[mcclim-devel] question about display functions and control apps

[Paolo Amoroso]

rpgoldman at real-time.com writes:

> The examples I have seen of display functions and McCLIM, it seems
> like there are two dominant models: one where the user does some
> commands, and the application pane's display function stays in synch
> by updating at every command loop (I suppose this is the MVC model);

Section 7 "CLIM: Presentation Based Interfaces" (page 31) of this
paper:

  New Architectural Models for Visibly Controllable Computing: The
  Relevance of Dynamic Object Oriented Architectures and Plan Based
  Computing Models
  ftp://publications.ai.mit.edu/ai-publications/2004/AIM-2004-005.pdf

briefly describes the relations between CLIM and MVC.


> Question:  what about the case where you want to watch something "out
> there" that is not under the control of the command loop.  I'm
> thinking in particular about controls applications, where you might
> want to update a display that shows the current state of the plant.

If I understand correctly, in this case you may call
REDISPLAY-FRAME-PANE, typically from an application command or some
state updating function.  A program that uses this approach is:

  KYTRON on the Moon
  http://artm-friends.at/rm/kytron/kytron-clim.html

Check the CLIM 2 version:

  http://artm-friends.at/rm/kytron/kytron2.lisp.txt

See for example the commands for adding a new element--crater,
mountain, ecc.--to the environment.


Paolo
-- 
Why Lisp? http://alu.cliki.net/RtL%20Highlight%20Film