GtkCanvas use cases

[Carlos Garnacho <carlos imendio com>]

Hi!,

I've been collecting and summarizing the use cases that popped out in
the canvas requirements thread, hopefully it's a good base to get other
use cases, but I think it already gives an idea of the heterogeneous
expectations for the canvas, here's the summary:

* Interactive diagrams 
      * plots 
      * UML editor, entity-relationship, ... 
      * Desktop publishing app 
      * Multi-track audio editor 
      * Air traffic controller simulator. 
      * Database relationship viewer. 
      * PIM Synchronizer connection viewer. 
      * ... 
* substitute existing widgets with a new canvas based widget system (can
be done incrementally)
* Possibly several views on the same data 
* Printing 
* Creating fancier UIs for apps, possibly with embedded widgets
  (control-center shell, ?MugShot, something like GMail, ...) 
* Animations and games 
* show and manipulate pre-drawn graphical content (i.e. load from
  a .svg, get objects by their name, ...) 
* Having a concept of "scale" for zoomable UIs.

On related news, I've created in l.g.o a page to keep track of use
cases, as well as a feature matrix for available canvases plus other
reference ones, the page is at:

http://live.gnome.org/ProjectRidley/CanvasOverview

It'd be great if maintainers filled up any missing info. And of course
any other additions/comments are welcome :)

Regards,
   Carlos