[Openexr-devel] Mac stuff

[Jo Meder]

Hi,

I downloaded everything from the CVS again a couple of nights ago, and
by following the Mac build instructions to the letter, everything built
nicely without any path adjustments. No worries there.

I've been spending a little while tonight looking at why IlmImfTest
isn't happy on OS 9. The other tests work. It looks like I'm probably
the only person here with an interest in supporting OpenEXR on OS 9 :-).
The main reason is that the HDR plugin for my app currently runs on Mac
OS 9, OS X and Windows, and when I add OpenEXR support it will be ever
so slightly more work to prevent it being available on OS 9. It's not a
big deal though.

It is interesting why it doesn't work, because I haven't yet come across
anything ( not platform dependant ) that just flat out won't work on OS
9. To my mind OS 9's big disadvantage all these years ( really, I mean
classic Mac OS rather than simply OS 9 ) has been memory related issues.
I have come across some things which have been a nightmare to debug, and
which have in the main worked fine on other platforms but have had some
subtle bugs that only spring to light when running on OS 9. Please note
I don't mean to imply that OpenEXR is buggy. It's just as likely, if not
more, that something outside my previous experience is causing problems.

Anyway, the crash seems to be happening in testHalfLut() in testLut.cpp
when the HalfLut lut is being instantiated ( line 64 ). Stepping through
the constructor, the nearest I can find is something going wrong in the
constructor of halfFunction in halfFunction.h. I'm afraid I haven't
stepped right through the loop in the  function to see exactly where
things are going wrong ( which would take a while ), I stepped a bunch
of times and then continued and crashed. I've tried this a couple of
times. A few times the debugger has caught an "uresolved page-fault
exception", but most of the time the machine just crashes hard. I must
say it's been a while since I've experienced the old OS 9
debug-crash-restart-repeat development method :-). Thinking something
might be up with VM I turned it off, but to no effect.

I could spend more time looking into this, but it'll take a little while
to figure out basically just what's going on. It's a pretty time
consuming process. I don't know how much interest there is in OpenEXR on
OS 9 in any case, I won't really be sad if I end up making the OpenEXR
output in my app just work on OS X and Windows. I must say I do
appreciate the CFM Carbon project targets though, and as I intend to
stick with CFM on OS X for the time being it would be a shame to see
them go.

I still haven't had a chance to add Windows targets to the CW projects,
but it'll be the very next thing I do with OpenEXR.

Regards,

Jo

--
Jo Meder
Planetside Software
address@hidden

Terragen for Macintosh
Photorealistic landscapes on your Mac
<http://www.planetside.co.uk/terragen/mac/>