Path: utzoo!attcan!utgpu!watmath!thunder!water!wlrush
From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall)
Newsgroups: ont.events,uw.talks,uw.cs.grad
Subject: JOINT SYMBOLIC ALGEBRA AND COMPUTER GRAPHICS SEMINAR
Keywords: Dr. Eliyezer Kohen, University of Zurich ETH will speak on 
          "Rubi-AN  Open Interactive Graphics Editor."
Message-ID: <2424@water.waterloo.edu>
Date: 15 Jun 89 13:48:42 GMT
Distribution: ont
Organization: U of Waterloo, Ontario
Lines: 50

DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

JOINT SYMBOLIC ALGEBRA AND COMPUTER GRAPHICS SEMINAR

                    -Monday, June 19, 19989

Dr. Eliyezer Kohen, University of Zurich ETH will speak
on ``Rubi-AN Open Interactive Graphics Editor.''

TIME:                 3:30 p.m.

ROOM:              DC 1304

ABSTRACT

Rubi   is   an  object-oriented,  user-extensible,  and
interactive graphics editor for technical illustrations
with  overlapping  textured areas, text strings, bitmap
images  and  logos.  Rubi has been structured so that a
user  can add new object classes, new attribute values,
and  new  commands  without having access to the source
code.

As  usual  the extensibility with new object classes is
realized  by installing a class handler for that class.
Rubi   distinguishes   itself  from  other  systems  by
allowing  this type of extensibility for all the levels
of  the  editor, down to drawing a pixel on the screen.
Thus  a  new  method  can be added to an existing class
handler  without  having  access  to the source code of
that  handler.   New  attribute  values  like  new line
types,  line  patterns or texture patterns can be added
by the user to the system by dynamic loading of a small
module consisting of just a few lines.

Also  introduced  by  Rubi  is  a  novel  type  of user
interaction:   With  the  concept of interpreters every
objection  the  screen  can  be employed by the user to
invoke commands.  This gives the user a high efficiency
in  executing  complicated  graphic  commands  and  the
ability  to  form his work environment according to his
needs  without  resorting  to abstract issues like user
interface profiles.

Rubi  is  wholly  programmed  in  Modula-2 on the Ceres
personal  workstation  designed  by N. Wirth at the ETH
Zurich.   The  author was awarded the ETH Honours Medal
for his work including the Rubi project.