[Gdal-dev] UTM question

[Clay, Bruce]

Is there anything in the GDAL package that can given 2 points in either
geocentric or geodetic coordinates determine the distance between the 2
points in x and y values?  I realize that UTM is in meters and within a
given zone all I have to do is subtract.  For some reason I am not
grasping what has to be done to get an accurate measurement across UTM
zones.  I like the idea of using the UTM system because it is in meters
which can easily be scaled in a scene but I can't find anything on the
web to guide me through what seem like it should be an easy step.

I am working on a 3D visualization package that will be given a stream
of WGS84 based geocentric coordinates and I need to update the position
of objects in the scene.  Since the scene is a small area with its own
sense of altitude (or elevation data) I am treating it like a flat earth
view and disregarding tilt of the patch to the global reference frame.

Thanks in advance for your help.

Bruce Clay
bclay at ball.com