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TerraVisionTM can browse data that is distributed over a wide-area
network, e.g. the Web, as well as locally installed data. TerraVisionTM
was specifically designed to cope with the inherent unpredictabilities
of accessing data over a network.
TerraVisionTM can view massive datasets, in the order of terabytes.
It achieves this by employing powerful optimization algorithms including:
view frustum culling, terrain and imagery level-of-detail, horizon
culling, caching, and prediction.
TerraVisionTM can handle datasets in a variety of geographic coordinate
systems, e.g. lat/long, UTM, LVCS, and can transform these on the
fly to a round-earth, or geocentric, representation.
TerraVisionTM can view multiple datasets at once. For example,
you can have a 1 km resolution globe model, with a 25 m model of the
San Francisco Bay Area, and 1 m inset for Palo Alto.
TerraVisionTM lets you open up multiple viewer windows. This lets
you look at the same dataset from different perspectives at the same
time, or different combinations of sets. You can even slave the view
of one viewer to another.
3-D models can overlayed on the terrain to provide support for cultural
features, such as buildings and roads, and atmospheric simulations,
such as wind vectors and clear air turbulence models. We use the Virtual
Reality Modeling Language (VRML97) extension GeoVRML to
represent all models.
||OGC WMS Support
SRI has created a Web Map Server interface for the
TerraVision datasets. This is a standard for serving
maps over the web produced by the OpenGIS
Consortium. TerraVision can query a WMS and browse
imagery or elevation datasets from that server.
You can setup predefined flights paths by marking a number of viewpoints
and then telling TerraVisionTM to fly a path connecting those
viewpoints. You can vary the velocity, loop the path, close the loop,
and select linear or spline interpolation.
If you like a particular viewpoint, for example if you have found
your house, then you can bookmark that viewpoint and TerraVisionTM
will remember it so that you can fly back to it later, or next time
you use TerraVision.
A simple HUD is available to provide information such as viewer location
(in lat/long), orientation, number of tiles display, data burst rate,
and frame rate.
The 2-D Viewer is provided to give pan and zoom capabilities with
a constrained downward looking viewpoint. The user can switch between
3-D and 2-D mode at will.
The Map Viewer allows a user to see all dataset extents (green), view
areas (blue), and flight paths (orange) overlaid on a map. Users can
click over the map to teleport the 3-D Viewer to that location.
TerraVisionTM uses the NetLogger API from LBNL to provide logging
features and graphically view the state of the application. This includes
features such as monitoring the requesting and reading of data over
the network, texture cache usage, timings for scene rendering, visibility
A web-based user guide is available to help new users familiarise
themselves with the TerraVisionTM system. TerraVisionTM offers Help
menus which bring up appropriate sections of this user guide in their
Copyright © 2002 SRI International. All rights reserved.
For more information, please contact: firstname.lastname@example.org.
Last updated: Thursday, 28-Jun-2001 16:47:07 PDT.