Re: [guppi-list] New Guppi Snapshot

[Neil J Pilgrim <eennjp electeng leeds ac uk>]

Jon Trowbridge wrote:
> On Tue, Aug 29, 2000 at 03:30:47PM +0100, Neil J Pilgrim wrote:

> > [tangent]
> > I have to confess to wondering why C++ was neglected before: GTK+ uses
> > quasi-OO techniques so what difference would it make to people needing
> > to learn the code structuring, etc.?
> > [/tangent]
> 
> If I read your question properly, the answer is "basically none".
> Guppi has a (IMHO) nice, clean OO design --- before embarking on Guppi
> I'd basically spent 5 or 6 years doing all C++ all the time.
> 
> The GTK+ object system gives you pretty much everything you need to do
> good OO programs in C.  There are really only three main things missing:
> 
> (1) Syntactic Sugar.  All those macro calls can be annoying.
> (2) Multiple inheritance.  This hasn't presented a problem in Guppi so
>     far.
> (3) Templates.  I really like templates, and miss not having them
>     around.  But, on the other hand, they also tend to cause a lot of
>     problems...
> 
> Actually, the GTK+ system better resembles Smalltalk-ish OO than
> C++ish OO, since there is a lack of all that strict compile-time checking.

I suppose the absence of an up-to-date and working GTK-- version didn't
help with developing guppi in C++ too.

One thing I was wondering was whether it is possible to use some too
like doc++ to generate documentation from the code; the use of OO in C
doesn't strike me as easy to parse in this way however.

> > Well no, it enables extension of the range in plots, for example. My
> > point was really that you should be able to do the drag in reverse - ie.
> > start 'outside' and work inwards. Not that important, just slightly
> > asymmetric ;)
> 
> It is asymmetric.  But there is one problem: how are you supposed to
> know which mouse-clicks outside of the plot range are the start of a
> drag?  What if you have two separate scatter plots in the window ---
> which one gets it?

A good point (only one?) :)
Solved by having graph-by-graph focus? Also, you could at least allow
drags to start over axis-labels and so on?

> > So far I've not managed to trigger those again, I just noticed them when
> > I went back to the xterm I loaded from...I'll let you know if I find
> > them again. I think it happened when I hit the home on the graph centre,
> > but I'm not sure specifically what I did before that.
> 
> If you (or anyone reading this) can figure out how to reproduce that
> behavior, please let me know.  All Gtk-WARNINGs must be destroyed.

Still trying...

Further points (!):
- It is useful to plot an 'index' on an axis in some cases. So if you
have a file containing simply a list of numbers, then those values
appear on one axis, and by default (before applying another data set)
the other axis could display the 'index' of each data point?
- applying colours per index would be nice too.
=> maybe have 'index' as a field in a data set (perhaps a configuration
option though, to avoid needless space if people don't want it)

Also just got:

Gtk-WARNING **: gtk_signal_disconnect_by_data(): could not find handler
containing data (0x816D170)

Trying to find this one too :(

-- 
Neil