"When you start to think about data returned by a GPS
receiver, you immediately realize that it's three dimensional.
Thus, the display of GPS data will often be very well suited for
implementation in OpenGL, letting the standard do most of the heavy
lifting. It's not being lazy, it's being efficient!"
"GPS fixes include three values: longitude, latitude, and
altitude. For simple cases covering relatively small areas (a few
hundred kilometers), these can be mapped to X, Y, and Z and
displayed. However, for more advanced cases where high precision is
required, the lat, long, and altitude must be mapped onto a
spheroid as defined by the map datum."
"In order to keep our demonstration program as simple as
possible, we're going to take the easy route and do the simple
linear transform. This will be adequate for our purposes, but those
who require greater precision are encouraged to investigate the