D RAVE (Rendering Acceleration Virtual Engine) from Apple Computers; and OpenGL from Silicon Graphics. Direct3D is primarily intended for computer games applications and was unveiled in April 1996. QuickDraw 3D RAVE is also intended for the games market on both Power Macintosh and PC platforms. OpenGL is oriented towards high-end computer graphics applications, like scientific and information visualization, (http://www.sgi.com/Technology/openGL/). Currently, Microsoft provides OpenGL development tools for Windows 95 and Windows NT.
Scientific Visualization and Graphics Rendering Software for Personal Computers:
As a result of 3D graphics hardware and API advances for personal computers, scientific visualization and computer graphics software currently available on Unix workstations is beginning to be available for Windows 95 and Windows NT platforms. The Application Visualization System (AVS) is already commercially available for Windows NT, (http://www.avs.com/) . IBM Visualization Data Explorer has also successfully ported its visualization toolkit environment to Windows NT, (http://www.almaden.ibm.com/dx/) . Microsoft's high-end computer animation and modeling software, SoftImage, is available for the Windows NT platform, (http://www.microsoft.com/Softimage/Products/3DWNT/) . A listing of public domain visualization software currently available on personal computers and Unix workstations can be found at (http://www.cs.ubc.ca/spider/ladic/software.html) .
The "Network Computer" or "Simply Interactive PC" Concept:
In addition to developments in computer graphics hardware and software for personal computers, a number of companies are developing a scaled down internet-access personal computer. The internet-access personal computer is intended to be completely network dependent, with limited to no storage capablities. Navigation aids, likeWorld Wide Web (WWW) browsing tools, will be the fundamental software for using this applicance. In May 1996, Apple, IBM, Oracle, Sun Microsystems and Netscape formally announced a set of guidelines for developing network computing devices. This information can be found at (http://www.nc.ihost.com) . Oracle and IBM, and Apple have announced intents to release internet-access personal computers in late 1996. Oracle has stated that it hopes to sell the appliance computer for around $500.
Microsoft has also announced a strategy to create the "Simply Interactive PC," which is defined as "the best platform for entertainment, Internet access and communications", (http://www. microsoft.com/windows/events/winhec.htm) . This is part of Microsoft's PC 97 initiative and was featured at the April 1 - 3, 1996 WinHEC 96 conference in San Jose, California.
3-D Browsing Tools for the Simply Interactive PC:
WWW browsing tools, like Netscape and Mosaic, will be the information visualization software for supporting exploration on Internet-access personal computers or other personal computers with limited graphics hardware acceleration. Effective display and interaction with three-dimensional objects on the Internet will be achieved through browsing tools that support the Virtual Reality Modeling Language (VRML). Information on VRML efforts and software browsers can be found at the VRML repository located at the San Diego Supercomputer Center (http://www.sdsc.edu/vrml/) . In early January, 1996, the VRML Architecture Group (VAG) issued a request for the next major revision to VRML (VRML 2.0), (http://vag.vrml.org/) . Microsoft, Silicon Graphics, Apple, Sun, and others submitted proposals. The "Moving Worlds" proposal from Silicon Graphics was accepted as the basis for the VRML 2.0 standard. The VRML 2.0 standard was completed in August 1996 and released at the ACM SIGGRAPH's annual conference, (http://vrml.sgi.com) .
Summary & Concluding Remarks:
The personal computer is rapidly evolving towards supporting interactive scientific and information vis