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The big central landmark<br />

VRML<br />

Some particular VRML features are used, for example levels of detail (LOD) to hide l<strong>in</strong>ks <strong>in</strong>side a globe when seen from far outside and to draw text and<br />

textures only when close enough, to reduce render<strong>in</strong>g time. Different po<strong>in</strong>ts of view (cameras) are used for the quick navigation mode.<br />

From <strong>in</strong>side a globe, we see its l<strong>in</strong>ks and also the exterior: the globes are transparent.<br />

6 Web access<br />

The 3D generator is accessible through the web and anybody can use it to generate a personal VRML scene. This is done with a CGI[*] script that calls the<br />

generator with the user's bookmarks URL as <strong>in</strong>put. If the users configuration is correctly set, a VRML browser is automatically run with the generated 3d<br />

scene.This is the URL for the generator:<br />

http://ligwww.epfl.ch/~rezzoni/VG/tform.html<br />

7 Conclusion<br />

We have shown a practical use of VRML to represent a portion of the web <strong>in</strong> 3D. This system is of course experimental and doesn't pretend to be a panacea<br />

for web navigation, <strong>in</strong> some cases us<strong>in</strong>g a pull-down menu is still faster. Even so, some issues of abstract data space visualization have been addressed and a<br />

few propositions that improve navigation and legibility have been made .<br />

Limitations<br />

With VRML version 1.0[*] only static scenes can be created. The <strong>in</strong>teraction <strong>in</strong> such scenes is limited to navigation and l<strong>in</strong>k selection, there is no way to<br />

manipulate objects and modify the scene. Because of this, it is impossible for <strong>in</strong>stance to modify the position of a bookmark <strong>in</strong>teractively. Also, the<br />

generator has to be run each time a new updated version of 3D bookmarks is wanted. There's no automatic coherence synchronization between the orig<strong>in</strong>al<br />

bookmarks file and the VRML version.<br />

This work is part of the "Web over ATM" project (EPFL, Switzerland).<br />

8 References<br />

[Bene91] Benedikt, "Cyberspace, first steps", Cambridge: MIT Press, 1991<br />

[Benf95] Benford & al., "Networked Virtual Reality and Cooperative Work" Presence (4/4), MIT Press<br />

[Carl93] Carlsson, Hagsand, "DIVE - a platform for multi-user virtual environments", Computers and Graphics, 17(6), 1993<br />

[Fair93] Fairchild & al., "Dynamic Fisheye <strong>in</strong><strong>format</strong>ion visualizations" Virtual Reality Systems, London: Academic Press, 1993

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