Re: WEB : Mapping out communal cyberspace

John W. Barrus (
Tue, 14 Jun 1994 13:31:11 -0400

On Tue, 14 Jun 1994, Mike Roberts wrote:

>I don't think that a media caching system has to necessarily be boring.
>Generic media caching could be applied to all sorts of data types; texture
>maps and object generation algorithms (assuming the existance of a scripting
>language) can be stored alongside object models. Some form of inheritance
>mechanism for the cached objects, working on similar lines to the attribute
>inheritance in currenly used in moos/other places, could aid greatly in
>producing introducing scenes from small amounts of data. For example, the
>generic teapot object could be subclassed by a user so that it's texture map
>is pink spots (both the basic teapot model and the pink spot texture map
>reside on the local cache; either on a distribution CD, or having been
>downloaded automatically at some earlier time).

I am certainly not against caching. In fact, I think that the caching in
the VR version of Mosaic will be finer-grained than a per-document cache
that is in use right now.

I also could imagine that there is a place for parametric models and
inheritance, if done correctly. However, I can imagine that most
parametric models will increase the polygon count (possibly substantially)
without adding information.

Most of the machines today will be able to draw on the order of 1000 to
10000 polygons per second (That's only 100 to 1000 per frame!!). It
doesn't take very many trees to use that up.

I agree that bandwidth can be decreased substantially. However, I don't
think that most of us will be able to display models like Barcelona in real
time (remember - only 3300 polygons). At most, Barcelona could use
inheritance for only a few chairs.

I'm not against adding caching, but I wouldn't want to spend too much time
on it up front because I think that the models we will be able to display
and work with interactively will not be all that big for the next year or

John B.


John Barrus

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