Path: utzoo!attcan!uunet!mcsun!ukc!harrier.ukc.ac.uk!rlh2
From: rlh2@ukc.ac.uk (Richard Hesketh)
Newsgroups: comp.windows.x
Subject: An R5 wish for the X Toolkit
Message-ID: <5276@harrier.ukc.ac.uk>
Date: 14 Aug 90 12:36:16 GMT
Reply-To: rlh2@ukc.ac.uk (Richard Hesketh)
Organization: Computing Lab, University of Kent at Canterbury, UK.
Lines: 37

Two (probably) major additions to the Xt Intrinsics would be nice:

1)  Provide detailed support for "graphics objects", by this I mean
    rectangles, circles, points and polygons.  These should be scalable
    and can be overlaid on top of each other, have their own graphics
    contexts and have the ability to dump their description somewhere
    (a sort of meta-file I suppose).  If anybody has seen the
    InterViews demo (!) program "Idraw" they will known the type of
    objects I mean.

2)  Provide a mechanism to allow tracking of resource values.  For example
    this would allow an application to register interest in a particular
    resource in a particular widget instance and be informed via a callback
    when this resource changes.  I suspect this would be easier to implement
    than a more general mechanism that would allow applications to register
    interest using a wildcard scheme (i.e. "*Background" = tell me about
    any changes in any resource whose class is "Background" in any widget
    instance) but of course not being as powerful.

    I would see this being implemented as part of the SetValues functions.
    It would of course have to have no impact on existing widget code.

1) may fill the gap left by the toolkit when it comes to doing any graphics
operations in a toolkit based app .. i.e. having to delve in deep in to Xlib.

2) would help direct manipulation applications including user interface
builders (my interest) no end.

1) and 2) together could make a neat ``graphical constraints'' system
making it easier to create graphical languages and other direct manipulation
applications using Xt.

Richard Hesketh   :   @nsfnet-relay.ac.uk:rlh2@ukc.ac.uk
		  :   rlh2@ukc.ac.uk    ..!mcvax!ukc!rlh2
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Computing Lab., University of Kent at Canterbury,
Canterbury, Kent, CT2 7NF, United Kingdom.    Tel: +44 227 764000 ext 7620/3682