Re: pw_images, UTC, TimeZones, LocalTime

[Phil P. <phi...@sw...>]

Martin Geisler wrote:
> I'm sorry that I haven't commented on those ideas before --- I would
> love to see that implemented! Do you have a SourceForge login?  If so,
> then I would be very happy to add you to the project.

I do have a login (somewhere, just need to find it again), though I 
would suggest you hold of on adding me to the project just yet.

So far I've been simply looking into the requirements and issues behind 
adding this kind of functionality. I've even done most of the work 
modifying sunrise/sunset calculations into a PHP function (probably 
needs a few 'neatness' type cleanups {eg auto-convert DMS to degrees}, 
but it works).

	function calc_SunriseSunset($date (=timestamp), $timezone (=hours from 
GMT, inc DST),
		$latitude (as decmal), $longitude (as decimal)) {}

	returns an array being sunrise-timestamp, sunset-timestamp

On any page on my website (http://home.swiftdsl.com.au/~Phil.Pierotti/), 
there's a 'widget' showing the weather (icons) for Sydney (Australia) as 
extracted by PHPWeather. If you 'mouseover' the (details) link, a DHTML 
popup (via overLib, see my credits page) in the window will show you the 
full report. The last line in said detail report uses the rise/set times 
as calculated by this function.

The other day I started looking at the PHPWeather code itself 
(spefically, to integrate calc_SunriseSunset into day/night evaluation 
for images) , and my initial (ten second) analysis was along the lines 
of "this will be non-trivial" (mainly due to my lack of familiarity with 
the code , and being relatively new to PHP programming).

Basically, I was hoping there was someone more familiar with the 
PHPWeather code who was interested in running with this now that I've 
gotten some of the basics started.

>>Or we could merely leverage the work already done by the developer
>>of AirSort:
>>
>>	http://freshmeat.net/projects/airsort/
>>
>>AirSort uses a MySQL table which includes ICAO, latitude and
>>longitude.
>>
>>GPL, even :-)

I spent yesterday playing around with AirSort and integrated it with the 
  PHPWeather driven page on my site (though it's not 'live', currently 
only on my private test server - I could post a small trimmed screenshot 
for the impatient). The biggest hassle I had was that (I think due to 
some CSS thing I'd done) IE wanted to not draw the table properly (for 
the empty cells below the point), so the pinpointing was incorrect. 
Adding in explicit heights for the table cell below the point fixed it.

I've also tweaked it for both 'large'(800x400) and 'small' (400x200) 
maps (and made small maps from the existing large ones). Still need to 
finish a few more minor 'flexibility' type changes, but it works nicely.

 From my basic testing, I suspect some of the co-ordinates are off, and 
several of the ICAOs from PHPWeather don't have entries in the AirSort 
table. Obviously some data-cleanups due here.

So at this point I'm looking to tackle the AirSort flexibility cleanups, 
and data correctness. Once that's done I'll look at more work on the 
PHPWeather Lat/Long&Rise/Set issue (since I'll have clean data to work 
with); however, as I mentioned earlier, it will probably be better (or 
at least faster) handled by someone who is already familiar with the code.

Phil P