Re: Question about handles

[Don Blaheta <blahedo blahedo org>]

Ok.  I've done up a diagram of what's going on in memory for a simple
diagram involving a Box and three Lines, and posted it to my webpage
(link below).  The "grammar" of the diagram is this: every rectangle
represents a chunk of memory.  Above the rectangle in italic Times is
the type of the chunk, and to its left in upright Courier is its name
(if any).  DO and CP are abbreviations of DiaObject and ConnectionPoint,
respectively.  If a rectangle is inside another rectangle, that means
the memory is actually contained (i.e. it's included as a struct), not
just logically related.  Arrows represent pointers.  NULL pointers are
represented with an X through the rectangle.  The size of the typename
is not significant except that I've enlarged the ones I think you'll
most want to see.  I've omitted a number of the member variables (with
line attributes, locations, etc) for legibility.

Anything in black is part of the core shape, and would be there even if
nothing were connected.  The pointers and objects that collectively
represent the connections are colour-coded; the three active connections
are circled in red, green, and blue in the reference image, and pointers
involved in representing each connection are coloured to match.  The
connection stuff is in a separate layer in the Dia file, which you can
make invisible if you want to see the underlying memory layout better.

I've also exported it to PDF in case you don't have your Dia
installation handy. :)

Please let me know if I've got anything wrong!  I think I finally, er,
got a handle on it, but it's complex enough I'm perfectly willing to
believe it's not quite right yet.

The diagrams are linked from this page:

  http://www.blahedo.org/dia/

-- 
-=-Don Blaheta-=-=-blahedo blahedo org-=-=-=-<http://www.blahedo.org/>-=-
Tell a man that there are 400 billion stars and he'll believe you.
Tell him a bench has wet paint and he has to touch it.