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Geometry : |
Subject: Re: [geometry] Geometry extensions documentation, coordinate system definition and conversion.
From: Andrew Hundt (athundt_at_[hidden])
Date: 2013-03-07 16:44:32
Essentially, I would like to define the origin of a projected coordinate
system to be A WGS84 lat long coordinate I pass in. Unfortunately standard
UTM zones aren't accurate enough so I need to set the origin using the
current lat/lon location at startup then do conversions using that.
It looks like latlon.h and tmerc.h are what I want, how would I specify the
lat/lon I want for the origin? Or is this perhaps not part of the embedded
functionality?
I've been looking at the examples, and it appears the conversions are
mostly for lat-lon rather than lat-lon-altitude. Is it possible to handle
points with altitude? If not, it looks like altitude conversions can be
done with a simple offset when converting meters to meters, is that
accurate?
Also, would these conversion extensions be safe to use? I noticed the
following comment in one of the examples:
// BSG 28-10-2010
// TODO: clear up this test
// it is more a test than an example
// the results are sometimes WRONG
Thank you for all of your help with this.
Cheers!
Andrew Hundt
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