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Runaway Universe
Preparing Yourself and Your Computer for VRML
back to Tour the Universe

We have created a 3-D model of nearly two thousand galaxies that you can download over the Web and view on your computer. To use this 3-D model, however, requires that you have a "fast enough" computer, install some software, and learn how to move around in 3-D. It takes some work, but nobody said exploring the universe would be easy. We'll try to walk you through the process in four steps.

    Step 1 - VRML & 3-D on the Web
    Step 2 - System Requirements and Warning
    Step 3 - Download a VRML Browser Plug-in
    Step 4 - Top 10 Things to Know About VRML
    "Local Universe in 3-D" VRML World
    Credits


Step 1 - VRML & 3-D on the Web
VRML is an acronym for Virtual Reality Modelling Language; it is usually pronounced "ver-mul." It is a programming language used to describe 3-D models, called "worlds." A VRML world file, which usually has the extension ".wrl", is text file of instructions (or a compressed text file), and thus easily distributable over the Web. An international VRML standard has been established so that any standard-conforming worlds can be viewed by any standard-conforming VRML browser. VRML browsers are generally distributed as plug-ins to Internet browsers, and most are free.

Beyond just VRML, you may encounter the term Web3D. Web3D encompasses all sorts of technologies for distributing 3-D content over the internet, including Java3D, MPEG4, and about 100 proprietary technologies from 100 different companies. To date (Nov 2000), VRML is the only Web3D technology that is standardized, in widespread use, on several platforms, and freely available. But who knows what the future will bring?


Step 2 - System Requirements
The universe is a big place. It is hard to squeeze it down to fit inside a computer. It is even harder when you want to interact with that universe in 3-D.

In short, older computers are unlikely to be able to run this 3-D model. Based on our (admittedly limited) testing, we recommend:
  • PC (minimum) - Pentium II 233 MHz, 64 MB memory
  • PC (recommended) - Pentium III 500 MHz, 128 MB memory, 3Dfx Voodoo 3 or NVidia TNT2 graphics

  • Mac (minimum) - not tested sufficiently
  • Mac (recommended) - G3, PowerPC 300MHz, 128 MB memory

  • SGI (minimum) - O2 MIPS R5000 200 MHz, 128 MB memory
  • SGI (recommeded) - not tested sufficiently
The performance ratings of our test systems are listed below:

Load Time* Response Computer System
75 seconds slow, stuttering movement SGI O2, MIPS R5000 200 MHz, 128 MB memory, CRM graphics
45 seconds OK, jittery movement PC (laptop), Pentium II 233 MHz, 64 MB memory, Neomagic 128XD graphics
30 seconds good, some hiccups PC, AMD K6-2 450 MHz, 128 MB memory, 3Dfx Voodoo 3 2000 graphics
15 seconds excellent, smooth movement PC, Pentium 3 550 MHz, 384 MB memory, NVidia Riva TNT2 graphics
15 seconds excellent, smooth movement Mac G3, PowerPC 350 MHz, 128 MB memory

*NOTE: Load times do not include the time required to download the VRML world file across the internet, which is highly dependent on your connection speed and on internet traffic.

Warning
Due to the very wide diversity in graphic cards and installed software on computers, we know there will be conflicts and bugs out there—potentially some serious ones that may affect how your computer operates. We can't fix such bugs. We probably can't even give you good advice on such bugs. We just created a VRML world. We have no control over the VRML browser or your internet browser or your graphics card drivers. About the only advice we can provide is to be sure that you are using the latest version of the plugin.

To learn more, go to known bugs within "Top Ten Things to Know About VRML."


Step 3 - Download a VRML Browser Plug-in
VRML worlds are viewed using a VRML browser plug-in to your internet browser. There are many VRML browser plug-ins available, but we recommend CosmoPlayer 2.1. It is available for PCs, Macs, and SGIs as a plug-in to Netscape Navigator and Microsoft Internet Explorer.

To download CosmoPlayer for PCs and Macs, go to:
    http://ovrt.nist.gov/cosmo/

To download CosmoPlayer for SGIs, go to:
    http://www.sgi.com/software/cosmo/irix_player.html

Please look at these Installation Notes for tips on installing CosmoPlayer. Also note that CosmoPlayer was developed a couple years ago and has not been updated. It has some bugs that we will discuss in Step 4. Further, the Mac version was never fully released; it was only released in "beta" version. Even with these caveats, we feel it is the best VRML browser plug-in.


Step 4 - Top 10 Things to Know About VRML
Exploring space in 3-D is unfamiliar to most everybody. Even those who have played hundreds of hours of Quake have been moving mostly in familiar 2-D terrain: where there are floors that define 2-D levels and stairs take you between levels. Intergalactic space has no floors, walls, or ceilings.

Everyone must learn to move around in 3-D, and here that means learning to use a VRML browser plug-in. The link below is a quick start guide: the ten things everyone must know to have success. It will get you up and running with the least amount of pain. Learn these points, practice them, and you are on your way to becoming a master of 3-D. The instructions on these pages are customized to the CosmoPlayer 2.1 VRML browser plug-in, but the concepts are applicable to all browsers.

    Top 10 Things to Know About VRML


"Local Universe in 3-D" VRML World
Once you've installed a VRML browser plug-in and have learned how to use it, you are ready to explore the local universe.

The "Local Universe in 3-D" VRML world contains 1793 nearby galaxies and covers a good fraction of the Virgo Supercluster, including the Virgo Cluster and the Local Group of Galaxies. Our Milky Way Galaxy is located at the origin of the coordinate axes, since it is our reference point.


Take the Tour "Local Universe in 3-D" VRML World (151KB)
Click on the image at left to download the "Local Universe in 3-D" VRML world. After the file has been downloaded to your computer, you can expect it to take anywhere from 15 seconds to a couple minutes to load the world and the first graphics to appear on the screen.


Problems?
The above link is to a compressed version of the VRML world. Almost all VRML browsers can handle compressed files. If your browser complains that the above file is not a VRML world, you may want to try downloading the uncompressed version. But beware, the uncompressed version is 1.2 megabytes, almost 10 times larger.

    Uncompressed Galaxies in 3-D VRML World (1.2 MB)


Viewing Hints
  • Look at a screen shot - You can use the screeen shot image to adjust your monitor, so that you can see all the details in the model. If you know how to adjust the color curve (i.e., gamma), it can greatly help you see more range of detail.

  • Turn off the lights - If you turn off the lights in the room, you will be able to see more in the VRML World. This is especially true because space is black, and you need to see color contrasts against black.

  • Patience - On the mininum level computers, it will take some time between when you click and when the computer responds. Don't try to move around quickly. Move slowly, and learn by practice how fast your computer will let you explore. Note that the more galaxies that are in view, the slower the computer will go.

  • Viewpoints - Remember that viewpoints will take you automatically to interesting places in the VRML world. If you get lost, disoriented, or want to get someplace easily, use the list of viewpoints.

Credits
Dr. Frank Summers, Hayden Planetarium, New York City - VRML model & related programming, web pages

Dr. R. Brent Tully, University of Hawaii - Galaxy data set, scientific advisor, user testing

Jacob Barandess - Additional VRML programming

National Science Foundation - Support through NSF Informal Science Education grant ESI-9814279




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