Hi,

> I'm looking for a technical introduction to the squeak 
> graphic subsystems: balloon and balloon3d.  I would like to
> understand how it works. Browsing the system is really a
> hard way to learn. Maybe there is some guide?

Well, the best you can do is to read up in some general graphics text book
as the stuff in there is essentially right out of the books.

> By the way, what is the status of Balloon3d? Is it 
> maintained?

Yes.

> I found a small programming tutorial at 
> http://minnow.cc.gatech.edu/squeak/2713 which 
> includes some fixed that are not part of my 3.5 image.

Which is interesting, because I hadn't seen (or perhaps just not noticed) it
before. Thanks for pointing it out - I'm incorporating it into the SM
package right now.

> Another question: I'm looking for a way to find all methods 
> tat use a class.

To find the users of some class select the class name and hit Alt-Shift-N -
this will get you all the methods which reference that class. The same can
be done in the browser by selecting the class in question and choose "class
refs" from the class list's context menu.

> And yet another question: Is it possible to draw a simple line using 
> Balloon3d scene?

No. You'd have to draw a polygon.

Cheers,
  - Andreas