What we're doing
The Oxford VR Group is developing a three-dimensional simulated laboratory
for the teaching of chemistry. This laboratory will be modelled using virtual
reality techniques and it will contain interactive multimedia experiments.
Essentially, the student will be able to move around the lab in a web
browser window and choose to take part in experiments that are distributed
around this virtual lab.
Each experiment will make use of the latest multimedia technology. This
We are using a variety of cutting edge software tools:
digitised video and animations of the experiment being carried out;
animated three-dimensional simulations of chemical objects (including molecules);
interactive sections where the student will be required to work out what
is going on and answer questions;
and links to other useful internet sites relating to that topic.
4.04 and Microsoft
Internet Explorer 4.0
One of the key advantages of using the world wide web to deliver educational
content is that it is independent of the platform used. The newest versions
of Netscape Navigator and Microsoft's Internet Explorer are a far cry from
the early days of hypertext authoring. They allow complex on-screen layout
using frames, tables, colours, and fonts, and - most importantly - they
allow the author to embed multimedia (such as video and animation) within
the page. Consequently, while our content is not tied to one specific platform
and can be viewed on a Mac or a PC, the most up-to-date version of the
browser becomes essential.
Virtual Reality Mark-up Language allows the author to create a 3D environment.
A VRML source file will contain a definition for each object that appears
in the environment with information about each objects location and attributes.
Examples of objects include cubes, spheres, and more complex things such
as text and lights. Solid objects can have textures applied to them. The
key disadvantages with VRML are that it is difficult to produce realistic
looking scenes (as these have to contain a lot of detail and textures),
and that navigating in the scenes is sometimes awkward. On the plus side,
simple VRML files use very little internet bandwidth and are an ideal way
to transmit technical drawings and simple environments. The rotating welcome
sign on our home page is in VRML. Try dragging your mouse over it -
you will find that you can move the sign about.
Apple QuickTime is a format for delivering video to the desktop. Digitised
video in its raw form requires very large files, and the Quick Time format
allows for compression. It is able to decode the compression on the fly
as the image plays. The newest versions of Apple's QuickTime plug-ins allow
for the use of JPEG compression and streaming (where the file begins to
play before it has finished downloading).
QuickTime VR is an extension to QuickTime which allows the viewing
of objects and panoramas in 3D. The panoramas are of most interest to us,
and a QuickTime VR file can contain many panoramas linked together to simulate
a larger environment. This is easier to witness than explain, and our Virtual
Chemistry Lab makes use of this technology if you want to try it out.
QuickTime VR is a very new technology and has a number of disadvantages.
While it is possible to move from one node to another in a virtual environment,
it is not possible to jump from a node to another web resource. Also, for
good quality images, the file sizes can be very large, and the QuickTime
VR plug-in has to wait for the entire file to download before it displays
any of the scene.
This combines the best points of QuickTime VR and VRML. It is based
on the VRML standard, but as well as allowing for the standard VRML objects
(such as spheres, cubes, and the like), it also allows panoramas and videos
to be placed in the VRML environment. Thus you get the best of both worlds:
the realism associated with QuickTime VR and the flexibility associated
with VRML. It allows a lot more interaction, including links to other web
URLs. It also makes for much smaller file sizes and only loads pieces of
the environment when they are needed, making for faster download times.
© Copyright 1996 Oxford University