Re: An Event Driven Approach to Modelling Object Behaviour

Dave Raggett (
Tue, 16 Aug 94 12:56:32 BST

Peter Johnson's approach to modelling events is interesting, and
complimentary to the approach I have been thinking about.

I am interested in using scripting languages like Dylan for specifiying
how objects respond to, and send events; as well as how to generate
detailed descriptions of objects from higher level descriptions, e.g.
fractal landscapes, buildings etc. The data and scripts can be
named and cached independently.

In this scheme there are a set of basic event types like Peter
advocates, but this list can be arbitrarily extended via scripts.
The ASCII description of objects is close to what has been proposed
by Mark Pesce, but each object is bound to a procedural representation
via a name. The procedural representation defines methods for responding
to named events as well as methods for creating/deleting/displaying an
instance of that object. A meta syntax for object data is needed to
simplify the code for binding the data to the scripting language, which
isn't part of VRML as such. This will allow authors to introduce new
data types rather than being limited to a predefined set.

Is anyone interested in working with me on developing this into a
detailed proposal?

Best wishes,

Dave Raggett

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