[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

A couple of observations on IDL 5.4 final



I got 5.4 final today. I'm a little surprised, as I didn't think it would
get to the other side of the world (more or less) so fast.

A couple of minor observations.

1) Regular newsgroup readers may recall several long postings (involving
mainly me & JD Smith, as I recall) on keyword inheritance by reference
through multiple layers of the calling stack. IDL 5.4's behaviour is
unchanged, which I find a bit disappointing as *nobody* suggested it was
correct. What is this behaviour? Let's not go there! All I'm willing to say
is that it's a little quirky.

2) For several IDL versions I have had some very clever (I thought) routines
for putting labels between the tick marks of object graphics axes. They
relied on intercepting and modifying the (undocumented) Draw method of an
IDLgrAxis. Well, let this be a lesson to you all! When RSI say, "Please
don't use undocumented routines because they may be withdrawn in future
versions" they mean it! Yes, you guessed it, IDLgrAxis::Draw is no longer
called when an axis is drawn. Serves me right. Maybe I can achieve the
result using IDLgrModel::Draw, which *is* documented.

---
Mark Hadfield
m.hadfield@niwa.cri.nz  http://katipo.niwa.cri.nz/~hadfield/
National Institute for Water and Atmospheric Research
PO Box 14-901, Wellington, New Zealand