>>| | EMBEDDED PROGRAM OBJECTS IN DISTRIBUTED HYPERMEDIA SYSTEMS
>>| |
>>| | Researchers at the U. of California have created software for embedding
>>| | interactive program objects within hypermedia documents. Previously,
>>| | object linking and embedding (OLE) has been employed on single machines or
>>| | local area networks using MS Windows -TM-. This UC software is the
>>| | first instance where program objects have been embedded in documents
>>| | over an open and distributed hypermedia environment such as the
>>| | World Wide Web on the Internet.
>
>This is very interesting... But, I don't think this is the first case
>of program objects embedded in docs and transported over the WWW.
>ViolaWWW has had this capabilities for months and months now.
>
As Pei's paper on Viola states, that package did not support what it calls
"embeddable program objects" until 1994. As our WWW server shows
(http://visembryo.ucsf.edu/), we demonstrated a fully functional volume
visualization application embedded within a WWW document in 1993.
Furthermore, Viola merely implements an internal scripting language that
allows one to code "mini application" scripts that are transferred to the
local client, and then interpreted and run locally on the client machine. As
Pei correctly notes in his paper, this is similar to the use of EMACS'
internal programming capabilities.
What we have accomplished is much different. Just as the Microsoft Windows
OLE function allows any OLE-compliant application to be embedded, in its
native form, within, for example, a MS Word for Windows document, we can
embed ANY interactive application IN ITS NATIVE FORM within a WWW document.
These program objects not only effectively encapsulate both data and
methods, they also "encapsulate" computational resources, since the the
program objects are, themselves, client server applications that actually
run remotely on one or more distributed computational servers. The access
of the remote machines is transparent to the user, allowing, for example,
someone running a WWW client on a laptop to interactively manipulate and
analyze huge datasets running on a distributed array of supercomputers
distributed across the country.
The applicability for VR systems is obvious. One of the major hurdles to
widespread acceptance of VR technology has been the burden of large local
computational resources. Our approach allows that computational burden to
be distributed to suitable remote "visualization engines," thereby allowing
users to employ low-end machines to access sophisticated graphical
environments. It further allows easy access to those applications through
the World Wide Web.
**************************************************************************
* Michael D. Doyle, Ph.D. email: miked@visembryo.ucsf.edu *
* Director, Health Informatics Lab phone: (510)522-5275 *
* Department of Anatomy, School of Medicine fax: (510)522-4439 *
* University of California, San Francisco pager: (415)719-4557 *
* 5 Remmel Court http://visembryo.ucsf.edu/ *
* Alameda, CA 94502 alternate email: mddoyle@netcom.com *
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