5.0

Chapter 5. Overview
The basis of JetStream Roamer is its ability to walk through any size model in real time. JetStream
guarantees a user-defined frame rate using a unique algorithm which automatically calculates which
items to render first during navigation, based on the size of items and distance from the viewpoint. Items
which JetStream does not have time to render are therefore sacrificed or "dropped out" in the name of
interactivity. These items are, of course, rendered when navigation ceases. The amount of drop-out
depends on several factors including: hardware (in particular graphics card and driver performance - for a
list of recommended graphics cards, visit www.navisworks.com [http://www.navisworks.com]), as well as
the size of the JetStream navigation window and the size of the model. If you wish to reduce drop-out
during navigation, you have the option to reduce frame rate and therefore trade it off against drop-out.
When working with truely large "supermodels" in JetStream, you will require a sufficient amount of RAM
to load and review the data. JetStream employs JetStream technology which optimizes the usage of the
available RAM. Before running out of memory, JetStream will page unnecesary data to the hard disk,
freeing up space for loading to continue. JetStream technology also enables the user to commence
navigating the supermodel, before it has completely loaded into memory.
JetStream is large address aware, utilizing any additional memory assignment following the 3GB switch
available on Windows XP systems.
JetStream is sold as a base product, Roamer, and a set of plugins that "plug-in" to it for additional
functionality such as for file publishing, photo-realistic rendering, clash detection and construction
sequencing. This set of user guides is organized by product, so there is a book for base Roamer, and one
for each plugin.
To start Roamer, double click on the Roamer icon on the desktop, or go to Start, Programs, JetStream,
Roamer. The following chapters will describe the interface in more detail.
JetStream contains full context sensitive Help. Click and click over the toolbar button or menu
command to display the appropriate Help topic. Or alternatively go to the Help menu.
For more hints, tips and answers to frequently asked questions, see Chapter 21, Getting Help or
alternatively, go to the JetStream website at www.navisworks.com [http://www.navisworks.com].
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